bluuebunny/crossref_metadata_2025 huggingface dataset:
Unique Mitochondrial Single Nucleotide Polymorphisms Demonstrate Resolution Potential to Discriminate Theileria parva Vaccine and Buffalo-Derived Strains
Authors: Mwamuye Micky M. , Obara Isaiah , Elati Khawla , Odongo David , Bakheit Mohammed A. , Jongejan Frans , Nijhof Ard M.
Published: December 2020

Distinct pathogenic and epidemiological features underlie different Theileria parva strains resulting in different clinical manifestations of East Coast Fever and Corridor Disease in susceptible cattle. Unclear delineation of these strains limits the control of these diseases in endemic areas. Hence, an accurate characterization of strains can improve the treatment and prevention approaches as well as investigate their origin. Here, we describe a set of single nucleotide polymorphisms (SNPs) based on 13 near-complete mitogenomes of T. parva strains originating from East and Southern Africa, including the live vaccine stock strains. We identified 11 SNPs that are non-preferentially distributed within the coding and non-coding regions, all of which are synonymous except for two within the cytochrome b gene of buffalo-derived strains. Our analysis ascertains haplotype-specific mutations that segregate the different vaccine and the buffalo-derived strains except T. parva-Muguga and Serengeti-transformed strains suggesting a shared lineage between the latter two vaccine strains. Phylogenetic analyses including the mitogenomes of other Theileria species: T. annulata, T. taurotragi, and T. lestoquardi, with the latter two sequenced in this study for the first time, were congruent with nuclear-encoded genes. Importantly, we describe seven T. parva haplotypes characterized by synonymous SNPs and parsimony-informative characters with the other three transforming species mitogenomes. We anticipate that tracking T. parva mitochondrial haplotypes from this study will provide insight into the parasite’s epidemiological dynamics and underpin current control efforts.
Twinning–Detwinning in Pre-Compressed and Thermally Treated ZX10 and ZN10 Alloys
Authors: Drozdenko Daria , Dobroň Patrik , Fekete Klaudia , Yi Sangbong , Bohlen Jan
Published: December 2020

The deformation behavior of extruded Mg alloys with a Ca or Nd addition (up to 0.5 wt.%) is addressed with respect to a specified thermo-mechanical treatment, realized by pre-compression and subsequent heat treatment at intermediate temperature. The twinning–detwinning process is discussed with respect to the initial texture and applied heat treatment. Isothermal aging leads to precipitation and segregation along twin boundaries and dislocations in the pre-compressed Mg alloys, and, thus, variation in the mobility of twin boundaries (TB) is observed in the investigated alloys. Despite individual scenarios of TB mobility in particular grains, in general, the same TB mobility modes are observed in the alloys independently on Ca or Nd alloying. The microstructure development, particularly the twin volume fraction and the mobility of tensile {10-12} twin boundaries, is tracked using scanning electron microscopy, including backscattered electron (BSE) imaging and electron backscatter diffraction (EBSD) mapping.
Microstructural, Mechanical, Corrosion and Cytotoxicity Characterization of Porous Ti-Si Alloys with Pore-Forming Agent
Authors: Školáková Andrea , Körberová Jana , Málek Jaroslav , Rohanová Dana , Jablonská Eva , Pinc Jan , Salvetr Pavel , Gregorová Eva , Novák Pavel
Published: December 2020

Titanium and its alloys belong to the group of materials used in implantology due to their biocompatibility, outstanding corrosion resistance and good mechanical properties. However, the value of Young’s modulus is too high in comparison with the human bone, which could result in the failure of implants. This problem can be overcome by creating pores in the materials, which, moreover, improves the osseointegration. Therefore, TiSi2 and TiSi2 with 20 wt.% of the pore-forming agent (PA) were prepared by reactive sintering and compared with pure titanium and titanium with the addition of various PA content in this study. For manufacturing implants (especially augmentation or spinal replacements), titanium with PA seemed to be more suitable than TiSi2 + 20 wt.% PA. In addition, titanium with 30 or 40 wt.% PA contained pores with a size allowing bone tissue ingrowth. Furthermore, Ti + 30 wt.% PA was more suitable material in terms of corrosion resistance; however, its Young’s modulus was higher than that of the human bone while Ti + 40 wt.% PA had a Young’s modulus close to the human bone.
3-D Cell Culture Systems in Bone Marrow Tissue and Organoid Engineering, and BM Phantoms as In Vitro Models of Hematological Cancer Therapeutics—A Review
Authors: Janagama Dasharatham , Hui Susanta K.
Published: December 2020

We review the state-of-the-art in bone and marrow tissue engineering (BMTE) and hematological cancer tissue engineering (HCTE) in light of the recent interest in bone marrow environment and pathophysiology of hematological cancers. This review focuses on engineered BM tissue and organoids as in vitro models of hematological cancer therapeutics, along with identification of BM components and their integration as synthetically engineered BM mimetic scaffolds. In addition, the review details interaction dynamics of various BM and hematologic cancer (HC) cell types in co-culture systems of engineered BM tissues/phantoms as well as their relation to drug resistance and cytotoxicity. Interaction between hematological cancer cells and their niche, and the difference with respect to the healthy niche microenvironment narrated. Future perspectives of BMTE for in vitro disease models, BM regeneration and large scale ex vivo expansion of hematopoietic and mesenchymal stem cells for transplantation and therapy are explained. We conclude by overviewing the clinical application of biomaterials in BM and HC pathophysiology and its challenges and opportunities.
Coupled Free Vibration of Spinning Functionally Graded Porous Double-Bladed Disk Systems Reinforced with Graphene Nanoplatelets
Authors: Zhao Tianyu , Ma Yu , Zhang Hongyuan , Yang Jie
Published: December 2020

This paper presents, for the first time, the mechanical model and theoretical analysis of free vibration of a spinning functionally graded graphene nanoplatelets reinforced composite (FG-GPLRC) porous double-bladed disk system. The nanocomposite rotor is made of porous metal matrix and graphene nanoplatelet (GPL) reinforcement material with different porosity and nanofillers distributions. The effective material properties of the system are graded in a layer-wise manner along the thickness directions of the blade and disk. Considering the gyroscopic effect, the coupled model of the double-bladed disk system is established based on Euler–Bernoulli beam theory for the blade and Kirchhoff’s plate theory for the disk. The governing equations of motion are derived by employing the Lagrange’s equation and then solved by employing the substructure mode synthesis method and the assumed modes method. A comprehensive parametric analysis is conducted to examine the effects of the distribution pattern, weight fraction, length-to-thickness ratio, and length-to-width ratio of graphene nanoplatelets, porosity distribution pattern, porosity coefficient, spinning speed, blade length, and disk inner radius on the free vibration characteristics of the FG-GPLRC double-bladed disk system.
Resistive Switching in Electrodeposited Prussian Blue Layers
Authors: Avila Lindiomar Borges , Müller Christian K. , Hildebrand Dirk , Faita Fabrício L. , Baggio Bruna F. , Cid Cristiani C. Plá , Pasa André A.
Published: December 2020

Prussian blue (PB) layers were electrodeposited for the fabrication of Au/PB/Ag stacks to study the resistive switching effect. The PB layers were characterized by different techniques to prove the homogeneity, composition, and structure. Electrical measurements confirmed the bipolar switching behavior with at least 3 orders of magnitude in current and the effect persisting for the 200 cycles tested. The low resistance state follows the ohmic conduction with an activation energy of 0.2 eV.
Inter-Stage Dynamic Performance of an Axial Compressor of a Twin-Shaft Industrial Gas Turbine
Authors: Cruz-Manzo Samuel , Krishnababu Senthil , Panov Vili , Bingham Chris
Published: December 2020

In this study, the inter-stage dynamic performance of a multistage axial compressor is simulated through a semi-empirical model constructed in the Matlab Simulink environment. A semi-empirical 1-D compressor model developed in a previous study has been integrated with a 0-D twin-shaft gas turbine model developed in the Simulink environment. Inter-stage performance data generated through a high-fidelity design tool and based on throughflow analysis are considered for the development of the inter-stage modeling framework. Inter-stage performance data comprise pressure ratio at various speeds with nominal variable stator guide vane (VGV) positions and with hypothetical offsets to them with respect to the gas generator speed (GGS). Compressor discharge pressure, fuel flow demand, GGS and power turbine speed measured during the operation of a twin-shaft industrial gas turbine are considered for the dynamic model validation. The dynamic performance of the axial-compressor, simulated by the developed modeling framework, is represented on the overall compressor map and individual stage characteristic maps. The effect of extracting air through the bleed port in the engine center-casing on transient performance represented on overall compressor map and stage performance maps is also presented. In addition, the dynamic performance of the axial-compressor with an offset in VGV position is represented on the overall compressor map and individual stage characteristic maps. The study couples the fundamental principles of axial compressors and a semi-empirical modeling architecture in a complementary manner. The developed modeling framework can provide a deeper understanding of the factors that affect the dynamic performance of axial compressors.
Radio Number Associated with Zero Divisor Graph
Authors: Koam Ali N. A. , Ahmad Ali , Haider Azeem
Published: December 2020

Radio antennas use different frequency bands of Electromagnetic (EM) Spectrum for switching signals in the forms of radio waves. Regulatory authorities issue a unique number (unique identifying call sign) to each radio center, that must be used in all transmissions. Each radio center propagates channels to the two nearer radio centers so they must use distinctive numbers to avoid interruption. The task of effectively apportioning channels to transmitters is known as the Channel Assignment (CA) problem. CA Problem is discussed under the topic of graph coloring by mathematicians. The radio number of a graph can be used in many parts of the field communication. In this paper, we determined the radio number of zero-divisor graphs Γ(Zp2×Zq2) for p,q prime numbers.
Partial Key Attack Given MSBs of CRT-RSA Private Keys
Authors: Abd Ghafar Amir Hamzah Abd , Kamel Ariffin Muhammad Rezal Kamel , Md Yasin Sharifah Md , Sapar Siti Hasana
Published: December 2020

The CRT-RSA cryptosystem is the most widely adopted RSA variant in digital applications. It exploits the properties of the Chinese remainder theorem (CRT) to elegantly reduce the size of the private keys. This significantly increases the efficiency of the RSA decryption algorithm. Nevertheless, an attack on RSA may also be applied to this RSA variant. One of the attacks is called partially known private key attack, that relies on the assumption that the adversary has knowledge of partial bits regarding RSA private keys. In this paper, we mount this type of attack on CRT-RSA. By using partial most significant bits (MSBs) of one of the RSA primes, p or q and its corresponding private exponent, d, we obtain an RSA intermediate. The intermediate is derived from p−1 and RSA public key, e. The analytical and novel reason on the success of our attack is that once the adversary has obtained the parameters: approximation of private exponent d˜p, approximation of p, p˜ and the public exponent e where d˜p,p˜,e=Nα/2 where 0<α≤1/4 such that |dp−d˜p|,|p−p˜|<N1−α2 and has determined the largest prime of p−1e, it will enable the adversary to factor the RSA modulus N=pq. Although the parameter space to find the prime factor is large, we show that one can adjust its “success appetite” by applying prime-counting function properties. By comparing our method with contemporary partial key attacks on CRT-RSA, upon determining a suitable predetermined “success appetite” value, we found out that our method required fewer bits of the private keys in order to factor N.
Statistical Approach for the Design of Structural Self-Compacting Concrete with Fine Recycled Concrete Aggregate
Authors: Revilla-Cuesta Víctor , Skaf Marta , Espinosa Ana B. , Santamaría Amaia , Ortega-López Vanesa
Published: December 2020

The compressive strength of recycled concrete is acknowledged to be largely conditioned by the incorporation ratio of Recycled Concrete Aggregate (RCA), although that ratio needs to be carefully assessed to optimize the design of structural applications. In this study, Self-Compacting Concrete (SCC) mixes containing 100% coarse RCA and variable amounts, between 0% and 100%, of fine RCA were manufactured and their compressive strengths were tested in the laboratory for a statistical analysis of their strength variations, which exhibited robustness and normality according to the common statistical procedures. The results of the confidence intervals, the one-factor ANalysis Of VAriance (ANOVA), and the Kruskal–Wallis test showed that an increase in fine RCA content did not necessarily result in a significant decrease in strength, although the addition of fine RCA delayed the development of the final strength. The statistical models presented in this research can be used to define the optimum incorporation ratio that would produce the highest compressive strength. Furthermore, the multiple regression models offered accurate estimations of compressive strength, considering the interaction between the incorporation ratio of fine RCA and the curing age of concrete that the two-factor ANOVA revealed. Lastly, the probability distribution predictions, obtained through a log-likelihood analysis, fitted the results better than the predictions based on current standards, which clearly underestimated the compressive strength of SCC manufactured with fine RCA and require adjustment to take full advantage of these recycled materials. This analysis could be carried out on any type of waste and concrete, which would allow one to evaluate the same aspects as in this research and ensure that the use of recycled concrete maximizes both sustainability and strength.
Polysaccharide from Codium fragile Induces Anti-Cancer Immunity by Activating Natural Killer Cells
Authors: Park Hae-Bin , Hwang Juyoung , Zhang Wei , Go Seulgi , Kim Jihoe , Choi Inho , You SangGuan , Jin Jun-O
Published: December 2020

Natural polysaccharides exhibit beneficial immune modulatory effects, including immune stimulatory and anti-cancer activities. In this study, we examined the effect of Codium fragile polysaccharide (CFP) on natural killer (NK) cell activation, and its effect on tumor-bearing mice. Intravenous CFP treatment of C57BL/6 mice resulted in the upregulation of CD69, which is a marker associated with NK cell activation. In addition, intracellular levels of interferon (IFN)-γ and the cytotoxic mediators perforin and granzyme B were markedly increased in response to the CFP treatment of splenic NK cells. IFN-γ production by NK cells was directly induced by CFP, whereas the upregulation of CD69 and cytotoxic mediators required IL-12. Finally, intraperitoneal treatment with CFP prevented CT-26 (murine carcinoma) tumor cell infiltration in the lungs, without significantly reducing the body weight. In addition, treatment with CFP prevented B16 melanoma cell infiltration in the lung of C57BL/6 mice. Moreover, the anti-tumor effect was diminished by the depletion of NK cells. Therefore, these data suggest that CFP may be used as an NK cell stimulator to produce a phenomenon that contributes to anti-cancer immunity.
AFM Analysis of Micron and Sub-Micron Sized Bridges Fabricated Using the Femtosecond Laser on YBCO Thin Films
Authors: Umenne Patrice
Published: December 2020

The research arose as a result of the need to use the femtosecond laser to fabricate sub-micron and nano-sized bridges that could be analyzed for the Josephson effect. The femtosecond laser has a low pulse duration of 130 femtoseconds. Hence in an optical setup it was assumed that it could prevent the thermal degradation of the superconductive material during fabrication. In this paper a series of micron and sub-micron sized bridges where fabricated on superconductive yttrium barium copper oxide (YBCO) thin film using the femtosecond laser, a spherical convex lens of focal length 30 mm and the G-code control programming language applied to a translation stage. The dimensions of the bridges fabricated where analyzed using the atomic force microscope (AFM). As a result, micron sized superconductive bridges of width 1.68 μm, 1.39 μm, 1.23 μm and sub-micron sized bridges of width 858 nm, 732 nm where fabricated. The length of this bridges ranged from 9.6 μm to 12.8 μm. The femtosecond laser technique and the spherical convex lens can be used to fabricate bridges in the sub-micron dimension.
Microfluidic and Microscale Assays to Examine Regenerative Strategies in the Neuro Retina
Authors: Vazquez Maribel
Published: December 2020

Bioengineering systems have transformed scientific knowledge of cellular behaviors in the nervous system (NS) and pioneered innovative, regenerative therapies to treat adult neural disorders. Microscale systems with characteristic lengths of single to hundreds of microns have examined the development and specialized behaviors of numerous neuromuscular and neurosensory components of the NS. The visual system is comprised of the eye sensory organ and its connecting pathways to the visual cortex. Significant vision loss arises from dysfunction in the retina, the photosensitive tissue at the eye posterior that achieves phototransduction of light to form images in the brain. Retinal regenerative medicine has embraced microfluidic technologies to manipulate stem-like cells for transplantation therapies, where de/differentiated cells are introduced within adult tissue to replace dysfunctional or damaged neurons. Microfluidic systems coupled with stem cell biology and biomaterials have produced exciting advances to restore vision. The current article reviews contemporary microfluidic technologies and microfluidics-enhanced bioassays, developed to interrogate cellular responses to adult retinal cues. The focus is on applications of microfluidics and microscale assays within mammalian sensory retina, or neuro retina, comprised of five types of retinal neurons (photoreceptors, horizontal, bipolar, amacrine, retinal ganglion) and one neuroglia (Müller), but excludes the non-sensory, retinal pigmented epithelium.
Comparative Genomics of Xanthomonas citri pv. citri A* Pathotype Reveals Three Distinct Clades with Varying Plasmid Distribution
Authors: Webster John , Bogema Daniel , Chapman Toni A.
Published: December 2020

Citrus bacterial canker (CBC) is an important disease of citrus cultivars worldwide that causes blister-like lesions on host plants and leads to more severe symptoms such as plant defoliation and premature fruit drop. The causative agent, Xanthomonas citri pv. citri, exists as three pathotypes—A, A*, and Aw—which differ in their host range and elicited host response. To date, comparative analyses have been hampered by the lack of closed genomes for the A* pathotype. In this study, we sequenced and assembled six CBC isolates of pathotype A* using second- and third-generation sequencing technologies to produce complete, closed assemblies. Analysis of these genomes and reference A, A*, and Aw sequences revealed genetic groups within the A* pathotype. Investigation of accessory genomes revealed virulence factors, including type IV secretion systems and heavy metal resistance genes, differentiating the genetic groups. Genomic comparisons of closed genome assemblies also provided plasmid distribution information for the three genetic groups of A*. The genomes presented here complement existing closed genomes of A and Aw pathotypes that are publicly available and open opportunities to investigate the evolution of X. citri pv. citri and the virulence factors that contribute to this serious pathogen.
Chemical Ecology of Streptomyces albidoflavus Strain A10 Associated with Carpenter Ant Camponotus vagus
Authors: Baranova Anna A. , Chistov Alexey A. , Tyurin Anton P. , Prokhorenko Igor A. , Korshun Vladimir A. , Biryukov Mikhail V. , Alferova Vera A. , Zakalyukina Yuliya V.
Published: December 2020

Antibiotics produced by symbiotic microorganisms were previously shown to be of crucial importance for ecological communities, including ants. Previous works on ant–actinobacteria symbiosis are mainly focused on farming ants, which use antifungal microbial secondary metabolites to control pathogens in their fungal gardens. In this work, we studied microorganisms associated with carpenter ant Camponotus vagus. Pronounced antifungal activity of isolated actinobacteria strain A10 was found to be facilitated by biosynthesis of the antimycin A complex, consisting of small hydrophobic depsipeptides with high antimicrobial and cytotoxic activity. The actinomycete strain A10 was identified as Streptomyces albidoflavus. We studied the antagonistic activity of strain A10 against several entomopathogenic microorganisms. The antifungal activity of this strain potentially indicates a defensive symbiosis with the host ant, producing antimycins to protect carpenter ants against infections. The nature of this ant-microbe association however remains to be established.
Distinct Functional Traits of Lactobacilli from Women with Asymptomatic Bacterial Vaginosis and Normal Microbiota
Authors: Pramanick Rinku , Aranha Clara
Published: December 2020

Asymptomatic bacterial vaginosis (BV) in reproductive-age women has serious obstetric and gynecological consequences. Despite its high incidence, the behavior of vaginal lactobacilli in asymptomatic BV is unknown. We analyzed the functional properties of previously isolated vaginal lactobacilli from asymptomatic women with normal, intermediate, and BV microbiota. Lactic acid and antimicrobial activity against seven urogenital pathogens were evaluated from lactobacilli cell-free culture supernatants (CFCs) (n = 207) after 48 h incubation in MRS. Lactobacilli isolates were used to evaluate H2O2, autoaggregation and coaggregation with C. albicans. Lactobacilli from normal microbiota produced more d-lactate than lactobacilli from intermediate and asymptomatic BV (p = 0.007). L. plantarum, L. fermentum and L. reuteri produced greater d-lactate whereas L. rhamnosus, L. crispatus, L. johnsonii were greater producers of l-lactate. Interspecies positive correlation was observed in the lactic acid contents of CFCs. Distribution of H2O2-producing lactobacilli did not vary significantly among the groups. When lactic acid isomers were considered, species from intermediate and BV microbiota clustered together with each other and distinctly from species of normal microbiota. Broad-spectrum antagonism (≥90% inhibition) against E. coli, C. albicans, S. aureus, P. aeruginosa, G. vaginalis, N. gonorrhoeae, S. agalactiae were displayed by 46.86% (97) of isolates. Our study highlights the differential functional properties of vaginal lactobacilli from women with normal microbiota and asymptomatic BV.
Functional Amyloids Are the Rule Rather Than the Exception in Cellular Biology
Authors: Balistreri Anthony , Goetzler Emily , Chapman Matthew
Published: December 2020

Amyloids are a class of protein aggregates that have been historically characterized by their relationship with human disease. Indeed, amyloids can be the result of misfolded proteins that self-associate to form insoluble, extracellular plaques in diseased tissue. For the first 150 years of their study, the pathogen-first definition of amyloids was sufficient. However, new observations of amyloids foster an appreciation for non-pathological roles for amyloids in cellular systems. There is now evidence from all domains of life that amyloids can be non-pathogenic and functional, and that their formation can be the result of purposeful and controlled cellular processes. So-called functional amyloids fulfill an assortment of biological functions including acting as structural scaffolds, regulatory mechanisms, and storage mechanisms. The conceptual convergence of amyloids serving a functional role has been repeatedly confirmed by discoveries of additional functional amyloids. With dozens already known, and with the vigorous rate of discovery, the biology of amyloids is robustly represented by non-pathogenic amyloids.
Bioremediation by Cupriavidus metallidurans Strain MSR33 of Mercury-Polluted Agricultural Soil in a Rotary Drum Bioreactor and Its Effects on Nitrogen Cycle Microorganisms
Authors: Bravo Guillermo , Vega-Celedón Paulina , Gentina Juan Carlos , Seeger Michael
Published: December 2020

Nitrogen cycle microorganisms are essential in agricultural soils and may be affected by mercury pollution. The aims of this study are to evaluate the bioremediation of mercury-polluted agricultural soil using Cupriavidus metallidurans MSR33 in a rotary drum bioreactor (RDB) and to characterize the effects of mercury pollution and bioremediation on nitrogen cycle microorganisms. An agricultural soil was contaminated with mercury (II) (20–30 ppm) and subjected to bioremediation using strain MSR33 in a custom-made RDB. The effects of mercury and bioremediation on nitrogen cycle microorganisms were studied by qPCR. Bioremediation in the RDB removed 82% mercury. MSR33 cell concentrations, thioglycolate, and mercury concentrations influence mercury removal. Mercury pollution strongly decreased nitrogen-fixing and nitrifying bacterial communities in agricultural soils. Notably, after soil bioremediation process nitrogen-fixing and nitrifying bacteria significantly increased. Diverse mercury-tolerant strains were isolated from the bioremediated soil. The isolates Glutamicibacter sp. SB1a, Brevundimonas sp. SB3b, and Ochrobactrum sp. SB4b possessed the merG gene associated with the plasmid pTP6, suggesting the horizontal transfer of this plasmid to native gram-positive and gram-negative bacteria. Bioremediation by strain MSR33 in an RDB is an attractive and innovative technology for the clean-up of mercury-polluted agricultural soils and the recovery of nitrogen cycle microbial communities.
Fluorescence Detection of Type III Secretion Using a Glu-CyFur Reporter System in Citrobacter rodentium
Authors: Pendergrass Heather A. , Johnson Adam L. , Hotinger Julia A. , May Aaron E.
Published: December 2020

Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea worldwide. EPEC and the closely related murine model of EPEC infection, Citrobacter rodentium, utilize a type III secretion system (T3SS) to propagate the infection. Since the T3SS is not essential for the bacteria to survive or propagate, inhibiting the virulence factor with a therapeutic would treat the infection without causing harm to commensal bacteria. Studying inhibitors of the T3SS usually requires a BSL-2 laboratory designation and eukaryotic host cells while not indicating the mechanism of inhibition. We have designed a BSL-1 assay using the murine model C. rodentium that does not require mammalian cell culture. This CPG2-reporter assay allows for more rapid analysis of secretion efficiency than Western blotting and is sensitive enough to differentiate between partial and total inhibition of the T3SS. Here we present our method and the results of a small collection of compounds we have screened, including known T3SS inhibitors EGCG, regacin, and aurodox and related quorum sensing inhibitors tannic acid and ellagic acid. We have further characterized EGCG as a T3SS inhibitor and established its IC50 of 1.8 ± 0.4 μM. We also establish tannic acid as a potent inhibitor of the T3SS with an IC50 of 0.65 ± 0.09 μM.
Hydrocarbon-Degrading Bacteria Found Tightly Associated with the 50–70 μm Cell-Size Population of Eukaryotic Phytoplankton in Surface Waters of a Northeast Atlantic Region
Authors: Thompson Haydn Frank , Summers Stephen , Yuecel Raif , Gutierrez Tony
Published: December 2020

The surface of marine eukaryotic phytoplankton can harbour communities of hydrocarbon-degrading bacteria; however, this algal–bacterial association has, hitherto, been only examined with non-axenic laboratory cultures of micro-algae. In this study, we isolated an operationally-defined community of phytoplankton, of cell size 50–70 μm, from a natural community in sea surface waters of a subarctic region in the northeast Atlantic. Using MiSeq 16S rRNA sequencing, we identified several recognized (Alcanivorax, Marinobacter, Oleispira, Porticoccus, Thalassospira) and putative hydrocarbon degraders (Colwelliaceae, Vibrionaceae) tightly associated with the phytoplankton population. We combined fluorescence in situ hybridisation with flow-cytometry (FISH-Flow) to examine the association of Marinobacter with this natural eukaryotic phytoplankton population. About 1.5% of the phytoplankton population contained tightly associated Marinobacter. The remaining Marinobacter population were loosely associated with either eukaryotic phytoplankton cells or non-chlorophyll particulate material. This work is the first to show the presence of obligate, generalist and putative hydrocarbonoclastic bacteria associated with natural populations of eukaryotic phytoplankton directly from sea surface water samples. It also highlights the suitability of FISH-Flow for future studies to examine the spatial and temporal structure and dynamics of these and other algal–bacterial associations in natural seawater samples.
Physiological and Molecular Responses to Main Environmental Stressors of Microalgae and Bacteria in Polar Marine Environments
Authors: Lauritano Chiara , Rizzo Carmen , Lo Giudice Angelina , Saggiomo Maria
Published: December 2020

The Arctic and Antarctic regions constitute 14% of the total biosphere. Although they differ in their physiographic characteristics, both are strongly affected by snow and ice cover changes, extreme photoperiods and low temperatures, and are still largely unexplored compared to more accessible sites. This review focuses on microalgae and bacteria from polar marine environments and, in particular, on their physiological and molecular responses to harsh environmental conditions. The data reported in this manuscript show that exposure to cold, increase in CO2 concentration and salinity, high/low light, and/or combination of stressors induce variations in species abundance and distribution for both polar bacteria and microalgae, as well as changes in growth rate and increase in cryoprotective compounds. The use of -omics techniques also allowed to identify specific gene losses and gains which could have contributed to polar environmental adaptation, and metabolic shifts, especially related to lipid metabolism and defence systems, such as the up-regulation of ice binding proteins, chaperones and antioxidant enzymes. However, this review also provides evidence that -omics resources for polar species are still few and several sequences still have unknown functions, highlighting the need to further explore polar environments, the biology and ecology of the inhabiting bacteria and microalgae, and their interactions.
Uranium Carbide Fibers with Nano-Grains as Starting Materials for ISOL Targets
Authors: Chowdhury Sanjib , Maria Leonor , Cruz Adelaide , Manara Dario , Dieste-Blanco Olivier , Stora Thierry , Gonçalves António
Published: December 2020

This paper presents an experimental study about the preparation, by electrospinning, of uranium carbide fibers with nanometric grain size. Viscous solutions of cellulose acetate and uranyl salts (acetate, acetylacetonate, and formate) on acetic acid and 2,4-pentanedione, adjusted to three different polymer concentrations, 10, 12.5, and 15 weight %, were used for electrospinning. Good quality precursor fibers were obtained from solutions with a 15% cellulose acetate concentration, the best ones being produced from the uranyl acetate solution. As-spun precursor fibers were then decomposed by slow heating until 823 K under argon, resulting in a mixture of nano-grained UO2 and C fibers. A last carboreduction was then carried out under vacuum at 2073 K for 2 h. The final material displayed UC2−y as the major phase, with grain sizes in the 4 nm–10 nm range. UO2+x was still present in moderate concentrations (~30 vol.%). This is due to uncomplete carboreduction that can be explained by the fiber morphology, limiting the effective contact between C and UO2 grains.
Machine Learning-Assisted High-Throughput Molecular Dynamics Simulation of High-Mechanical Performance Carbon Nanotube Structure
Authors: Xiang Yi , Shimoyama Koji , Shirasu Keiichi , Yamamoto Go
Published: December 2020

Carbon nanotubes (CNTs) are novel materials with extraordinary mechanical properties. To gain insight on the design of high-mechanical-performance CNT-reinforced composites, the optimal structure of CNTs with high nominal tensile strength was determined in this study, where the nominal values correspond to the cross-sectional area of the entire specimen, including the hollow core. By using machine learning-assisted high-throughput molecular dynamics (HTMD) simulation, the relationship among the following structural parameters/properties was investigated: diameter, number of walls, chirality, and crosslink density. A database, comprising the various tensile test simulation results, was analyzed using a self-organizing map (SOM). It was observed that the influence of crosslink density on the nominal tensile strength tends to gradually decrease from the outside to the inside; generally, the crosslink density between the outermost wall and its adjacent wall is highly significant. In particular, based on our calculation conditions, five-walled, armchair-type CNTs with an outer diameter of 43.39 Å and crosslink densities (between the inner wall and outer wall) of 1.38 ± 1.16%, 1.13 ± 0.69%, 1.54 ± 0.57%, and 1.36 ± 0.35% were believed to be the optimal structure, with the nominal tensile strength and nominal Young’s modulus reaching approximately 58–64 GPa and 677–698 GPa.
Sensitive and In Situ Hemoglobin Detection Based on a Graphene Oxide Functionalized Microfiber
Authors: Fang Fang , Li Yanpeng , Yang Liuyang , Li Liangye , Yan Zhijun , Sun Qizhen
Published: December 2020

The determination of hemoglobin (Hb) level is indispensable in the pathological study of many blood diseases. Graphene oxide (GO), with its excellent optical properties and great biocompatibility, has attracted significant attention and been widely utilized in biochemical detection. Here, we report an ultrasensitive Hb sensor based on a graphene oxide (GO)-coated microfiber. The GO was utilized as a linking layer deposited on the microfiber surface, which can provide an enhanced local evanescent light field and abundant bonding sites for Hb molecules. The optical microfiber with a compact structure and a strong evanescent light field served as the platform for biosensing. The surface morphology characterized by optical microscope, scanning electron microscope, and Raman spectroscopy offers detailed evidence for the success of GO deposition. The dynamic bonding between GO and target Hb molecules was monitored in real-time through an optical spectrum analyzer. An ultrahigh sensitivity of 6.02 nm/(mg/mL) with a detection limit of 0.17 μg/mL was achieved by tracking the resonant wavelength shift of spectra. It is important to highlight that the detection limit of GO-coated microfiber is 1–2 orders of magnitude lower than other reported fiber optic Hb sensors. Benefiting from high sensitivity, low cost, small size, and fast response, the proposed sensing microfiber coated with GO could be a competitive alternative in the diagnosis of blood diseases and a subject of further research in the medical field.
Preparation and Applications of Organo-Silica Hybrid Mesoporous Silica Nanoparticles for the Co-Delivery of Drugs and Nucleic Acids
Authors: Pontón Iris , Martí del Rio Andrea , Gómez Gómez Marta , Sánchez-García David
Published: December 2020

Combination therapies rely on the administration of more than one drug, with independent mechanisms of action, aiming to enhance the efficiency of the treatment. For an optimal performance, the implementation of such therapies requires the delivery of the correct combination of drugs to a specific cellular target. In this context, the use of nanoparticles (NP) as platforms for the co-delivery of multiple drugs is considered a highly promising strategy. In particular, mesoporous silica nanoparticles (MSN) have emerged as versatile building blocks to devise complex drug delivery systems (DDS). This review describes the design, synthesis, and application of MSNs to the delivery of multiple drugs including nucleic acids for combination therapies.
Low 25-Hydroxyvitamin D Levels on Admission to the Intensive Care Unit May Predispose COVID-19 Pneumonia Patients to a Higher 28-Day Mortality Risk: A Pilot Study on a Greek ICU Cohort
Authors: Vassiliou Alice G. , Jahaj Edison , Pratikaki Maria , Orfanos Stylianos E. , Dimopoulou Ioanna , Kotanidou Anastasia
Published: December 2020

We aimed to examine whether low intensive care unit (ICU) admission 25-hydroxyvitamin D (25(OH)D) levels are associated with worse outcomes of COVID-19 pneumonia. This was a prospective observational study of SARS-CoV2 positive critically ill patients treated in a multidisciplinary ICU. Thirty (30) Greek patients were included, in whom 25(OH)D was measured on ICU admission. Eighty (80%) percent of patients had vitamin D deficiency, and the remaining insufficiency. Based on 25(OH)D levels, patients were stratified in two groups: higher and lower than the median value of the cohort (15.2 ng/mL). The two groups did not differ in their demographic or clinical characteristics. All patients who died within 28 days belonged to the low vitamin D group. Survival analysis showed that the low vitamin D group had a higher 28-day survival absence probability (log-rank test, p = 0.01). Critically ill COVID-19 patients who died in the ICU within 28 days appeared to have lower ICU admission 25(OH)D levels compared to survivors. When the cohort was divided at the median 25(OH)D value, the low vitamin D group had an increased risk of 28-day mortality. It seems plausible, therefore, that low 25(OH)D levels may predispose COVID-19 patients to an increased 28-day mortality risk.
The Effect of Low-Fat and Low-Carbohydrate Diets on Weight Loss and Lipid Levels: A Systematic Review and Meta-Analysis
Authors: Chawla Shreya , Tessarolo Silva Fernanda , Amaral Medeiros Sofia , Mekary Rania , Radenkovic Dina
Published: December 2020

Background: The rise in obesity has emphasised a focus on lifestyle and dietary habits. We aimed to address the debate between low-carbohydrate and low-fat diets and compare their effects on body weight, low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), total cholesterol, and triglycerides in an adult population. Method: Medline and Web of Science were searched for randomised controlled trials (RCTs) comparing low-fat and low-carbohydrate diets up to September 2019. Three independent reviewers extracted data. Risk of bias was assessed using the Cochrane tool. The meta-analysis was stratified by follow-up time using the random-effects models. Results: This meta-analysis of 38 studies assessed a total of 6499 adults. At 6–12 months, pooled analyses of mean differences of low-carbohydrate vs. low-fat diets favoured the low-carbohydrate diet for average weight change (mean difference −1.30 kg; 95% CI −2.02 to −0.57), HDL (0.05 mmol/L; 95% CI 0.03 to 0.08), and triglycerides (TG) (−0.10 mmol/L; −0.16 to −0.04), and favoured the low-fat diet for LDL (0.07 mmol/L; 95% CI 0.02 to 0.12) and total cholesterol (0.10 mmol/L; 95% CI 0.02 to 0.18). Conclusion and Relevance: This meta-analysis suggests that low-carbohydrate diets are effective at improving weight loss, HDL and TG lipid profiles. However, this must be balanced with potential consequences of raised LDL and total cholesterol in the long-term.
Integrative Approach to Phlebotomus mascittii Grassi, 1908: First Record in Vienna with New Morphological and Molecular Insights
Authors: Kniha Edwin , Dvořák Vít , Halada Petr , Milchram Markus , Obwaller Adelheid G. , Kuhls Katrin , Schlegel Susanne , Köhsler Martina , Poeppl Wolfgang , Bakran-Lebl Karin , Fuehrer Hans-Peter , Volfová Věra , Mooseder Gerhard , Ivovic Vladimir , Volf Petr , Walochnik Julia
Published: December 2020

Sand flies (Diptera: Psychodidae: Phlebotominae) are blood-feeding insects that transmit the protozoan parasites Leishmania spp. and various arthropod-borne (arbo) viruses. While in Mediterranean parts of Europe the sand fly fauna is diverse, in Central European countries including Austria mainly Phlebotomus mascittii is found, an assumed but unproven vector of Leishmania infantum. To update the currently understudied sand fly distribution in Austria, a sand fly survey was performed and other entomological catches were screened for sand flies. Seven new trapping locations of Ph. mascittii are reported including the first record in Vienna, representing also one of the first findings of this species in a city. Morphological identification, supported by fluorescence microscopy, was confirmed by two molecular approaches, including sequencing and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) protein profiling. Sand fly occurrence and activity were evaluated based on surveyed locations, habitat requirements and climatic parameters. Moreover, a first comparison of European Ph. mascittii populations was made by two marker genes, cytochrome c oxidase subunit 1 (COI), and cytochrome b (cytb), as well as MALDI-TOF mass spectra. Our study provides new important records of Ph. mascittii in Austria and valuable data for prospective entomological surveys. MALDI-TOF MS protein profiling was shown to be a reliable tool for differentiation between sand fly species. Rising temperatures and globalization demand for regular entomological surveys to monitor changes in species distribution and composition. This is also important with respect to the possible vector competence of Ph. mascittii.
Expanding Pharmacy Capacity for Patient-Centered Reproductive Health Services
Authors: Pfaff Anna , Rafie Sally
Published: December 2020

In the United States, patients face increasing practical barriers and concerns about stigma when seeking sexual and reproductive healthcare, specifically family planning services involving hormonal contraception, emergency contraception, and abortion. The pharmacist is a member of the interprofessional care team with the ability to provide non-judgmental, high-quality, and patient-centered care. The community pharmacy setting itself offers specific advantages which promote access, including availability in most neighborhoods, broad hours of operation, lack of need for an appointment, and a stigma-free space which is frequented for other goods and services. This commentary suggests specific ways for pharmacies to improve access to contraception, emergency contraception, and abortion in line with national quality recommendations. Particular focus is given to the intersection of sexual and reproductive health resources and referrals within the pharmacy profession as well as the training and technical assistance tools which can help address unmet patient need.
Controversies, Complexities and Contexts: Teaching Islam through Internal Feminist Critique of the Religion
Authors: Bøe Marianne Hafnor
Published: December 2020

In what ways can teaching Islam through controversial issues be useful in religious education? Can it serve to counter problems of representation of Islam, and what are the benefits and possible pitfalls of adopting such an approach? In this article, I will explore the use of Muslim internal feminist critique of conservative and patriarchal interpretations of women’s religious leadership in Islam as a controversial issues approach to teaching Islam in non-confessional religious education. The approach can be relevant for students in upper-secondary religious education, but also in teacher education. Building on secondary research documenting the problems of teaching Islam in non-confessional religious education in the Nordic countries as well as research on Muslim feminism spanning over a decade, this article investigates the didactic potentials and challenges that adopting the controversial issues approach may hold for teaching Islam. The main argument of this article is that the internal feminist debate on Islam provides an alternative entry to teaching Islam. It provides didactic resources and tools for understanding the discursive aspects of Islam, i.e., how Islam is conceived, interpreted, debated and practiced by Muslims, which in turn highlight power aspects and authority that are central to the production of religious knowledge. Consequently, the controversial issues approach may serve to counter certain “grand narratives” that seem to permeate current representations of Islam in religious education.
A Deep Learning Method for Mapping Glacial Lakes from the Combined Use of Synthetic-Aperture Radar and Optical Satellite Images
Authors: Wu Renzhe , Liu Guoxiang , Zhang Rui , Wang Xiaowen , Li Yong , Zhang Bo , Cai Jialun , Xiang Wei
Published: December 2020

Glacial lakes (GLs), a vital link between the hydrosphere and the cryosphere, participate in the local hydrological process, and their interannual dynamic evolution is an objective reflection and an indicator of regional climate change. The complex terrain and climatic conditions in mountainous areas where GLs are located make it difficult to employ conventional remote sensing observation means to obtain stable, accurate, and comprehensive observation data. In view of this situation, this study presents an algorithm with a high generalization ability established by optimizing and improving a deep learning (DL) semantic segmentation network model for extracting GL contours from combined synthetic-aperture radar (SAR) amplitude and multispectral imagery data. The aim is to use the high penetrability and all-weather advantages of SAR to reduce the effects of cloud cover as well as to integrate the multiscale and detail-oriented advantages of multispectral data to facilitate accurate, quantitative extraction of GL contours. The accuracy and reliability of the model and algorithm were examined by employing them to extract the contours of GLs in a large region of south-eastern Tibet from Landsat 8 optical remote sensing images and Sentinel-1A amplitude images. In this study, the contours of a total 8262 GLs in south-eastern Tibet were extracted. These GLs were distributed predominantly at altitudes of 4000–5500 m. Only 17.4% of these GLs were greater than 0.1 km2 in size, while a large number of small GLs made up the majority. Through analysis and validation, the proposed method was found highly capable of distinguishing rivers and lakes and able to effectively reduce the misidentification and extraction of rivers. With the DL model based on combined optical and SAR images, the intersection-over-union (IoU) score increased by 0.0212 (to 0.6207) on the validation set and by 0.038 (to 0.6397) on the prediction set. These validation data sufficiently demonstrate the efficacy of the model and algorithm. The technical means employed in this study as well as the results and data obtained can provide a reference for research and application expansion in related fields.