171 research outputs found
Secretory carcinoma of the breast, commonly exhibits the features of low grade, triple negative breast carcinoma- A Case report with updated review of literature
Secretory carcinoma of the breast (SBC) is a rare breast neoplasm. Most of the patients present at an early stage with a relatively indolent clinical course. Lymph node and distant metastasis are also very infrequent. The histomorphological features of the secretory breast carcinoma are quite characteristic. Predominantly three histological patterns, solid, microcystic, and tubular, have been noted with copious amounts of intra and extracellular secretory material. Most commonly, no positivity for estrogen receptor (ER), progesterone receptor (PR) and ERBB2(HER2/neu) is observed in SBCs. As SBC can occasionally be hormone receptor-positive, they should not be categorized in the triple-negative breast carcinoma (TNBC) group in general. A very characteristic genetic translocation t (12;15) has been noted in this rare tumor, resulting in a fusion between ETV6 and NTRK3 proteins. We present a case of a 60-year-old lady who presented with right breast lump of 1-month duration and was managed by lumpectomy and sentinel lymph node dissection. Axillary dissection was not performed because the sentinel lymph node biopsy was negative. Postoperative radiotherapy was given to the right breast with a boost to the tumor bed. No adjuvant chemotherapy was given No recurrence has been noted even after a year of the completion of treatmen
Mueller matrix polarimetry of plasmon resonant silver nano-rods: biomedical prospects
Fundamental understanding of the light-matter interaction in the context of
nano-particles is immensely bene- fited by the study of geometry dependent
tunable Localized Surface Plasmon Resonance (LSPR) and has been demonstrated to
have potential applications in various areas of science. The polarization
characteristics of LSPR in addition to spectroscopic tuning can be suitably
exploited in such systems as contrast enhancement mech- anisms and control
parameters. Such polarization characteristics like diattenuation and retardance
have been studied here using a novel combination of Muller-matrix polarimetry
with the T-matrix matrix approach for silver nano-rods to show unprecedented
control and sensitivity to local refractive index variations. The study carried
out over various aspect ratios for a constant equal volume sphere radius shows
the presence of longitu- dinal (dipolar and quadrupolar) and transverse
(dipolar) resonances; arising due to differential contribution of
polarizabilities in two directions. The overlap regions of these resonances and
the resonances themselves exhibit enhanced retardance and diattenuation
respectively. The spectral and amplitude tunability of these polarimetric
parameters through the aspect ratios to span from the minimum to maximum ([0,
1] in the case of diattenuation and [0, {\pi}] in the case of retardance)
presents a novel result that could be used to tailor systems for study of
biological media. On the other hand, the high sensitivity of diattenuation dip
(caused by equal contribution of polarizabilities) could be possibly used for
medium characterization and bio-sensing or bio-imaging studies.Comment: 8 pages, 6 figures, Proceedings of the Saratov Fall Meeting, 201
What does a manager focus on? : a system dynamics based analysis
Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 101-102).Multisourcing has its own set of challenges. With more people from different organizations on board, conflicts are bound to arise. The complex nature of these conflicts calls for specialized resolution strategies, which means more effort for the client managers. in order to look at the key conflicts and their resolution strategies in information technology projects, a case study approach for a single company making extensive use of multisourcing was adopted. After studying the previous literature on this subject and conducting extensive research through interviews of managers, the key conflict factors identified were power struggles, working in silos, knowledge and understanding gaps, withholding information and finger pointing. The resolution techniques adopted by managers were client moderated knowledge transfer sessions, client escalation, developing team motivation, effective communication and building personal rapport. The factors were found to be in line with the ones identified in the literature research. Once these factors were rated in terms of their significance and occurrence (by means of surveys), system dynamics was chosen as a modeling tool to capture the causal relationships that the conflict and resolution factors have with the system. System dynamics was chosen as it explicitly defines the cause effect relationships, interdependencies and feedback mechanisms. Based on this, simulation runs were done and sensitivity analyses for the individual impact of all the conflict and resolution factors were carried out. it was found that the descending order of criticality for the conflicts in the case of the company was knowledge gaps, withholding information, finger pointing, working in silos and power struggle. The descending order of the available resolution options was effective communication, personal rapport, client moderated knowledge transfers, motivation and client escalations. This sequencing can help the managers at the company to address the key conflicts in order of priority. They can then devise their strategy by combining multiple resolution options and gauging the impact of their strategy (vide the system dynamics model constructed in this thesis) as is pertinent to their organization.by Nirmalya Banerjee.S.M.in Engineering and Managemen
Panchayat Irrigation Management : A Case Study of Institutional Reforms Programme over Teesta Command in West Bengal
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.This article studies the role played by the constitutionally empowered Panchayati Raj Institutions over a large irrigation system in West Bengal. The article tries to capture the linkages and the dynamics governing interaction between the 'Gram Panchayats' and the Water User Associations. The inferences are drawn from observed phenomenon pertaining to the role and relationship between the two sets of institutions over the Command Area Development Authority Programme (CADAP). While the advent of the canal water has created an agrarian dynamism over the canal command particularly among the marginal and landless farmers through boro-paddy cultivation, the process of institutionalizing farmers’ participation left much to be desired. While the representatives of the Water User Associations often faltered to draw collective action from the farmers, the political actors proved to be much stronger. However even these actors were not proactive and responded only to crisis situations. Thus the system continues to operate at the sub-optimal level and seems to have achieved a low level of equilibrium
Controlled transportation of mesoscopic particles by enhanced spin orbit interaction of light in an optical trap
We study the effects of the spin orbit interaction (SOI) of light in an
optical trap and show that the propagation of the tightly focused trapping beam
in a stratified medium can lead to significantly enhanced SOI. For a plane
polarized incident beam the SOI manifests itself by giving rise to a strong
anisotropic linear diattenuation effect which produces polarization-dependent
off-axis high intensity side lobes near the focal plane of the trap. Single
micron-sized asymmetric particles can be trapped in the side lobes, and
transported over circular paths by a rotation of the plane of input
polarization. We demonstrate such controlled motion on single pea-pod shaped
single soft oxometalate (SOM) particles of dimension around m
over lengths up to 15 m . The observed effects are supported by
calculations of the intensity profiles based on a variation of the Debye-Wolf
approach. The enhanced SOI could thus be used as a generic means of
transporting mesoscopic asymmetric particles in an optical trap without the use
of complex optical beams or changing the alignment of the beam into the trap.Comment: 9 pages, 7 figure
Diffraction of an Off-axis Vector-Beam by a Tilted Aperture
Manifestations of orbital angular momentum induced effects in the diffraction
of a radially polarized vector beam by an off-axis tilted aperture are studied
both experimentally and theoretically. Experiments were carried out to extract
the degree of circular polarization, which was shown to be proportional to the
on-axis component of the spin angular momentum density. We report a clear
separation of the regions of dominance of the right and left circular
polarizations associated with positive and negative topological charges
respectively, which is reminiscent of the standard vortex-induced transverse
shift, albeit in the diffraction scenario. The experimental results are
supported by model simulations and the agreement is quite satisfactory. The
results are useful to appreciate the orbit-orbit related effects due to
unavoidable misalignment problems (especially for vortex beams)
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