RF MEMS Based Tunable Bowtie Shaped Substrate Integrated Waveguide Filter

A tunable bandpass filter based on a technique that utilizes substrate integrated waveguide (SIW) and double coupling is presented. The SIW based bandpass filter is implemented using a bowtie shaped resonator structure. The bowtie shaped filter exhibits similar performance as found in rectangular and circular shaped SIW based bandpass filters. This concept reduces the circuit foot print of SIW; along with miniaturization high quality factor is maintained by the structure. The design methodology for single-pole triangular resonator structure is presented. Two different inter-resonator couplings of the resonators are incorporated in the design of the two-pole bowtie shaped SIW bandpass filter, and switching between the two couplings using a packaged RF MEMS switch delivers the tunable filter. A tunning of 1 GHz is achieved for two frequency states of 6.3 and 7.3 GHz. The total size of the circuit is 70mm x 36mm x 0.787 mm (LxWxH)

Millimeter-wave liquid crystal polymer based conformal antenna array for 5G applications

This letter presents the design, fabrication, and performance evaluation of a flexible millimeter-wave (mm-wave) antenna array for the fifth generation (5G) wireless networks operating at Ka-band (26.5-40 GHz). The single element antenna is comprised of a coplanar-waveguide-fed rectangular patch tapered at its sides with two vertically oriented slots. The ground is designed with L-shaped stubs to converge the dispersed radiation pattern for improving the directivity and gain. The antenna fabrication is accomplished by two advanced methods of laser-milling and inkjet printing on a thin film of flexible liquid crystal polymer. A novel and time-efficient method for postprinting sintering is also proposed in this letter. The design is extended in a two-element array for the gain enhancement. Measurements have validated that the proposed antenna array exhibits a bandwidth of 26-40 GHz with a peak gain of 11.35 dBi at 35 GHz, and consistent high gain profile of above 9 dBi in the complete Ka-band. These features recommend the proposed antenna array as an efficient solution for integration in future flexible 5G front ends and mm-wave wearable devices

Cytological evidences of pollen abortion in Ornithogalum caudatum Ait

Ornithogalum caudatum Ait exhibits strong physiological adaptability; however, it suffers a serious menace of pollen abortion, as almost no seed is formed in the plants. In the current study, chromosome karyotype of root-tip cells (RTC) during mitosis, and chromosome behavior of pollen mother cells (PMC) during meiosis in O. caudatum were investigated. We recorded 18 euchromosomes with variable number (28~36) of B chromosomes in the somatic cells genome. In leptonema of meiotic prophase I, the synapsis between euchromosomes was normal, but there were several darker granular nodular bodies in the cells, which could be the precursor for B chromosomes. Some of the cells were observed as duplication loop in zygotene, indicating that the PMCs had gone through a chromosome structure variation with duplication, which could reduce the fertility of pollens. Numerous chromosome bridges, fragments and lagged chromosomes were observed in meiosis anaphase I. It reflects that these cells might have undergone paracentric inversion, which is one of the important reasons of pollen abortion. In meiosis anaphase II, the sister chromatids separate unusually forming the triad, which leads to gamete sterility. These findings conclude that pollen abortion in O. caudatum mainly results from the variation in chromosome structure, which could be related to the B chromosomes in somatic cells.Key words: Chromosome structure variation, B chromosome, root-tip cells, pollen mother cells, gamete sterility

A Millimetre-Wave Two-Dimensional 64-Element Array for Large-Scale 5G Antenna Subsystems

This paper presents the comprehensive design and evaluation of a novel large-scale millimetre-wave (mm-wave) two-dimensional (2-D) 64-element antenna array, for operation in the 28-GHz frequency band. The primary objective of this work is to study the feasibility of designing a high-performance array based on liquid-crystal polymer (LCP) substrate for the deployment in the fifth generation (5G) wireless communication networks and infrastructures. The planar 5G array has presented an impedance bandwidth of 400-MHz, with a peak gain of 23.2 dBi at 27.7-GHz. Moreover, the operation of the mm-wave antenna array has been analysed and validated through a set of high-resolution full-wave electromagnetic (EM) simulations, conducted based on the time-domain finite integration technique (FIT). The proposed 28-GHz 2-D antenna array is a high-performance subsystem in order to be potentially employed in the next-generation 5G communications

Low-profile Flexible Perovskite based Millimetre Wave Antenna

This paper presents the potential of perovskite antenna in the millimeter band. New materials have been developed to obtain suitable chemical characteristics to offer several advantages including simple structure, high operating bandwidth, high gain, compact and low-profile antennas in the millimeter range. The performance of antennas fabricated using these materials is analyzed here. Simulated results of the antenna prototype show a wide bandwidth of 26-33 GHz. Moreover, simulation evaluation of peak gain of the antenna is 1.443 dB at 28.8 GHz. Low efficiency of 45% in the range of operation presents as the main drawback of this design. The analysis is further extended to examine the impact of different flexible substrate materials. The thickness of the patch is also examined to optimize the antenna radiation performance

Flexible and Wearable Graphene-based Terahertz Antenna for Body-Centric Applications

This paper presents a graphene-based wearable antenna operating in the terahertz frequency range. Graphene with its highly attractive electronic properties, and modern manufacturing techniques can yield antennas that are not only flexible but efficient and low-profile, suited for terahertz applications. The graphene antenna investigated here has a resonant frequency of 0.647 THz. The performance of the antenna is evaluated on-body and in free space using three layers of human skin. Simulated results show that the proposed antenna has a bandwidth of 20 GHz and offers a radiation efficiency of 96% in free space and 50% on the body, with respective gains of 7.8 dB and 7 dB. The small and flexible structure of the antenna along with excellent impedance matching, high bandwidth, and gain, and good efficiency makes it an appropriate candidate to shortrange wireless communication in the vicinity of the human body

Stress signaling convergence and nutrient crosstalk determine zinc-mediated amelioration against cadmium toxicity in rice

Consumption of rice (Oryza sativa L.) is one of the major pathways for heavy metal bioaccumulation in humans over time. Understanding the molecular responses of rice to heavy metal contamination in agriculture is useful for eco-toxicological assessment of cadmium (Cd) and its interaction with zinc (Zn). In certain crops, the impacts of Cd stress or Zn nutrition on the biophysical chemistry and gene expression have been widely investigated, but their molecular interactions at transcriptomic level, particularly in rice roots, are still elusive. Here, hydroponic investigations were carried out with two rice genotypes (Yinni-801 and Heizhan-43), varying in Cd contents in plant tissues to determine their transcriptomic responses upon Cd15 (15 µM) and Cd15+Zn50 (50 µM) treatments. High throughput RNA-sequencing analysis confirmed that 496 and 2407 DEGs were significantly affected by Cd15 and Cd15+Zn50, respectively, among which 1016 DEGs were commonly induced in both genotypes. Multitude of DEGs fell under the category of protein kinases, such as calmodulin (CaM) and calcineurin B-like protein-interacting protein kinases (CBL), indicating a dynamic shift in hormonal signal transduction and Ca2+ involvement with the onset of treatments. Both genotypes expressed a mutual regulation of transcription factors (TFs) such as WRKY, MYB, NAM, AP2, bHLH and ZFP families under both treatments, whereas genes econding ABC transporters (ABCs), high affinity K+ transporters (HAKs) and Glutathione-S-transferases (GSTs), were highly up-regulated under Cd15+Zn50 in both genotypes. Zinc addition triggered more signaling cascades and detoxification related genes in regulation of immunity along with the suppression of Cd-induced DEGs and restriction of Cd uptake. Conclusively, the effective integration of breeding techniques with candidate genes identified in this study as well as economically and technologically viable methods, such as Zn nutrient management, could pave the way for selecting cultivars with promising agronomic qualities and reduced Cd for sustainable rice production

Use of Nutritional Supplements in Youth with Medicated and Unmedicated Attention-Deficit/Hyperactivity Disorder

Objective: To find out whether use of nutritional supplements (NUS) differs between children and adolescents with attention-deficit/hyperactivity disorder (ADHD; medicated or unmedicated), compared with those without the disorder. Methods: We used cross-sectional data from the population-based I.Family study conducted between 2013 and 2014 in eight European countries. Parents completed questionnaires and participated in interviews, for example, on health and medical history of their child. Data from 5067 children and adolescents aged 5-17 years were included. Exposures were medicated (with ADHD-approved medication) and unmedicated ADHD. The outcome was the use of NUS, measured by use of any or multiple different NUS. Multivariable logistic regression adjusted for sociodemographics and health determinants was used to find ADHD-depending differences. Results: The study sample comprised 4490 children and adolescents without ADHD and 51 medicated and 76 unmedicated subjects with ADHD. Regarding the use of any NUS, no statistically significant differences were found between children and adolescents without ADHD (18%) and those with medicated (18%) or unmedicated ADHD (22%). However, discrepancies appear when considering multiple use of NUS, not reported for any medicated ADHD subject but remarkably often for unmedicated ADHD subjects (13%), resulting in an adjusted odds ratio of 2.6 (95% confidence interval, 1.2-5.6) when compared with those without ADHD (5%). Conclusion: Children and adolescents who were not using medication for treating ADHD potentially took NUS as oral remedies. Given the potential for a delay of indicated treatments and for use of those NUS which have no proven effectiveness, pediatricians should actively explore whether NUS have been used to treat ADHD core symptoms, and families should be informed that the average effect size has to be considered small

Response of Poaceous Weeds in Wheat to Post-Emergence Herbicides

Poaceous weeds are prolific and competitive in winter crops, but they are more insidious in wheat due to their similar morphology and growing requirements. Herbicides are effective and efficient tools of weed management, however, they are vulnerable to resistance, and herbicides with different modes of action might check the dominance of a particular weed flora. The current study was undertaken to see the response of three poaceous weeds viz., Phalaris minor, Avena fatua and Lolium temulentum, to herbicides Isoproturon, Topik (Clodinafop-p) and Puma Super (Fenoxaprop-p). Completely randomized design with two factor treatments (weeds, herbicides) and eight replications was employed. Data were recorded on chlorotic and necrotic effects of herbicides on weeds, and percent mortality at the time interval of 14, 21 and 28 days after the application of herbicides. Dry biomass weight of weeds was recorded at 30 days after the treatments. Results indicated that all the parameters were affected significantly over the period of time. Maximum counts of chlorotic (2.16) and necrotic (2.97) weeds were observed at the 21st day of treatment. The highest mortality (31.1 %) was recorded at 21st day after the application of herbicides. Phalaris minor was the most resistant weed to herbicides showing the lowest mortality (only 17.7 %) compared to other two weeds. Maximum dry weight of weeds was recorded in control while a minimum of 0.456 g dry weight was observed where Topik (Clodinafop-p) was applied. For the effective control of P. minor, A. fatua and L. temulentum weeds in wheat crop, Topik (15 WP) @ 0.37 kg a.i. ha-1 was proved to be the most suitable herbicide applied at 3-4 foliar stage

Relative validity of a food and beverage preference questionnaire to characterize taste phenotypes in children adolescents and adults

To assess the relative validity of our food and beverage preference questionnaire we investigated the association between sweet and fatty taste preference scores (assessed using a food and beverage preference questionnaire) and sweet and fatty food propensity scores (derived from a food frequency questionnaire). In I.Family, a large European multi-country cohort study, 12, 207 participants from Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden, including 5291 adults, 3082 adolescents, and 3834 children, completed a food and beverage preference questionnaire with 63 items. Cumulative preference scores for sweet and fatty taste were calculated from the single item ranking ranging from 1 to 5. The relative consumption frequency of foods classified as sweet and fatty was used to calculate the corresponding consumption propensities, a continuous variable ranging from 0 to 100. We conducted regression analyses to investigate the association between sweet and fatty taste preference scores and sweet and fatty food propensity scores, respectively, separately for adults, adolescents =12 years, and for children <12 years. The overall sweet taste preference score was positively associated with the sweet food consumption propensity score (ß = 2.4, 95% CI: 2.1;2.7) and the fatty taste preference score was positively associated with the fatty food consumption propensity score (ß = 2.0, 95% CI: 1.8;2.2). After stratification for age (children <12 years, adolescents =12 years, and adults), the effect remained significant in all age groups and was strongest in adolescents and adults. We conclude that our food and beverage preference questionnaire is a useful instrument for epidemiological studies on sensory perception and health outcomes and for the characterization of sensory taste phenotypes