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A modified microstrip patch antenna is implemented on Polyethylene terephthalate (PET) substrate with a thickness of 0.125 mm for 5G applications. The wideband antenna of 60 ×75 mm2 total dimensions is fabricated using novel inkjet printer and silver nano-particles as the conductive ink. The designed and fabricated antenna operates within 7 to 13 GHz and exhibits almost omnidirectional radiation pattern with an average gain of 5 dBi. The flexible antenna was also tested under bending conditions and showed good performance within the X-band region. The originality of the work lies in the combination of the antenna's structure, flexibility, and targeted frequency of operation. [ABSTRACT FROM AUTHOR]

In this letter, a semi-transparent frequency reconfigurable antenna is proposed and investigated. This antenna is implemented on glass as a substrate, AgHT-4 as a radiating element and copper as its ground plane to result in a semi-transparent feature. A pair of PIN diodes is utilized as microwave switches along with a DC biasing circuit. This proposed antenna is fed by a CPW arrangement and introduces unequal E-shaped Defected Ground Structure (DGS) on the ground plane for modification of the electrical length. The antenna exhibits a −10 dB impedance bandwidth from 3 to 6 GHz when PIN diodes are ON, and a resonance at 4.75 GHz when pin diodes are OFF. The proposed antenna is fabricated to validate its performance in terms of reflection coefficient and radiation pattern. [ABSTRACT FROM AUTHOR]

This letter presents the design of a flexible branch-line coupler (BLC) using a rubber conductor (Zoflex) as the conductive element and polydimethylsiloxane (PDMS) as a substrate. The BLC is meant to operate at 6 GHz operating frequency. The use of PDMS material as a substrate for the BLC design adds a special characteristic of the PDMS on this passive microwave device. The PDMS has some unique properties such as transparency, durability, and lightweight. Moreover, its high electrical resistivity of 2.9 × 1014 Ω m and moderate dielectric constant of 2.7 make the PDMS a good substrate material for flexible devices. This desirable property gives the proposed device full range of flexibility and a great advantage in terms of durability without degrading the performance of the BLC. From the results obtained for bending and non-bending conditions, it can be seen that within the frequency range of operation, both the return loss and the isolation are kept below the theoretical value of −10 dB. The slight difference observed in the simulated and measured FBWs is due the fabrication tolerances. [ABSTRACT FROM AUTHOR]

This article presents the design and implementation of a Miniaturized 3 dB hybrid coupler with low-cost instant inkjet printing technology. The coupler has a promising potential advantage in applications in antenna beam forming network and feeding networks for phased antenna array. Explicit design equations were derived and used in the design of the coupler. To validate the design procedure, a prototype of the 3-dB coupler was implemented using the low-cost instant inkjet silver-nano printing technology. The responses of the hybrid show that the return loss and isolation are both below −20 dB at the designed frequency. The size reduction of this coupler is 73.7%. However, there is little drop in the bandwidth from that of the conventional coupler. This bandwidth reduction is a payback for the significant size reduction. [ABSTRACT FROM AUTHOR]

A flexible microstrip grid array antenna (MGAA) fabricated by printing the patch and the ground plane using a 0.25 -mm -thick conductive rubber layer onto a 1.9 mm thick Polydimethylsiloxane (PDMS) substrate layer is presented in this article. The proposed antenna was designed to operate at 14 GHz frequency band. It is composed of 24 radiating elements to achieve a high gain and compact size characteristics. The measurement results shows that the antenna exhibits wideband characteristics in return loss ( S11) covered from 12 to 18 GHz and it can works at bending state without sacrificing the performance. The measured radiation pattern results also present good agreement with the simulated results. All the criteria of this proposed antenna make it as a suitable candidate to be applied for future flexible and conformal-5G mobile communication applications. [ABSTRACT FROM AUTHOR]

ABSTRACT A miniaturized dual band Microstrip Slot antenna operating at 2.45 GHz and 5.8 GHz is presented. The antenna element consists of a microstrip line-fed metal patch with various slots on the patch resonator. To realize dual band characteristics, a pair of mirror-image L-shaped slots and a pair of slits on the patch resonator are utilized. The square slot in the middle of the patch is etched to enable more compactness, with a 41.2% area reduction as compared to a conventional square patch antenna. The measurement results demonstrate that the proposed antenna provides acceptable radiation performances with directional radiation patterns at desired frequencies. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1358-1362, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT A CPW-fed frequency reconfigurable dielectric resonator antenna (DRA) is studied and presented for WiMAX and wireless local area network applications. The frequency tunable DRA is able to alter the frequency at three different dual bands frequency. The rectangular dielectric resonator has a permittivity of 10. Two PIN diode switches are located on the connecting lines of the network, which feeds the three dielectric resonator elements. Three dual-band modes with center frequency of 2.4 and 5 GHz in ON-ON state, 2.5 and 5.2 GHz in OFF-ON state, 3.5 and 5.8 GHz in ON-OFF state by switching of the diodes are achieved. The proposed dielectric resonator (DR) antenna has a compact size of 33 × 45 mm2 with a DR thickness of 2.8 mm. the simulation and measurement results are compared to prove the good agreement and performance of the proposed antenna. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:579-582, 2015 [ABSTRACT FROM AUTHOR]

A design of a 3-dB ultra wideband (UWB) coupler with compact size (35 mm × 15 mm), which operates between 3.1 and 10.6 GHz is presented in this article. The proposed design is accomplished by using multilayer microstrip structure, which is formed by three layers of conductor and two layers of substrate. The top and bottom layers consist of an octagon-shaped microstrip lines and an octagon-shaped slot in the middle layer. The design was fabricated on Rogers RO4003c substrate. Both of the simulation and measurement results are being compared with verify the coupler's performances in real environment. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:127-130, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27259 [ABSTRACT FROM AUTHOR]

Liquid phase functionalisation of carbon nanotubes is carried out via a H2SO4 + HNO3 mixture, and the effect of the sulphuric to nitric acid volume ratio (1:3-3:1) is systematically investigated by means of complementary techniques, observing the expected progressive downgrade of the crystalline quality, along with the increase of oxygenated functionality concentration. In addition, in contrast with common expectations, the results obtained demonstrate that the concentration of carboxylic groups (acids and anhydrides) never exceeds that of all other functionalities (lactones, phenols, quinones/carbonyls and sulphonic groups) introduced by chemical oxidation. Only by using equal volumes of sulphuric and nitric acids the concentrations of carboxylic and non-carboxylic groups become comparable. Raman analysis reveals that a change in the sample homogeneity accompanies the variations of the relative proportions of the various oxygenated groups, by the typology of which the vibration modes of carbon pairs and carbon rings appear to be affected to different extents. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

. Inhibitors are a serious complication, considerably increasing the morbidity, mortality and cost of treatment in this patient group [1]. The challenge of treating people with haemophilia (PWH) with inhibitors can be met by a well-coordinated multidisciplinary team specialized in haemophilia. Each treatment centre must run a screening programme to detect inhibitors within their population and develop protocols to treat these patients. The treatment centre in Buenos Aires developed a screening programme that tests all our patients twice a year, ensuring early detection of inhibitors and early treatment of complications. In 2006, we analysed the quality of life (QOL) of non-inhibitor patients and compared it with inhibitor patients detected by this programme and found no differences in QOL measured by the SF36 questionnaire and no differences in school absenteeism [2]. When diagnosis of the inhibitor does not come from a screening programme, its presence is suspected upon a lack of response to conventional replacement therapy for musculoskeletal bleeding, losing the 'golden moment' of treatment. This complication is much more serious when facing a traumatic bleed. In this situation, the lack of early diagnosis can lead to permanent damage or even death. Due to the cost of bypassing factors and the lack of experience of the medical team in the treatment of patients with inhibitors, many treatments that would improve the QOL of patients are instituted in an insufficient manner. Therefore, patients with haemophilia and inhibitors are often untreated or undertreated in their community. Orthopaedic surgeons and physiotherapists play a key role in the treatment of these patients and should be included in therapeutic decision making and most specifically in the postoperative treatment of patients with haemophilia and inhibitors. It is important that these patients have quick access to a trained therapeutic team in order to obtain an early diagnosis and treatment plan to prevent the evolution of the pathological process. Early treatment is cost-effective in maintaining and improving the QOL of patients. Experience in patients with haemophilia and inhibitors is not very extensive. Today, this situation is changing, with several treatment centres beginning to perform surgeries in these most complex patients, giving them a chance to improve their QOL. This article presents the experience of experts from various fields involved in treating patients with inhibitors from a developed and developing world perspective. [ABSTRACT FROM AUTHOR]

Poly(butylene succinate) (PBS) filled kenaf bast fiber (KBF) composites were fabricated via compression molding. The effects of KBF loading on the flexural and impact properties of the composites were investigated for fiber loadings of 10-40 wt %. The optimum flexural strength of the composites was achieved at 30 wt % fiber loading. However, the flexural modulus of the composites kept increasing with increasing fiber loading. Increasing the fiber loading led to a drop in the impact strength of about 57.5-73.6%; this was due to the stiff nature of the KBF. The effect of the fiber length (5, 10, 15, and 20 mm) on the flexural and impact properties was investigated for the 30 wt % KBF loaded composites. The composites with 10-mm KBF showed the highest flexural and impact properties in comparison to the others. The inferior flexural and impact strength of the composites with 15- and 20-mm KBF could be attributed to the relatively longer fibers that underwent fiber attrition during compounding, which consequently led to the deterioration of the fiber. This was proven by analyses of the fiber length, diameter, and aspect ratio. The addition of maleated PBS as a compatibilizer resulted in the enhancement of the composite's flexural and impact properties due to the formation of better fiber-matrix interfacial adhesion. This was proven by scanning electron microscopy observations of the composites' fracture surfaces. The removal of unreacted maleic anhydride and dicumyl peroxide residuals from the compatibilizers led to better fiber-matrix interfacial adhesion and a slightly enhanced composite strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Abstract: Articular cartilage extracellular matrix (ECM) plays a crucial role in regulating chondrocyte functions via cell–matrix interaction, cytoskeletal organization and integrin-mediated signaling. Factors such as interleukins, basic fibroblast growth factor (bFGF), bone morphogenic proteins (BMPs) and insulin-like growth factor (IGF) have been shown to modulate the synthesis of extracellular matrix in vitro. However, the effects of TGF-β1 and β-estradiol in ECM regulation require further investigation, although there have been suggestions that these factors do play a positive role. To establish the role of these factors on chondrocytes derived from articular joints, a study was conducted to investigate the effects of TGF-β1 and β-estradiol on glycosaminoglycan secretion and type II collagen distribution (two major component of cartilage ECM in vivo). Thus, chondrocyte cultures initiated from rabbit articular cartilage were treated with 10ng/ml of TGF-β1, 10nM of β-estradiol or with a combination of both factors. Sulphated glycosaminoglycan (GAG) and type II collagen levels were then measured in both these culture systems. The results revealed that the synthesis of GAG and type II collagen was shown to be enhanced in the TGF-β1 treated cultures. This increase was also noted when TGF-β1 and β-estradiol were both used as culture supplements. However, β-estradiol alone did not appear to affect GAG or type II collagen deposition. There was also no difference between the amount of collagen type II and GAG being expressed when chondrocyte cultures were treated with TGF-β1 when compared with cultures treated with combined factors. From this, we conclude that although TGF-β1 appears to stimulate chondrocyte ECM synthesis, β-estradiol fails to produce similar effects. The findings of this study confirm that contrary to previous claims, β-estradiol has little or no effect on chondrocyte ECM synthesis. Furthermore, the use of TGF-β1 may be useful in future studies looking into biological mechanisms by which ECM synthesis in chondrocyte cultures can be augmented, particularly for clinical application. [Copyright &y& Elsevier]

A fluorometric microplate assay was performed for the detection of respiratory burst activity in a human leukaemia cell line HL-60 by assessing oxidation of 2',7'-dichlorofluorescin diacetate (DCFH-DA). This method is based on the detection of DCFH oxidation due to the presence of hydrogen peroxide. In the present study, the antioxidant activity of a number of structurally related flavonoids of plant origin and some of their microbial transformation products (1–18) were evaluated. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new geometry of compact wideband/dual-band circularly polarised dielectric resonator antenna (DRA) is presented. First, a wideband DRA is realised by a rectangular dielectric resonator excited by a vertical coaxial probe feed which is supported by a small substrate. Circular polarisation is achieved by utilising a configuration of the DRA feed that excites orthogonal modes inside the DRA. A 3 dB axial-ratio bandwidth of about 20.8% (9.05-11.14 GHz) is achieved. Second, extension to dual-band circularly polarised operation is then realised by additionally removing a corner of the rectangular DRA at 45° and adding a floating parasitic strip. The experimental results demonstrate an impedance bandwidth of about 59.8% (6.57- 12.18 GHz) and the dual 3 dB axial-ratio bandwidths of about 10.6% (8.31-9.24 GHz) and 13.5% (10.18-11.66 GHz). The measured peak gain varies from 4.47 to 4.86 dBiC in the lower band and 4.33 to 4.91 dBiC in the upper band. [ABSTRACT FROM AUTHOR]

Sorption kinetics of pollutant oils, such as kerosene, virgin naphtha, crude oil, and pump oil, into porous siloxanic foams filled with carbon nanotubes (CNTs) are investigated. Both, pristine and functionalized, CNTs are used as foam fillers. Among all, the foam filled with pristine CNT shows a poor affinity with water and high sorption rate in light oils, in which it achieves the highest absorption values (7991 mg g−1 after 660 s and 6685 mg g−1 after 420 s, respectively, in virgin naphtha and kerosene). The kinetic data are described by the pseudo‐first order, pseudo‐second order, Elovich and intraparticle diffusion models. Results show that chemisorption processes are rate limiting the sorption step. In fact, pseudo‐second order model better represents the equilibrium isotherm data. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47374. [ABSTRACT FROM AUTHOR]

This Letter describes a simple compensation method to reduce the transfer efficiency variation in a resonant inductive coupling (RIC) wireless power transfer link subject to lateral misalignment. The technique is based on impedance matching an RIC link such that the link operates at either over-coupling or critical coupling within the extents of lateral misalignment. Applying the method in a test scenario led to a reduction in the range of obtained transfer efficiency values, from 45% of peak value in a conventional arrangement, to 5%. The proposed method has a potential for application in the design of free-positioning planar wireless chargers. [ABSTRACT FROM AUTHOR]

In the title mol­ecule, C14H9N3O3Cl2S, the dihedral angles between the mean plane of the central carbonyl­thio­urea group, N2CSCO, and the mean planes of the 3-nitro­benzoyl and 3,4-dichloro­phenyl groups are 22.82 (9) and 69.75 (11)°, respectively. The crystal packing is stabilized by weak inter­molecular C—H⋯O hydrogen bonds, forming a one-dimensional chain along the b axis. [ABSTRACT FROM AUTHOR]

In the title mol­ecule, C14H9ClN4O5S, all bond lengths and angles show normal values. The mean plane of the central thio­urea unit, N2CS, makes dihedral angles of 9.54 (12) and 56.60 (10)°, respectively, with the mean planes of the 3-nitro­benzoyl and 4-chloro-3-nitro­phenyl groups. The crystal packing is stabilized by weak inter­molecular N—H⋯O and C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Aims: At first-episode psychosis (FEP), many patients will be routed within familial networks and supported by informal carers who are predominately close family members such as parents. Carer burden, distress and poorer coping styles are associated with different illness beliefs. The current study sought to examine the impact and acceptability of a 3 session, cognitively informed, group intervention targeting illness beliefs previously linked to distress and poorer caregiving experiences in FEP carers., Methods: Carers attending a routine FEP service were invited to attend the group intervention and completed a measure of illness beliefs at baseline and post intervention., Results: Data on 68 carers with complete datasets are presented. Carers were predominately females (64.2%). Group attendance was linked to positive improvements in carer baseline beliefs about the negative consequences of the illness for the patient and themselves, attributions of blame about the illness to the patient and themselves and their overall understanding about the illness. Significant improvements in their understanding of the illness timeline and course, and confidence in dealing with difficulties were also identified., Conclusions: A cognitively informed group approach to targeting the less adaptive illness beliefs reported by FEP carers may offer an effective and acceptable pathway to facilitate their understanding of the illness and adjustment. Further studies using controlled designs are required., (© 2017 John Wiley & Sons Australia, Ltd.)

In hepatocytes, ursodeoxycholic acid (UDCA) activates cell signalling pathways such as p53, intracellular calcium ([Ca 2+ ] i ), and sphingosine-1-phosphate (S1P)-receptor via Gα i -coupled-receptor. Recently, UDCA has been shown to protect the heart against hypoxia-reoxygenation injury. However, it is not clear whether UDCA cardioprotection against hypoxia acts through a transcriptional mediator of cells stress, HIF-1α and p53. Therefore, in here, we aimed to investigate whether UDCA could protect cardiomyocytes (CMs) against hypoxia by regulating expression of HIF-1α, p53, [Ca 2+ ] i , and S1P-Gα i -coupled-receptor. Cardiomyocytes were isolated from newborn rats (0-2 days), and hypoxia was induced by using cobalt chloride (CoCl 2 ). Cardiomyocytes were treated with UDCA and cotreated with either FTY720 (S1P-receptor agonist) or pertussis toxin (PTX; Gα i inhibitor). Cells were subjected for proliferation assay, beating frequency, QuantiGene Plex assay, western blot, immunofluorescence, and calcium imaging. Our findings showed that UDCA counteracted the effects of CoCl 2 on cell viability, beating frequency, HIF-1α, and p53 protein expression. We found that these cardioprotection effects of UDCA were similar to FTY720, S1P agonist. Furthermore, we observed that UDCA protects CMs against CoCl 2 -induced [Ca 2+ ] i dynamic alteration. Pharmacological inhibition of the Gα i -sensitive receptor did not abolish the cardioprotection of UDCA against CoCl 2 detrimental effects, except for cell viability and [Ca 2+ ] i . Pertussis toxin is partially effective in inhibiting UDCA protection against CoCl 2 effects on CM cell viability. Interestingly, PTX fully inhibits UDCA cardioprotection on CoCl 2 -induced [Ca 2+ ] i dynamic changes. We conclude that UDCA cardioprotection against CoCl 2 -induced hypoxia is similar to FTY720, and its actions are not fully mediated by the Gα i -coupled protein sensitive pathways. Ursodeoxycholic acid is the most hydrophilic bile acid and is currently used to treat liver diseases. Recently, UDCA is shown to have a cardioprotection effects; however, the mechanism of UDCA cardioprotection is still poorly understood. The current data generated were the first to show that UDCA is able to inhibit the activation of HIF-1α and p53 protein during CoCl 2 -induced hypoxia in cardiomyocytes. This study provides an insight of UDCA mechanism in protecting cardiomyocytes against hypoxia., (Copyright © 2017 John Wiley & Sons, Ltd.)