bluuebunny/crossref_metadata_2025 huggingface dataset:
Lead, Cadmium and Zinc Phytotoxicity Alter DNA Methylation Levels to Confer Heavy Metal Tolerance in Wheat
Authors: Shafiq Sarfraz , Zeb Qudsia , Ali Asim , Sajjad Yasar , Nazir Rashid , Widemann Emilie , Liu Liangyu
Published: September 2019

Being a staple food, wheat (Triticum aestivum) nutritionally fulfills all requirements of human health and also serves as a significant link in the food chain for the ingestion of pollutants by humans and animals. Therefore, the presence of the heavy metals such as lead (Pb) and cadmium (Cd) in soil is not only responsible for the reduction of wheat crop yield but also the potential threat for human and animal health. However, the link between DNA methylation and heavy metal stress tolerance in wheat has not been investigated yet. In this study, eight high yielding wheat varieties were screened based on their phenotype in response to Pb stress. Out of these, Pirsabak 2004 and Fakhar-e-sarhad were identified as Pb resistant and sensitive varieties, respectively. In addition, Pirsabak 2004 and Fakhar-e-sarhad varieties were also found resistant and sensitive to Cd and Zinc (Zn) stress, respectively. Antioxidant activity was decreased in Fakhar-e-sarhad compared with control in response to Pb/Cd/Zn stresses, but Fakhar-e-sarhad and Pirsabak 2004 accumulated similar levels of Pb, Cd and Zn in their roots. The expression of Heavy Metal ATPase 2 (TaHMA2) and ATP-Binding Cassette (TaABCC2/3/4) metal detoxification transporters are significantly upregulated in Pirsabak 2004 compared with Fakhar-e-sarhad and non-treated controls in response to Pb, Cd and Zn metal stresses. Consistent with upregulation of metal detoxification transporters, CG DNA hypomethylation was also found at the promoter region of these transporters in Pirsabak 2004 compared with Fakhar-e-sarhad and non-treated control, which indicates that DNA methylation regulates the expression of metal detoxification transporters to confer resistance against metal toxicity in wheat. This study recommends the farmers to cultivate Pirsabak 2004 variety in metal contaminated soils and also highlights that DNA methylation is associated with metal stress tolerance in wheat.
Special Issue “Wearable Augmented and Mixed Reality Applications”
Authors: Sanna Andrea , Manuri Federico , De Pace Francesco
Published: September 2019

Until some years ago, there was a lack of affordable devices that allowed for research in order to design and implement augmented and mixed reality applications. Thanks to technology improvements, it is now possible to find several wearable devices on the market that greatly improve the synergy between the real and virtual world, thus allowing users to be part of an immersive experience in which they can easily interact with 3D assets and real objects at the same time. Thus, the number of augmented reality and mixed reality (AR/MR) applications is greatly increased, from educational or cultural heritage applications to industry ones, such as maintenance-assembly-repair processes or product inspection and building monitoring. Indeed, several improvements have been made in order to enhance this technology, but some issues still need to be tackled, namely: limited field-of-view, tracking stability, the effectiveness of user interfaces to interact with 3D contents, and many others.
Inhibitors of Eicosanoid Biosynthesis Reveal that Multiple Lipid Signaling Pathways Influence Malaria Parasite Survival in Anopheles gambiae
Authors: Kwon Hyeogsun , Smith Ryan C.
Published: September 2019

Eicosanoids are bioactive signaling lipids derived from the oxidation of fatty acids that act as important regulators of immune homeostasis and inflammation. As a result, effective anti-inflammatory drugs have been widely used to reduce pain and inflammation which target key eicosanoid biosynthesis enzymes. Conserved from vertebrates to insects, the use of these eicosanoid pathway inhibitors offer opportunities to evaluate the roles of eicosanoids in less-characterized insect systems. In this study, we examine the potential roles of eicosanoids on malaria parasite survival in the mosquito Anopheles gambiae. Using Plasmodium oocyst numbers to evaluate parasite infection, general or specific inhibitors of eicosanoid biosynthesis pathways were evaluated. Following the administration of dexamethasone and indomethacin, respective inhibitors of phospholipid A2 (PLA2) and cyclooxygenase (COX), oocyst numbers were unaffected. However, inhibition of lipoxygenase (LOX) activity through the use of esculetin significantly increased oocyst survival. In contrast, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid (AUDA), an inhibitor of epoxide hydroxylase (EH), decreased oocyst numbers. These experiments were further validated through RNAi experiments to silence candidate genes homologous to EH in An. gambiae to confirm their contributions to Plasmodium development. Similar to the results of AUDA treatment, the silencing of EH significantly reduced oocyst numbers. These results imply that specific eicosanoids in An. gambiae can have either agonist or antagonistic roles on malaria parasite survival in the mosquito host.
Formation of Hierarchical Porous Films with Breath-Figures Self-Assembly Performed on Oil-Lubricated Substrates
Authors: Bormashenko Edward , Bormashenko Yelena , Frenkel Mark
Published: September 2019

Hierarchical honeycomb patterns were manufactured with breath-figures self-assembly by drop-casting on the silicone oil-lubricated glass substrates. Silicone oil promoted spreading of the polymer solution. The process was carried out with industrial grade polystyrene and polystyrene with molecular mass M w = 35 , 000 g m o l . Both polymers gave rise to patterns, built of micro and nano-scaled pores. The typical diameter of the nanopores was established as 125 nm. The mechanism of the formation of hierarchical patterns was suggested. Ordering of the pores was quantified with the Voronoi tessellations and calculation of the Voronoi entropy. The Voronoi entropy for the large scale pattern was S v o r = 0.6 − 0.9 , evidencing the ordering of pores. Measurement of the apparent contact angles evidenced the Cassie-Baxter wetting regime of the porous films.
Nanoparticles in Construction Materials and Other Applications, and Implications of Nanoparticle Use
Authors: Mohajerani Abbas , Burnett Lucas , Smith John V. , Kurmus Halenur , Milas John , Arulrajah Arul , Horpibulsuk Suksun , Abdul Kadir Aeslina
Published: September 2019

Nanoparticles are defined as ultrafine particles sized between 1 and 100 nanometres in diameter. In recent decades, there has been wide scientific research on the various uses of nanoparticles in construction, electronics, manufacturing, cosmetics, and medicine. The advantages of using nanoparticles in construction are immense, promising extraordinary physical and chemical properties for modified construction materials. Among the many different types of nanoparticles, titanium dioxide, carbon nanotubes, silica, copper, clay, and aluminium oxide are the most widely used nanoparticles in the construction sector. The promise of nanoparticles as observed in construction is reflected in other adoptive industries, driving the growth in demand and production quantity at an exorbitant rate. The objective of this study was to analyse the use of nanoparticles within the construction industry to exemplify the benefits of nanoparticle applications and to address the short-term and long-term effects of nanoparticles on the environment and human health within the microcosm of industry so that the findings may be generalised. The benefits of nanoparticle utilisation are demonstrated through specific applications in common materials, particularly in normal concrete, asphalt concrete, bricks, timber, and steel. In addition, the paper addresses the potential benefits and safety barriers for using nanomaterials, with consideration given to key areas of knowledge associated with exposure to nanoparticles that may have implications for health and environmental safety. The field of nanotechnology is considered rather young compared to established industries, thus limiting the time for research and risk analysis. Nevertheless, it is pertinent that research and regulation precede the widespread adoption of potentially harmful particles to mitigate undue risk.
Engineering Properties and Optimal Conditions of Cementless Grouting Materials
Authors: Lee Jaehyun , Kim Gyuyong , Kim Yongro , Mun Kyungju , Nam Jeongsoo
Published: September 2019

This study aims to analyze the engineering properties of cementless grouting materials (CGMs) and derive optimal binder types and compositions that can ensure superior material performance in comparison with ordinary Portland cement (OPC). The presented CGM is an environment-friendly inorganic binder based on ground granulated blast-furnace slag. The material properties of three CGM types with different chemical compositions were evaluated. To assess the possibility of using CGMs in grouting-construction methods, this study followed special grouting-method specifications of the J company in Korea, and tested whether CGM satisfies the performance requirements of a gel time of 20–50 s and homogel strength greater than 2 MPa after 7 days. For OPC and CGM, gel time increased and homogel strength decreased as the water/binder (W/B) ratio of Liquid B increased or as its replacement ratio decreased. Additionally, gel time decreased while homogel strength increased as the absolute weight of the Liquid B binder increased, and a negative correlation was observed between gel time and homogel strength. CGM2 was the optimal binder to ensure excellent material performance compared with OPC. Optimal mixing proportions were 117.8–167.7% W/B ratio, 42.6–56.7% Liquid B volume ratio, and 20.4–43.7 kg binder weight.
Research on the Microstructures and Mechanical Properties of Bainite/Martensite Rail Treated by the Controlled-Cooling Process
Authors: Qiu Jiajia , Zhang Min , Tan Zhunli , Gao Guhui , Bai Bingzhe
Published: September 2019

A bainite/martensite multiphase rail is treated by the controlled-cooling process with different finish-cooling temperatures. The simulated temperature–time curves of the position of 5 mm and 15 mm below the rail tread (P5 and P15) express different trends. P5 has greater impact toughness and lower tensile strength than P15. Microstructural characterization was carried out by conducting scanning electron microscopy, X-ray diffraction, electron backscatter diffraction, and transmission electron microscopy. The greater tensile strength is due to the dispersed ε-carbides hindering the movement of dislocations. The greater impact toughness is attributed to the filmy retained austenite and the smaller effective grain with high-angle boundary. Finite element modeling (FEM) and microstructural characterization reasonably explain the changes of mechanical properties. The present work provides experimental and theoretical guidance for the development of rail with excellent mechanical properties.
Toner Waste Powder (TWP) as a Filler for Polymer Blends (LDPE/HIPS) for Enhanced Electrical Conductivity
Authors: Hammani Salim , Barhoum Ahmed , Nagarajan Sakthivel , Bechelany Mikhael
Published: September 2019

Rapid urbanization proportionally increases the waste products which force humankind to find a suitable waste management system. This study aims at identifying the possibility of using toner waste powder (TWP) as a filler for fabricating polymer composites for enhanced electrical conductivity of polymer blends. TWP was successfully incorporated into a polymer blend of low-density polyethylene/high impact polystyrene (LDPE/HIPS) at a high loading percentage of up to 20 wt %. Elemental analysis (SEM-EDS and XRF) showed that the main constituents of TWP are carbon and iron with traces of other metals such as Ca, Cs, Ti, Mn, Si. The electrical conductivity of LDPE/HIPS is significantly enhanced by loading the TWP into the polymer blend. The addition of TWP to LDPE/HIPS blend decreases the electrical resistivity of the LDPE/HIPS/TWP composite to ~2.9 × 107 Ohm.cm at 10 wt % of TWP, which is several orders of magnitude lower than that of the neat blend with maintaining the thermal stability of the polymer composite. The prepared polymer composite is lightweight and shows electrical conductivity, thus it can have potential applications in electronic materials and automotive industries.
Electronic Modulation of THz Radiation at NovoFEL: Technical Aspects and Possible Applications
Authors: Shevchenko Oleg A. , Melnikov Anatoly R. , Tararyshkin Sergey V. , Getmanov Yaroslav V. , Serednyakov Stanislav S. , Bykov Evgeny V. , Kubarev Vitaly V. , Fedin Matvey V. , Veber Sergey L.
Published: September 2019

The Novosibirsk Free Electron Laser (NovoFEL) facility is able to produce high-power tunable terahertz (THz) laser radiation in quasi-continuous mode. The ability to control/shape this THz radiation is required in a number of user experiments. In this work we propose a modulation approach suitable for free electron lasers based on recuperation design. It allows for generating THz macropulses of a desirable length, down to several microseconds (limited by a quality factor of FEL optical resonator). Using this approach, macropulses in the time window from several microseconds to several hundred microseconds have been shown for three possible frequency ranges: mid-infrared (~1100 cm−1), far-infrared (~200 cm−1) and THz (~40 cm−1). In each case, the observed rise and decay of the macropulse have been measured and interpreted. The advantage of using short macropulses at the maximum peak power available has been demonstrated with the time-resolved Electron Paramagnetic Resonance (EPR) spectroscopy.
Contactless Manipulation of Soft Robots
Authors: Kim Jae Gwang , Park Jeong Eun , Won Sukyoung , Jeon Jisoo , Wie Jeong Jae
Published: September 2019

In recent years, jointless soft robots have demonstrated various curvilinear motions unlike conventional robotic systems requiring complex mechanical joints and electrical design principles. The materials employed to construct soft robots are mainly programmable anisotropic polymeric materials to achieve contactless manipulation of miniaturized and lightweight soft robots through their anisotropic strain responsivity to external stimuli. Although reviews on soft actuators are extensive, those on untethered soft robots are scant. In this study, we focus on the recent progress in the manipulation of untethered soft robots upon receiving external stimuli such as magnetic fields, light, humidity, and organic solvents. For each external stimulus, we provide an overview of the working principles along with the characteristics of programmable anisotropic materials and polymeric composites used in soft robotic systems. In addition, potential applications for untethered soft robots are discussed based on the physicochemical properties of programmable anisotropic materials for the given external stimuli.
The Effect of Y/Er and Zn Addition on the Microstructure and Mechanical Properties of Mg-11Li Alloy
Authors: Zhang Mingquan , Zhang Jinghuai , Wu Ruizhi , Cui Hongwei , Zhao Ertuan , Liu Shujuan , Qin Pengfei , Ji Qing
Published: September 2019

Although body-centered cubic (BCC) structural magnesium–lithium (Mg-Li) alloys have lower density and better formability than common hexagonal close-packed (HCP) Mg alloys, their applications remain limited due to their low strength. The purpose of this study is to investigate the effect of Y/Er and Zn addition on the microstructure and tensile properties of Mg-11Li alloy with a BCC structural matrix by comparing Mg-11Li, Mg-11Li-4Y-2Er-2Zn, and Mg-11Li-8Y-4Er-4Zn (wt %) alloys. The results indicate that the addition of Y/Er and Zn at a ratio of 3:1 cannot promote the formation of long-period stacking ordered structure in Mg-11Li alloy such as that in Mg-Y-Er-Zn alloys and the dominant intermetallic phases formed are BCC Mg24RE5 and face-centered cubic (FCC) Mg3RE2Zn3 phases. With an increase of the content of Y/Er and Zn in an as-cast alloy, the fraction of intermetallic particles increases and the grain size decreases. The addition of Y/Er, as well as Zn, dramatically promotes the refinement of dynamic recrystallization (DRX) during extrusion. The initial intermetallic phases induced by Y/Er and Zn addition are broken into relatively fine particles during extrusion, and this contributes to refining the dynamic recrystallized (DRXed) grains mainly by the particle stimulated nucleation mechanism. The as-extruded Mg-11Li-4Y-2Er-2Zn and Mg-11Li-8Y-4Er-4Zn alloys exhibit much higher tensile strength as compared with as-extruded Mg-11Li alloy, which is mainly ascribed to the refined DRXed grains and numerous dispersed intermetallic phase particles. It is suggested that further refinement of intermetallic particles in these extruded Mg-11Li-based alloys may lead to higher quality alloy materials with low density and excellent mechanical properties.
Characterization of the Elastoplastic Response of Low Zn-Cu-Ti Alloy Sheets Using the CPB-06 Criterion
Authors: Alister Francisco , Celentano Diego , Signorelli Javier , Bouchard Pierre-Olivier , Pino Daniel , Cruchaga Marcela
Published: September 2019

Unlike other HCP metals such as titanium and magnesium, the behavior of zinc alloys has only been modeled in the literature. For the low Zn-Cu-Ti alloy sheet studied in this work, the anisotropy is clearly seen on the stress-strain curves and Lankford coefficients. These features impose a rigorous characterization and an adequate selection of the constitutive model to obtain an accurate representation of the material behavior in metal forming simulations. To describe the elastoplastic behavior of the alloy, this paper focuses on the material characterization through the application of the advanced Cazacu-Plunket-Barlat 2006 (CPB-06 for short) yield function combined with the well-known Hollomon hardening law. To this end, a two-stage methodology is proposed. Firstly, the material characterization is performed via tensile test measurements on sheet samples cut along the rolling, diagonal and transverse directions in order to fit the parameters involved in the associate CPB-06/Hollomon constitutive model. Secondly, these material parameters are assessed and validated in the simulation of the bulge test using different dies. The results obtained with the CPB-06/Hollomon model show a good agreement with the experimental data reported in the literature. Therefore, it is concluded that this model represents a consistent approach to estimate the behavior of Zn-Cu-Ti sheets under different forming conditions.
Methods for Congenital Thumb Hypoplasia Reconstruction. A Review of the Outcomes for Ten Years of Surgical Treatment
Authors: Ozols Dzintars , Butnere Marisa Maija , Petersons Aigars
Published: September 2019

Background and objectives: Congenital thumb hypoplasia is a rare deformity of upper extremity. The incidence for thumb hypoplasia grade II–V is 1:10,000 newborns per year in Latvia. A technique for extensor indicis proprius (EIP) tendon transfer with subperiosteal fixation was developed and used for thumb hypoplasia grades II and IIIa. Pollicization or second-toe-to-hand transplantation with metatarsophalangeal (MTP) joint arthrodesis was used for the reconstruction of hypoplasia grade IIIb–V. The aim of this retrospective cohort study is to evaluate the outcomes for reconstruction techniques used in one surgical center during a ten-year period by one surgeon to evaluate functional and aesthetical outcomes for new techniques. Materials and Methods: In total, 21 patients were operated on during 2007–2017, and 18 of these patients were involved in this study. Long-term follow-up was completed to evaluate the functions and aesthetics of the hands. Results: disabilities of the arm, shoulder and hand (DASH) was 9.35 (8–10.7) for the second-toe-to-hand with MTP joint arthrodesis transplantation method for pollicization method 19.8 (6–26.7), and for the EIP tendon transposition, 14.54 (0.9–56.3). Conclusions: The postoperative functional parameters of congenital hand hypoplasia patients, regardless of the surgical method, are worse than the functional results of healthy patients. The use of the second-toe-to-hand with MTP joint arthrodesis transplantation method provides patients with congenital hand IIIb–V hypoplasia a stable and functional first finger formation. The functional results are comparable to the clinical results of the pollicization method while ensuring the creation of a five-digit hand.
Subclinical Atrial Fibrillation and Risk of Stroke: Past, Present and Future
Authors: AlTurki Ahmed , Marafi Mariam , Russo Vincenzo , Proietti Riccardo , Essebag Vidal
Published: September 2019

Subclinical atrial fibrillation (SCAF) describes asymptomatic episodes of atrial fibrillation (AF) that are detected by cardiac implantable electronic devices (CIED). The increased utilization of CIEDs renders our understanding of SCAF important to clinical practice. Furthermore, 20% of AF present initially as a stroke event and prolonged cardiac monitoring of stroke patients is likely to uncover a significant prevalence of SCAF. New evidence has shown that implanting cardiac monitors into patients with no history of atrial fibrillation but with risk factors for stroke will yield an incidence of SCAF approaching 30–40% at around three years. Atrial high rate episodes lasting longer than five minutes are likely to represent SCAF. SCAF has been associated with an increased risk of stroke that is particularly significant when episodes of SCAF are greater than 23 h in duration. Longer episodes of SCAF are incrementally more likely to progress to episodes of SCAF >23 h as time progresses. While only around 30–40% of SCAF events are temporally related to stroke events, the presence of SCAF likely represents an important risk marker for stroke. Ongoing trials of anticoagulation in patients with SCAF durations less than 24 h will inform clinical practice and are highly anticipated. Further studies are needed to clarify the association between SCAF and clinical outcomes as well as the factors that modify this association.
Antipyretic, Antinociceptive, and Anti-Inflammatory Activities from Pogostemon benghalensis Leaf Extract in Experimental Wister Rats
Authors: Aryal Sushant , Adhikari Balkrishna , Panthi Kasmira , Aryal Pramod , Mallik Shyam Kumar , Bhusal Ram Prasad , Salehi Bahare , Setzer William N. , Sharifi-Rad Javad , Koirala Niranjan
Published: September 2019

Background: Pogostemon benghalensis leaves have traditionally been utilized for relieving body aches, headaches and fever. Based on its uses, the present study was designed to investigate the antinociceptive, antipyretic and anti-edematogenic activities from P. benghalensis leaves’ methanol extract (PBME) in Wister rats. Methods: The thermal (hot plate) and chemical (acetic acid-induced writhing and formalin test) models for antinociceptive effects, and the Brewer’s yeast induced hyperthermia test for antipyretic action and rat paw edema by carrageenan for anti-edematogenic activity, were applied for PBME at different dose levels. The acute toxicity of PBME through the oral route was performed to determine the lethal dose. Results: PBME significantly and dose-dependently reduced pyrexia and diminished edema volume, which depicted its antipyretic and anti-edematogenic effects respectively. The inhibition of writhing reflex, increased reaction latency and reduced frequency of licking indicated that PBME has significant dose-dependent antinociceptive activity. P. benghalensis methanol extract at 4000 mg/kg shows no sign of toxicity, which is a considerable, good margin of safety. Conclusions: The study illustrated the antipyretic, antinociceptive and anti-inflammatory potential of P. benghalensis leaf extract with a safety margin, and validated its traditional use to alleviate fever, pain, and inflammation.
Current Understanding of Methamphetamine-Associated Metabolic Changes Revealed by the Metabolomics Approach
Authors: Kim Minjeong , Jang Won-Jun , Shakya Rupa , Choi Boyeon , Jeong Chul-Ho , Lee Sooyeun
Published: September 2019

Metabolomics is a powerful tool used in the description of metabolic system perturbations caused by diseases or abnormal conditions, and it usually involves qualitative and/or quantitative metabolome determination, accompanied by bioinformatics assessment. Methamphetamine is a psychostimulant with serious abuse potential and due to the absence of effective pharmacotherapy and a high recurrence potential, methamphetamine addiction is a grave issue. Moreover, its addiction mechanisms remain unclear, probably due to the lack of experimental models that reflect personal genetic variances and environmental factors determining drug addiction occurrence. The metabolic approach is only recently being used to study the metabolic effects induced by a variety of methamphetamine exposure statuses, in order to investigate metabolic disturbances related to the adverse effects and discover potential methamphetamine addiction biomarkers. To provide a critical overview of methamphetamine-associated metabolic changes revealed in recent years using the metabolomics approach, we discussed methamphetamine toxicity, applications of metabolomics in drug abuse and addiction studies, biological samples used in metabolomics, and previous studies on metabolic alterations in a variety of biological samples—including the brain, hair, serum, plasma, and urine—following methamphetamine exposure in animal studies. Metabolic alterations observed in animal brain and other biological samples after methamphetamine exposure were associated with neuronal and energy metabolism disruptions. This review highlights the significance of further metabolomics studies in the area of methamphetamine addiction research. These findings will contribute to a better understanding of metabolic changes induced by methamphetamine addiction progress and to the design of further studies targeting the discovery of methamphetamine addiction biomarkers and therapeutic targets.
Serum Levels of Mitochondrial and Microbial Metabolites Reflect Mitochondrial Dysfunction in Different Stages of Sepsis
Authors: Beloborodova Natalia , Pautova Alisa , Sergeev Aleksandr , Fedotcheva Nadezhda
Published: September 2019

Mechanisms of mitochondrial dysfunction in sepsis are being extensively studied in recent years. During our study, concentrations of microbial phenolic acids and mitochondrial metabolites (succinic, α-ketoglutaric, fumaric, itaconic acids) as indicators of sepsis and mitochondrial dysfunction, respectively, are measured by gas chromatography–mass spectrometry (GC–MS) in the blood of critically ill patients at the early and late stages of documented sepsis. The increase in levels of some phenylcarboxylic (phenyllactic (PhLA), p-hydroxyphenylacetic (p-HPhAA), p-hydroxyphenyllactic (p-HPhAA)) acids (PhCAs), simultaneously with a rise in levels of mitochondrial dicarboxylic acids, are mainly detected during the late stage of sepsis, especially succinic acid (up to 100–1000 µM). Itaconic acid is found in low concentrations (0.5–2.3 µM) only at early-stage sepsis. PhCAs in vitro inhibits succinate dehydrogenase (SDH) in isolated mitochondria but, unlike itaconic acid which acts as a competitive inhibitor of SDH, microbial metabolites most likely act on the ubiquinone binding site of the respiratory chain. A close correlation of the level of succinic acid in serum and sepsis-induced organ dysfunction is revealed, moreover the most significant correlation is observed at high concentrations of phenolic microbial metabolites (PhCAs) in late-stage sepsis. These data indicate the promise of such an approach for early detection, monitoring the progression of organ dysfunction and predicting the risk of non-survival in sepsis.
Advancement of Peptide Nanobiotechnology via Emerging Microfluidic Technology
Authors: Chan Kiat Hwa , Tay Jonathan Jen Jie
Published: September 2019

Peptide nanotechnology has experienced a long and enduring development since its inception. Many different applications have been conceptualized, which depends on the functional groups present on the peptide and the physical shape/size of the peptide nanostructures. One of the most prominent nanostructures formed by peptides are nanoparticles. Until recently, however, it has been challenging to engineer peptide nanoparticles with low dispersity. An emerging and promising technique involves the utility of microfluidics to produce a solution of peptide nanoparticles with narrow dispersity. In this process, two or more streams of liquid are focused together to create conditions that are conducive towards the formation of narrowly dispersed samples of peptide nanoparticles. This makes it possible to harness peptide nanoparticles for the myriad of applications that are dependent on nanoparticle size and uniformity. In this focus review, we aim to show how microfluidics may be utilized to (1) study peptide self-assembly, which is critical to controlling nanostructure shape and size, and peptide-interface interactions, and (2) generate self-assembling peptide-based microgels for miniaturized cell cultures. These examples will illustrate how the emerging microfluidic approach promises to revolutionize the production and application of peptide nanoparticles in ever more diverse fields than before.
Arsenic (As) Removal Using Talaromyces sp. KM-31 Isolated from As-Contaminated Mine Soil
Authors: Nam In-Hyun , Murugesan Kumarasamy , Ryu Jungho , Kim Jae Hwan
Published: September 2019

Bioremediation is an environmentally-benign and cost-effective approach to removing arsenic from contaminated areas. A fungal strain hyper-tolerant to arsenic was isolated from soil from a mine site and used for the removal of arsenic. The isolated fungus was identified as Talaromyces sp., and its growth rate, arsenic tolerance, and removal rates were investigated for As(III) and As(V). Arsenic tolerance tests revealed that the fungus was highly resistant to arsenic, tolerating concentrations up to 1000 mg/L. Robust mycelial growth was observed in potato dextrose broth containing either As(III) or As(V), and there was no difference in growth between that in arsenic-free medium and medium amended with up to 300 mg/L of either arsenic species. The isolate showed relatively low growth rates at As(V) concentrations >500 mg/L, and almost no growth at As(III) concentrations >300 mg/L. Both arsenic species were effectively removed from aqueous medium (>70%) in tests of the biosorption of arsenic onto mycelial biomass. Surface modification of the biomass with Fe(III) (hydr)oxides significantly enhanced arsenic removal efficiency. The findings indicate that this soil fungal strain has promise for use in bioremediation strategies to remove arsenic from highly contaminated aqueous systems.
Methodological Approach to Reconstructing Lost Monuments from Archaeological Findings: The San Francesco di Castelletto Church in Genoa
Authors: Scrivano Simona , Gaggero Laura , Volpe Elisa
Published: September 2019

Throughout history, natural hazards, wars, political changes and urban evolution have contributed to the obliteration of outstanding monuments. The study of their remains, frequently recovered as archaeological findings, can be the basis for a reconstruction of the lost structures, by way of their size, function, decoration and stylistic evolution. The present study developed a multidisciplinary approach to gather and interpret archaeological fragments and archive sources, in order to gain as much information as possible on “lost monuments”. The approach was tested with remnants (i.e., several hundreds of marble fragments found during archaeological excavations) of the monastic complex of San Francesco di Castelletto (Genoa), which was demolished after the Napoleonic suppressions. A preliminary organisation of the sample set was attained through cataloguing shape, size, and decoration. After this, a comparison with similar complexes still existing in Genoa allowed the inference of the age and specific ornamental functions for the majority of the pieces. Surface analysis, carried out in situ (portable microscope) and on micro-samples (petrographic analysis and SEM-EDS), allowed the characterisation of the materials (e.g., assessing marble provenance and identifying pigments). As a whole, the method evolved into an operational protocol, which helped both the organisation of the archaeological findings and the reconstruction of unknown phases of the lost monument.
Sintering Optimisation and Recovery of Aluminum and Sodium from Greek Bauxite Residue
Authors: Tam Pritii Wai Yin , Panias Dimitrios , Vassiliadou Vicky
Published: September 2019

Bauxite residue is treated for the recovery of aluminum and sodium by sintering with the addition of soda, metallurgical coke and other reagents such as CaO, MgO and BaO. A thorough thermodynamic analysis using Factsage 7.0™ software was completed together with XRD mineralogy of sinters with different fluxes and reagents additions. Through both thermodynamic interpretation and mineralogical confirmations, it was observed that the type of desilication product in bauxite residue influences the total aluminum recovery through the sintering process and formation of sodium aluminum silicate exists in equilibrium with sodium aluminate, unless silica is consumed by additives (such as CaO, MgO, BaO etc.) forming other more thermodynamically favorable species and liberating alumina. Addition of barium oxide improves the aluminum and sodium recovery to 75% and 94% respectively. Complex sinter product formation that are triggered due to high calcium content in the Greek bauxite residue reduces aluminum recovery efficiency. Optimised and feasible recovery of aluminum and sodium for Greek bauxite residue was proved to be 70% and 85% respectively, when sintered with 50% excess stoichiometric soda. It was observed that stoichiometric carbon addition in inert atmosphere only assisted recovery up to 75% of aluminum and 83% of sodium, though there are benefits gained from pre-reducing iron from hematite for downstream recovery.
Fabrication of Durable Ordered Ta2O5 Nanotube Arrays Decorated with Bi2S3 Quantum Dots
Authors: Baluk Mateusz A. , Kobylański Marek P. , Lisowski Wojciech , Trykowski Grzegorz , Klimczuk Tomasz , Mazierski Paweł , Zaleska-Medynska Adriana
Published: September 2019

One of the most important challenges in the fabrication of ordered tantalum pentaoxide (Ta2O5) nanotube arrays (NTs) via the electrochemical method is the formation of nanotubes that adhere well to the Ta substrate. In this paper, we propose a new protocol that allows tight-fitting Ta2O5 nanotubes to be obtained through the anodic oxidation of tantalum foil. Moreover, to enhance their activity in the photocatalytic reaction, in this study, they have been decorated by nontoxic bismuth sulfide (Bi2S3) quantum dots (QDs) via a simple successive ionic layer adsorption and reaction (SILAR) method. Transmission electron microscopy (TEM) analysis revealed that quantum dots with a size in the range of 6–11 nm were located both inside and on the external surfaces of the Ta2O5 NTs. The effect of the anodization time and annealing conditions, as well as the effect of cycle numbers in the SILAR method, on the surface properties and photoactivity of Ta2O5 nanotubes and Bi2S3/Ta2O5 composites have been investigated. The Ta2O5 nanotubes decorated with Bi2S3 QDs exhibit high photocatalytic activity in the toluene degradation reaction, i.e., 99% of toluene (C0 = 200 ppm) was degraded after 5 min of UV-Vis irradiation. Therefore, the proposed anodic oxidation of tantalum (Ta) foil followed by SILAR decorating allows a photocatalytic surface, ready to use for pollutant degradation in the gas phase, to be obtained.
Mono-6-Deoxy-6-Aminopropylamino-β-Cyclodextrin on Ag-Embedded SiO2 Nanoparticle as a Selectively Capturing Ligand to Flavonoids
Authors: Hahm Eunil , Kang Eun Ji , Pham Xuan-Hung , Jeong Daham , Jeong Dae Hong , Jung Seunho , Jun Bong-Hyun
Published: September 2019

It has been increasingly important to develop a highly sensitive and selective technique that is easy to handle in detecting levels of beneficial or hazardous analytes in trace quantity. In this study, mono-6-deoxy-6-aminopropylamino-β-cyclodextrin (pr-β-CD)-functionalized silver-assembled silica nanoparticles (SiO2@Ag@pr-β-CD) for flavonoid detection were successfully prepared. The presence of pr-β-CD on the surface of SiO2@Ag enhanced the selectivity in capturing quercetin and myricetin among other similar materials (naringenin and apigenin). In addition, SiO2@Ag@pr-β-CD was able to detect quercetin corresponding to a limit of detection (LOD) as low as 0.55 ppm. The relationship between the Raman intensity of SiO2@Ag@pr-β-CD and the logarithm of the Que concentration obeyed linearity in the range 3.4–33.8 ppm (R2 = 0.997). The results indicate that SiO2@Ag@pr-β-CD is a promising material for immediately analyzing samples that demand high sensitivity and selectivity of detection.
Bacterial Cellulose: Production, Modification and Perspectives in Biomedical Applications
Authors: Gorgieva Selestina , Trček Janja
Published: September 2019

Bacterial cellulose (BC) is ultrafine, nanofibrillar material with an exclusive combination of properties such as high crystallinity (84%–89%) and polymerization degree, high surface area (high aspect ratio of fibers with diameter 20–100 nm), high flexibility and tensile strength (Young modulus of 15–18 GPa), high water-holding capacity (over 100 times of its own weight), etc. Due to high purity, i.e., absence of lignin and hemicellulose, BC is considered as a non-cytotoxic, non-genotoxic and highly biocompatible material, attracting interest in diverse areas with hallmarks in medicine. The presented review summarizes the microbial aspects of BC production (bacterial strains, carbon sources and media) and versatile in situ and ex situ methods applied in BC modification, especially towards bionic design for applications in regenerative medicine, from wound healing and artificial skin, blood vessels, coverings in nerve surgery, dura mater prosthesis, arterial stent coating, cartilage and bone repair implants, etc. The paper concludes with challenges and perspectives in light of further translation in highly valuable medical products.
The Effect of 12 Weeks of β-Hydroxy-β-Methyl-Butyrate Supplementation after Liver Transplantation: A Pilot Randomized Controlled Study
Authors: Lattanzi Barbara , Giusto Michela , Albanese Carlina , Mennini Gianluca , D’Ambrosio Daria , Farcomeni Alessio , Ginanni Corradini Stefano , Rossi Massimo , Merli Manuela
Published: September 2019

Sarcopenia is a frequent complication in liver transplant (LT) recipients. β-hydroxy-β-methyl-butyrate (HMB) has the potential to increase muscle-performance and tropism. Our study aims at evaluating the effect on muscle mass and functioning, and the safety of 12 weeks of HMB supplementation in patients after LT. This is a pilot, randomized study. Male patients undergoing LT were randomly assigned to the HMB or control group. A diet interview, anthropometry and body composition by dual energy X-ray absorptiometry (DEXA) were performed at enrollment (T0), after 12 weeks (T1) and after 12 months (T12). Twenty-two liver transplant male patients were enrolled in the study: 12 in the HMB group and 10 as the control group. At enrollment, demographic, clinical and nutritional data were similar. According to the appendicular skeletal muscle index, sarcopenia was present in 50% of patients. The appendix skeletal muscle mass index (ASMI) showed a significant increase at T1 and T12 in HMB patients, but not in controls. The mid-arm muscle-circumference and hand grip strength also increased at T1 and T12 versus T0 only in the HMB group. No side effects were reported in either group. The study showed a positive effect of HMB in the recovery of muscle mass and strength after LT. HMB supplement in patients after LT was safe and well tolerated.
Energy Intake and Severity of Dementia Are Both Associated with Health-Related Quality of Life among Older Long-Term Care Residents
Authors: KS Salminen , MH Suominen , H Kautiainen , HM Roitto , KH Pitkala
Published: September 2019

Our aim was to investigate how energy intake modifies the association of the stage of dementia with health related quality of life (HRQoL) among institutionalized older people. A cross-sectional sample of 538 older long-term care residents with dementia in Helsinki, Finland were assessed with HRQoL (15D), energy intake (from one to two days), and the stage of dementia by the clinical dementia rating (CDR) scale. The energy intakes were standardized by z-scores to include both men and women in the same analyses. Severity of dementia was associated with HRQoL (15D index in CDR 0.5–1: 0.65 (0.11), CDR 2: 0.60 (0.10), CDR 3: 0.52 (0.10)). When the three groups of dementia severity were divided according to their energy intake quartiles, there was an association between the HRQoL and the stage of dementia (p < 0.001) and energy intake (p = 0.013); however, no interaction was observed (p = 0.30). While partial correlation analysis showed that energy intake correlated with HRQoL among residents with very mild/mild or moderate dementia, this was not observed among those with severe dementia. In moderate dementia, the dimensions of mobility and usual activities correlated significantly with higher energy intake. Both energy intake and severity of dementia are associated with HRQoL.
Allium hookeri Root Extract Inhibits Adipogenesis by Promoting Lipolysis in High Fat Diet-Induced Obese Mice
Authors: Kim Hyun Ju , Lee Min-Jung , Jang Ja-Young , Lee Sung-Hyen
Published: September 2019

Allium hookeri (AH) is widely consumed as a herbal medicine. It possesses biological activity against metabolic diseases. The objective of this study was to investigate effects of AH root water extract (AHR) on adipogenesis in 3T3-L1 cells and in high-fat diet (HFD)-induced obese mice. AHR inhibited lipid accumulation during adipocyte differentiation by downregulation of gene expression, such as hormone sensitive lipase (HSL), lipoprotein lipase (LPL) and an adipogenic gene, CCAAT/enhancer binding protein-α in 3T3-L1 preadipocytes. Oral administration of AHR significantly suppressed body weight gain, adipose tissue weight, serum leptin levels, and adipocyte cell size in HFD-induced obese mice. Moreover, AHR significantly decreased hepatic mRNA expression levels of cholesterol synthesis genes, such as 3-hydroxy-3-methylglutaryl CoA reductase, sterol regulatory element-binding transcription factor (SREBP)-2, and low-density lipoprotein receptor, as well as fatty acid synthesis genes, such as SREBP-1c and fatty acid synthase. Serum triglyceride levels were also lowered by AHR, likely as a result of the upregulating gene involved in fatty acid β-oxidation, carnitine palmitoyltransferase 1a, in the liver. AHR treatment activated gene expression of peroxisome proliferator-activated receptor-γ, which might have promoted HSL and LPL-medicated lipolysis, thereby reducing white adipose tissue weight. In conclusion, AHR treatment can improve metabolic alterations induced by HFD in mice by modifying expression levels of genes involved in adipogenesis, lipogenesis, and lipolysis in the white adipose tissue and liver.
Astragalus polysaccharides (PG2) Enhances the M1 Polarization of Macrophages, Functional Maturation of Dendritic Cells, and T Cell-Mediated Anticancer Immune Responses in Patients with Lung Cancer
Authors: Bamodu Oluwaseun Adebayo , Kuo Kuang-Tai , Wang Chun-Hua , Huang Wen-Chien , Wu Alexander T.H. , Tsai Jo-Ting , Lee Kang-Yun , Yeh Chi-Tai , Wang Liang-Shun
Published: September 2019

Background: Recently, we demonstrated that Astragalus polysaccharide (PG2), the active ingredient in dried roots of astragalus membranaceus, ameliorates cancer symptom clusters and improves quality of life (QoL) in patients with metastatic disease by modulating inflammatory cascade against the background roles of inflammatory cells, including macrophages, dendritic cells (DCs), and cytotoxic T lymphocytes (CTLs) in tumor initiation, metastasis, and progression. Nevertheless, the role of PG2 in the modulation of anticancer immunogenicity and therapeutic response remains relatively underexplored and unclear. Purpose: The present study investigates how and to what extent PG2 modulates cellular and biochemical components of the inflammatory cascade and enhances anticancer immunity, as well as the therapeutic implication of these bio-events in patients with lung cancer. Methods and Results: Herein, we demonstrated that PG2 significantly increased the M1/M2 macrophage polarization ratio in non-small cell carcinoma (NSCLC) H441 and H1299 cells. This PG2-induced preferential pharmacologic up-regulation of tumoral M1 population in vitro positively correlated with the downregulation of tumor-promoting IL-6 and IL-10 expression in NSCLC cell-conditioned medium, with concomitant marked inhibition of cell proliferation, clonogenicity, and tumorsphere formation. Our ex vivo results, using clinical sample from our NSCLC cohort, demonstrated that PG2 also promoted the functional maturation of DCs with consequent enhancement of T cell-mediated anticancer immune responses. Consistent with the in vitro and ex vivo results, our in vivo studies showed that treatment with PG2 elicited significant time-dependent depletion of the tumor-associated M2 population, synergistically enhanced the anti-M2-based anticancer effect of cisplatin, and inhibited xenograft tumor growth in the NSCLC mice models. Moreover, in the presence of PG2, cisplatin-associated dyscrasia and weight-loss was markedly suppressed. Conclusion: These results do indicate a therapeutically-relevant role for PG2 in modulating the M1/M2 macrophage pool, facilitating DC maturation and synergistically enhancing the anticancer effect of conventional chemotherapeutic agent, cisplatin, thus laying the foundation for further exploration of the curative relevance of PG2 as surrogate immunotherapy and/or clinical feasibility of its use for maintenance therapy in patients with lung cancer.
Association of Day-to-Day Variations in Physical Activity with Postprandial Appetite Regulation in Lean Young Males
Authors: Ando Takafumi , Higuchi Mitsuru , Tanaka Shigeho
Published: September 2019

Previous studies have shown that habitual physical activity improves postprandial appetite regulation. We evaluated the direct association between physical activity level (PAL) and postprandial appetite regulation, and the effect of day-to-day variations in PAL on improving postprandial appetite regulation in lean young males. Fourteen young male adults wore a triaxial accelerometer for at least 6 consecutive days to evaluate their PAL. Two random liquid preload tests were performed on separate days to evaluate the competence of postprandial appetite regulation. In the preload test, participants ate sandwiches ad libitum 75 min after drinking one of two liquids containing different energy densities. When a participant had an adequate regulation of their postprandial appetite, the difference in energy intake from sandwiches was expected to be close to the energy gap between both liquids. Average daily PAL (r = −0.558, p < 0.05), but not the SD of PAL, which is indicative of the day-to-day variations in PAL (r = −0.437, p > 0.1), correlated with the difference in energy intake from the sandwiches. In addition, higher average PAL was closer to the energy gap between the two liquids. These results suggest that average daily PAL, rather than day-to-day variations in PAL, predicts inter-individual variation in postprandial appetite regulation, at least for lean young males.