Recently there has been a hint of a gamma-ray line at 130 GeV originated from the galactic centre after the analysis of the Fermi-LAT satellite data. Being monochromatic in nature, it rules out the ...possibility of having its astrophysical origin and there has been a speculation that this line could be originated from dark matter annihilation. In this work, we propose a two component dark matter scenario where an extension of the Standard model by an inert Higgs doublet and a gauge singlet scalar concocted with \(\rm {Z_2 \times Z^{\prime}_2}\) symmetry, is considered. We find that our scenario can not only explain the 130 GeV gamma-ray line through dark matter annihilation but also produce the correct dark matter relic density. We have used the Standard Model Higgs mass around 125 GeV as intimated by the LHC data..
A two component model of nonthermal dark matter is formulated to simultaneously explain the Fermi-LAT results indicating a \(\gamma\)-ray excess observed from our Galactic Centre in the 1-3 GeV ...energy range and the detection of an X-ray line at 3.55 keV from extragalactic sources. Two additional Standard Model singlet scalar fields \(S_2\) and \(S_3\) are introduced. These fields couple among themselves and with the Standard Model Higgs doublet \(H\). The interaction terms among the scalar fields, namely \(H\), \(S_2\) and \(S_3\), are constrained by the application of a discrete \(\mathbb{Z}_2\times \mathbb{Z}^\prime_2\) symmetry which breaks softly to a remnant \(\mathbb{Z}^{\prime \prime}_2\) symmetry. This residual discrete symmetry is then spontaneously broken through an MeV order vacuum expectation value \(u\) of the singlet scalar field \(S_3\). The resultant physical scalar spectrum has the Standard Model like Higgs as \(\chi_{{}_{{}_1}}\) with \(M_{\chi_{{}_{{}_1}}}\sim 125\) GeV, a moderately heavy scalar \(\chi_{{}_{{}_2}}\) with \(50 \,\,{\rm GeV} \leq M_{\chi_{{}_{{}_2}}}\leq 80\,\,{\rm GeV}\) and a light \(\chi_{{}_{{}_3}}\) with \(M_{\chi_{{}_{{}_3}}} \sim 7\) keV. There is only tiny mixing between \(\chi_{{}_{{}_1}}\) and \(\chi_{{}_{{}_2}}\) as well as between \(\chi_{{}_{{}_1}}\) and \(\chi_{{}_{{}_3}}\). The lack of importance of domain wall formation in the present scenario from the spontaneous breaking of the discrete symmetry \({\mathbb{Z}_2^{\prime\prime}}\), provided \(u\leq 10\) MeV, is pointed out. We find that our proposed two component dark matter model is able to explain successfully both the above mentioned phenomena \(-\) the Fermi-LAT observed \(\gamma\)-ray excess (from the \(\chi_{{}_{{}_2}} \rightarrow {\rm b} \bar{\rm b}\) decay mode) and the observation of the X-ray line (from the decay channel \(\chi_{{}_{{}_3}}\rightarrow\gamma \gamma\)) by the XMM-Newton observatory.
The proposed GIS anchored technique helps in pointing out criminal hotspot zones. The process of determination of hotspots is carried out by associating rank (an integer value) to each ward/block on ...the digitized map. The process of hooking up rank to a specific region is carried out on the basis of criminal activity at that particular region. The rank computation is executed through regression analysis using ninth‐degree polynomial curve fitting. This polynomial has been figured out by obtaining information regarding criminal activities from seven police stations throughout the state of West Bengal, India (case study areas). This information involves the highest, moderate, and least crime‐prone areas under the jurisdiction of each of these police stations. The proposed work also determines the felicitous locations for carrying out the construction of police stations and beat houses uniformly, in order to control criminal activities, especially in those zones where these immoral activities are spreading at a hasty pace. For this purpose, fuzzy c‐means clustering technique is being incorporated. The proposed technique further proves to be advantageous over a number of GIS‐based applications related to hotspot‐detecting tasks, since it proves to be very much noteworthy in handling the demerits of such GIS‐based applications. Considering the influencing factors like the level of seismic hazards, radon emission, electromagnetic variations, and so on, the proposed work can prove to be utilitarian in flashing out earthquake‐prone areas and similarly by considering the influencing factors like proximity of earthquake, encumbering on rock material, banishment of lateral support, changes in the water sample of rock or soil frame, clogged drainage, and so on. Landslide‐prone areas also could be detected. Apart from the above‐mentioned areas, the method also could be used effectively and efficiently for any similar kind of hotspot detection tasks (such as detecting accident‐prone areas) just by changing the related influencing factors.
Cellular interactions between Leishmania donovani parasites and human B (Daudi) and T (HUT78) cell lines were studied in vitro. Both promastigotes and amastigotes of L. donovani gained entry in ...approximately 60% of these cells. Transmission electron microscopy revealed the existence of intracellular amastigotes in these cell lines after infection with L. donovani. Immunophenotyping by flow cytometry confirmed the lymphocytic lineages of these cell lines. There was no evidence for intracellular replication of L. donovani in T and B cell lines. The number of intracellular amastigotes peaked on second day post-infection then gradually declined in a time-dependent manner in both the cell lines. Intracellular parasites remained more viable and transformation-competent when infection was performed with amastigotes. Attachment to the cell surface but no internalization of parasites was observed when infection was attempted on human amnion cell line WISH. Amastigotes, not the promastigotes of L. donovani induced IL-12 production by both monocyte and B cell lines.
