Characterization of early mouse mesenchymal stem/progenitor cells for generating cartilage and study their role in endochondral ossification

Mesenchymal stem/ stromal cells (MSCs) isolated from mice have allowed to address some of the major issues that could not be investigated by using human MSCs. For this thesis, a thorough characterization of a previously described mouse MSC population, namely PαS MSCs (identified by expression of both PDGFRα and Sca1 antigens) was done. Using a developmental approach, the MSC-like cells were also identified in embryonic stages. We identified 4 subpopulations of PαS cells, based on the expression of the CD90 and CD73 markers. The flow-cytometry based analysis revealed different time points of the emergence of the different subpopulations of these cells during ontogeny. Using a Sox9-GFP reporter line, we were able to correlate these changes with the predominant chondrogenic and osteogenic processes during progression of mouse development and endochondral ossification. A developmental paradigm was used to characterize the “stem” like properties of PαS subpopulations in vitro from postnatal day P2, since a significant increase of this population was observed from E18.5 until P2 after birth. The conditions of the in vitro trilineage differentiation and chondrogenic differentiation were refined to achieve better results by mimicking the molecular pathways operating during limb development. Two subsets of PαS cells were discriminated by the expression of CD90 marker (PαS+CD90+ and PαS+CD90- subsets). These subsets were assessed for their in vivo fate by engrafting cartilage templates generated from these cells subcutaneously in nude mice. Strikingly, the cartilage models generated from the PαS+CD90+ subset remodeled completely to undergo endochondral ossification and the resulting bone ossicles were invaded by host-derived bone marrow cells. On the other hand, the cartilage models generated from the PαS+CD90- subset appeared to remodel only partially. No endochondral ossification was observed, but the expression of Sox9 persisted, which pointed to maintenance of chondrogenic potential. As in vivo functions of MSCs may depend on their interaction with HSCs in the stem cell niche, cartilage templates generated from PαS subsets isolated at embryonic day E18.5 were also engrafted. This developmental stage coincides with migration of the first HSCs from fetal liver to the bone marrow. The remodeling of cartilage into bone was reduced and only small bone ossicles formed when cartilage templates from PαS+CD90+ cells were implanted. Thus, this study focuses on extensive characterization of PαS cells to identify new subpopulations and refining the conditions of multilineage differentiation in these subpopulations with a developmental approach. Emergence of these subpopulations during mouse development to contribute towards cartilage and bone lineage was determined by studying in detail their in vivo fates during endochondral ossification

Comparative Study of Seismic Analysis of Building with Light Weight and Conventional Material

In recent decades, the lightweight materials are used in construction instead of conventional material. Lightweight construction is considered to be favourable due to the saving in construction cost and materials. AAC block is a lightweight structural material with excellent acoustic and thermal insulation properties. Due to the use of lightweight material in construction in seismic zone reduce the percentage of damages. In this paper the attempt has been made to carry out the project comparative study of seismic analysis of building with lightweight and conventional material. Structural model of multi storey building (G+3) and analysis is carried out in STAAD-Pro by RSM (Response Spectrum Method). Building using infill AAC (Autoclaved aerated concrete) block and conventional clay brick masonry are designed for the same seismic hazard in accordance with the applicable provisions given in Indian codes. The analytical results of the buildings will be compared. The project is also aimed at getting familiarity with STAAD-Pro.2008

Jet-powered Outflows in Supermassive Black Hole Binary Candidate SDSS J1048+0055

The search and study of close pairs of supermassive black holes (SMBHs) is important in the study of galaxy mergers which can possibly trigger active galactic nucleus (AGN) activity, and in the context of their evolution into the gravitational wave emitting regime. The quasar SDSS~J1048+0055 was identified as a SMBH binary candidate based on the observed double-peaked \OIII$\lambda\lambda$4959,5007 emission lines and two distinct radio components separated by $\sim 20$~pc \citep{2004ApJ...604L..33Z}. To ascertain the binary nature of this source, we analyzed multi-frequency, multi-epoch very long baseline interferometry (VLBI) data to investigate its pc-scale radio properties. The source shows double components with the western feature being brighter than the eastern one. This brighter component has a brightness temperature of $\sim 10^{10}$~K, spectral index of $\alpha = -0.09 \pm 0.09$ (flat) and is indicative of mildly relativistic beaming. In contrast, the faint component has a lower brightness temperature of $\sim 10^{8-9}$~K and steep spectrum. These clues are consistent with a core--jet structure, moreover, the apparent separation speed between the two components is much higher than the expected orbital motion in a binary SMBH. Thus the present study excludes the association of the two VLBI components with the cores of a SMBH binary, although the SMBH binary possibility (e.g., a pair of radio-loud and radio-quiet AGNs) is not fully ruled out. In the single active galactic nucleus (AGN) scenario, the double-peaked optical emission lines can originate from the jet interacting with the narrow-line region as indicated by a change in the jet direction at $\sim$ 140 pc.Comment: Accepted for publication in ApJ. (13 pages, 2 figures, and 2 tables

Incarcerated Grynfelt-Lesshaft's giant lumbar hernia: a case report

A uncommon posterior abdominal wall defect called the Grynfeltt-Lesshaft hernia permits the herniation of retro and intraperitoneal tissues via the upper lumbar triangle. We describe a case of a post-menopausal woman who visited the surgical OPD because of a bulge that was steadily growing in the right lumbar area. She had a history of spinal tuberculosis and underwent computed tomography (CT) guided aspiration of a paravertebral abscess and surgical fixation of vertebrae. During the initial clinical examination, the swelling resembled a large lipoma, but other potential diagnoses considered were an incisional hernia, large lipoma, abscess, or hematoma. Ultrasonography was inconclusive in differentiating due to the large size and limited visibility. Consequently, contrast-enhanced computed tomography (CECT) scans of the abdomen revealed a substantial defect in the right lumbar area with herniation of the small bowel, large bowel, and omental fat. The diagnosis of a right Grynfelt hernia was established, and the patient was referred for surgical repair. Preoperatively, the hernia was classified as a type "A" lumbar hernia, according to Moreno-Egea et al classification. For the diagnosis of lumbar hernia and surgical planning, computed tomography (CT) is the most commonly used imaging modality. It allows for accurate visualization and assessment of the hernia, aiding in both the diagnosis and the planning of the surgical procedure

A cosmic microscope to probe the Universe from Present to Cosmic Dawn - dual-element low-frequency space VLBI observatory

A space-based very long baseline interferometry (VLBI) programme, named as the Cosmic Microscope, is proposed to involve dual VLBI telescopes in the space working together with giant ground-based telescopes (e.g., Square Kilometre Array, FAST, Arecibo) to image the low radio frequency Universe with the purpose of unraveling the compact structure of cosmic constituents including supermassive black holes and binaries, pulsars, astronomical masers and the underlying source, and exoplanets amongst others. The operational frequency bands are 30, 74, 330 and 1670 MHz, supporting broad science areas. The mission plans to launch two 30-m-diameter radio telescopes into 2,000 km x 90,000 km elliptical orbits. The two telescopes can work in flexibly diverse modes: (i) space-ground VLBI. The maximum space-ground baseline length is about 100,000 km; it provides a high-dynamic-range imaging capacity with unprecedented high resolutions at low frequencies (0.4 mas at 1.67 GHz and 20 mas at 30 MHz) enabling studies of exoplanets and supermassive black hole binaries (which emit nanoHz gravitational waves); (ii) space-space single-baseline VLBI. This unique baseline enables the detection of flaring hydroxyl masers, and more precise position measurement of pulsars and radio transients at milli-arcsecond level; (iii) single dish mode, where each telescope can be used to monitor transient bursts and rapidly trigger follow-up VLBI observations. The large space telescope will also contribute in measuring and constraining the total angular power spectrum from the Epoch of Reionization. In short, the Cosmic Microscope offers astronomers the opportunity to conduct novel, frontier science.Comment: Accepted for publication in Chinese Journal of Space Science, 10 pages, 2 figure

Th1 stimulatory proteins of Leishmania donovani: comparative cellular and protective responses of rTriose phosphate isomerase, rProtein disulfide isomerase and rElongation factor-2 in combination with rHSP70 against visceral leishmaniasis

In visceral leishmaniasis, the recovery from the disease is always associated with the generation of Th1-type of cellular responses. Based on this, we have previously identified several Th1-stimulatory proteins of Leishmania donovani -triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and elongation factor-2 (EL-2) etc. including heat shock protein 70 (HSP70) which induced Th1-type of cellular responses in both cured Leishmania patients/hamsters. Since, HSPs, being the logical targets for vaccines aimed at augmenting cellular immunity and can be early targets in the immune response against intracellular pathogens; they could be exploited as vaccine/adjuvant to induce long-term immunity more effectively. Therefore, in this study, we checked whether HSP70 can further enhance the immunogenicity and protective responses of the above said Th1-stimulatory proteins. Since, in most of the studies, immunogenicity of HSP70 of L. donovani was assessed in native condition, herein we generated recombinant HSP70 and tested its potential to stimulate immune responses in lymphocytes of cured Leishmania infected hamsters as well as in the peripheral blood mononuclear cells (PBMCs) of cured patients of VL either individually or in combination with above mentioned recombinant proteins. rLdHSP70 alone elicited strong cellular responses along with remarkable up-regulation of IFN-γ and IL-12 cytokines and extremely lower level of IL-4 and IL-10. Among the various combinations, rLdHSP70 + rLdPDI emerged as superior one augmenting improved cellular responses followed by rLdHSP70 + rLdEL-2. These combinations were further evaluated for its protective potential wherein rLdHSP70 + rLdPDI again conferred utmost protection (∼80%) followed by rLdHSP70 + rLdEL-2 (∼75%) and generated a strong cellular immune response with significant increase in the levels of iNOS transcript as well as IFN-γ and IL-12 cytokines which was further supported by the high level of IgG2 antibody in vaccinated animals. These observations indicated that vaccine(s) based on combination of HSP70 with Th1-stimulatory protein(s) may be a viable proposition against intracellular pathogens

Radio Sources Segmentation and Classification with Deep Learning

Modern large radio continuum surveys have high sensitivity and resolution, and can resolve previously undetected extended and diffuse emissions, which brings great challenges for the detection and morphological classification of extended sources. We present HeTu-v2, a deep learning-based source detector that uses the combined networks of Mask Region-based Convolutional Neural Networks (Mask R-CNN) and a Transformer block to achieve high-quality radio sources segmentation and classification. The sources are classified into 5 categories: Compact or point-like sources (CS), Fanaroff-Riley Type I (FRI), Fanaroff-Riley Type II (FRII), Head-Tail (HT), and Core-Jet (CJ) sources. HeTu-v2 has been trained and validated with the data from the Faint Images of the Radio Sky at Twenty-one centimeters (FIRST). We found that HeTu-v2 has a high accuracy with a mean average precision ($AP_{\rm @50:5:95}$) of 77.8%, which is 15.6 points and 11.3 points higher than that of HeTu-v1 and the original Mask R-CNN respectively. We produced a FIRST morphological catalog (FIRST-HeTu) using HeTu-v2, which contains 835,435 sources and achieves 98.6% of completeness and up to 98.5% of accuracy compared to the latest 2014 data release of the FIRST survey. HeTu-v2 could also be employed for other astronomical tasks like building sky models, associating radio components, and classifying radio galaxies

Radio Observations of Four Active Galactic Nuclei Hosting Intermediate-mass Black Hole Candidates: Studying the Outflow Activity and Evolution

Observational searches for intermediate-mass black holes (IMBHs; 102-106 M ⊙) include relatively isolated dwarf galaxies. For those that host active galactic nuclei (AGNs), the IMBH nature may be discerned through the accretion-jet activity. We present radio observations of four AGN-hosting dwarf galaxies, which potentially harbor IMBHs. Very large array (VLA) observations indicate steep spectra (indices of −0.63 to −1.05) between 1.4 and 9 GHz. However, a comparison with the 9 GHz in-band spectral index shows a steepening for GH047 and GH158 (implying older/relic emission) and flattening for GH106 and GH163 (implying recent activity). Overlapping emission regions in the VLA 1.4 GHz and our very long baseline array (VLBA) 1.5 GHz observations, and possibly symmetric pc-scale extensions, are consistent with recent activity in the latter two. Using the compact VLBA radio luminosity, X-ray luminosity (probing the accretion activity), and the black hole masses, all AGNs are found to lie on the empirical fundamental plane relation. The four AGNs are radio-quiet with relatively higher Eddington ratios (0.04-0.32) and resemble X-ray binaries during spectral state transitions that entail an outflow ejection. Furthermore, the radio to X-ray luminosity ratio log R X of −3.9 to −5.6 in these four sources support the scenarios that include corona mass ejection from the accretion disk and wind activity. The growth to kpc-scales likely proceeds along a similar trajectory to young AGNs and peaked spectrum sources. These complex clues can thus aid in the detection and monitoring of IMBHs in the nearby universe