1,234 research outputs found
Phaneroptera rentzi Divya & Senthilkumar 2020, sp. nov.
No full textPhaneroptera rentzi sp. nov. Fig. 1—a, i, j, o; Fig.2 —A–N, Diagnostic characters: Male ( ♂ ). Body yellowish green. Fastigium vertices scapus wider, apically narrow with obtuse, a fine median sulcus (Fig. 2C), strong pigmentation on the dorsal side of fastigium as well as the entire pronotum (Fig. 2B, D); anterior margin of pronotum flat, posteriorly concave; tegmen surpassing the hind wing, dorsally flat, clear wing venation, cerci of male strongly bent inward behind the sub genital plate (Fig. 2K), apex of cercus strongly acute with short and stout black spine (Fig. 2M and Fig. 1a), subgenital plate strongly bifurcate, incurved (Fig. 2 J and Fig. 1j). Colouration. Yellowish green colour. Female. Unknown. Type Material. Holotype: ♂, Dharmapuri (N 0 12007 ’11.21’’E 077051 ’.01.94’’), Tamilnadu, India. 11 II 2018. Coll. G. Divya and N. Senthilkumar. Deposited in Gass Forest Museum (GFM), Institute of Forest Genetics and Tree Breeding, Coimbatore, Tamilnadu (India). Distribution. Dharmapuri, Tamilnadu, India. Etymology. This species is named in honour of Dr D. C. F. Rentz, Australia. Discussion. The new species is completely differs from P. spinosa, P. myllocerca, P. falcata and P. gracilis on the structure of subgenital plate, supra anal plate, pronotum and fastigium vertices. P. rentzi, sp. nov. is entirely differ from the P. spinosa, P. myllocerca and P. falcata by the shape of cerci and subgenital plate. P. gracilis and P. rentzi, sp. nov. are look-alike however, the subgenital plate is entirely different (Fig. 1j, m). The lateral lobe of pronotum deeper than long, without white band; fairly and smoothly rounded not forming angle with disc, sharp emargination at posterior end of insertion. Subgenital plate bilobate at the apex. Distal lobe of subgenital plate not smoothly rounded but pointed. Apex of the cerci abruptly bent inwards. Stridulatory vein large almost as wide as left tegmen; distal end of file as in Fig. 2 E.Published as part of Divya, Govindaraj & Senthilkumar, Natchiappan, 2020, Contribution to the knowledge of the genus Phaneroptera (Tettigoniidae Phaneropterinae) with a new record from Tamilnadu, India, pp. 425-434 in Zootaxa 4860 (3) on page 426, DOI: 10.11646/zootaxa.4860.3.7, http://zenodo.org/record/441406
Emergence of a common generalized synchronization manifold in network motifs of structurally different time-delay systems
No full textR. Suresh and D. V. Senthilkumar acknowledges the support from SERB-DST Fast Track scheme for Young Scientists. M. Lakshmanan (M. L.) has been supported by the DST, Government of India sponsored IRHPA research project. M. L. has also been supported by a DAE Raja Ramanna Fellowship.Peer reviewe
FIGURE 4. Trignocorypha angustata a–c in A new species of Trigonocorypha (Orthoptera: Tettigoniidae: Phaneropterinae) from Tamilnadu, India
No full textFIGURE 4. Trignocorypha angustata a–c, male; a, adult DV; b, adult LV; c, male genital plate; a–e female; a, adult, DV; b, pronotum DV; c, pronotum LV; d, cercus; e, ovipositor LV. Scale bar: 4 mm (Courtesy: Waheed Ali Panhwar et al., 2014)Published as part of Senthilkumar, Natchiappan & Divya, Govindaraj, 2020, A new species of Trigonocorypha (Orthoptera: Tettigoniidae: Phaneropterinae) from Tamilnadu, India, pp. 189-195 in Zootaxa 4802 (1) on page 193, DOI: 10.11646/zootaxa.4802.1.13, http://zenodo.org/record/390486
Investigating the role of Nef in HIV infection-induced dysregulation of innate immune cell function
No full textNef is an accessory protein of HIV that is associated with promoting HIV pathogenesis through increasing replication and immune evasion. This has been proven through delta Nef mutation studies which caused low viral load and no development of AIDS. However, Nef isn't an easy target for creating a therapeutic drug due to its lack of enzymatic activity. Here we examined HIV expression in its wildtype and delta Nef mutated forms in humanized mice. The BLTS model, which has been a cornerstone in aiding HIV studies, was re-examined here for functionality. This was done using immunohistochemistry (IHC) staining of healthy BLTS spleen tissues to analyze characterize the major human immune cells, especially T and B cells. The model was then infected with WT and delta Nef HIV types to analyze the differences in infectivity. This was detected through IHC which detects proteins and RNAScope which detects RNA genome. Wildtype HIV was found to have a higher viral infectivity and tissue damage within 2 weeks post infection (wpi) whereas delta Nef mutated HIV took nearly two months post infection (mpi) to reach lesser infectivity, viral genome load and almost no structural damage. Here, we also introduce the HSC-humanized mice model which has different transplant origins from the BLTS mice. This model was phenotyped using flow cytometry and assessed for its functionality through T cell stimulation assays, which gave a positive functionality indicating that this model, once further optimized, can be used for HIV studies. Finally, we also determine the tissue resident presence of natural killer (NK) cells and dendritic cells (DCs) in the BLTS spleen and thymus and their localization within the tissue. This will allow us to further study the effect of Nef on the localization of these crucial innate immune cells and determine how innate immunity combined with defective Nef could potentially be used to suppress the viral reservoirs of HIV
Effects of deep cryogenic treatment on mechanical and tribological properties of AISI D3 tool steel
No full textIn this study, the effects of deep cryogenic treatment (DCT) on the mechanical and tribological properties of AISI D3 tool steel were investigated together with a systematic correlation between their hardness and wear resistance. It was found that conventionally heat treated AISI D3 tool steel samples were significantly hardened via an additional DCT, which was attributed to the more retained austenite elimination, more homogenized carbide distribution and more reduction in carbide size in the samples. As a result, the hardened AISI D3 samples exhibited reductions in their friction and wear during rubbing against alumina and 100Cr6 steel balls under different normal loads due to the effectively hindered removal of surface materials. The results clearly showed that the DCT was an effective way to improve the mechanical and tribological properties of the AISI D3 tool steel samples as the tribological performance of the tool steel samples was significantly influenced by their hardness
Ferrocene-quinoxaline Y-shaped chromophores as fascinating second-order NLO building blocks for long lasting highly active SHG polymeric films
No full textThe first example of a Y-shaped ferrocene quinoxaline derivative with a surprisingly high and stable second harmonic generation (SHG) response in composite polymeric films is reported. The interesting quadratic hyperpolarizability values of different substituted Y-shaped chromophores are also investigated in solution by the EFISH technique
BarA-UvrY two-component system regulates virulence of uropathogenic E. coli CFT073.
No full textUropathogenic Escherichia coli (UPEC), a member of extraintestinal pathogenic E. coli, cause ∼80% of community-acquired urinary tract infections (UTI) in humans. UPEC initiates its colonization in epithelial cells lining the urinary tract with a complicated life cycle, replicating and persisting in intracellular and extracellular niches. Consequently, UPEC causes cystitis and more severe form of pyelonephritis. To further understand the virulence characteristics of UPEC, we investigated the roles of BarA-UvrY two-component system (TCS) in regulating UPEC virulence. Our results showed that mutation of BarA-UvrY TCS significantly decreased the virulence of UPEC CFT073, as assessed by mouse urinary tract infection, chicken embryo killing assay, and cytotoxicity assay on human kidney and uroepithelial cell lines. Furthermore, mutation of either barA or uvrY gene reduced the production of hemolysin, lipopolysaccharide (LPS), proinflammatory cytokines (TNF-α and IL-6) and chemokine (IL-8). The virulence phenotype was restored similar to that of wild-type by complementation of either barA or uvrY gene in trans. In addition, we discussed a possible link between the BarA-UvrY TCS and CsrA in positively and negatively controlling virulence in UPEC. Overall, this study provides the evidences for BarA-UvrY TCS regulates the virulence of UPEC CFT073 and may point to mechanisms by which virulence regulations are observed in different ways may control the long-term survival of UPEC in the urinary tract
Entomopathogenic Fungi for the Management of Calopepla leayana on Gmelina arborea
No full textEntomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae were isolated and identified as natural pathogens of Calopepla leayana. Both the species of fungi were effective against the larval and adult stages of C. leayana causing white and green muscardine diseases respectively. It was also found that B. bassiana was more pathogenic to the pest as compared to M. anisopliae. The susceptibility of larvae and adults was negatively associated with the age and positively associated with the fungal spore concentration. In all the stages from I instar to adult, the highest mortality was observed in 10% of 1x109 spores/ml concentration of B. bassiana among 1, 2.5, 5 & 10% of 1x109 spores/ml concentration. It was also reflected in probit analysis that the concentration of spores required to kill fifty percent of the population was ranges from 0.09% to 5.98% of 1x109 spores/ml concentration of B. bassiana and 1.02% to 9.72% of 1x109 spores/ml concentration of M. anisopliae. The larvae of I instar have shown highest mortality, which gradually decreased with the increase in age or decrease in the concentration of fungal spores. Mass production of B. bassiana using different substrates was attempted to harvest ample amount of spores. This study revealed that spore production was directly proportional to the mycelial weight and incubation period. From the seven substrates tested, wheat flour was identified as one of the suitable substrates for the mass production of B. bassiana. A field trial was conducted to test their efficacy under field conditions. 72-93% mortality was observed in field conditions.-----------------------------------------------------------------------------------------------------Division of Bioprospecting, Institute of Forest Genetics and Tree Breeding, Coimbatore-641002, Tamilnadu, India*Corresponding author, Email: [email protected] This Article As: N. Senthilkumar and S. Murugesan. 2010. Entomopathogenic Fungi for the Management of Calopepla leayana on Gmelina arborea. J. Ecobiotechnol. 2(3): 01-0
Enantioselective Total Synthesis of the Fungal Metabolite Blennolide D and the Enantiomers of Blennolide E and F
No full textExperimental realization of strange nonchaotic attractors in a nonlinear series LCR circuit with nonsinusoidal force
No full textWe have identified several prominent routes, namely, fractalization, fractalization followed by intermittency, intermittency and Heagy-Hammel routes, for the birth of strange nonchaotic attractors (SNAs) in a quasiperiodically forced electronic system with nonsinusoidal (square wave) force as one of the quasiperiodic forces [Senthilkumar et al., 2008]. In addition, a new bubbling route has also been identified in this circuit. Although some of these prominent routes have been reported experimentally [Thamilmaran et al., 2006] in a quasiperiodically forced electronic circuit with both the forcings as sinusoidal forces, experimental identification of all these routes is reported here in a quasiperiodically forced electronic circuit with one of the forcings as a nonsinusoidal (square wave) force. The birth of SNAs by these routes are characterized from both the experimental and numerical data by the maximal Lyapunov exponents and their variance, Poincare maps, Fourier amplitude spectra, spectral distribution functions and the distribution of finite-time Lyapunov exponents
- …
