bluuebunny/crossref_metadata_2025 huggingface dataset:
Rheological Properties of Industrial Hot Trub
Authors: Stachnik Marta , Sterczyńska Monika , Smarzewska Emilia , Ptaszek Anna , Piepiórka-Stepuk Joanna , Ageev Oleg , Jakubowski Marek
Published: December 2021

The boiling of beer wort with hops results in the formation of a hot trub, a sediment consisting mainly of water-insoluble tannin and protein conglomerates and hop residue. Hot trub is a waste product, removed in a clarifying tank and discarded. The use of barley malt substitutes in recipes for beer is associated with an increase in the amount of generated hot trub. In presented study, an analysis of the rheological properties of industrial hot trub was carried out. Samples varied with regard to the quantities of unmalted barley (0%, 35%, and 45%) and worts’ extract (12.5, 14.1, 16.1, and 18.2 °Plato) in the recipe. The rheology of each type of sludge was determined using a hysteresis loop at four different temperatures. The results showed the shear-thinning and thixotropic properties of the hot trub. It was found that, regardless of the raw material and extract used, all samples exhibited the same rheological properties, but with different values. It was also proved that both raw material composition and temperature affected the hot trub’s rheology. The highest values of viscosity were identified for malted barley, whereas the lowest apparent viscosity values were recorded for the hot trub with a 30% addition of unmalted barley. The Herschel–Bulkley model had the best fit to the experimental data.
Study of an Ecological Cement-Based Composite with a Sustainable Raw Material, Sunflower Stalk Ash
Authors: Șerbănoiu Adrian Alexandru , Grădinaru Cătălina Mihaela , Cimpoeșu Nicanor , Filipeanu Dumitru , Șerbănoiu Bogdan Vasile , Cherecheș Nelu Cristian
Published: December 2021

The use of plant ash as a sustainable cementitious material in concrete composition is a widely researched subject in the construction domain. A plant studied so far more for its thermal insulation properties, sunflower, was analyzed in this study with regard to its ash effects on the concrete composition. The present research aimed to analyze the effects of a 2.5%, 5%, 7.5%, 10%, 15%, 20%, or 30% volume replacement of cement by sunflower stalk ash (SA), a sustainable cementitious material, on the concrete compressive strength at 28 days and three months, the flexural and splitting tensile strengths, the resistance to repeated freeze–thaw cycles, and the resistance to chemical attack of hydrochloric acid. The elementary chemical composition of the SA and the composites was included also. According to the experimental results, SA decreased the values of the compressive and tensile strength of the concrete, but it improved the concrete behavior under repeated freeze–thaw cycles and under the action of hydrochloric acid. A percent of 10% of SA led to a much more pronounced development of compressive strength over time than conventional concrete (26.6% versus 12%).
Mutual Effects of Components of Protective Films Applied on Steel in Octadecylamine and 1,2,3-Benzotriazole Vapors
Authors: Luchkin Andrey Y. , Goncharova Olga A. , Andreeva Nina P. , Kasatkin Vadim E. , Vesely Sergey S. , Kuznetsov Yurii I. , Andreev Nikolay N.
Published: December 2021

In this work, we used a combination of corrosion, electrochemical, and physical methods to determine the properties of nanoscale films obtained by treatment with octadecylamine (ODA), benzotriazole (BTA) vapors, and their mixtures at elevated temperatures. The mixture of ODA + BTA surpasses its components in protective aftereffect, but an analysis of their mutual effects shows that there is antagonism between them. Electrochemical impedance spectroscopy data indicate that the protection of steel by a mixture of ODA + BTA and its components is characterized by a mixed blocking activation mechanism. The processing of steel in hot vapors of the ODA + BTA mixture leads to hydrophobization of the surface and super-hydrophobization if a polymodal surface is created on the steel before processing in vapors.
Optical Measurements and Theoretical Modelling of Excitons in Double ZnO/ZnMgO Quantum Wells in an Internal Electric Field
Authors: Andrzejewski Janusz , Pietrzyk Mieczyslaw Antoni , Jarosz Dawid , Kozanecki Adrian
Published: December 2021

In this paper, the photoluminescence spectra of excitons in ZnO/ZnMgO/ZnO double asymmetric quantum wells grown on a–plane Al2O3 substrates with internal electric-field bands structures were studied. In these structures, the electron and the hole in the exciton are spatially separated between neighbouring quantum wells, by a ZnMgO barrier with different thickness. The existence of an internal electric field generates a linear potential and, as a result, lowers the energy of quantum states in the well. For the wide wells, the electrons are spatially separated from the holes and can create indirect exciton. To help the understanding of the photoluminescence spectra, for single particle states the 8 k·p for wurtzite structure is employed. Using these states, the exciton in the self-consistent model with 2D hydrogenic 1s–like wave function is calculated.
Reaction Model Taking into Account the Catalyst Morphology and Its Active Specific Surface in the Process of Catalytic Ammonia Decomposition
Authors: Arabczyk Walerian , Pelka Rafał , Jasińska Izabella , Lendzion-Bieluń Zofia
Published: December 2021

Iron catalysts for ammonia synthesis/nanocrystalline iron promoted with oxides of potassium, aluminum and calcium were characterized by studying the nitriding process with ammonia in kinetic area of the reaction at temperature of 475 °C. Using the equations proposed by Crank, it was found that the process rate is limited by diffusion through the interface, and the estimated value of the nitrogen diffusion coefficient through the boundary layer is 0.1 nm2/s. The reaction rate can be described by Fick’s first equation. It was confirmed that nanocrystallites undergo a phase transformation in their entire volume after reaching the critical concentration, depending on the active specific surface of the nanocrystallite. Nanocrystallites transform from the α-Fe(N) phase to γ’-Fe4N when the total chemical potential of nitrogen compensates for the transformation potential of the iron crystal lattice from α to γ; thus, the nanocrystallites are transformed from the smallest to the largest in reverse order to their active specific surface area. Based on the results of measurements of the nitriding rate obtained for the samples after overheating in hydrogen in the temperature range of 500–700 °C, the probabilities of the density of distributions of the specific active surfaces of iron nanocrystallites of the tested samples were determined. The determined distributions are bimodal and can be described by the sum of two Gaussian distribution functions, where the largest nanocrystallite does not change in the overheating process, and the size of the smallest nanocrystallites increases with increasing recrystallization temperature. Parallel to the nitriding reaction, catalytic decomposition of ammonia takes place in direct proportion to the active surface of the iron nanocrystallite. Based on the ratio of the active iron surface to the specific surface, the degree of coverage of the catalyst surface with the promoters was determined.
Dilatometric Analysis and Kinetics Research of Martensitic Transformation under a Temperature Gradient and Stress
Authors: Liu Liheng , Guo Bin
Published: December 2021

Based on material constitutive models and the classic Koistinen–Marburger (KM) kinetics model, a new dilatometric analysis model was developed to extract the kinetics curve of martensitic transformation under a temperature gradient and stress from the measured dilatometric data and to determine the transformation parameters. The proposed dilatometric analysis model is generally for athermal martensitic transformation, relying only on the average atom volume of martensite and austenite. Furthermore, through theoretical calculations, the proposed model also provided a more accurate method for obtaining the martensite start temperature, which is different from the traditional method. According to the dilatometric analysis results for the martensitic transformation of a type of high-strength low-alloy steel, and the thermodynamic basis of martensitic transformation, a refined kinetics model was developed that successfully predicted the martensitic transformation kinetics curves under different stresses, taking into account the physical significance of the transformation parameter α and the driving force of stress for martensitic transformation.
The Effect of Implant Length and Diameter on Stress Distribution around Single Implant Placement in 3D Posterior Mandibular FE Model Directly Constructed Form In Vivo CT
Authors: Shinya Akikazu , Ishida Yoshiki , Miura Daisuke , Shinya Akiyoshi
Published: December 2021

A three-dimensional (3D) finite element (FE) model of the mandibular bone was created from 3D X-ray CT scan images of a live human subject. Simulating the clinical situation of implant therapy at the mandibular first molar, virtual extraction of the tooth was performed at the 3D FE mandibular model, and 12 different implant diameters and lengths were virtually inserted in order to carry out a mechanical analysis. (1) High stress concentration was found at the surfaces of the buccal and lingual peri-implant bone adjacent to the sides of the neck in all the implants. (2) The greatest stress value was approximately 6.0 MPa with implant diameter of 3.8 mm, approx. 4.5 MPa with implant diameter of 4.3 mm, and approx. 3.2 MPa with implant diameter of 6.0 mm. (3) The stress on the peri-implant bone was found to decrease with increasing length and mainly in diameter of the implant.
A Hybrid Grey Wolf Optimizer for Process Planning Optimization with Precedence Constraints
Authors: Milosevic Mijodrag , Cep Robert , Cepova Lenka , Lukic Dejan , Antic Aco , Djurdjev Mica
Published: December 2021

Process planning optimization is a well-known NP-hard combinatorial problem extensively studied in the scientific community. Its main components include operation sequencing, selection of manufacturing resources and determination of appropriate setup plans. These problems require metaheuristic-based approaches in order to be effectively and efficiently solved. Therefore, to optimize the complex process planning problem, a novel hybrid grey wolf optimizer (HGWO) is proposed. The traditional grey wolf optimizer (GWO) is improved by employing genetic strategies such as selection, crossover and mutation which enhance global search abilities and convergence of the traditional GWO. Precedence relationships among machining operations are taken into account and precedence constraints are modeled using operation precedence graphs and adjacency matrices. Constraint handling heuristic procedure is adopted to move infeasible solutions to a feasible domain. Minimization of the total weighted machining cost of a process plan is adopted as the objective and three experimental studies that consider three different prismatic parts are conducted. Comparative analysis of the obtained cost values, as well as the convergence analysis, are performed and the HGWO approach demonstrated effectiveness and flexibility in finding optimal and near-optimal process plans. On the other side, comparative analysis of computational times and execution times of certain MATLAB functions showed that the HGWO have good time efficiency but limited since it requires more time compared to considered hybrid and traditional algorithms. Potential directions to improving efficiency and performances of the proposed approach are given in conclusions.
Utilization of Crushed Pavement Blocks in Concrete: Assessment of Functional Properties and Environmental Impacts
Authors: Kočí Václav , Kočí Jan , Fořt Jan , Fiala Lukáš , Šál Jiří , Hager Izabela , Černý Robert
Published: December 2021

Production of concrete is connected to extensive energy demands, greenhouse gases production or primary sources depletion. Reflecting current economical, social, or environmental trends, there is strong pressure on mitigation these requirements and impacts. The exploitation of secondary- or waste materials in production processes has therefore a great potential which is not related solely to binders but also to fillers. In this light, this paper aims at thorough investigations of concrete mixtures with crushed concrete pavements as partial or full replacement of natural coarse aggregates. The research combines experimental techniques to quantify the influence of the substitution on basic physical, mechanical, and heat/moisture transport/storage parameters. The experimental data obtained are further exploited as input data for computational prediction of coupled heat and moisture transport to assess the influence of the aggregates substitution on hygrothermal performance of the built-in concretes. In the last step, the environmental impacts are assessed. Since the changes in the hygrothermal performance were found to be insignificant (i), the compressive strength were improved by up to 25% (ii) and most of the environmental impact indicators were decreased (iii) at the same time, the findings of the research presented predeterminate such a reuse strategy to wider application and use.
The Effects of Absorbing Materials on the Homogeneity of Composite Heating by Microwave Radiation
Authors: Nuhiji Betime , Bower Matthew P. , Proud William A. E. , Burpo Steven J. , Day Richard J. , Scaife Richard J. , Swait Timothy
Published: December 2021

When cured in a microwave, flat thin composite panels can experience even heat distribution throughout the laminate. However, as load and geometric complexity increase, the electromagnetic field and resulting heat distribution is altered, making it difficult to cure the composite homogeneously. Materials that absorb and/or reflect incident electromagnetic radiation have the potential to influence how the field behaves, and therefore to tailor and improve the uniformity of heat distribution. In this study, an absorber was applied to a composite with non-uniform geometry to increase heating in the location which had previously been the coldest position, transforming it into the hottest. Although this result overshot the desired outcome of temperature uniformity, it shows the potential of absorbing materials to radically change the temperature distribution, demonstrating that with better regulation of the absorbing effect, a uniform temperature distribution is possible even in non-uniform composite geometries.
Refractive Index of Heavily Germanium-Doped Gallium Nitride Measured by Spectral Reflectometry and Ellipsometry
Authors: Schiavon Dario , Mroczyński Robert , Kafar Anna , Kamler Grzegorz , Levchenko Iryna , Najda Stephen , Perlin Piotr
Published: December 2021

Gallium nitride (GaN) doped with germanium at a level of 1020 cm−3 is proposed as a viable material for cladding layers in blue- and green-emitting laser diodes. Spectral reflectometry and ellipsometry are used to provide evidence of a reduced index of refraction in such layers. The refractive-index contrast to undoped GaN is about 0.990, which is comparable to undoped aluminium gallium nitride (AlGaN) with an aluminium composition of 6%. Germanium-doped GaN layers are lattice-matched to native GaN substrates; therefore, they introduce no strain, cracks, and wafer bowing. Their use, in place of strained AlGaN layers, will enable significant improvements to the production process yield.
Inhibitory Effect of Astaxanthin on Testosterone-Induced Benign Prostatic Hyperplasia in Rats
Authors: Wang Liping , Hou Yiwen , Wang Rong , Pan Qi , Li Debao , Yan Han , Sun Zuyue
Published: December 2021

This study investigates the inhibitory effect of astaxanthin (AST) on testosterone-induced benign prostatic hyperplasia (BPH) in rats. Except for the sham operation, BPH model rats were randomly assigned to five groups: the BPH model control rats, AST-treated BPH model rats (20 mg/kg, 40 mg/kg, and 80 mg/kg), and epristeride (EPR)-treated BPH model rats. After treatment, as compared with the BPH model control rats, the prostate and ventral prostate weights of the AST-treated rats decreased, while there was a marked decline in the 80 mg/kg AST-treated rats. The same effect was also observed in the prostate index and ventral prostate index. The proliferation characteristics of epithelia observed in the BPH model control group were gradually alleviated in the AST-treated rats. As compared with the BPH model control rats, lower epithelial thicknesses of prostates and fewer secretory granules in epithelia were observed in the AST-treated rats. The superoxide dismutase (SOD) activity of prostates increased in all the AST-treated rats with a significant increase in the 40 mg/kg and 80 mg/kg AST-treated rats. The testosterone (T) and dihydrotestosterone (DHT) levels of prostates in the AST-treated groups were lower than those in the BPH model control group, and a significant decline was found in the T level of prostates in the 40 g/kg and 80 mg/kg AST-treated rats and the DHT level of prostates in the 40 mg/kg AST-treated rats. These results indicate that AST might have an inhibitory effect on T-induced BPH in rats, possibly due to SOD activity regulation and T and DHT levels.
Deep-Sea Anemones Are Prospective Source of New Antimicrobial and Cytotoxic Compounds
Authors: Kvetkina Aleksandra , Kostina Elena , Gladkikh Irina , Chausova Victoria , Yurchenko Ekaterina , Bakunina Irina , Pivkin Mikhail , Anastyuk Stanislav , Popov Roman , Monastyrnaya Margarita , Kozlovskaya Emma , Isaeva Marina , Dmitrenok Pavel , Leychenko Elena
Published: December 2021

The peculiarities of the survival and adaptation of deep-sea organisms raise interest in the study of their metabolites as promising drugs. In this work, the hemolytic, cytotoxic, antimicrobial, and enzyme-inhibitory activities of tentacle extracts from five species of sea anemones (Cnidaria, orders Actiniaria and Corallimorpharia) collected near the Kuril and Commander Islands of the Far East of Russia were evaluated for the first time. The extracts of Liponema brevicorne and Actinostola callosa demonstrated maximal hemolytic activity, while high cytotoxic activity against murine splenocytes and Ehrlich carcinoma cells was found in the extract of Actinostola faeculenta. The extracts of Corallimorphus cf. pilatus demonstrated the greatest activity against Ehrlich carcinoma cells but were not toxic to mouse spleen cells. Sea anemones C. cf. pilatus and Stomphia coccinea are promising sources of antimicrobial and antifungal compounds, being active against Gram-positive bacteria Bacillus subtilis, Staphylococcus aureus, and yeast Candida albicans. Moreover, all sea anemones contain α-galactosidase inhibitors. Peptide mass fingerprinting of L. brevicorne and C. cf. pilatus extracts provided a wide range of peptides, predominantly with molecular masses of 4000–5900 Da, which may belong to a known or new structural class of toxins. The obtained data allow concluding that deep-sea anemones are a promising source of compounds for drug discovery.
Microalgal Peloids for Cosmetic and Wellness Uses
Authors: Mourelle M. Lourdes , Gómez Carmen P. , Legido José L.
Published: December 2021

Peloids have been used for therapeutic purposes since time immemorial, mainly in the treatment of locomotor system pathologies and dermatology. Their effects are attributed to their components, i.e., to the properties and action of mineral waters, clays, and their biological fraction, which may be made up of microalgae, cyanobacteria, and other organisms present in water and clays. There are many studies on the therapeutic use of peloids made with microalgae/cyanobacteria, but very little research has been done on dermocosmetic applications. Such research demonstrates their potential as soothing, regenerating, antioxidant, anti-inflammatory, and antimicrobial agents. In this work, a method for the manufacture of a dermocosmetic peloid is presented based on the experience of the authors and existing publications, with indications for its characterization and study of its efficacy.
On the Path to Thermo-Stable Collagen: Culturing the Versatile Sponge Chondrosia reniformis
Authors: Orel Boaz , Giovine Marco , Ilan Micha
Published: December 2021

The collagen proteins family is sought-after in the pharmaceuticals, cosmetics, and food industries for various biotechnological applications. The most abundant sources of collagen are pigs and cows, but due to religious restrictions and possible disease transmission, they became less attractive. An alternative source can be found in marine invertebrates, specifically in sponges. Alas, two problems arise: (1). Growing sponges is complicated. (2). Sponge collagen has low heat tolerance, which can impose a problem for human biotechnological usage. To fill these gaps, we studied the collagen-abundant sponge Chondrosia reniformis. Two culture experiments were conducted: (1). A sea-based system examined the difference in growth rates of C. reniformis from different habitats, growing under natural seasonal conditions; (2). A land-based controlled system, which assessed the growth-rate of C. reniformis at different temperatures. The results reveal that C. reniformis from shallow habitats are growing larger and faster than individuals from colder, deeper habitats, and that the optimal temperature for C. reniformis growth is 25 °C. The results demonstrate that C. reniformis is highly fit for culture and can produce thermally stable collagen. Further research is needed to determine the best conditions for C. reniformis culture for collagen extract and other exciting materials for bioprospecting.
Gracilaria gracilis (Gracilariales, Rhodophyta) from Dakhla (Southern Moroccan Atlantic Coast) as Source of Agar: Content, Chemical Characteristics, and Gelling Properties
Authors: Belattmania Zahira , Bhaby Sanaa , Nadri Amal , Khaya Khaoulaa , Bentiss Fouad , Jama Charafeddine , Reani Abdeltif , Vasconcelos Vitor , Sabour Brahim
Published: December 2021

Agar is a sulfated polysaccharide extracted from certain marine red algae, and its gel properties depend on the seaweed source and extraction conditions. In the present study, the seaweed Gracilaria gracilis (Gracilariales, Rhodophyta) from Dakhla (Moroccan Atlantic Coast) was investigated for its agar content, structure, and gel properties. The agar yields of G. gracilis were 20.5% and 15.6% from alkaline pretreatment and native extraction, respectively. Agar with alkaline pretreatment showed a better gelling property supported by higher gel strength (377 g·cm−2), gelling (35.4 °C), and melting (82.1 °C) temperatures with a notable increase in 3,6-anhydro-galactose (11.85%) and decrease in sulphate (0.32%) contents. The sulfate falling subsequent to alkaline pretreatment was verified through FT-IR spectroscopy. The 13C NMR spectroscopy showed that alkaline-pretreated agar has a typical unsubstituted agar pattern. However, native agar had a partially methylated agarose structure. Overall, this study suggested the possibility of the exploitation of G. gracilis to produce a fine-quality agar. Yet, further investigation may need to determine the seasonal variability of this biopolymer according to the life cycle of G. gracilis.
Anti-Inflammatory Mechanisms of Fucoidans to Treat Inflammatory Diseases: A Review
Authors: Sanjeewa Kalu K. Asanka , Herath Kalahe H. I. N. M. , Yang Hye-Won , Choi Cheol Soo , Jeon You-Jin
Published: December 2021

Fucoidans are sulfated heteropolysaccharides found in the cell walls of brown seaweeds (Phaeophyceae) and in some marine invertebrates. Generally, fucoidans are composed of significant amounts of L-fucose and sulfate groups, and lesser amounts of arabinose, galactose, glucose, glucuronic acid, mannose, rhamnose, and xylose. In recent years, fucoidans isolated from brown seaweeds have gained considerable attention owing to their promising bioactive properties such as antioxidant, immunomodulatory, anti-inflammatory, antiobesity, antidiabetic, and anticancer properties. Inflammation is a complex immune response that protects the organs from infection and tissue injury. While controlled inflammatory responses are beneficial to the host, leading to the removal of immunostimulants from the host tissues and restoration of structural and physiological functions in the host tissues, chronic inflammatory responses are often associated with the pathogenesis of tumor development, arthritis, cardiovascular diseases, diabetes, obesity, and neurodegenerative diseases. In this review, the authors mainly discuss the studies since 2016 that have reported anti-inflammatory properties of fucoidans isolated from various brown seaweeds, and their potential as a novel functional material for the treatment of inflammatory diseases.
Expanding the Repertoire of Spongian-16-One Derivatives in Australian Nudibranchs of the Genus Goniobranchus and Evaluation of Their Anatomical Distribution
Authors: Forster Louise C. , Clegg Jack K. , Cheney Karen L. , Garson Mary J.
Published: December 2021

Extracts of the mantle and viscera of the Indo-Pacific nudibranchs Goniobranchus aureopurpureus and Goniobranchus sp. 1 afforded 11 new diterpenoids (1–11), all of which possess a tetracyclic spongian-16-one scaffold with extensive oxidation at C-6, C-7, C-11, C-12, C-13, and/or C-20. The structures and relative configuration were investigated by NMR experiments, while X-ray crystallography provided the absolute configuration of 1, including a 2′S configuration for the 2-methylbutanoate substituent located at C-7. Dissection of animal tissue revealed that the mantle and viscera tissues differed in their metabolite composition with diterpenes 1–11 present in the mantle tissue of the two nudibranch species.
Natural Benzo/Acetophenones as Leads for New Synthetic Acetophenone Hybrids Containing a 1,2,3-Triazole Ring as Potential Antifouling Agents
Authors: Neves Ana Rita , Pereira Daniela , Gonçalves Catarina , Cardoso Joana , Pinto Eugénia , Vasconcelos Vitor , Pinto Madalena , Sousa Emília , Almeida Joana R. , Cidade Honorina , Correia-da-Silva Marta
Published: December 2021

Marine biofouling is a natural process that represents major economic, environmental, and health concerns. Some booster biocides have been used in biofouling control, however, they were found to accumulate in environmental compartments, showing negative effects on marine organisms. Therefore, it is urgent to develop new eco-friendly alternatives. Phenyl ketones, such as benzophenones and acetophenones, have been described as modulators of several biological activities, including antifouling activity (AF). In this work, acetophenones were combined with other chemical substrates through a 1,2,3-triazole ring, a strategy commonly used in Medicinal Chemistry. In our approach, a library of 14 new acetophenone–triazole hybrids was obtained through the copper(I)-catalyzed alkyne-azide cycloaddition “click” reaction. All of the synthesized compounds were evaluated against the settlement of a representative macrofouling species, Mytilus galloprovincialis, as well as on biofilm-forming marine microorganisms, including bacteria and fungi. The growth of the microalgae Navicula sp. was also evaluated after exposure to the most promising compounds. While compounds 6a, 7a, and 9a caused significant inhibition of the settlement of mussel larvae, compounds 3b, 4b, and 7b were able to inhibit Roseobacter litoralis bacterial biofilm growth. Interestingly, acetophenone 7a displayed activity against both mussel larvae and the microalgae Navicula sp., suggesting a complementary action of this compound against macro- and microfouling species. The most potent compounds (6a, 7a, and 9a) also showed to be less toxic to the non-target species Artemia salina than the biocide Econea®. Regarding both AF potency and ecotoxicity activity evaluation, acetophenones 7a and 9a were put forward in this work as promising eco-friendly AF agents.
Small Bowel Metastatic Melanoma: An Emblematic “Coal-Black” Appearance at Videocapsule Endoscopy
Authors: Todeschini Alessia , Loconte Ilaria , Contaldo Antonella , Ierardi Enzo , Di Leo Alfredo , Principi Mariabeatrice
Published: December 2021

A 80-year-old woman underwent vulvar melanoma resection and segmental lung resection for pulmonary metastasis. Immunotherapy with Nivolumab was performed. One year later, the patient was admitted for gastrointestinal (GI) recurrent bleeding and severe anemia. Esophagoastroduodenoscopy and colonoscopy did not show any abnormality, while videocapsule endoscopy (VCE) revealed an irregular and exophytic whitish area with a “coal-black” central depression. Small bowel resection was performed and histological examination revealed S100 protein strongly positive melanoma metastasis. The patient died six months later from disease progression. A “coal-black” appearance of intestinal metastatic melanoma has been described only twice before this report. In one case the patient had been treated by immunotherapy with interferon A and dendritic cell-based vaccination. In our patient, it is presumable that the picture we observed was a consequence of Nivolumab treatment inducing the disappearance of melanocytes in the area surrounding the metastasis with the onset of the central coal-black lesion encircled by whitish tissue. This picture should be emblematic of intestinal metastatic melanoma in subjects treated with immunotherapy showing occult/obscure bleeding.
Determining Response to Treatment for Drug-Induced Bronchocentric Granulomatosis by the Forced Oscillation Technique
Authors: Fukahori Susumu , Obase Yasushi , Fukushima Chizu , Takao Daisuke , Iriki Jun , Ozasa Mutsumi , Zaizen Yoshiaki , Takamura Noboru , Fukuoka Junya , Ashizawa Kazuto , Mukae Hiroshi
Published: December 2021

Anti-tumor necrosis factor alpha (TNFα) therapy is widely used to treat various inflammatory conditions. Paradoxically, there are several case reports describing the development of bronchocentric granulomatosis treated with TNFα inhibitors, and it is difficult to determine the effect of treatment using conventional spirometry because the lesions are located in small airways. However, it has been reported that the forced oscillation technique (FOT) is useful in the evaluation of small airway disease in bronchial asthma or chronic obstructive pulmonary disease. We performed the FOT to determine the effect of treatment on bronchocentric granulomatosis and found it to be useful. We report the case of a 55-year-old female with ulcerative colitis who was treated with golimumab and who developed bronchocentric granulomatosis as a sarcoid-like reaction to golimumab. She was successfully treated with prednisone, and the treatment efficacy was confirmed by the FOT. The FOT may be useful in the evaluation of small airway disease in bronchocentric granulomatosis. This case may help inform clinicians of the usefulness of the FOT to assess small airway disease in various diseases.
Incidence of Malocclusion among Young Patients with Gingival Recessions—A Cross-Sectional Observational Pilot Study
Authors: Tomina Darius , Buduru Smaranda , Dinu Cristian Mihail , Kui Andreea , Dee Cătălina , Cosgarea Raluca , Negucioiu Marius
Published: December 2021

Background and Objectives: Dental occlusion and gingival recession have been studied over the past years especially because of the increasing incidence of occlusal interferences in young patients. The purpose of this pilot study is to investigate any association between occlusal dysfunctions and gingival recessions. Data on gingival phenotype and previous orthodontic treatment were also collected to assess any correlation with the presence of gingival recession. Materials and Methods: Forty systemically healthy subjects, without signs of periodontitis and with gingival recessions, were included in the study. The following parameters were determined: location and extent of the gingival recession, gingival phenotype and functional occlusion by means of observing and registering the occlusal contacts in maximum intercuspation position, protrusive and lateral guidance. Results: Premolars were mostly affected in cases of working-side interferences during lateral guidance (71.19% of the affected teeth during left and 75% during right mandibular movements). The chi-squared exact test applied for the analysis of contingency tables revealed statistically significant associations between excursive interferences during lateral guidance and anterior guidance and the presence of gingival recession on the involved group of teeth. Conclusions: The results suggest that most gingival recessions might be associated with working-side interferences, the highest number of gingival recessions being associated with active interferences during lateral guidance.
Career Networks in Shock: An Agenda for in-COVID/Post-COVID Career-Related Social Capital
Authors: Froehlich Dominik Emanuel
Published: December 2021

The COVID-19 pandemic was a career shock for many, including early and mid-career researchers. Due to the (digital) transformation it has caused in the social domain, it may have lastingly changed the rules for career development. In this conceptual paper, we investigate how the changed social environment created gaps in our understanding of academic career development and the role social capital plays in it. Our narrative review of the literature arrives at three major gaps: two are related to the nature, antecedents, and outcomes of (career-related) social capital, and one is related to the methodological backdrop of how knowledge is being generated in this domain. Based on the identified gaps, we specify avenues for further (and much needed) research.
Methodology to Create Reproducible Validation/Reference Materials for Comparison of Filter-Based Measurements of Carbonaceous Aerosols That Measure BC, BrC, EC, OC, and TC
Authors: Solomon Paul A. , Hyatt Anna-Marie , Hansen Anthony D. A. , Schauer James J. , Hyslop Nicole P. , Watson John G. , Doraiswamy Prakash , Presler-Jur Paige
Published: December 2021

A simple method that reproducibly creates validation/reference materials for comparison of methods that measure the carbonaceous content of atmospheric particulate matter deposited on filter media at concentrations relevant to atmospheric levels has been developed and evaluated. Commonly used methods to determine the major carbonaceous components of particles collected on filters include optical attenuation for “Black” (BC) and “Brown” (BrC) carbon, thermal-optical analysis (TOA) for “Elemental” (EC) and “Organic” (OC) carbon, and total combustion for “Total” carbon (TC). The new method uses a commercial inkjet printer to deposit ink containing both organic and inorganic components onto filter substrates at programmable print densities (print levels, as specified by the printer–software combination). A variety of filter media were evaluated. The optical attenuation (ATN) of the deposited sample was determined at 880 nm and 370 nm. Reproducibility or precision (as standard deviation or in percent as coefficient of variation) in ATN for Teflon-coated glass-fiber, Teflon, and cellulose substrates was better than 5%. Reproducibility for other substrates was better than 15%. EC and OC measured on quartz-fiber filters (QFF) compared to ATN measured at 880 nm and 370 nm on either QFF or Teflon-coated glass-fiber yielded R2 > 0.92 and >0.97, respectively. Four independent laboratories participated in a round robin study together with the reference laboratory. The propagated standard deviation among the five groups across all print levels was <2.2 ATN at 880 nm and <2.7 ATN at 370 nm with a coefficient of variation of <2% at ~100 ATN.
A Lagrangian Tool for Simulating the Transport of Chemical Pollutants in the Arabian/Persian Gulf
Authors: Periáñez Raúl
Published: December 2021

A rapid-response Lagrangian model for the use in simulation of the transport of a chemical pollutant in the Arabian/Persian Gulf is described. The model is well suited to the provision of a fast response after an emergency due to an accident or a deliberate spill. It is easy to set up for any situation since only requires the modification of a few input files specifying the pollutant properties and release characteristics. Running times are short, even on a desktop PC, which makes it appropriate for a rapid assessment of a hypothetical accident occurring in the region. Baroclinic circulation was obtained from an HYCOM ocean model, and tides were calculated using a barotropic model. The interactions of pollutants with sediments (uptake/release processes) were described using a dynamic approach based on kinetic transfer coefficients and a stochastic numerical method. Some examples of model applications are shown, showing the influence of the geochemical behaviour of the pollutant in its distribution patterns.
Ferrocene-Labelled Electroactive Aptamer-Based Sensors (Aptasensors) for Glycated Haemoglobin
Authors: Feng Xue-Qing , Ju Yi , Dou Wei-Tao , Li Qing , Jin Zhong-Gan , He Xiao-Peng , James Tony D. , Ye Bang-Ce
Published: December 2021

Glycated haemoglobin (HbA1c) is a diagnostic biomarker for type 2 diabetes. Traditional analytical methods for haemoglobin (Hb) detection rely on chromatography, which requires significant instrumentation and is labour-intensive; consequently, miniaturized devices that can rapidly sense HbA1c are urgently required. With this research, we report on an aptamer-based sensor (aptasensor) for the rapid and selective electrochemical detection of HbA1c. Aptamers that specifically bind HbA1c and Hb were modified with a sulfhydryl and ferrocene group at the 3′ and 5′-end, respectively. The modified aptamers were coated through sulfhydryl-gold self-assembly onto screen printed electrodes, producing aptasensors with built in electroactivity. When haemoglobin was added to the electrodes, the current intensity of the ferrocene in the sensor system was reduced in a concentration-dependent manner as determined by differential pulse voltammetry. In addition, electrochemical impedance spectroscopy confirmed selective binding of the analytes to the aptamer-coated electrode. This research offers new insight into the development of portable electrochemical sensors for the detection of HbA1c
An Outline of the Latest Crystallographic Studies on Inhibitor-Enzyme Complexes for the Design and Development of New Therapeutics against Tuberculosis
Authors: Mori Matteo , Villa Stefania , Ciceri Samuele , Colombo Diego , Ferraboschi Patrizia , Meneghetti Fiorella
Published: December 2021

The elucidation of the structure of enzymes and their complexes with ligands continues to provide invaluable insights for the development of drugs against many diseases, including bacterial infections. After nearly three decades since the World Health Organization’s (WHO) declaration of tuberculosis (TB) as a global health emergency, Mycobacterium tuberculosis (Mtb) continues to claim millions of lives, remaining among the leading causes of death worldwide. In the last years, several efforts have been devoted to shortening and improving treatment outcomes, and to overcoming the increasing resistance phenomenon. The structural elucidation of enzyme-ligand complexes is fundamental to identify hot-spots, define possible interaction sites, and elaborate strategies to develop optimized molecules with high affinity. This review offers a critical and comprehensive overview of the most recent structural information on traditional and emerging mycobacterial enzymatic targets. A selection of more than twenty enzymes is here discussed, with a special emphasis on the analysis of their binding sites, the definition of the structure–activity relationships (SARs) of their inhibitors, and the study of their main intermolecular interactions. This work corroborates the potential of structural studies, substantiating their relevance in future anti-mycobacterial drug discovery and development efforts.
Origanum vulgare ssp. hirtum (Lamiaceae) Essential Oil Prevents Behavioral and Oxidative Stress Changes in the Scopolamine Zebrafish Model
Authors: Capatina Luminita , Napoli Edoardo Marco , Ruberto Giuseppe , Hritcu Lucian
Published: December 2021

Origanum vulgare ssp. hirtum has been used as medicinal herbs promoting antioxidant, anti-inflammatory, antimicrobial, and neuroprotective activities. We investigated the protective effects and the mechanism of O. vulgare ssp. hirtum essential oil (OEO) on cognitive impairment and brain oxidative stress in a scopolamine (Sco)-induced zebrafish (Danio rerio) model of cognitive impairment. Our results show that exposure to Sco (100 µM) leads to anxiety, spatial memory, and response to novelty dysfunctions, whereas the administration of OEO (25, 150, and 300 µL/L, once daily for 13 days) reduced anxiety-like behavior and improved cognitive ability, which was confirmed by behavioral tests, such as the novel tank-diving test (NTT), Y-maze test, and novel object recognition test (NOR) in zebrafish. Additionally, Sco-induced brain oxidative stress and increasing of acetylcholinesterase (AChE) activity were attenuated by the administration of OEO. The gas chromatography–mass spectrometry (GC-MS) analyses were used to elucidate the OEO composition, comprising thymol (38.82%), p-cymene (20.28%), and γ-terpinene (19.58%) as the main identified components. These findings suggest the ability of OEO to revert the Sco-induced cognitive deficits by restoring the cholinergic system activity and brain antioxidant status. Thus, OEO could be used as perspective sources of bioactive compounds, displaying valuable biological activities, with potential pharmaceutical applications.
Ginsenoside Rb1 Mitigates Escherichia coli Lipopolysaccharide-Induced Endometritis through TLR4-Mediated NF-κB Pathway
Authors: Shaukat Aftab , Shaukat Irfan , Rajput Shahid Ali , Shukat Rizwan , Hanif Sana , Shaukat Imran , Zhang Xinxin , Chen Chao , Sun Xuyang , Ye Tingzhu , Niu Kaifeng , Yao Zhiqiu , Shaukat Shadab , Safdar Muhammad , Abdelrahman Mohamed , Riaz Umair , Zhao Junwei , Gu Xiaoying , Yang Liguo
Published: December 2021

Endometritis is the inflammatory response of the endometrial lining of the uterus and is associated with low conception rates, early embryonic mortality, and prolonged inter-calving intervals, and thus poses huge economic losses to the dairy industry worldwide. Ginsenoside Rb1 (GnRb1) is a natural compound obtained from the roots of Panax ginseng, having several pharmacological and biological properties. However, the anti-inflammatory properties of GnRb1 in lipopolysaccharide (LPS)-challenged endometritis through the TLR4-mediated NF-κB signaling pathway has not yet been researched. This study was planned to evaluate the mechanisms of how GnRb1 rescues LPS-induced endometritis. In the present research, histopathological findings revealed that GnRb1 ameliorated LPS-triggered uterine injury. The ELISA and RT-qPCR assay findings indicated that GnRb1 suppressed the expression level of pro-inflammatory molecules (TNF-α, IL-1β and IL-6) and boosted the level of anti-inflammatory (IL-10) cytokine. Furthermore, the molecular study suggested that GnRb1 attenuated TLR4-mediated NF-κB signaling. The results demonstrated the therapeutic efficacy of GnRb1 in the mouse model of LPS-triggered endometritis via the inhibition of the TLR4-associated NF-κB pathway. Taken together, this study provides a baseline for the protective effect of GnRb1 to treat endometritis in both humans and animals.
Two New Triterpenes from Basidiomata of the Medicinal and Edible Mushroom, Laetiporus sulphureus
Authors: Hassan Khadija , Matio Kemkuignou Blondelle , Stadler Marc
Published: December 2021

In the search for novel anti-infectives from natural sources, fungi, in particular basidiomycetes, have proven to still harbor so much potential in terms of secondary metabolites diversity. There have been numerous reports on isolating numerous secondary metabolites from genus Laetiporus. This study reports on two new triterpenoids, laetiporins C and D, and four known triterpenes from the fruiting body of L. sulphureus. The structures of the isolated compounds were elucidated based on their 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data in combination with high-resolution electrospray mass spectrometric (HR-ESIMS) data. Laetiporin C exhibited weak antifungal activity against Mucor hiemalis. Furthermore, the compounds showed weak antiproliferative activity against the mouse fibroblast L929 and human cancer cell lines, including KB-3-1, A431, MCF-7, PC-3 and A549.
Identification of Novel Antistaphylococcal Hit Compounds Targeting Sortase A
Authors: Volynets Galyna , Vyshniakova Hanna , Nitulescu Georgiana , Nitulescu George Mihai , Ungurianu Anca , Margina Denisa , Moshynets Olena , Bdzhola Volodymyr , Koleiev Ihor , Iungin Olga , Tarnavskiy Sergiy , Yarmoluk Sergiy
Published: December 2021

Staphylococcus aureus (S. aureus) is a causative agent of many hospital- and community-acquired infections with the tendency to develop resistance to all known antibiotics. Therefore, the development of novel antistaphylococcal agents is of urgent need. Sortase A is considered a promising molecular target for the development of antistaphylococcal agents. The main aim of this study was to identify novel sortase A inhibitors. In order to find novel antistaphylococcal agents, we performed phenotypic screening of a library containing 15512 compounds against S. aureus ATCC43300. The molecular docking of hits was performed using the DOCK program and 10 compounds were selected for in vitro enzymatic activity inhibition assay. Two inhibitors were identified, N,N-diethyl-N′-(5-nitro-2-(quinazolin-2-yl)phenyl)propane-1,3-diamine (1) and acridin-9-yl-(1H-benzoimidazol-5-yl)-amine (2), which decrease sortase A activity with IC50 values of 160.3 µM and 207.01 µM, respectively. It was found that compounds 1 and 2 possess antibacterial activity toward 29 tested multidrug resistant S. aureus strains with MIC values ranging from 78.12 to 312.5 mg/L. These compounds can be used for further structural optimization and biological research.
Detecting Air Pollutant Molecules Using Tube-Shaped Single Electron Transistor
Authors: Huang Zhongkai , Peng Xiangyang , Peng Cheng , Huang Jin , Bo Maolin , Yao Chuang , Li Jibiao
Published: December 2021

An air pollution detector is proposed based on a tube-shaped single-electron transistor (SET) sensor. By monitoring the flow control component of the detector, each air pollutant molecule can be placed at the center of a SET nanopore and is treated as an island of the SET device in the same framework. Electron transport in the SET was incoherent, and the performances of the SET were sensitive at the single molecule level. Employing first-principles calculations, electronic features of an air pollutant molecule within a tube-shaped SET environment were found to be independent of the molecule rotational orientations with respect to axis of symmetry, unlike the electronic features in a conventional SET environment. Charge stability diagrams of the island molecules were demonstrated to be distinct for each molecule, and thus they can serve as electronic fingerprints for detection. Using the same setup, quantification of the air pollutant can be realized at room temperature as well. The results presented herein may help provide guidance for the identification and quantification of various types of air pollutants at the molecular level by treating the molecule as the island of the SET component in the proposed detector.