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11.

In this paper, a graphene-based tunable multi-band terahertz absorber is proposed and numerically investigated. The proposed absorber can achieve perfect absorption within both sharp and ultra-broadband absorption spectra. This wide range of absorption is gathered through a unique combination of periodically cross- and square-shaped dielectrics sandwiched between two graphene sheets; the latter enables it to offer more absorption in comparison with the traditional single-layer graphene structures. The aforementioned top layer is mounted on a gold plate separated by a Topas layer with zero volume loss. Furthermore, in our proposed approach, we investigated the possibility of changing the shapes and sizes of the dielectric layers instead of the geometry of the graphene layers to alleviate the edge effects and manufacturing complications. In numerical simulations, parameters, such as graphene Fermi energy and the dimensions of the proposed dielectric layout, have been optimally tuned to reach perfect absorption. We have verified that the performance of our dielectric layout called fishnet, with two widely investigated dielectric layouts in the literature (namely, cross-shaped and frame-and-square). Our results demonstrate two absorption bands with near-unity absorbance at frequencies of 1.6–2.3 and 4.2–4.9 THz, with absorption efficiency of 98% in 1.96 and 4.62 THz, respectively. Moreover, a broadband absorption in the 7.77–9.78 THz is observed with an absorption efficiency of 99.6% that was attained in 8.44–9.11 THz. Finally, the versatility provided by the tunability of three operation bands of the absorber makes it a great candidate for integration into terahertz optoelectronic devices.

  相似文献   
12.
Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.  相似文献   
13.
Apis mellifera jemenitica incorporates a few perceived subspecies that vary in their natural properties and farming qualities. Mitochondrial COI gene sequence (mtCOI) has not been used before for bee identification in the southwestern region of Saudi Arabia. The aim of this work was to study the morphometry and analyzing the mtCOI of all collected bees. The nucleotide sequence of the mtCOI gene was analyzed. Similarity searches and distances between each obtained DNA and sequences available in GenBank were made. Morphometric analysis revealed close similarities among the studied bees, but these similarities are different from those previously indicated in earlier studies of the same region. Molecular studies revealed that the collected bees are similar to each other and some other sequences found in GenBank, but these bees are a new hybrid or subspecies that are different from those previously reported in the same region, indicating the emergence of a new hybrid.  相似文献   
14.
Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a non-invasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surround-ings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the"Repeated Measures ANOVA",it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object's temperature with only once time experimenting the color temperature.  相似文献   
15.

Background

The exact mechanisms of morphine-induced dependence and withdrawal symptoms remain unclear. In order to identify an agent that can prevent withdrawal syndrome, many studies have been performed. This study was aimed to evaluate the effect of gap junction blockers; carbenoxolone (CBX) or mefloquine (MFQ); on morphine withdrawal symptoms in male rat.Adult male Wistar rats (225 – 275 g) were selected randomly and divided into 10 groups. All groups underwent stereotaxic surgery and in order to induce dependency, morphine was administered subcutaneously) Sc) at an interval of 12 hours for nine continuous days. On the ninth day of the experiment, animals received vehicle or CBX (100, 400, 600 μg/10 μl/rat, icv) or MFQ (50, 100 and 200 μg/10 μl/rat, icv) after the last saline or morphine (Sc) injection. Morphine withdrawal symptoms were precipitated by naloxone hydrochloride 10 min after the treatments. The withdrawal signs including: jumping, rearing, genital grooming, abdomen writhing, wet dog shake and stool weight, were recorded for 60 minutes.

Results

Results showed that CBX and MFQ decreased all withdrawal signs; and the analysis indicated that they could attenuate the total withdrawal scores significantly.

Conclusion

Taking together it is concluded that gap junction blockers prevented naloxone-precipitated withdrawal symptoms.  相似文献   
16.
The properties of Trematosphaeria mangrovei laccase enzyme purified on Sephadex G-100 column were investigated. SDS–PAGE of the purified laccase enzyme showed a single band at 48 kDa. The pure laccase reached its maximal activity at temperature 65 °C, pH 4.0 with Km equal 1.4 mM and Vmax equal 184.84 U/mg protein. The substrate specificity of the purified laccase was greatly influenced by the nature and position of the substituted groups in the phenolic ring. The pure laccase was tested with some metal ions and inhibitors, FeSO4 completely inhibited laccase enzyme and also highly affected by (NaN3) at a concentration of 1 mM. Amino acid composition of the pure enzyme was also determined. Carbohydrate content of purified laccase enzyme was 23% of the enzyme sample. The UV absorption spectra of the purified laccase enzyme showed a single peak at 260–280 nm.  相似文献   
17.
CpG Island Methylator Phenotype (CIMP) is one of the underlying mechanisms in colorectal cancer (CRC). This study aimed to define a methylome signature in CRC through a methylation microarray analysis and a compilation of promising CIMP markers from the literature. Illumina HumanMethylation27 (IHM27) array data was generated and analyzed based on statistical differences in methylation data (1st approach) or based on overall differences in methylation percentages using lower 95% CI (2nd approach). Pyrosequencing was performed for the validation of nine genes. A meta-analysis was used to identify CIMP and non-CIMP markers that were hypermethylated in CRC but did not yet make it to the CIMP genes’ list. Our 1st approach for array data analysis demonstrated the limitations in selecting genes for further validation, highlighting the need for the 2nd bioinformatics approach to adequately select genes with differential aberrant methylation. A more comprehensive list, which included non-CIMP genes, such as APC, EVL, CD109, PTEN, TWIST1, DCC, PTPRD, SFRP1, ICAM5, RASSF1A, EYA4, 30ST2, LAMA1, KCNQ5, ADHEF1, and TFPI2, was established. Array data are useful to categorize and cluster colonic lesions based on their global methylation profiles; however, its usefulness in identifying robust methylation markers is limited and rely on the data analysis method. We have identified 16 non-CIMP-panel genes for which we provide rationale for inclusion in a more comprehensive characterization of CIMP+ CRCs. The identification of a definitive list for methylome specific genes in CRC will contribute to better clinical management of CRC patients.  相似文献   
18.
The Notch signaling pathway controls a large number of processes during animal development and adult homeostasis. One of the conserved post-translational modifications of the Notch receptors is the addition of an O-linked glucose to epidermal growth factor-like (EGF) repeats with a C-X-S-X-(P/A)-C motif by Protein O-glucosyltransferase 1 (POGLUT1; Rumi in Drosophila). Genetic experiments in flies and mice, and in vivo structure-function analysis in flies indicate that O-glucose residues promote Notch signaling. The O-glucose residues on mammalian Notch1 and Notch2 proteins are efficiently extended by the addition of one or two xylose residues through the function of specific mammalian xylosyltransferases. However, the contribution of xylosylation to Notch signaling is not known. Here, we identify the Drosophila enzyme Shams responsible for the addition of xylose to O-glucose on EGF repeats. Surprisingly, loss- and gain-of-function experiments strongly suggest that xylose negatively regulates Notch signaling, opposite to the role played by glucose residues. Mass spectrometric analysis of Drosophila Notch indicates that addition of xylose to O-glucosylated Notch EGF repeats is limited to EGF14–20. A Notch transgene with mutations in the O-glucosylation sites of Notch EGF16–20 recapitulates the shams loss-of-function phenotypes, and suppresses the phenotypes caused by the overexpression of human xylosyltransferases. Antibody staining in animals with decreased Notch xylosylation indicates that xylose residues on EGF16–20 negatively regulate the surface expression of the Notch receptor. Our studies uncover a specific role for xylose in the regulation of the Drosophila Notch signaling, and suggest a previously unrecognized regulatory role for EGF16–20 of Notch.  相似文献   
19.
The ionome is the elemental composition of a living organism, its tissues, cells or cell compartments. The ionomes of roots, stems and leaves of 14 native Brazilian forest species were characterised to examine the relationships between plant and organ ionomes and the phylogenetic and ecological affiliations of species. The null hypothesis that ionomes of Brazilian forest species and their organs do not differ was tested. Concentrations of mineral nutrients in roots, stems and leaves were determined for 14 Brazilian forest species, representing seven angiosperm orders, grown hydroponically in a complete nutrient solution. The 14 species could be differentiated by their ionomes and the partitioning of mineral nutrients between organs. The ionomic differences between the 14 species did not reflect their phylogenetic relationships or successional ecology. Differences between shoot ionomes and root ionomes were greater than differences in the ionome of an organ when compared among genotypes. In conclusion, differences in ionomes of species and their organs reflect a combination of ancient phylogenetic and recent environmental adaptations.  相似文献   
20.
Nasri  Elahe  Shoaei  Parisa  Vakili  Bahareh  Mirhendi  Hossein  Sadeghi  Somayeh  Hajiahmadi  Somayeh  Sadeghi  Alireza  Vaezi  Afsane  Badali  Hamid  Fakhim  Hamed 《Mycopathologia》2020,185(6):1077-1084
Mycopathologia - Although patients with severe immunodeficiency and hematological malignancies has been considered at highest risk for invasive fungal infection, patients with severe pneumonia due...  相似文献   
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