Search results for: cell free supernatant

Authors: Yilin Ma, Zhaomiao Liu, Xiang Wang, Yan Pang

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Microscale droplets play an increasingly important role in various applications, including medical diagnostics, material synthesis, chemical engineering, and cell research due to features of high surface-to-volume ratio and tiny scale, which can significantly improve reaction rates, enhance heat transfer efficiency, enable high-throughput parallel studies as well as reduce reagent usage. As a mature technique to manipulate small amounts of liquids, droplet microfluidics could achieve the precise control of droplet parameters such as size, uniformity, structure, and thus has been widely adopted in the engineering and scientific research of multiple fields. Necking processes of the droplet in the cross junction microchannels are experimentally and theoretically investigated and dynamic mechanisms of the neck thinning in two different regimes are revealed. According to evolutions of the minimum neck width and the thinning rate, the necking process is further divided into different stages and the main driving force during each stage is confirmed. Effects of the flow rates and the cross-sectional aspect ratio on the necking process as well as the neck profile at different stages are provided in detail. The distinct features of the two regimes in the squeezing stage are well captured by the theoretical estimations of the effective flow rate and the variations of the actual flow rates in different channels are reasonably reflected by the channel width ratio. In the collapsing stage, the quantitative relation between the minimum neck width and the remaining time is constructed to identify the physical mechanism.

Keywords: cross junction, neck thinning, force analysis, inertial mechanism

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Authors: Anju Joshi, C. N. Tharamani

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Diabetes is one of the leading cause of death at present and remains an important concern as the prevalence of the disease is increasing at an alarming rate. Therefore, it is crucial to diagnose the accurate levels of glucose for developing an efficient therapeutic for diabetes. Due to the availability of convenient and compact self-testing, continuous monitoring of glucose is feasible nowadays. Enzyme based electrochemical sensing of glucose is quite popular because of its high selectivity but suffers from drawbacks like complicated purification and immobilization procedures, denaturation, high cost, and low sensitivity due to indirect electron transfer. Hence, designing a robust enzyme free platform using transition metal oxides remains crucial for the efficient and sensitive determination of glucose. In the present work, manganese doped nickel oxide nanoparticles (Mn-NiO) has been synthesized onto the surface of multiwalled carbon nanotubes using a simple microwave assisted approach for non-enzymatic electrochemical sensing of glucose. The morphology and structure of the synthesized nanostructures were characterized using scanning electron microscopy (SEM) and X-Ray diffraction (XRD). We demonstrate that the synthesized nanostructures show enormous potential for electrocatalytic oxidation of glucose with high sensitivity and selectivity. Cyclic voltammetry and square wave voltammetry studies suggest superior sensitivity and selectivity of Mn-NiO decorated carbon nanotubes towards the non-enzymatic determination of glucose. A linear response between the peak current and the concentration of glucose has been found to be in the concentration range of 0.01 μM- 10000 μM which suggests the potential efficacy of Mn-NiO decorated carbon nanotubes for sensitive determination of glucose.

Keywords: diabetes, glucose, Mn-NiO decorated carbon nanotubes, non-enzymatic

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Authors: Ling Xu, Giuseppe Loprencipe, Antonio D'Andrea

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Asphalt pavement with recycled and sustainable materials has become the most commonly adopted strategy for road construction, including reclaimed asphalt pavement (RAP) and crumb rubber (CR) from waste tires. However, the adhesion and cohesion characteristics of rubberized reclaimed asphalt pavement were still ambiguous, resulting in deteriorated adhesion behavior and life performance. This research investigated the effect of bonding characteristics on rutting resistance and moisture susceptibility of rubberized reclaimed asphalt pavement in terms of two RAP sources with different oxidation levels and two tire rubber with different particle sizes. Firstly, the binder bond strength (BBS) test and bonding failure distinguishment were conducted to analyze the surface behaviors of binder-aggregate interaction. Then, the compatibility and penetration grade of rubberized RAP binder were evaluated by rotational viscosity test and penetration test, respectively. Hamburg wheel track (HWT) test with high-temperature viscoelastic deformation analysis was adopted, which illustrated the rutting resistance. Additionally, a water boiling test was employed to evaluate the moisture susceptibility of the mixture and the texture features were characterized with the statistical parameters of image colors. Finally, the colloid structure model of rubberized RAP binder with surface interaction was proposed, and statistical analysis was established to release the correlation among various indexes. This study concluded that the gel-phase colloid structure and molecular diffusion of the free light fraction would affect the surface interpretation with aggregate, determining the bonding characteristic of rubberized RAP asphalt.

Keywords: bonding characteristics, reclaimed asphalt pavement, rubberized asphalt, sustainable material

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Authors: Solange Adechian, Michèle Balage, Didier Remond, Carole Migné, Annie Quignard-Boulangé, Agnès Marset-Baglieri, Sylvie Rousset, Yves Boirie, Claire Gaudichon, Dominique Dardevet, Laurent Mosoni

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Studies have shown that timing of protein intake, leucine content, and speed of digestion significantly affect postprandial protein utilization. Our aim was to determine if one can spare lean body mass during energy restriction by varying the quality and the timing of protein intake. Obese volunteers followed a 6-wk restricted energy diet. Four groups were compared: casein pulse, casein spread, milk-soluble protein (MSP, = whey) pulse, and MSP spread (n = 10-11 per group). In casein groups, caseins were the only protein source; it was MSP in MSP groups. Proteins were distributed in four meals per day in the proportion 8:80:4:8% in the pulse groups; it was 25:25:25:25% in the spread groups. We measured weight, body composition, nitrogen balance, 3-methylhistidine excretion, perception of hunger, plasma parameters, adipose tissue metabolism, and whole body protein metabolism. Volunteers lost 7.5 ± 0.4 kg of weight, 5.1 ± 0.2 kg of fat, and 2.2 ± 0.2 kg of lean mass, with no difference between groups. In adipose tissue, cell size and mRNA expression of various genes were reduced with no difference between groups. Hunger perception was also never different between groups. In the last week, due to a higher inhibition of protein degradation and despite a lower stimulation of protein synthesis, postprandial balance between whole body protein synthesis and degradation was better with caseins than with MSP. It seems likely that the positive effect of caseins on protein balance occurred only at the end of the experiment.

Keywords: lean body mass, fat mass, casein, whey, protein metabolism

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Authors: Debasmita Mukhopadhyay, Manika Pal Bhadra

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MiRNAs contribute to oncogenesis either as tumor suppressors or oncogenes. Hence, discovery of miRNA-based therapeutics are imperative to ameliorate cancer. Modulation of miRNA maturation is accomplished via several therapeutic agents, including small molecules and oligonucleotides. Due to the attractive pharmacokinetic properties of small molecules over oligonucleotides, we set to identify small molecule inhibitors of a metastasis-inducing microRNA. Cytotoxicity profile of aza-flavanone C1 was analyzed in a panel of breast cancer cells employing the NCI-60 screen protocols. Flow cytometry, immunofluorescence and western blotting of apoptotic or EMT markers were performed to analyze the effect of C1. A dual luciferase assay unequivocally suggested that C1 repressed endogenous miR-10b in MDA-MB-231 cells. A derivative of aza-flavanone C1 is shown as a strong inhibitor miR-10b. Blockade of miR-10b by C1 resulted in decreased expression of miR-10b targets in an aggressive breast cancer cell line model, MDA-MB-231. Abrogation of TWIST1, an EMT-inducing transcription factor also contributed to C1 mediated apoptosis. Moreover C1 exhibited a specific and selective down-regulation of miR-10b and did not function as a general inhibitor of miRNA biogenesis or other oncomiRs of breast carcinoma. Aza-flavanone congener C1 functions as a potent inhibitor of the metastasis-inducing microRNA, miR-10b. Our present study provides evidence for targeting metastasis-inducing microRNA, miR-10b with a derivative of Aza-flavanone. Better pharmacokinetic properties of small molecules place them as attractive agents compared to nucleic acids based therapies to target miRNA. Further work, in generating analogues based on aza-flavanone moieties will significantly improve the affinity of the small molecules to bind miR-10b. Finally, it is imperative to develop small molecules as novel miRNA-therapeutics in the fight against cancer.

Keywords: breast cancer, microRNA, metastasis, EMT

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Authors: Calvin Stephen, Biswajit Basu, Aonghus McNabola

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Market liberalization in the power sector has led to the emergence of micro-hydropower schemes that are dependent on the use of pumps-as-turbines in applications that were not suitable as potential hydropower sites in earlier years. These applications include energy recovery in water supply networks, sewage systems, irrigation systems, alcohol breweries, underground mining and desalination plants. As a result, there has been an accelerated adoption of pumpsas-turbine technology due to the economic advantages it presents in comparison to the conventional turbines in the micro-hydropower space. The performance of this machines under cavitation conditions, however, is not well understood as there is a deficiency of knowledge in literature focused on their turbine mode of operation. In hydraulic machines, cavitation is a common occurrence which needs to be understood to safeguard them and prolong their operation life. The overall purpose of this study is to investigate the effects of cavitation on the performance of a pumps-as-turbine system over its entire operating range. At various operating speeds, the cavitating region is identified experimentally while monitoring the effects this has on the power produced by the machine. Initial results indicate occurrence of cavitation at higher flow rates for lower operating speeds and at lower flow rates at higher operating speeds. This implies that for cavitation free operation, low speed pumps-as-turbine must be used for low flow rate conditions whereas for sites with higher flow rate conditions high speed turbines should be adopted. Such a complete understanding of pumps-as-turbine suction performance can aid avoid cavitation induced failures hence improved reliability of the micro-hydropower plant.

Keywords: cavitation, micro-hydropower, pumps-as-turbine, system design

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Authors: Hyun Lim, Dong Sook Min, Han Eul Yun, Kil Tae Kim, Ya Nan Sun, Young Ho Kim, Hyun Pyo Kim

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Matrix metalloproteinase (MMP)-13 has an important role for degrading cartilage materials under inflammatory conditions such as arthritis. Since the 70% ethanol extract of Acanthopanax koreanum inhibited MMP-13 expression in IL-1β-treated human chondrocyte cell line, SW1353, two major constituents including acanthoic acid and impressic acid were initially isolated from the same plant materials and their MMP-13 down-regulating capacity was examined. In IL-1β-treated SW1353 cells, acanthoic acid and impressic acid significantly and concentration-dependently inhibited MMP-13 expression at 10 – 100 μM and 0.5 – 10 μM, respectively. The potent one, impressic acid, was found to inhibit MMP-13 expression by blocking the phosphorylation of signal transducer and activator of transcription-1/-2 (STAT-1/-2) and activation of c-Jun and c-Fos among cellular signaling pathway involved, but did not affect the activation of mitogen-activated protein kinases (MAPKs) and nuclear transcription factor-κB (NF-κB). Further, impressic acid was also found to inhibit the expression of MMP-13 mRNA (47.7% inhibition at 10 μM), the glycosaminoglycan release (42.2% reduction at 10 μM) and proteoglycan loss in IL-1-treated rabbit cartilage explants culture. For a further study, 21 impressic acid derivatives were isolated from the same plant materials and their suppressive activities against MMP-13 expression were examined. Among the derivatives, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F and acantrifoside A clearly down-regulated MMP-13 expression, but impressic acid being most potent. All these results suggest that impressic acid, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F, acantrifoside A and A. koreanum may have a potential for therapeutic agents to prevent cartilage degradation possibly by inhibiting matrix protein degradation.

Keywords: acanthoic acid, Acanthopanax koreanum, cartilage, impressic acid, matrix metalloproteinase

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Authors: G. De Matteis, L. Martina, V. Turco

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The work is focused on determining and comparing special nonlinear static configurations in cholesteric liquid crystals (CLCs), confined between two parallel plates and in the presence of an external static electric/magnetic field. The solutions are stabilised by topological and non-topological conservation laws since they are described in terms of integrable or partially integrable nonlinear boundary value problems. In cholesteric liquid crystals which are subject to geometric frustration; anchoring conditions at boundaries, i.e., homeotropic conditions, are incompatible with the cholesteric twist. This aspect turns out to be essential in the admissible classes of solutions, allowing also for disclination type singularities. Within the framework of Frank-Oseen theory, we study the static configurations for CLCs. First, we find numerical solutions for isolated axisymmetric states in confined CLCs with weak homeotropic anchoring at the boundaries. These solutions describe 3-dimensional modulations, namely spherulites or cholesteric bubbles, actually observed in these systems, of standard baby skyrmions. Relations with well-known nonlinear integrable systems are found and are used to explore the asymptotic behavior of the solutions. Then we turn our attention to extended periodic static configurations called Helicoids or cholesteric fingers, described by an elliptic sine-Gordon model with appropriate boundary conditions, showing how their period and energies are determined by both the thickness of the cell and the intensity of the external electric/magnetic field. We explicitly show that helicoids with π or 2π of rotations of the molecular director are different in many aspects and are not simply algebraically related. The behaviour of the solutions, their energy and the properties of the associated disclinations are discussed in detail, both analytically and numerically.

Keywords: cholesteric liquid crystals, geometric frustration, helicoids, skyrmions

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Authors: Rehab F. Abdel-Rahman, Sally A. El Awdan, Rehab R. Hegazy, Dina F. Mansour, Hanan A. Ogaly, Marwan Abdelbaset

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Disorders of the cerebral circulation are the leading cause of numerous neurological and psychiatric illnesses. The transient middle cerebral artery occlusion model (MCAO) is considered to be a reliable and reproducible rodent model of cerebral ischemia. The purpose of the current study was to examine the neuroprotective effects of Crocus sativus (saffron) in a rat model of left middle cerebral artery MCAO. Male Wistar rats were anesthetized and subjected to 1 h of MCAO followed by 48 h reperfusion or sham surgery. One group of the ischemia operated animals was kept as left brain ischemia/reperfusion (I/R). Another 2 operated groups received saffron extract (100 or 200 mg/kg, i.p) four times (60 min before the surgery, during the surgery, and on days 1 and 2 after the occlusion). During the experiment, behavioral tests were performed. After 72 h the animals were euthanized and their left brain hemispheres were used in the biochemical, histopathological, and immunohistochemical studies. Saffron administration revealed an improvement in I/R-induced alteration of locomotor balance and coordination ability of rats. Moreover, saffron decreased the brain content of malondialdehyde, nitric oxide, brain natriuretic peptide and vascular endothelial growth factor with significant increase of reduced glutathione. Immunohistochemical evaluation of caspase-3 and Bax protein expression revealed reduction in I/R-enhanced apoptosis in saffron treated rats. In conclusion, saffron treatment decreases ischemic brain injury in association with inhibition of apoptotic and oxidative cell death in a dose dependent manner.

Keywords: caspase-3, cerebral ischemia, Crocus sativus, rats, vascular endothelial growth factor

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Authors: Armend Kelmendi, Adnan Ahmeti

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The purpose of our study was to assess the impact of soccer in the overall wealth fare (education, health, and economic prosperity) of youth in Kosovo (age: 7-18). The research conducted measured a number of parameters (training methodologies, conditions, community leadership impact) in a sample consisting of 6 different football clubs’ academies across the country. Fifty (50) male and female football youngsters volunteered in this study. To generate more reliable results, the analysis was conducted with the help of a set of effective project management tools and techniques (Gantt chart, Logic Network, PERT chart, Work Breakdown Structure, and Budgeting Analysis). The interviewees were interviewed under a specific lens of categories (impact in education, health, and economic prosperity). A set of questions were asked i.e. what has football provided to you and the community you live in?; Did football increase your confidence and shaped your life for better?; What was the main reason you started training in football? The results generated explain how a single sport, namely that of football in Kosovo can make a huge social change, improving key social factors in a society. There was a considerable difference between the youth clubs as far as training conditions are concerned. The study found out that despite financial constraints, two out of six clubs managed to produce twice as more talented players that were introduced to professional primary league teams in Kosovo and Albania, including other soccer teams in the region, Europe, and Asia. The study indicates that better sports policy must be formulated and associated with important financial investments in soccer for it to be considered fruitful and beneficial for players of 18 plus years of age, namely professionals.

Keywords: youth, prosperity, conditions, investments, growth, free movement

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Authors: Ali Faisal Saleem, Farheen Quadri, Mach Ondrej, Anita Zaidi

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Purpose: Pakistan is the final frontier for a polio-free world. Chronic malnutrition is associated with lack of effective gut immunity, and possibly associated with poliomyelitis in children received multiple OPV. We evaluate IPV dose administered together with OPV results in higher immunogenicity and mucosal immunity compared to OPV alone in chronically malnourished infants. Methods AND Materials: A community-based, unblinded-randomized-trial, conducted in 5 peri-urban, low-middle-income households of Karachi, in infants 9-12 months. Two study groups were non-malnourished (HAZ= -2 or more) and chronic malnourished (HAZ <-2SD), with 2-arms each i) OPV and ii) OPV and IPV. Two blood specimens (2ml) at baseline and at day 28 and two stool specimens (6 gm.) at day 29 and after 7 days. All infants received a bOPV challenge dose after first stool specimen. Calculates sample size was 210 in each arm. Serological (baseline compared to 28 days post-vaccine) and mucosal immunity after one week of bOPV challenge dose were study outcomes. Results: Baseline seroprevalence in malnourished infants were low compared to non-malnourished (P1, P2 and P3 (p=<0.001). There is significant rise in antibody titer and P1 seroprevalence in Mal A and B after receiving study vaccine; much higher in Mal B. Infants randomized to bOPV + IPV study vaccine showed incremental immune response against P1 (Mal B, 92.2%; Nor B, 98.4%), P2 (Mal B, 90.4%; Nor B, 94.7%), and P3 (Mal B, 85.6% and Nor B, 93.5%) was observed. A significant proportion of infants in malnourished (P1, 13%; P2, 24%; P3, 26%) and normally nourished group (P1, 5%; P2, 11%; P3, 14%) were found to be seronegative at baseline. Infants who received BOPV + IPV as their study vaccine showed a very high seroconversion response after vaccine (p=<0.001 for P1, P2 and P3). Majority of the specimens were negative at baseline (Mal A, 2%, Mal B, 1%; Nor A, 2%; Nor B, 1%), and remains negative after bOPV challenge dose (Mal A, 8%, Mal B, 6%; Nor A, 11%; Nor B, 10%). Conclusion: Malnourished-infants have low poliovirus-seroprevalence that increased remarkably after IPV. There is less viral shedding after IPV in infants.

Keywords: chronic malnutrition, infants, IPV, OPV

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Authors: Anthony John Walker, Glen Bright

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The challenge faced by manufactures, when producing custom products, is that each product needs exact components. This can cause work-in-process instability due to component matching constraints imposed on assembly cells. Clearing type flow control policies have been used extensively in mediating server access between multiple arrival processes. Although the stability and performance of clearing policies has been well formulated and studied in the literature, the growth in arrival to departure sequence disorder for each arriving job, across a serving resource, is still an area for further analysis. In this paper, a closed form industrial model has been formulated that characterizes arrival-to-departure sequence disorder through stable manufacturing systems under clearing type flow control policy. Specifically addressed are the effects of sequence disorder imposed on a downstream assembly cell in terms of work-in-process instability induced through component matching constraints. Results from a simulated manufacturing system show that steady state average sequence disorder in parallel upstream processing cells can be balanced in order to decrease downstream assembly system instability. Simulation results also show that the closed form model accurately describes the growth and limiting behavior of average sequence disorder between parts arriving and departing from a manufacturing system flow controlled via clearing policy.

Keywords: assembly system constraint, custom products, discrete sequence disorder, flow control

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Authors: Chetna Tyagi. G. B. V. S. Lakshmi, Ambuj Tripathi, D. K. Avasthi

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Graphene oxide provides a good host matrix for preparing nanocomposites due to the different functional groups attached to its edges and planes. Being biocompatible, it is used in therapeutic applications. As enzyme-based biosensor requires complicated enzyme purification procedure, high fabrication cost and special storage conditions, we need enzyme-less biosensors for use even in a harsh environment like high temperature, varying pH, etc. In this work, we have prepared both enzyme-based and enzyme-less graphene oxide-based biosensors for glucose detection using glucose-oxidase as enzyme and gold nanoparticles, respectively. These samples were characterized using X-ray diffraction, UV-visible spectroscopy, scanning electron microscopy, and transmission electron microscopy to confirm the successful synthesis of the working electrodes. Electrochemical measurements were performed for both the working electrodes using a 3-electrode electrochemical cell. Cyclic voltammetry curves showed the homogeneous transfer of electron on the electrodes in the scan range between -0.2V to 0.6V. The sensing measurements were performed using differential pulse voltammetry for the glucose concentration varying from 0.01 mM to 20 mM, and sensing was improved towards glucose in the presence of gold nanoparticles. Gold nanoparticles in graphene oxide nanocomposite played an important role in sensing glucose in the absence of enzyme, glucose oxidase, as evident from these measurements. The selectivity was tested by measuring the current response of the working electrode towards glucose in the presence of the other common interfering agents like cholesterol, ascorbic acid, citric acid, and urea. The enzyme-less working electrode also showed storage stability for up to 15 weeks, making it a suitable glucose biosensor.

Keywords: electrochemical, enzyme-less, glucose, gold nanoparticles, graphene oxide, nanocomposite

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Authors: Sirwe Ghaderpour, Nasrollah Ahmadifard, Naser Agh, Zakaria Vahabzadeh

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Rotifers are used in many hatcheries for feeding the earliest stages of fish larvae and crustaceans due to their small size, slow movements, fast reproduction, and easy cultivation. One of the disadvantages of using rotifers as live prey is their lower content of some nutrients compared to copepods, so it is necessary to increase the amounts of these nutrients by means of enrichment. Minerals are a group of micro-elements, essential to fish, that is lacking in the rotifers, for example, selenium (30 fold) and zinc (5 fold) are present in lower quantities than the minimum amounts found in copepods. In this study, the condensed Isochrysis aff. galbana (T-ISO) and Nannochloropsis oculata were suspended at concentration of 18 × 109 cell mL⁻¹ of water with 20 ppt of salinity. Four different levels (0, 1000, 2000, and 4000 mg L⁻¹) of each Na₂SeO₃ and ZnSO₄.7H₂O separately were prepared, and 1 mL of each stock was poured to the algae enrichment vessels for 1 h simultaneously. After that, the material was centrifuged (at 4000 rpm for 5 min), and the precipitated enriched algae was used for rotifer feeding. The contents of Se, Zn, Cu, and Mn were determined in enriched microalgae and rotifer by Atomic absorption. The highest content of both minerals was observed in 0.4 Zn + 0.4 Se treatment and also rotifer enriched with these enriched microalgae. The enrichment of microalgae with Zn and Se does not affect the content of Cu in the microalgae. Also, the content of Cu in rotifer fed with the enriched microalgae showed the highest Cu content in the treatments than the control. But, the enrichment with both minerals had a negative effect on the content Mn in enriched mixed microalgae except 0.4 Zn + 0.4 Se. The Mn content in enriched rotifer decreased in the treatments than the control except for 0.1 Zn + 0.1 Se. There was no significant effect on rotifer growth in combined enrichment with both minerals (p < 0.05). Overall, rotifers enrichment with Se and Zn mixed microalgae resulted in increasing Se, Zn, and Cu. This will allow Se and Zn microalgae enriched rotifers to be used as the minerals delivery method for fish larvae nutritional requirements.

Keywords: enrichment, larvae, microalgae, mineral, rotifer

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Authors: Abinash Tripathy, Girish Muralidharan, Amitava Pramanik, Prosenjit Sen

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Superhydrophobic surfaces are abundant in nature. Several surfaces such as wings of butterfly, legs of water strider, feet of gecko and the lotus leaf show extreme water repellence behaviour. Self-cleaning, stain-free fabrics, spill-resistant protective wears, drag reduction in micro-fluidic devices etc. are few applications of superhydrophobic surfaces. In order to design robust superhydrophobic surface, it is important to understand the interaction of water with superhydrophobic surface textures. In this work, we report a simple coating method for creating large-scale flexible superhydrophobic paper surface. The surface consists of multiple layers of silanized zirconia microparticles decorated with zirconia nanoparticles. Water contact angle as high as 159±10 and contact angle hysteresis less than 80 was observed. Drop impact studies on superhydrophobic paper surface were carried out by impinging water droplet and capturing its dynamics through high speed imaging. During the drop impact, the Weber number was varied from 20 to 80 by altering the impact velocity of the drop and the parameters such as contact time, normalized spread diameter were obtained. In contrast to earlier literature reports, we observed contact time to be dependent on impact velocity on superhydrophobic surface. Total contact time was split into two components as spread time and recoil time. The recoil time was found to be dependent on the impact velocity while the spread time on the surface did not show much variation with the impact velocity. Further, normalized spreading parameter was found to increase with increase in impact velocity.

Keywords: contact angle, contact angle hysteresis, contact time, superhydrophobic

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Authors: Elisa Negretto

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Improvisation is a fundamental form of musical practice and an increasing amount of literature shows a particular interest on the consequences it might have in different kinds of social contexts. A relevant aspect of the musical experience is the ability to create expectations, which reflects a basic strategy of the human mind, an intentional movement toward the future which is based on previous experiences. Musical Expectation – an unconscious tendency to project forward in time, to predict future sound events and the ongoing of a musical experience – can be regarded as a process that strongly influences the listeners’ emotional and affective response to music, as well as their social and aesthetic experience. While improvising, composers, interpreters and listeners generate and exchange expectations, thus creating a dynamic dialogue and meaningful relationships. The aim of this paper is to investigate how expectation contributes to the creation of such a dialogue during the unfolding of the musical experience and to what extent it influences the meaning music acquires during the performance. The difference between the ability to create expectations and the anticipation of the future ongoing of music will be questioned. Does it influence in different ways the meaning of music and the kind of dialogical relationship established between musicians and between performers and audience? Such questions will be investigated with reference to recent research in music cognition and the analysis of a particular case: a free jazz performance during which musicians improvise and/or change the location of the sound source. The present paper is an attempt to provide new insights for investigating and understanding the cognitive mechanisms underlying improvisation as a musical and social practice. They contribute to the creation of a model that we can find in many others social practices in which people have to build meaningful relationships and responses to environmental stimuli.

Keywords: anticipation, expectation, improvisation, meaning, musical dialogue

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Authors: Seyda Tugba Gunday Anil, Ayhan Bozkurt

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Next generation lithium batteries are taking more attention and single-ion polymer electrolytes are expected to play a significant role in the development of these kinds of energy storage systems. In the present work we used a different strategy to design of novel solid single-ion conducting inorganic polymer electrolytes based on lithium polyvinyl alcohol oxalate borate (Li(PVAOB), lithium polyacrylic acid oxalate borate (LiPAAOB) and poly (ethylene glycol) methacrylate (PEGMA). Free radical polymerization was used to convert PEGMA into PPEGMA and LiPAAOB is prepared from poly (acrylic acid), oxalic acid and boric acid. Blend polymer electrolytes were produced by mixing of LiPAAOB or Li (PVAOB with PPEGMA at different stoichiometric ratios to enhance the single ion conductivity of the systems. To exploit the flexible chemistry and increase the segmental mobility of the blend electrolyte, the composition was changed up to 80% with respect to the guest polymer, PPEGMA. FT-IR and differential scanning calorimeter techniques confirmed the interaction between the host and guest polymers. TGA verified that the thermal stability of the blends increased up to approximately 200 C. Scanning electron microscopy images confirm the homogeneity of the blend electrolytes. CV studies showed that electrochemical stability electrochemical stability window is approximately 5 V versus Li/Li⁺. The effect of PPEGMA on to the Lithium-ion conductivity was investigated using dielectric impedance analyzer. The maximum single ion conductivity was measured as 1.3 × 10⁻⁴ S/cm at 100 C for the sample LiPAAOB-80PPEGMA. Clearly, the results confirmed the positive effect to the increment in ionic conductivity of the blend electrolytes with the addition of PPEGMA.

Keywords: single-ion conductor, inorganic polymer, blends, polymer electrolyte

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Authors: Inese Tenberga

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Undoubtedly, the focus of the present capitalist system of finance has shifted from the concept of productivity of money to the ‘cult of money’, which is characterized by such notions as speculative activity, squander, self-profit, vested interest, etc. The author is certain that a civilized society cannot follow this economic path any longer and therefore suggests that one solution would be to integrate the Islamic financial model in the banking sector of the EU to overcome its economic vulnerability and structurally transform its economies or build resilience against shocks and crisis. The researcher analyses the Islamic financial model, which is providing the basis for the concept of non-productivity of money, and proposes to consider it as a new paradigm of economic thinking. The author argues that it seeks to establish a broad-based economic well-being with an optimum rate of economic growth, socio-economic justice, equitable distribution of income and wealth. Furthermore, the author analyses and proposes to use the experience of member states of the Islamic Development Bank for the formation of a new EU interest free banking. It is offered to create within the EU banking system a credit sector and investment sector respectively. As a part of the latter, it is recommended to separate investment banks specializing in speculative investments and non­speculative investment banks. Meanwhile, understanding of the idea of Islamic banking exclusively from the perspective of the manner of yielding profit that differs from credit banking, without considering the legal, social, ethical guidelines of Islam impedes to value objectively the advantages of this type of financial activities at the non-Islamic jurisdictions. However, the author comes to the conclusion the imperative of justice and virtue, which is inherent to all of us, exists regardless of religion. The author concludes that the global community should adopt the experience of the Muslim countries and focus on the Islamic banking model.

Keywords: credit sector, EU banking system, investment sector, Islamic banking

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Authors: Ansah Iris Baffour, Dong-Ho Kim, Sung-Gyu Park

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The ongoing COVID-19 pandemic, caused by the SARS-CoV-2 virus and is gradually shifting to an endemic phase which implies the outbreak is far from over and will be difficult to eradicate. Global cooperation has led to unified precautions that aim to suppress epidemiological spread (e.g., through travel restrictions) and reach herd immunity (through vaccinations); however, the primary strategy to restrain the spread of the virus in mass populations relies on screening protocols that enable rapid on-site diagnosis of infections. Herein, we employed surface enhanced Raman spectroscopy (SERS) for the rapid detection of SARS-CoV-2 lysate on an Au-modified Au nanodimple(AuND)electrode. Through in situone-pot Au electrodeposition on the AuND electrode, Au-lysate nanocomposites were synthesized, generating3D internal hotspots for large SERS signal enhancements within 30 s of the deposition. The capture of lysate into newly generated plasmonic nanogaps within the nanocomposite structures enhanced metal-spike protein contact in 3D spaces and served as hotspots for sensitive detection. The limit of detection of SARS-CoV-2 lysate was 5 x 10-2 PFU/mL. Interestingly, ultrasensitive detection of the lysates of influenza A/H1N1 and respiratory syncytial virus (RSV) was possible, but the method showed ultimate selectivity for SARS-CoV-2 in lysate solution mixtures. We investigated the practical application of the approach for rapid on-site diagnosis by detecting SARS-CoV-2 lysate spiked in normal human saliva at ultralow concentrations. The results presented demonstrate the reliability and sensitivity of the assay for rapid diagnosis of COVID-19.

Keywords: label-free detection, nanocomposites, SARS-CoV-2, surface-enhanced raman spectroscopy

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Authors: Shaima A. Al Mansoori

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Eco-cities have become part of the broader and universal discourse and embrace of sustainable communities. Given the ideals and ‘potential’ benefits of eco-cities for people, the environment and prosperity, hardly can an argument be made against the desirability of eco-cities. Yet, this paper posits that it is necessary for urban scholars, technocrats and policy makers to engage in discussions of the pragmatism of implementing the ideals of eco-cities, for example, from the political, budgetary, cultural and other dimensions. In the context of such discourse, this paper examines the feasibility of one of the cardinal principles and goals of eco-cities, which is the reduction or elimination of pollution through various creative and innovative initiatives, in the UAE. This paper contends and argues that, laudable and desirable as this goal is, it is a polylemma and, therefore, overly ambitious and practically unattainable in the UAE. The paper uses the mixed method research strategy, in which data is sourced from secondary and general sources through desktop research, from public records in governmental agencies, and from the conceptual academic and professional literature. Information from these sources will be used, first, to define and review pollution as a concept and multifaceted phenomenon with multidimensional impacts. Second, the paper will use society’s five goal clusters as a framework to identify key causes and impacts of pollution in the UAE. Third, the paper will identify and analyze specific public policies, programs and projects that make pollution in the UAE a polylemma. Fourth, the paper will argue that the phenomenal rates of population increase, urbanization, economic growth, consumerism and development in the UAE make pollution an inevitable product and burden that society must live with. This ‘reality’ makes the goal and desire of pollution-free cities pursuable but unattainable. The paper will conclude by identifying and advocating creative and innovative initiatives that can be taken by the various stakeholders in the country to reduce and mitigate pollution in the short- and long-term.

Keywords: goal clusters, pollution, polylemma, sustainable communities

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Authors: Lawan Ja’afar Tahir

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This research work centered on the problem of free Arms flow around the Nigeria and Chad Border. The whole of the northeastern Nigerian region has been devastated by the crisis of insecurity facilitated by more than a decade of insurgency. One of the major issues of concern to security experts and personnel in the country is how the insurgents are getting access to weapons, which gave them more strength to fight the war for this long period, which has become so difficult to overcome. Among the possible avenues that continue to strengthen the enemies is the easy access to the arms flow from the neighboring countries, especially the Republic of Chad, which borders Nigeria to the east, where Boko Haram gained firm roots. This paper, therefore, looked at the nature of the waterway of the Nigeria/Chad Border, which has become a source of strength to the insurgents as the flow of weapons is one of the cheapest things on the Border. The availability of such arms flow has also led to the People abandoning their lands and economic and commercial activities, especially those settlements between the Border of these two countries. For more than eight years now, they have suspended their livelihood activities, roads were blocked and chances of survival in the rural areas were minimal due to the frequent attacks carried out by the insurgents. However, this research looks at the causes of the arms flow along the Border of these neighboring countries, the extent of damage done as a result of the availability of the weapons, and how far the Nigerian government has gone in curtailing the menace of the flow of dangerous weapons into the country. The research looked at the ways arm dealers are conniving with settlers along the border as well as the various ways they followed to reach their target. The work provided suggestion as to how the fragile Border should be managed with the view to reduce the influx of arms without control, which, according to this research, is the central factor that continues to unleash and give terror groups the opportunity to destroy people for more than a decade.

Keywords: border, insecurity, weapons, management

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Authors: Saleh Alzahrani

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The studies in the field of International Comparative Education in the Arabic world and the middle east are scarcity. However, some International Comparative Education Researchers and post graduates face a challenge concerning of a selection of a distinguished study to improve their national education system. It requires a considerable effort. According to that, the matrix of scientific research in comparative and international education is designed to help specialists, researchers and graduate students in generating a variety of research ideas in a short time in this field. The matrix is built by using content analysis method of comparative education research published in the Arab journals from 1980 to 2017. Then, qualitative input with the in-depth focus analysis tool is utilized according to the root theory. The matrix consists of two axes; vertical (X) and horizontal (Y). The number of fields in the vertical axis are 6 domains, including 105 variables. The horizontal axis is two fields which are pre-university education that incorporate educational stages and contemporary formulations including (23) variables. The second field is the university education in its public universities and contemporary formulas including (15) variables. The researcher can access topics, ideas and research points through the matrix of scientific research in comparative and international education by selecting of any subject on the vertical axis (X) from (1) to (105) and selecting of any subject on the horizontal axis (Y) from (B) to (U). The cell where the axes intersect with the chosen fields can generate an idea or a research point conveniently and easily through the words that have been monitored by the user. These steps can be repeated to generate new ideas and research points. Many graduate researchers have been trained on using of this matrix which gave them more potential to generate an appropriate study serving the national education.

Keywords: content analysis method, comparative education, international education, matrix, root theory

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Authors: Ashley DelCorno

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GEM Anscombe’s 1958 essay Modern Moral Philosophy and the tradition of virtue ethics that followed has given rise to the restoration (or, more plainly, the resurrection) of Aristotle as something of an authority figure. Alisdair MacIntyre and Martha Nussbaum are proponents, for example, not just of Aristotle’s relevancy but also of his apparent implicit authority. That said, it’s not clear that the schema imagined by virtue ethicists accurately describes moral life or that it does not inadvertently work to impoverish genuine decision-making. If the label ‘virtue’ is categorically denied to some groups (while arbitrarily afforded to others), it can only turn on itself, thus rendering ridiculous its own premise. Likewise, as an inescapable feature of virtue ethics, Aristotelean binaries like ‘virtue/vice’ and ‘voluntary/involuntary’ offer up false dichotomies that may seriously compromise an agent’s ability to conceptualize choices that are truly free and rooted in meaningful criteria. Here, this topic is analyzed through a feminist lens predicated on the known paradoxes of patriarchy. The work of feminist theorists Jacqui Alexander, Katharine Angel, Simone de Beauvoir, bell hooks, Audre Lorde, Imani Perry, and Amia Srinivasan serves as important guideposts, and the argument here is built from a key tenet of black feminist thought regarding scarcity and possibility. Above all, it’s clear that though the philosophical tradition of virtue ethics presents itself as recovering the place of agency in ethics, its premises possess crippling limitations toward the achievement of this goal. These include, most notably, virtue ethics’ binding analysis of history, as well as its axiomatic attachment to obligatory clauses, problematic reading-in of Aristotle and arbitrary commitment to predetermined and competitively patriarchal ideas of what counts as a virtue.

Keywords: feminist history, the limits of utopic imagination, curatorial creation, truth, virtue, freedom

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Authors: Tiziana Biasutti, Daniela Rigamonti, Lorenzo Palmiotti, Adelaide Nespoli, Paolo Bettini

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Aerospace industry is based on the continuous development of new technologies and solutions that allows constant improvement of the systems. Shape Memory Alloys are smart materials that can be used as dampers due to their pseudoelastic effect. The purpose of the research was to design a passive damper in Nitinol, manufactured by Selective Laser Melting, for space applications to reduce vibration between different structural parts in space structures. The powder is NiTi (50.2 at.% of Ni). The structure manufactured by additive technology allows us to eliminate the presence of joint and moving parts and to have a compact solution with high structural strength. The designed dampers had single or double cell structures with three different internal angles (30°, 45° and 60°). This particular shape has damping properties also without the pseudoelastic effect. For this reason, the geometries were reproduced in different materials, SS316L and Ti6Al4V, to test the geometry loss factor. The mechanical performances of these specimens were compared to the ones of NiTi structures, pointing out good damping properties of the designed structure and the highest performances of the NiTi pseudoelastic effect. The NiTi damper was mechanically characterized by static and dynamic tests and with DSC and microscope observations. The experimental results were verified with numerical models and with some scaled steel specimens in which optical fibers were embedded. The realized structure presented good mechanical and damping properties. It was observed that the loss factor and the dissipated energy increased with the angles of the cells.

Keywords: additive manufacturing, damper, nitinol, pseudo elastic effect, selective laser melting, shape memory alloys

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Authors: Michael Wright, Tiago Costa

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The construction industry in SE Asia has been relying on S355 MPa “as rolled” H-beams for many years now. It is an easily sourced, metallurgically simple, reliable product that all designers, fabricators and constructors are familiar with. However, as the Global demand to better use our finite resources gets stronger, the need for an as-rolled S460 MPa H-Beam is becoming more apparent. The Financial benefits of an “as-rolled” S460 MPa H-beam are obvious. The S460 MPa beam which is currently available and used is fabricated from rolled strip. However, making H-beam from 3 x 460 MPa strips requires costly equipment, valuable welding skills & production time, all of which can be in short supply or better used for other purposes. The Metallurgical benefits of an “as-rolled” S460 MPa H-beam are consistency in the product. Fabricated H-beams have inhomogeneous areas where the strips have been welded together - parent metal, heat affected zone and weld metal all in the one body. They also rely heavily on the skill of the welder to guarantee a perfect, defect free weld. If this does not occur, the beam is intrinsically flawed and could lead to failure in service. An as-rolled beam is a relatively homogenous product, with the optimum strength and ductility produced by delivering steel with as fine as possible uniform cross sectional grain size. This is done by cost effective alloy design coupled with proper metallurgical process control implemented into an existing mill’s equipment capability and layout. This paper is designed to highlight the benefits of bring an “as-rolled” S460 MPa H-beam to the construction market place in SE Asia, and hopefully encourage the current “as-rolled” H-beam producers to rise to the challenge and produce an innovative high quality product for the local market.

Keywords: fine grained, As-rolled, long products, process control, metallurgy

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Authors: Gagan Kumar, Koijam M. Devi, Amarendra K. Sarma, Dibakar Roy Chowdhury

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Research in metamaterials has been gaining momentum over the past decade owing to its ability in controlling electromagnetic wave properties through careful design at the sub-wavelength scale. The metamaterials have led to several important phenomena which are useful in a variety of applications. One such phenomenon is the electromagnetically induced transparency (EIT) effect in which a narrow transparency region is created in an otherwise absorptive spectrum. In our work, we explore plasmon induced transparency (PIT) in terahertz metamaterials which is analogues to EIT effect. The PIT effect is achieved using the plasmonic metamaterials in which a unit cell is comprised of two C (2C) shaped resonators and a cut-wire (CW). When terahertz wave of a particular polarization is normally incident on the proposed metamaterials geometry, it strongly couples with the cut wire, resulting in the excitation of the bright mode. However due to the specific polarization of the incident beam, the fundamental modes of the C-shaped resonators are not excited by the incident terahertz, hence they are termed as the dark mode. The PIT effect occurs as a result of interference between the bright and the dark mode. In order to observe PIT effect, both the bright and dark modes should have similar resonant frequencies with a little deviation. We further have examined that the PIT window can be modulated by displacing the C-shaped resonators w.r.t. the cut-wire. The numerical observations for different coupling configurations can be explained through an equivalent lumped element circuit model. Moving ahead the PIT effect is further explored in a metamaterial comprising of a cross like structure and four C-shaped resonators. For such configuration, equally strong PIT effect is observed for two orthogonally polarized lights. Therefore, such metamaterials demonstrate a polarization independent PIT response w.r.t the incident terahertz radiation. The proposed study could be significant in the development of slow light devices and polarization independent sensing applications.

Keywords: terahertz, metamaterial, split ring resonator, plasmon

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Authors: T. P. Yu, J. J. Liu, X. L. Zhu, Y. Yin, W. Q. Wang, J. M. Ouyang, F. Q. Shao

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A strong electromagnetic field with E>1015V/m can be supplied by an intense laser such as ELI and HiPER in the near future. Exposing in such a strong laser field, laser-matter interaction enters into the near quantum electrodynamics (QED) regime and highly non-linear physics may occur during the laser-matter interaction. Recently, the multi-photon Breit-Wheeler (BW) process attracts increasing attention because it is capable to produce abundant positrons and it enhances the positron generation efficiency significantly. Here, we propose an all-optical scheme for bright gamma rays and dense positrons generation by irradiating a 1022 W/cm2 laser pulse onto an Al cone filled with near-critical-density plasmas. Two-dimensional (2D) QED particle-in-cell (PIC) simulations show that, the radiation damping force becomes large enough to compensate for the Lorentz force in the cone, causing radiation-reaction trapping of a dense electron bunch in the laser field. The trapped electrons oscillate in the laser electric field and emits high-energy gamma photons in two ways: (1) nonlinear Compton scattering due to the oscillation of electrons in the laser fields, and (2) Compton backwardscattering resulting from the bunch colliding with the reflected laser by the cone tip. The multi-photon Breit-Wheeler process is thus initiated and abundant electron-positron pairs are generated with a positron density ~1027m-3. The scheme is finally demonstrated by full 3D PIC simulations, which indicate the positron flux is up to 109. This compact gamma ray and positron source may have promising applications in future.

Keywords: BW process, electron-positron pairs, gamma rays emission, ultra-intense laser

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Authors: Chen Jun-Hong, He Pu, Tao Wen-Quan

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Proton exchange membrane fuel cell (PEMFC) is the most promising future energy source owing to its low operating temperature, high energy efficiency, high power density, and environmental friendliness. In this paper, a comprehensive PEMFC system control-oriented model is developed in the Matlab/Simulink environment, which includes the hydrogen supply subsystem, air supply subsystem, and thermal management subsystem. Besides, Improved Artificial Bee Colony (IABC) is used in the parameter identification of PEMFC semi-empirical equations, making the maximum relative error between simulation data and the experimental data less than 0.4%. Operation temperature is essential for PEMFC, both high and low temperatures are disadvantageous. In the thermal management subsystem, water pump and fan are both controlled with the PID controller to maintain the appreciate operation temperature of PEMFC for the requirements of safe and efficient operation. To improve the control effect further, fuzzy control is introduced to optimize the PID controller of the pump, and the Radial Basis Function (RBF) neural network is introduced to optimize the PID controller of the fan. The results demonstrate that Fuzzy-PID and RBF-PID can achieve a better control effect with 22.66% decrease in Integral Absolute Error Criterion (IAE) of T_st (Temperature of PEMFC) and 77.56% decrease in IAE of T_in (Temperature of inlet cooling water) compared with traditional PID. In the end, a novel thermal management structure is proposed, which uses the cooling air passing through the main radiator to continue cooling the secondary radiator. In this thermal management structure, the parasitic power dissipation can be reduced by 69.94%, and the control effect can be improved with a 52.88% decrease in IAE of T_in under the same controller.

Keywords: PEMFC system, parameter identification, temperature control, Fuzzy-PID, RBF-PID, parasitic power

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Authors: N. S. Aggangan, B. Dell, P. Jeffries

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Two moderately nickel-tolerant isolates of Pisolithus were compared with a non-Ni tolerant isolate for the ability to increase the growth of Eucalyptus urophylla seedlings in the presence of nickel (Ni) in pots in a glasshouse. Seedlings, either inoculated with mycorrhizal fungi or uninoculated, were transplanted into pots containing 3 kg steam-pasteurized yellow sand amended with five concentrations of nickel (0, 6, 12, 24 and 48 mg Ni kg-1 soil). Within a day after transplanting, all seedlings subjected to Ni rates greater than 12 mg Ni kg-1 showed symptoms of wilting and all died within two weeks. At lower nickel concentrations, inoculation with all 3 Pisolithus strains increased rates of seedling survival after 12 weeks. Inoculation with all 3 isolates Pisolithus significantly increased the growth of plants in Ni-free soils between 2 to 4 fold dependent on isolate. However, seedlings growing in soils containing 12 mg Ni kg-1 grew poorly, mycorrhizal development was inhibited and no beneficial effects of inoculation were noted. In contrast, in soils containing 6mg Ni kg-1, inoculated seedlings did not show the reduced root growth and severe toxicity symptoms (chlorosis on young leaves and shoot tips) of uninoculated seedlings. Only the Ni-tolerant Pisolithus strains conferred a significant growth benefit compared to non-inoculated controls, and plants inoculated with one of these strains grew twice the size as those inoculated with the other Ni-tolerant strain. Inorganic plant analysis revealed that inoculation increased plant growth through improved P uptake but did not prevent Ni uptake. However, toxicity may have been minimized by dilution due to an increase in plant biomass. The results suggest that only one of the Ni-tolerant strains of Pisolithus has the potential to improve the growth and survival of E. urophylla seedlings in serpentine soils in the Philippines.

Keywords: ectomycorrhizas, Eucalyptus urophylla, nickel tolerance, pisolithus

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Authors: Moustafa Elhamouly, Masayuki Shimada

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The production of competent oocytes is essential for reproductivity in mammals. Maintenance of mitochondrial efficiency is required to supply the ATP necessary for granulosa cell proliferation during the follicular development process. Treatment with Pyrroloquinoline quinone (PQQ) has been reported to increase the number of ovulated oocytes and pups per delivery in mice by maintaining healthy mitochondrial function. This study aimed to elucidate how PQQ maintains mitochondrial function during ovarian follicle growth. To do this, both in vitro and in vivo experiments were performed with granulosa cells from superovulated immature (3-week-old) mice that were pretreated with or without PQQ. The effects of PQQ on beta-oxidation, mitochondrial function, mitophagy, and mitochondrial biogenesis were examined. PQQ increased beta-oxidation-related genes and CPT1 protein content in granulosa cells and this was associated with a decreased phosphorylation of P38 signaling protein. Using the fatty acid oxidation assay on the flux analyzer, PQQ increased the reliance of beta-oxidation on the endogenous fatty acids and was associated with a mild UCP-dependant mitochondrial uncoupling, ATP production, mitophagy, and mitochondrial biogenesis. PQQ also increased the expression of endogenous antioxidant enzymes. Thus, PQQ induced beta-oxidation in growing granulosa cells relying on endogenous fatty acids. And reduced the Reactive oxygen species (ROS) production by inducing a mild mitochondrial uncoupling with keeping high mitochondrial function. Damaged mitochondria were recycled by the induced mitophagy and replaced by the increased mitochondrial biogenesis. Collectively, PQQ may enhance reproductivity by maintaining the efficiency of mitochondria to produce enough ATP required for normal folliculogenesis.

Keywords: granulosa cells, mitochondrial uncoupling, mitophagy, pyrroloquinoline quinone (PQQ), reactive oxygen species (ROS).

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