45 research outputs found
Synthesis and metal complexation of chiral 3-mono-or 3, 3-bis-allyl-2-hydroxypyrrolopyrazine-1, 4-diones
A novel synthesis of chiral cyclic hydroxamic acids (4, 6, 8 and 10) related to cyclodipeptides is described. The crucial reduction of the nitro group of the N-nitroacetyl derivatives of (S)-α-amino acid esters is brought about by zinc-aq. ammonium chloride. The FeIII and CuII complexes of one such cyclic hydroxamic acid 10a have been prepared and their DNAse activity investigated
Archaeoparasitological Strategy Based on the Microscopic Examinations of Prehistoric Samples and the Recent Report on the Difference in the Prevalence of Soil Transmitted Helminthic Infections in the Indian Subcontinent
Archaeoparasitology is a study to acquire data concerning the parasite infection of ancient people through the examination of the specimens obtained in the excavation sites. Although this research has achieved many successes worldwide, there has been few noteworthy reports from South Asia countries. In 2011 to 2016, we thus conducted parasite examinations on Indian archaeological specimens (n = 247) collected at excavation sites of Mature Harappan period (4600ā3900 BP) and their contemporary rural Chalcolithic sites. To derive effective strategy of archaeoparasitological works in Indian Subcontinent, our data were analyzed together with previous clinical report on the soil transmitted helminth infection in the Indian Subcontinent. We propose that future paleoparasitological studies in India should be conducted more intensely on ancient specimens from the states of Assam, Bihar, Jammu and Kashmir, Tamil Nadu, Andhra Pradesh and West Bengal etc
Craniofacial reconstruction of the Indus valley civilization individuals found at 4500-year-old Rakhigarhi cemetery
Despite academic eļ¬orts to study the Indus Valley civilization (IVC), there have as yet been no successful attempts to unveil the IVC peopleās craniofacial appearance. We investigated the IVC cemetery area of Rakhigarhi site, which was estimated to be of 2273 Ā± 38 and 2616 Ā± 73Ā years BCE. By craniofacial reconstruction (CFR) procedure using computed tomography (CT) data of two Rakhigarhi skulls (A1 BR02 and A2 BR36), we successfully reconstructed the faces of the IVC individu-als who were buried about 4500Ā years ago. This is the ļ¬rst attempt to unveil scientiļ¬cally accurate representations of IVC peopleās actual facial morphology
Metal complexation and DNA cleavage activities of N-substituted hydroxamic acids
712-715Hydroxamic acid,
RCON(R')OH, is a bidentate oxygen ligand possessing affinity for a variety of
metal ions. The Cu(II) complexes of three N-substituted hydroxamic acids [R=C6H5;
R'=C6H5, 4-CH3 -C6H4 and
R'= C6H5.CH2] have been synthesized and
characterized. Their DNA cleavage activities have been investigated using
plasmid DNA. An oxidative mechanism for DNA cleavage by hydroxy radicals via
abstraction of a H atom from sugar unit has been proposed.</span
Polarity sensing by fluorescent oligonucleotides: first demonstration of sequence-dependent microenvironmental changes in the DNA major groove
DNA duplex recognition by macromolecules (proteins, enzymes) and small molecules (drugs, metal complexes) occurs in the major or minor grooves of DNA via hydrogen bonding and electrostatic or hydrophobic interactions, whose strengths depend on the medium. It is therefore important to understand the local environments of the major/minor grooves of DNA. It is known that small molecules bind in the minor groove that have nonpolar character (Īµ = 22) and are organic-like. By employing fluorescent oligonucleotides, we demonstrated recently that the major groove of DNA is more polar than the minor groove (Īµ = 55) and the DNA double helix has different polarity in its two grooves. Our experimentally measured values were recently validated independently by two theoretical groups, employing calculations by two different methodologies. In this paper, a hitherto unknown property of DNA double helix ĀÆ sequence dependent local polarity or microenvironment - is experimentally demonstrated. This is shown by fluorescence experiments using oligonucleotides containing the modified base 5-amino-dU in place of dT and the polarity varied between Īµ ā 40 and 60, in different sequences. This is the first experimental demonstration of sequence-dependent microenvironmental effects in DNA in solution, although structural effects are well-known by X-ray data. The technique used has a good potential to investigate differing microenvoronmental effects in various secondary structures, DNA polymorphs, and chemically modified DNA and their hybrids
5-amido-(carboxyfluorescein)-2'-dU-oligonucloetides: novel primers for fluorescent detection of PCR amplified DNA
The synthesis of oligonucleotides containing a novel nucleobase fluorescent derivative 5-NH<SUB>2</SUB>-(carboxyfluorescein)-2'-deoxyuridine, in which the chromophore fluorescein is directly linked to nucleobase of 2'dU at C-5 via an amido function is described. The fluorescent oligonucleotides have been used as primers for PCR amplification of Human β-globin gene fragment. Oligonucleotides containing multiple insertions of such fluorophores have potential applications in molecular biotechnology
EffResUNet: Encoder Decoder Architecture for Cloud-Type Segmentation
Clouds play a vital role in Earth’s water cycle and the energy balance of the climate system; understanding them and their composition is crucial in comprehending the Earth–atmosphere system. The dataset “Understanding Clouds from Satellite Images” contains cloud pattern images downloaded from NASA Worldview, captured by the satellites divided into four classes, labeled Fish, Flower, Gravel, and Sugar. Semantic segmentation, also known as semantic labeling, is a fundamental yet complex problem in remote sensing image interpretation of assigning pixel-by-pixel semantic class labels to a given picture. In this study, we propose a novel approach for the semantic segmentation of cloud patterns. We began our study with a simple convolutional neural network-based model. We worked our way up to a complex model consisting of a U-shaped encoder-decoder network, residual blocks, and an attention mechanism for efficient and accurate semantic segmentation. Being an architecture of the first of its kind, the model achieved an IoU score of 0.4239 and a Dice coefficient of 0.5557, both of which are improvements over the previous research conducted in this field
Laser functionalization: An emerging modality to enhance the osseointegration potential of polyetheretherketone as a dental implant material
The unique physical and mechanical attributes of polyetheretherketone (PEEK) have lent significant momentum to the motion that PEEK can be used as a material of choice for dental implants. However, in contrast to titanium or zirconia, PEEK has very limited inherent osteoconductive properties. A wide variety of research has been conducted till date to improve the bioactivity of PEEK surface. Varied methods have been proposed, laser surface treatment of PEEK being one of the promising techniques. Data collection was limited to the last 10 years from 2012 to 2021. Eleven articles were found suitable for this review found in the databases of PubMed and Google Scholar. Considerable alterations have been observed in surface roughness and wettability characteristics of PEEK after laser surface treatment, which improved the osseointegration property of PEEK to be utilized as a dental implant material. The current paper is aimed at reviewing different types of laser applications to the PEEK surfaces and its effect on bone-to-PEEK implant contact