bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting the Recurrence of Gastric Cancer Using the Textural Features of Perigastric Adipose Tissue on [18F]FDG PET/CT
Authors: Ahn Hyein , Song Geum , Jang Si-Hyong , Son Myoung , Lee Hyun , Lee Moon-Soo , Lee Ji-Hye , Oh Mee-Hye , Jeong Geum , Yun Jong , Lee Sang , Lee Jeong
Published: October 2022

This study aimed to assess the relationship between the histopathological and textural features of perigastric adipose tissue (AT) on 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) and to evaluate the prognostic significance of perigastric AT textural features in predicting recurrence-free survival (RFS) in patients with gastric cancer. Sixty-nine patients with gastric cancer who underwent staging [18F]FDG PET/CT and subsequent curative surgery were retrospectively reviewed. Textural features of perigastric AT were extracted from PET images. On histopathological analysis, CD4, CD8, and CD163 cell infiltration and matrix metalloproteinase-11 and interleukin-6 (IL-6) expression in perigastric AT were graded. The degree of CD163 cell infiltration in perigastric AT was significantly correlated with the mean standardized uptake value (SUV), SUV histogram entropy, grey-level co-occurrence matrix (GLCM) energy, and GLCM entropy of perigastric AT. The degree of IL-6 expression in the perigastric AT was significantly correlated with the mean and median SUVs of perigastric AT. In multivariate survival analysis, GLCM entropy, GLCM dissimilarity, and GLCM homogeneity of perigastric AT were significant predictors of RFS. The textural features of perigastric AT on [18F]FDG PET/CT significantly correlated with inflammatory response in perigastric AT and were significant prognostic factors for predicting RFS in patients with gastric cancer.
A Dpagt1 Missense Variant Causes Degenerative Retinopathy without Myasthenic Syndrome in Mice
Authors: Hyde Lillian F. , Kong Yang , Zhao Lihong , Rao Sriganesh Ramachandra , Wang Jieping , Stone Lisa , Njaa Andrew , Collin Gayle B. , Krebs Mark P. , Chang Bo , Fliesler Steven J. , Nishina Patsy M. , Naggert Jürgen K.
Published: October 2022

Congenital disorders of glycosylation (CDG) are a heterogenous group of primarily autosomal recessive mendelian diseases caused by disruptions in the synthesis of lipid-linked oligosaccharides and their transfer to proteins. CDGs usually affect multiple organ systems and vary in presentation, even within families. There is currently no cure, and treatment is aimed at ameliorating symptoms and improving quality of life. Here, we describe a chemically induced mouse mutant, tvrm76, with early-onset photoreceptor degeneration. The recessive mutation was mapped to Chromosome 9 and associated with a missense mutation in the Dpagt1 gene encoding UDP-N-acetyl-D-glucosamine:dolichyl-phosphate N-acetyl-D-glucosaminephosphotransferase (EC 2.7.8.15). The mutation is predicted to cause a substitution of aspartic acid with glycine at residue 166 of DPAGT1. This represents the first viable animal model of a Dpagt1 mutation and a novel phenotype for a CDG. The increased expression of Ddit3, and elevated levels of HSPA5 (BiP) suggest the presence of early-onset endoplasmic reticulum (ER) stress. These changes were associated with the induction of photoreceptor apoptosis in tvrm76 retinas. Mutations in human DPAGT1 cause myasthenic syndrome-13 and severe forms of a congenital disorder of glycosylation Type Ij. In contrast, Dpagt1tvrm76 homozygous mice present with congenital photoreceptor degeneration without overt muscle or muscular junction involvement. Our results suggest the possibility of DPAGT1 mutations in human patients that present primarily with retinitis pigmentosa, with little or no muscle disease. Variants in DPAGT1 should be considered when evaluating cases of non-syndromic retinal degeneration.
A Short Promoter Region Containing Conserved Regulatory Motifs Is Required for Steroidogenic Acute Regulatory Protein (Star) Gene Expression in the Mouse Testis
Authors: Bouchard Marie France , Picard Julia , Tremblay Jacques J. , Viger Robert S.
Published: October 2022

In the testis, Leydig cells produce steroid hormones that are needed to masculinize typical genetic males during fetal development and to initiate and maintain spermatogenesis at puberty and adulthood, respectively. Steroidogenesis is initiated by the transfer of cholesterol from the outer to the inner mitochondrial membrane through the action of steroidogenic acute regulatory protein (STAR). Given its importance for the steroidogenic process, the regulation of STAR gene expression has been the subject of numerous studies. These studies have involved the characterization of key promoter sequences through the identification of relevant transcription factors and the nucleotide motifs (regulatory elements) that they bind. This work has traditionally relied on in vitro studies carried out in cell cultures along with reconstructed promoter sequences. While this approach has been useful for developing models of how a gene might be transcriptionally regulated, one must ultimately validate that these modes of regulation occur in an endogenous context. We have used CRISPR/Cas9 genome editing to modify a short region of the mouse Star promoter (containing a subset of regulatory elements, including conserved CRE, C/EBP, AP1, and GATA motifs) that has been proposed to be critical for Star transcription. Analysis of the resultant mutant mice showed that this short promoter region is indeed required for maximal STAR mRNA and protein levels in the testis. Analysis also showed that both basal and hormone-activated testosterone production in mature mice was unaffected despite significant changes in Star expression. Our results therefore provide the first in vivo validation of regulatory sequences required for Star gene expression.
The Involvement of Smooth Muscle, Striated Muscle, and the Myocardium in Scleroderma: A Review
Authors: Bratoiu Ioana , Burlui Alexandra Maria , Cardoneanu Anca , Macovei Luana Andreea , Richter Patricia , Rusu-Zota Gabriela , Rezus Ciprian , Badescu Minerva Codruta , Szalontay Andreea , Rezus Elena
Published: October 2022

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by heterogeneous changes involving numerous organs and systems. The currently available data indicate that muscle injury (both smooth and striated muscles) is widespread and leads to significant morbidity, either directly or indirectly. From the consequences of smooth muscle involvement in the tunica media of blood vessels or at the level of the digestive tract, to skeletal myopathy (which may be interpreted strictly in the context of SSc, or as an overlap with idiopathic inflammatory myopathies), muscular injury in scleroderma translates to a number of notable clinical manifestations. Heart involvement in SSc is heterogenous depending on the definition used in the various studies. The majority of SSc patients experience a silent form of cardiac disease. The present review summarizes certain important features of myocardial, as well as smooth and skeletal muscle involvement in SSc. Further research is needed to fully describe and understand the pathogenic pathways and the implications of muscle involvement in scleroderma.
Molecular Characterizations of the er1 Alleles Conferring Resistance to Erysiphe pisi in Three Chinese Pea (Pisum sativum L.) Landraces
Authors: Sun Suli , Deng Dong , Wu Wenqi , He Yuhua , Luo Gaoling , Du Chengzhang , Duan Canxing , Zhu Zhendong
Published: October 2022

Powdery mildew caused by Erysiphe pisi DC. is a major disease affecting pea worldwide. This study aimed to confirm the resistance genes contained in three powdery mildew-resistant Chinese pea landraces (Suoshadabaiwan, Dabaiwandou, and Guiwan 1) and to develop the functional markers of the novel resistance genes. The resistance genes were identified by genetic mapping and PsMLO1 gene sequence identification. To confirm the inheritance of powdery mildew resistance in the three Landraces, the susceptible cultivars Bawan 6, Longwan 1, and Chengwan 8 were crossed with Suoshadabaiwan, Dabaiwandou, and Guiwan 1 to produce F1, F2, and F2:3 populations, respectively. All F1 plants were susceptible to E. pisi, and phenotypic segregation patterns in all the F2 and F2:3 populations fit the 3:1 (susceptible: resistant) and 1:2:1 (susceptible homozygotes: heterozygotes: resistant homozygotes) ratios, respectively, indicating powdery mildew resistance in the three Landraces were controlled by a single recessive gene, respectively. The analysis of er1-linked markers and genetic mapping in the F2 populations suggested that the recessive resistance genes in three landraces could be er1 alleles. The cDNA sequences of 10 homologous PsMLO1 cDNA clones from the contrasting parents were obtained. A known er1 allele, er1-4, was identified in Suoshadabaiwan. Two novel er1 alleles were identified in Dabaiwandou and Guiwan 1, which were designated as er1-13 and er1-14, respectively. Both novel alleles were characterized with a 1-bp deletion (T) in positions 32 (exon 1) and 277 (exon 3), respectively, which caused a frame-shift mutation to result in premature termination of translation of PsMLO1 protein. The co-dominant functional markers specific for er1-13 and er1-14, KASPar-er1-13, and KASPar-er1-14 were developed and effectively validated in populations and pea germplasms. Here, two novel er1 alleles were characterized and their functional markers were validated. These results provide powerful tools for marker-assisted selection in pea breeding.
Lipidomics Profiling of Patients with Low Bone Mineral Density (LBMD)
Authors: Aleidi Shereen M. , Al-Ansari Mysoon M. , Alnehmi Eman A. , Malkawi Abeer K. , Alodaib Ahmad , Alshaker Mohamed , Benabdelkamel Hicham , Abdel Rahman Anas M.
Published: October 2022

The relationship between lipid metabolism and bone mineral density (BMD) is still not fully elucidated. Despite the presence of investigations using osteoporotic animal models, clinical studies in humans are limited. In this work, untargeted lipidomics profiling using liquid chromatography-mass spectrometry (LC-MS) analysis of human serum samples was performed to identify the lipidomics profile associated with low bone mineral density (LBMD), with a subsequent examination of potential biomarkers related to OP risk prediction or progression. A total of 69 participants were recruited for this cohort study, including the osteoporotic group (OP, n = 25), osteopenia group (ON, n = 22), and control (Ctrl, n = 22). The LBMD group included OP and ON patients. The lipidomics effect of confounding factors such as age, gender, lipid profile, body mass index (BMD), chronic diseases, and medications was excluded from the dataset. The results showed a clear group separation and clustering between LBMD and Ctrl (Q2 = 0.944, R2 = 0.991), indicating a significant difference in the lipids profile. In addition, 322 putatively identified lipid molecules were dysregulated, with 163 up- and 159 down-regulated in LBMD, compared with the Ctrl. The most significantly dysregulated subclasses were phosphatidylcholines (PC) (n = 81, 25.16% of all dysregulated lipids 322), followed by triacylglycerol (TG) (n = 65, 20.19%), and then phosphatidylethanolamine (PE) (n = 40, 12.42%). In addition, groups of glycerophospholipids, including LPC (7.45%), LPE (5.59%), and PI (2.48%) were also dysregulated as of LBMD. These findings provide insights into the lipidomics alteration involved in bone remodeling and LBMD. and may drive the development of therapeutic targets and nutritional strategies for OP management.
A Polysaccharide Isolated from the Herb Bletilla striata Combined with Methylcellulose to Form a Hydrogel via Self-Assembly as a Wound Dressing
Authors: Jakfar Subhaini , Lin Tzu-Chieh , Chen Zhi-Yu , Yang I-Hsuan , Gani Basri A. , Ningsih Diana Setya , Kusuma Hendra , Chang Chia-Tien , Lin Feng-Huei
Published: October 2022

The Bletilla striata Polysaccharide (BSP), a natural polysaccharide derived from the east Asian terrestrial orchid Bletilla striata, is an anti-inflammatory, antiviral, and antioxidant polysaccharide. Traditionally, it has been used to treat hemostasis and for wound healing. In this study, BSP was blended with methylcellulose (MC) and methylparaben (MP) to create a hydrogel through a self-assembly route as a wound dressing. The developed hydrogels were designed as M2Bx, M5Bx, and M8Bx. M stands for MC, and the number represents a percentage. Whereas the second letter of B stands for BSP, and x refers to the percentage variation of BSP: x = 0.5%, 1%, and 2%. All the developed MB hydrogels contained β-glucopyranosyl and α-mannopyranosyl, and rheology test had a tan δ value ≥ 0.5. The pore sizes of the hydrogels decreased by increasing the MC and BSP content, and they had better properties with respect to water loss and their swelling ratio. Evaluations in vitro and in vivo showed that all of the developed MB hydrogels have good cell viability and wound-healing properties. The M8B2 hydrogel group was found to be superior to the others from within the developed MB hydrogels. Therefore, we believe that the M8B2 hydrogel formulation has a high potential for development as a wound dressing.
Interacting with a Chatbot-Based Advising System: Understanding the Effect of Chatbot Personality and User Gender on Behavior
Authors: Kuhail Mohammad Amin , Thomas Justin , Alramlawi Salwa , Shah Syed Jawad Hussain , Thornquist Erik
Published: October 2022

Chatbots with personality have been shown to affect engagement and user subjective satisfaction. Yet, the design of most chatbots focuses on functionality and accuracy rather than an interpersonal communication style. Existing studies on personality-imbued chatbots have mostly assessed the effect of chatbot personality on user preference and satisfaction. However, the influence of chatbot personality on behavioral qualities, such as users’ trust, engagement, and perceived authenticity of the chatbots, is largely unexplored. To bridge this gap, this study contributes: (1) A detailed design of a personality-imbued chatbot used in academic advising. (2) Empirical findings of an experiment with students who interacted with three different versions of the chatbot. Each version, vetted by psychology experts, represents one of the three dominant traits, agreeableness, conscientiousness, and extraversion. The experiment focused on the effect of chatbot personality on trust, authenticity, engagement, and intention to use the chatbot. Furthermore, we assessed whether gender plays a role in students’ perception of the personality-imbued chatbots. Our findings show a positive impact of chatbot personality on perceived chatbot authenticity and intended engagement, while student gender does not play a significant role in the students’ perception of chatbots.
The Mu2e Crystal Calorimeter: An Overview
Authors: Atanov Nikolay , Baranov Vladimir , Borrel Leo , Bloise Caterina , Budagov Julian , Ceravolo Sergio , Cervelli Franco , Colao Francesco , Cordelli Marco , Corradi Giovanni , Davydov Yuri , Falco Stefano Di , Diociaiuti Eleonora , Donati Simone , Echenard Bertrand , Ferrari Carlo , Gioiosa Antonio , Giovannella Simona , Giusti Valerio , Glagolev Vladimir , Grancagnolo Francesco , Hampai Dariush , Happacher Fabio , Hitlin David , Martini Matteo , Middleton Sophie , Miscetti Stefano , Morescalchi Luca , Paesani Daniele , Pasciuto Daniele , Pedreschi Elena , Porter Frank , Raffaelli Fabrizio , Saputi Alessandro , Sarra Ivano , Spinella Franco , Taffara Alessandra , Zanetti Anna Maria , Zhu Ren Yuan
Published: October 2022

The Mu2e experiment at Fermilab will search for the standard model-forbidden, charged lepton flavour-violating conversion of a negative muon into an electron in the field of an aluminium nucleus. The distinctive signal signature is represented by a mono-energetic electron with an energy near the muon’s rest mass. The experiment aims to improve the current single-event sensitivity by four orders of magnitude by means of a high-intensity pulsed muon beam and a high-precision tracking system. The electromagnetic calorimeter complements the tracker by providing high rejection power in muon to electron identification and a seed for track reconstruction while working in vacuum in presence of a 1 T axial magnetic field and in a harsh radiation environment. For 100 MeV electrons, the calorimeter should achieve: (a) a time resolution better than 0.5 ns, (b) an energy resolution <10%, and (c) a position resolution of 1 cm. The calorimeter design consists of two disks, each loaded with 674 undoped CsI crystals read out by two large-area arrays of UV-extended SiPMs and custom analogue and digital electronics. We describe here the status of construction for all calorimeter components and the performance measurements conducted on the large-sized prototype with electron beams and minimum ionizing particles at a cosmic ray test stand. A discussion of the calorimeter’s engineering aspects and the on-going assembly is also reported.
Incremental Sheet Forming of Metal-Based Composites Used in Aviation and Automotive Applications
Authors: Trzepieciński Tomasz , Najm Sherwan Mohammed , Pepelnjak Tomaž , Bensaid Kamel , Szpunar Marcin
Published: October 2022

For several years, the aviation industry has seen dynamic growth in the use of composite materials due to their low weight and high stiffness. Composites are being considered as a means of building lighter, safer, and more fuel-efficient automobiles. Composite materials are the building material of a relatively new kind of unmanned aerial vehicle, commonly known as a drone. Incremental forming methods allow materials to be quickly formed without the need to manufacture conventional metal dies. Their advantage is the high profitability during the production of prototypes and a small series of products when compared with the conventional methods of plastic forming. This article provides an overview of the incremental forming capabilities of the more commonly produced aluminium- and titanium-based laminates, which are widely used in the aircraft industry. In addition, for composites that are not currently incrementally formed, i.e., aramid-reinforced aluminium laminates, the advantages and potential for incremental forming are presented.
Characterization of the Coralligenous Formations from the Marine Protected Area of Karaburun-Sazan, Albania
Authors: Gimenez Guadalupe , Corriero Giuseppe , Beqiraj Sajmir , Lazaj Lorela , Lazic Tamara , Longo Caterina , Mercurio Maria , Nonnis Marzano Carlotta , Zuccaro Massimo , Zuna Violeta , Pierri Cataldo
Published: October 2022

Coralligenous bioconstructions are one of the Mediterranean’s most distinctive and biodiverse marine habitats. This research aimed to provide a preliminary characterization of macrobenthic coralligenous assemblages at four sites located in the Marine National Park of Karaburun-Sazan in Albania. We analyzed images obtained from videos recorded along underwater transects at two different depths. Over a total of 61 taxa (3 Rhodophyta, 2 Ochrophyta, 6 Chlorophyta, 30 Porifera, 5 Cnidaria, 3 Mollusca, 2 Annelida, 1 Arthropoda, 4 Bryozoa, 4 Echinodermata, and 1 Chordata), 53 were identified at the species level using taxonomic and semi-quantitative video image analysis, thus allowing an update to the Albanian coralligenous species list with 34 new species. This study revealed differences in species richness and composition among the investigated sites and between depths, with a high number of taxa exclusive to one site and a few taxa common to all sites. Seven taxa are protected by law, among which are the echinoderm Centrostephanus longispinus, included in the Bern (Annex II) and Barcelona (Annex II) Conventions and Habitat Directive (92/43 EEC) (Annex IV), and the sponges Spongia (Spongia) officinalis and S. (S.) lamella, included in Annex III of the Bern Convention. Only the alga Caulerpa cylindracea can be considered an alien species. Although preliminary, the present research indicated the occurrence of rich and diversified macrobenthic assemblages in the study area. Moreover, it has been demonstrated that video analysis can provide a biodiversity baseline within MPAs, where traditional methods involving invasive sampling cannot be applied, particularly in areas such as the Albanian coasts, where anthropogenic impacts have been historically significant. Finally, this work provides a first estimate of the structural biodiversity in a recently established marine protected area, thus representing the basis for subsequent monitoring.
Three-to-One Internal Resonance of L-Shaped Multi-Beam Structure with Nonlinear Joints
Authors: Shi Yunxu , Wu Zhe , Liu Wei , Wei Jin
Published: October 2022

In this paper, a reduced-order analytical model for an L-shaped multi-beam structure with nonlinear joints is presented to investigate the nonlinear responses of the system with three-to-one internal resonances conditions. Firstly, the global mode shapes are used to obtain an explicit set of nonlinear ordinary differential equations of motion for the system. Then, the first two natural frequencies of the system are calculated to determine the specific tip mass that results in three-to-one internal resonance. Subsequently, an approximation of the analytical solution of the dynamic model with two-degree-of-freedom is derived by using the multi-scale method. The accuracy of the approximation solution is verified by comparing it with the numerical solution obtained from the original motion equations. Based on the nonlinear dynamical model obtained by this paper, the frequency response curves are given to investigate the nonlinear dynamic characteristic of the L-shaped multi-beam structure with nonlinear joints. The results show that the nonlinear stiffness of the joints has a great influence on the nonlinear response of the system with three-to-one internal resonance conditions.
Assessment of the Black Sea High-Altitude Wind Energy
Authors: Onea Florin , Manolache Alexandra Ionelia , Ganea Daniel
Published: October 2022

Airborne wind energy systems (AWESs) represent a novel idea that aims to gather energy from stronger winds aloft while operating at altitudes above conventional wind turbines (WTs). For this study, we examined the wind resources at a height of 100 m available for traditional wind turbines with aerial wind energy technologies, in addition to the wind potential at higher altitudes up to 500 m. The considered period was 20 years from January 2002 to December 2020, and the data were extracted from the ERA5 reanalysis database. We studied the possibility of placing 500 kW and 5 MW airborne systems in the Black Sea and the Azov Sea and compared them with a conventional turbine. As expected, the western part of the Black Sea presented the best results, both for the 500 kW airborne system with an annual energy production (AEP) of 2.39 GWh and a capacity factor of 55%, and for the 5 MW airborne system, which has an annual electricity production of 15.81 GWh and a capacity factor of 36%. Better results were recorded for the Sea of Azov for both the 500 kW and the 5 MW airborne systems, with an AEP of 2.5 and 15.81 GWh and a capacity factor of 58% and 36%, respectively.
What Do We Know about Crowdfunding and P2P Lending Research? A Bibliometric Review and Meta-Analysis
Authors: Rabbani Mustafa Raza , Bashar Abu , Hawaldar Iqbal Thonse , Shaik Muneer , Selim Mohammed
Published: October 2022

In the era of fintech, businesses using technology other than traditional banks are providing financial services. Crowdfunding and peer-to-peer (P2P) lending are two of the most exciting financial innovations of the twenty-first century. In this paper, we use a bibliometric review and meta-analysis to understand the academic research on crowdfunding and P2P lending. Our findings show that the research on this topic has grown a lot in terms of publications since 2013 and the maximum mean total citations were observed in the year 2014. We provide the details about the most influential authors based on total citations, authors with the greatest number of publications, the most influential documents, significant journal sources, highest single country production, multiple country production, and important affiliations. We further apply the network analysis and visualisation techniques wherein we provide the details of the citation analysis of documents, co-citation analysis of authors, and co-occurrence analysis of author keywords. Finally, we provide the future directions of the research on this burgeoning topic.
Assessing the Area of Suitable Land for Climate Change Mitigation with Sitka Spruce (Picea sitchensis) in Scotland
Authors: Abimbola Ismaila , Feliciano Diana
Published: October 2022

One of the key areas in which the United Kingdom government plans to achieve net zero, reduce GHG emissions and sequester carbon is through afforestation. Afforestation will also provide ecosystem services to society. The Scottish government’s target is to increase woodland cover in Scotland to 25% by 2050. In this study, a land suitability analysis was used to investigate the likelihood of achieving this target based on the biophysically suitable and available land considering the current policy constraints for planting Sitka spruce (Picea sitchensis) in Scotland. The results showed that about 19% of land area in Scotland is biophysically suitable for Sitka spruce and about 13% is biophysically suitable and available based on policy constraints. Thus, there is an opportunity for the Scottish government to increase the woodland cover in Scotland to 31.5% and exceed its 25% woodland target. However, for Scotland to achieve net zero by 2045, it will require that more trees be planted on higher-quality agricultural land, different from areas where trees are currently planted.
Shakespeare’s Ambivalence: Epistemological Hesitation about the Origin of Evil
Authors: Montague Tee
Published: October 2022

Recent studies of the conceptualization of the Devil in the early modern period have pointed to the shifting theological and philosophical coordinates, which made possible a diverse spectrum of representation of diabolical evil—from Francis Bacon’s naturalistic scepticism to King James’s supernatural demonology. Shakespeare has always been central to this discussion but has not yet been placed in a contextual frame that incorporates the rise of scholarly interest in the diabolical. This article interprets Shakespeare’s representation of diabolical evil in Hamlet (1601), Othello (1603), Measure for Measure (1604) and Macbeth (1606) as constituted by a complex tension between natural and supernatural ideas about the origin of evil. Drawing on a raft of recent scholarship on representations of witchcraft and devils in the period, I show that diabolical figures in the universe of Shakespeare during the period of great tragedies between 1601 to 1606 exist in two modes of representation: as a persistent magical ambience and as a localized agent. Ambivalence is expressed in the hesitation between these opposing theological modes and is evident in the way that the Devil’s material agency is obscured and left unresolved. Viewing this through the lens of the fantastic as an ontological uncertainty that results in epistemological hesitation helps us to frame Shakespeare’s ambivalence, which at least in part originates in the ambivalent theology of Calvin. The analysis thereby positions hesitation and diabolic temptation in line with Calvin’s theology and shows how Calvin’s framework of secular evil presents an intellectual context through which Shakespeare’s ambiguity can be understood in theological terms.
Upgrade of Biaxial Mechatronic Testing Machine for Cruciform Specimens and Verification by FEM Analysis
Authors: Miková Ľubica , Prada Erik , Kelemen Michal , Krys Václav , Mykhailyshyn Roman , Sinčák Peter Ján , Merva Tomáš , Leštach Lukáš
Published: October 2022

This article deals with the modernization of an existing loading system for the analysis of elastic–plastic properties of sheet metals in plane stress. The identification of the beginning of plastic deformation of sheet metal in plane strain is important in the cold pressing of sheet metal and in the assessment of the load capacity of thin-walled structures in the automotive and aerospace industry. The design of the control structure of the hydraulic part of the loading system for cross testing was carried out to automatize the whole process of experimental evaluation. For this purpose, proportional pressure-reducing valves together with control electronics were designed. Thus, the loading system is a control system for which a control algorithm has been designed and implemented on a PC. A computer simulation was performed to verify the functionality of the load system. An FEM simulation was performed to verify the correctness of the proposed numerical models and to confirm the experimental results. A numerical nonlinear model of the selected material was applied for the specification of plastic deformations. From the results, it is possible to state the appropriateness of the used models as well as the appropriateness of using modernized equipment for subsequent analysis of the plastic deformation of cruciform specimens.
Experimental Investigation on Combustion and Performance of Diesel Engine under High Exhaust Back Pressure
Authors: Huang Li , Liu Junjie , Liu Rui , Wang Yang , Liu Long
Published: October 2022

The use of exhaust gas recirculation, complex after-treatment systems, advanced technology of high-strength engines, and underwater exhaust will lead to increased diesel exhaust back pressure (EBP). This will increase the residual exhaust gas and the exchange temperature in the cylinder and reduce the fresh air charged in the next cycle. In this work, the effects of two high EBP conditions (10 kPa and 25 kPa) on the performance of medium-speed ship engines under different loads are explored through experiments. The results show that the increase in EBP from 10 kPa to 25 kPa has little effect on the heat release rate, engine power, and engine start-up time. However, it will lead to ignition advance and the maximum pressure rise rate, peak pressure, and exhaust temperature increase. The increase in EBP has a more significant impact on the small valve overlap angle. Because the reduction in the valve overlap angle has led to an increase in the residual exhaust gas, further increases in EBP causes residual exhaust gas effects to be more pronounced. The effect of increasing EBP on fuel consumption depends primarily on which effect of exhaust back pressure on temperature and fresh air intake dominates.
On Strictly Positive Fragments of Modal Logics with Confluence
Authors: Kikot Stanislav , Kudinov Andrey
Published: October 2022

We axiomatize strictly positive fragments of modal logics with the confluence axiom. We consider unimodal logics such as K.2, D.2, D4.2 and S4.2 with unimodal confluence ⋄□p→□⋄p as well as the products of modal logics in the set K,D,T,D4,S4, which contain bimodal confluence ⋄1□2p→□2⋄1p. We show that the impact of the unimodal confluence axiom on the axiomatisation of strictly positive fragments is rather weak. In the presence of ⊤→⋄⊤, it simply disappears and does not contribute to the axiomatisation. Without ⊤→⋄⊤ it gives rise to a weaker formula ⋄⊤→⋄⋄⊤. On the other hand, bimodal confluence gives rise to more complicated formulas such as ⋄1p∧⋄2n⊤→⋄1(p∧⋄2n⊤) (which are superfluous in a product if the corresponding factor contains ⊤→⋄⊤). We also show that bimodal confluence cannot be captured by any finite set of strictly positive implications.
Testing the Resource Hypothesis of Species–Area Relationships: Extinction Cannot Work Alone
Authors: Deng Wei , Liu Li-Lei , Yu Guo-Bin , Li Na , Yang Xiao-Yan , Xiao Wen
Published: October 2022

The mechanisms that underpin the species–area relationship (SAR) are crucial for both the development of biogeographic theory and the application of biodiversity conservation. Since its origin, the resource hypothesis, which proposes that rich resources in vast ecosystems will lower extinction rates and shape the SAR, has not been tested. The impossibility to quantify resources and extinction rates using plants and animals as research subjects, as well as the inability to rule out the influences of the area per se, habitat diversity, dispersal, and the historical background of biodiversity, make testing this hypothesis problematic. To address these challenges and test this hypothesis, two sets of microbial microcosm experimental systems with positive and negative correlated resources and volumes were created in this work. The results of 157 high-throughput sequencing monitoring sessions at 11 time points over 30 consecutive days showed that neither of the experimental groups with positive or negative correlations between total resources and microcosm volume had a significant SAR, and there were no negative correlations between extinction rates and resources. Therefore, in our microcosmic system, resources do not influence extinction rates or shape the SAR. Dispersal should be the principal mode of action if the resource theory is correct.
Simple Enzyme Immobilization for Flow Chemistry? An Assessment of Available Strategies for an Acetaldehyde-Dependent Aldolase
Authors: Wäscher Martin , Classen Thomas , Pietruszka Jörg
Published: October 2022

Enzyme immobilization is a technology that enables (bio-)catalysts to be applied in continuous-flow systems. However, there is a plethora of immobilization methods available with individual advantages and disadvantages. Here, we assessed the influence of simple and readily available methods with respect to the performance of 2-deoxy-d-ribose-5-phosphate aldolase (DERA) in continuous-flow conditions. The investigated immobilization strategies cover the unspecific attachment to carriers via epoxides, affinity-based attachment via metal ion affinity, StrepTag™-StrepTactin™ interaction as well as the covalent affinity attachment of an enzyme to a matrix tethered by the HaloTag®. The metal-ion-affinity-based approach outperformed the other methods in terms of immobilized activity and stability under applied conditions. As most enzymes examined today already have a HisTag for purification purposes, effective immobilization may be applied, as simple as a standard purification, if needed.
Metallo-Drugs in Cancer Therapy: Past, Present and Future
Authors: Lucaciu Roxana Liana , Hangan Adriana Corina , Sevastre Bogdan , Oprean Luminița Simona
Published: October 2022

Cancer treatments which include conventional chemotherapy have not proven very successful in curing human malignancies. The failures of these treatment modalities include inherent resistance, systemic toxicity and severe side effects. Out of 50% patients administrated to chemotherapy, only 5% survive. For these reasons, the identification of new drug designs and therapeutic strategies that could target cancer cells while leaving normal cells unaffected still continues to be a challenge. Despite advances that have led to the development of new therapies, treatment options are still limited for many types of cancers. This review provides an overview of platinum, copper and ruthenium metal based anticancer drugs in clinical trials and in vitro/in vivo studies. Presumably, copper and ruthenium complexes have greater potential than Pt(II) complexes, showing reduced toxicity, a new mechanism of action, a different spectrum of activity and the possibility of non-cross-resistance. We focus the discussion towards past, present and future aspects.
Involvement of Arsenic Atom of AsF3 in Five Pnicogen Bonds: Differences between X-ray Structure and Theoretical Models
Authors: Scheiner Steve , Michalczyk Mariusz , Zierkiewicz Wiktor
Published: October 2022

Bonding within the AsF3 crystal is analyzed via quantum chemical methods so as to identify and quantify the pnicogen bonds that are present. The structure of a finite crystal segment containing nine molecules is compared with that of a fully optimized cluster of the same size. The geometries are qualitatively different, with a much larger binding energy within the optimized nonamer. Although the total interaction energy of a central unit with the remaining peripheral molecules is comparable for the two structures, the binding of the peripherals with one another is far larger in the optimized cluster. This distinction of much stronger total binding within the optimized cluster is not limited to the nonamer but repeats itself for smaller aggregates as well. The average binding energy of the cluster rises quickly with size, asymptotically approaching a value nearly triple that of the dimer.
Allogeneic Bone Impregnated with Biodegradable Depot Delivery Systems for the Local Treatment of Joint Replacement Infections: An In Vitro Study
Authors: Prokes Libor , Snejdrova Eva , Soukup Tomas , Malakova Jana , Frolov Vladislav , Loskot Jan , Andrys Rudolf , Kucera Tomas
Published: October 2022

Although progress is evident in the effective treatment of joint replacement-related infections, it still remains a serious issue in orthopedics. As an example, the local application of antibiotics-impregnated bone grafts supplies the high drug levels without systemic side effects. However, antibiotics in the powder or solution form could be a risk for local toxicity and do not allow sustained drug release. The present study evaluated the use of an antibiotic gel, a water-in-oil emulsion, and a PLGA microparticulate solid dispersion as depot delivery systems impregnating bone grafts for the treatment of joint replacement-related infections. The results of rheological and bioadhesive tests revealed the suitability of these formulations for the impregnation of bone grafts. Moreover, no negative effect on proliferation and viability of bone marrow mesenchymal stem cells was detected. An ex vivo dissolution test of vancomycin hydrochloride and gentamicin sulphate from the impregnated bone grafts showed a reduced burst and prolonged drug release. The PLGA-based formulation proved to be particularly promising, as one-day burst release drugs was only 15% followed with sustained antibiotics release with zero-order kinetics. The results of this study will be the basis for the development of a new product in the Tissue Section of the University Hospital for the treatment of bone defects and infections of joint replacements.
Antioxidant and Antimicrobial Activities of Thai Edible Plant Extracts Prepared Using Different Extraction Techniques
Authors: Junsathian Pimmada , Nakamura Soichiro , Katayama Shigeru , Rawdkuen Saroat
Published: October 2022

This study investigated the antioxidant and antimicrobial activities of six Thai edible plant leaf extracts, including Cashew (CN), Chamuang (CM), Monpu (MP), Thurianthet (TT), Kradon (KD) and Pakliang (PL), extracted using ethanol extraction (EE), microwave-assisted extraction (MAE), and ultrasonic-assisted extraction (UAE). The leaf extracts were characterized for percentage yield, total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and-ferric reducing antioxidant power (FRAP) activity, and antimicrobial activity against spoilage. MAE produced the highest percentage yields, among which MAE-extracted MP exhibited the highest yield. Furthermore, the highest TPC and TFC were obtained for MAE, with MAE-extracted KD and CN showing the highest TPC and TFC, respectively, among the samples. The highest DPPH and FRAP values were seen in MAE-processed CN, KD, and MP extracts. The inhibition zone of pathogenic bacteria, minimum inhibitory concentration, and minimum bacterial concentration were determined in all samples except TT. These findings indicate that, compared to EE and UAE, MAE improved the antioxidant and antimicrobial efficacy of the leaf extracts. The aforementioned extracts could be employed as natural food additives to prevent chemical and microbial spoilage of foods.
Effect of Hydrophilic Polymers on the Release Rate and Pharmacokinetics of Acyclovir Tablets Obtained by Wet Granulation: In Vitro and In Vivo Assays
Authors: Venkatesh D. Nagasamy , Meyyanathan Subramanianainar N. , Kovacevic Andjelka , Zielińska Aleksandra , Fonseca Joel , Eder Piotr , Dobrowolska Agnieszka , Souto Eliana B.
Published: October 2022

This study aims to evaluate the feasibility of producing acyclovir-containing modified release matrix tablets by a wet granulation method based on the type and concentration of two pharmaceutical-grade hydrophilic matrix polymers (i.e., hydroxypropyl methylcellulose (HPMC), carbomers, and their combinations) commonly used in biomedical applications. The mechanical properties of the tablets and in vitro and in vivo performance were studied. The physicochemical properties of the raw materials and corresponding physical mixtures were characterized by differential scanning calorimetry, showing that the hydrophilic polymers did not influence the physicochemical properties of the drug. The wet granulation process improved the flow and compression properties of the obtained granules. This method enabled the preparation of the matrix tablets of acyclovir with appropriate mechanical properties concerning hardness and friability. The drug release kinetics was governed by the type and concentration of the hydrophilic polymers composing the matrices. The study has proven that HPMC-composed tablets were superior in modified drug release properties compared to carbomer- and HPMC/carbomer-based tablets. Mathematical analysis of the release profiles, determined in a medium adjusted to pH 1.2 followed by pH 7.4, revealed that the drug released from the hydrophilic tablets followed non-Fickian first-order kinetics. An optimal HPMC-based formulation submitted to accelerated stability studies (40 °C, 75% RH) was stable for three months. A complete cross-over bioavailability study of the selected acyclovir-loaded sustained release tablets and marketed immediate-release tablets were compared in six healthy male volunteers. The extent of drug absorption from the sustained release tablets was significantly greater than that from immediate-release pills, which may improve the drug’s antiviral properties attributed to the lower elimination rate and enhanced acyclovir half-life.
Synthesis, Docking Studies and Pharmacological Evaluation of Serotoninergic Ligands Containing a 5-Norbornene-2-Carboxamide Nucleus
Authors: Sparaco Rosa , Kędzierska Ewa , Kaczor Agnieszka A. , Bielenica Anna , Magli Elisa , Severino Beatrice , Corvino Angela , Gibuła-Tarłowska Ewa , Kotlińska Jolanta H. , Andreozzi Giorgia , Luciano Paolo , Perissutti Elisa , Frecentese Francesco , Casertano Marcello , Leśniak Anna , Bujalska-Zadrożny Magdalena , Oziębło Małgorzata , Capasso Raffaele , Santagada Vincenzo , Caliendo Giuseppe , Fiorino Ferdinando
Published: October 2022

A new series of 5-norbornene-2-carboxamide derivatives was prepared and their affinities to the 5-HT1A, 5-HT2A, and 5-HT2C receptors were evaluated and compared to a previously synthesized series of derivatives characterized by exo-N-hydroxy-5-norbornene-2,3-dicarboximidenucleus, in order to identify selective ligands for the above-mentioned subtype receptors. Arylpiperazines represents one of the most important classes of 5-HT1AR ligands, and recent research concerning new derivatives has been focused on the modification of one or more portions of such pharmacophore. The combination of structural elements (heterocyclic nucleus, propyl chain and 4-substituted piperazine), known to be critical to the affinity to 5-HT1A receptors, and the proper selection of substituents led to compounds with high specificity and affinity towards serotoninergic receptors. The most active compounds were selected for further in vivo assays to determine their functional activity. Finally, to rationalize the obtained results, molecular docking studies were performed. The results of the pharmacological studies showed that Norbo-4 and Norbo-18 were the most active and promising derivatives for the serotonin receptor considered in this study.
From Tradition to Health: Chemical and Bioactive Characterization of Five Traditional Plants
Authors: Garcia-Oliveira Paula , Carreira-Casais Anxo , Pereira Eliana , Dias Maria Inês , Pereira Carla , Calhelha Ricardo C. , Stojković Dejan , Sokovic Marina , Simal-Gandara Jesus , Prieto Miguel A. , Caleja Cristina , Barros Lillian
Published: October 2022

Several scientific studies have been proving the bioactive effects of many aromatic and medicinal plants associated with the presence of a high number of bioactive compounds, namely phenolic compounds. The antioxidant, anti-inflammatory, and antimicrobial capacities of these molecules have aroused high interest in some industrial sectors, including food, pharmaceuticals, and cosmetics. This work aimed to determine the phenolic profiles of the infusions and hydroethanolic extracts of five plants (Carpobrotus edulis, Genista tridentata, Verbascum sinuatum, Cytisus multiflorus, and Calluna vulgaris) that have been employed in many traditional preparations. In addition, the antioxidant, antimicrobial, anti-inflammatory, and anti-tumoral activity of each different preparation was evaluated using in vitro assays. The HPLC-DAD-ESI/MS profile revealed the presence of eighty phenolic compounds, belonging to seven different families of compounds. Regarding antioxidant properties, the hydroethanolic extract of C. edulis showed a potent effect in the TBARS assay (IC50 = 1.20 µg/mL), while G. tridentata hydroethanolic extract achieved better results in the OxHLIA test (IC50 = 76 µg/mL). For cytotoxic and anti-inflammatory results, V. sinuatum infusions stood out significantly, with GI50 = 59.1–92.1 µg/mL and IC50 = 121.1 µg/mL, respectively. Finally, C. edulis hydroethanolic extract displayed the most relevant antibacterial activity, showing MBC values of 0.25–1 mg/mL, while G. tridentata hydroethanolic extract exerted the greatest antifungal effects (MFC of 0.5–1 mg/mL). The results of this study deepen the knowledge of the phenolic profiles and also provide evidence on the bioactive properties of the species selected, which could be considered highly valuable options for research and application in several sectors, namely food, cosmetics, and pharmaceuticals.
Barium Titanate Functionalization with Organosilanes: Effect on Particle Compatibility and Permittivity in Nanocomposites
Authors: Zamperlin Nico , Bottacini Andrea , Callone Emanuela , Pegoretti Alessandro , Fontana Marco , Dirè Sandra
Published: October 2022

Barium titanate (BT) recently gained new interest in the preparation of dielectric and piezoelectric lead-free materials for applications in sensors, electronics, energy harvesting and storage fields. Barium titanate nanocomposites can achieve attractive performance, provided that the compatibility between ceramic particles and polymeric matrices is enhanced to the benefit of the physical properties of the final composite. Tuning the particle–matrix interface through particle functionalization represents a viable solution. In this work, surface functionalization of BT nanoparticles (NPs), obtained by hydrothermal synthesis, with 3-glycidyloxypropyltrimethoxysilane, 2-[(acetoxy(polyethyleneoxy)propyl]triethoxysilane and triethoxysilylpropoxy(polyethyleneoxy)dodecanoate, was performed after optimizing the hydroxylation process of the NPs to improve their surface reactivity and increase the yield of grafting. Solid-state nuclear magnetic resonance and thermogravimetric analysis were used to quantify the molecules grafted onto the ceramic nanoparticles. Both bare and functionalized particles were employed in the realization of epoxy- and polydimethylsiloxane (PDMS)-based nanocomposites. Functionalization was proven to be beneficial for particle dispersibility and effective for particle alignment in the PDMS matrix. Moreover, the dielectric constant measurements revealed the potential of PDMS-based nanocomposites for applications in the field of dielectric elastomers.