The Sh2-294 HII region ionized by a single B0V star features several infrared excess sources, a photodissociation region, and also a group of reddened stars at its border. The star formation scenario ...in this region seems to be quite complex. In this paper, we present follow-up results of Sh2-294 HII region at 3.6, 4.5, 5.8, and 8.0 mu m observed with the Spitzer Space Telescope Infrared Array Camera (IRAC), coupled with H-2 (2.12 mu m) observation, to characterize the young population of the region and to understand its star formation history. We identified 36 young stellar object (YSO, Class I, Class II, and Class I/II) candidates using IRAC color-color diagrams. It is found that Class I sources are preferentially located at the outskirts of the HII region and associated with enhanced H-2 emission; none of them are located near the central cluster. Combining the optical to mid-infrared (MIR) photometry of the YSO candidates and using the spectral energy distribution fitting models, we constrained stellar parameters and the evolutionary status of 33 YSO candidates. Most of them are interpreted by the model as low-mass (\textless 4M(circle dot)) YSOs; however, we also detected a massive YSO (similar to 9M(circle dot)) of Class I nature, embedded in a cloud of visual extinction of similar to 24 mag. Present analysis suggests that the Class I sources are indeed a younger population of the region relative to Class II sources (age similar to 4.5 x 10(6) yr). We suggest that the majority of the Class I sources, including the massive YSOs, are second-generation stars of the region whose formation is possibly induced by the expansion of the HII region powered by a similar to 4 x 10(6) yr B0 main-sequence star.
Combination of natural polymer and nanoparticle has always been fascinating for biomedical applications. Here, we have demonstrated a simplified dessolvation-coprecipitation technique for the ...development of gelatin grafted Fe3O4 magnetic nanoparticles (Gel-MNPs), and investigated their potential applications in drug delivery and hyperthermia therapy. XRD, TEM, FTIR, TGA and light scattering techniques were used to confirm the phase formation of core Fe3O4 MNPs and their successful surface modification with gelatin moieties. The Gel-MNPs showed good aqueous colloidal stability and pH dependent surface charge characteristics. The hydrophobic anticancer agent, curcumin was employed as a model drug to investigate the loading and release properties of Gel-MNPs. A loading efficiency of about 95% was achieved at drug to particle ratio of 1:10 and curcumin loaded Gel-MNPs (Cur-Gel-MNPs) exhibited pH dependent release behaviour of loaded drug with higher release at mild acidic environment. These Cur-Gel-MNPs have shown dose dependent cytotoxicity towards lung (A549) and breast (MCF-7) cancer cell lines. Further, CUR-Gel-MNPs exhibited enhanced heat activated killing of cancer cells under AC magnetic field, suggesting their usefulness for magnetic hyperthermia therapy.
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•Development of curcumin nanoformulation for cancer therapy.•Grafting of gelatin provides hydrophilicity and tunable surface charge property.•Curcumin encapsulation by hydrophobic interaction and their pH dependent release.•Formulation showed dose dependent cytotoxicity towards cancer cells.•Enhanced heat activated killing of cancer cells under AC magnetic field.
Ceropegia odorata Nimmo ex J. Graham (Apocynaceae: Asclepiadoideae) a Critically Endangered plant species from India was recorded in Gujarat after about 45 years in Vijaynagar forest of Sabarkantha ...District (northern Gujarat). It was first collected from Pavagadh in central Gujarat. Long-term conservation and participatory approaches, details on macro- and micro-habitats, associated species, landscape level monitoring programs are suggested for the new recorded locality and hill ranges.
Mechanical tests were performed on a powder-metallurgically processed 7093/SiC/15p discontinuously reinforced aluminum (DRA) composite in different heat-treatment conditions, to determine the ...influence of matrix characteristics on the composite response. The work-hardening exponent and the strain to failure varied inversely to the strength, similar to monolithic Al alloys, and this dependence was independent of the dominant damage mode. The damage consisted of SiC particle cracks, interface and near-interface debonds, and matrix rupture inside intense slip bands. Fracture surfaces revealed particle fracture-dominated damage for most of the heat-treatment conditions, including an overaged (OA) condition that exhibited a combination of precipitates at the interface and a precipitate-free zone (PFZ) in the immediate vicinity. In the highly OA conditions and in a 450°C as-rolled condition, when the composite strength became less than 400 MPa, near-interface matrix rupture became dominant. A combination of a relatively weak matrix and a weak zone around the particle likely contributed to this damage mode over that of particle fracture. Fracture-toughness tests show that it is important to maintain a proper geometry and testing procedure to obtain valid fracture-toughness data. Overaged microstructures did reveal a recovery of fracture toughness as compared to the peak-aged (PA) condition, unlike the lack of toughness recovery reported earlier for a similar 7XXX (Al-Zn-Cu-Mg)—based DRA. The PA material exhibited extensive localization of damage and plasticity. The low toughness of the DRA in this PA condition is explored in detail, using fractography and metallography. The damage and fracture micromechanisms formed the basis for modeling the strength, elongation, toughness, and damage, which are described in Part II of this work.
Spinal and bulbar muscular atrophy is caused by polyglutamine (polyQ) expansions in androgen receptor (AR), generating gain-of-function toxicity that may involve phosphorylation. Using cellular and ...animal models, we investigated what kinases and phosphatases target polyQ-expanded AR, whether polyQ expansions modify AR phosphorylation, and how this contributes to neurodegeneration. Mass spectrometry showed that polyQ expansions preserve native phosphorylation and increase phosphorylation at conserved sites controlling AR stability and transactivation. In small-molecule screening, we identified that CDC25/CDK2 signaling could enhance AR phosphorylation, and the calcium-sensitive phosphatase calcineurin had opposite effects. Pharmacologic and genetic manipulation of these kinases and phosphatases modified polyQ-expanded AR function and toxicity in cells, flies, and mice. Ablation of CDK2 reduced AR phosphorylation in the brainstem and restored expression of
and other genes involved in DNA damage, senescence, and apoptosis, indicating that the cell cycle-regulated kinase plays more than a bystander role in SBMA-vulnerable postmitotic cells.
Pseudomonas flourescens NCIM 2100 was obtained from NCL, Pune, India, that was adapted to growth on 4 amino 1-1 azo benzene 3,4-Disulfonic acid. This strains was tested by UV,
1H NMR, and IR ...spectroscopy for its ability to degrade the dye which resulted in to sulfonated analogs namely p-amino benzene sulfonic acid sodium salt and 2,4 diamino benzene sulfonic acid sodium salt. These compound further changed to either 2,4 dihydroxy benzene sulfonic acid sodium salt or 2 amino 4 hydroxy benzene sulfonic acid sodium salt, or 4 amino 2 hydroxy benzene sulfonic acid sodium salt. These breakdown compounds were non toxic in nature.
Binding of a solvated peptide A1 ((1)E (2)P (3)L (4)Q (5)L (6)K (7)M) with a graphene sheet is studied by a coarse-grained computer simulation involving input from three independent simulated ...interaction potentials in hierarchy. A number of local and global physical quantities such as energy, mobility, and binding profiles and radius of gyration of peptides are examined as a function of temperature (T). Quantitative differences (e.g., the extent of binding within a temperature range) and qualitative similarities are observed in results from three simulated potentials. Differences in variations of both local and global physical quantities suggest a need for such analysis with multiple inputs in assessing the reliability of both quantitative and qualitative observations. While all three potentials indicate binding at low T and unbinding at high T, the extent of binding of peptide with the temperature differs. Unlike un-solvated peptides (with little variation in binding among residues), solvation accentuates the differences in residue binding. As a result the binding of solvated peptide at low temperatures is found to be anchored by three residues, (1)E, (4)Q, and (6)K (different from that with the un-solvated peptide). Binding to unbinding transition can be described by the variation of the transverse (with respect to graphene sheet) component of the radius of gyration of the peptide (a potential order parameter) as a function of temperature.
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