1,601 research outputs found
A Study on Solitary Nodule of the Thyroid
BACKGROUND AND OBJECTIVES:
Solitary nodule of the thyroid of discrete thyroid swelling is a common clinical entity and the incidence increases with age. About half of the patients with palpable nodular goitre are diagnosed as multinodular goitre. The importance of this clinical entity is that 10-20% of solitary
nodules of the thyroid could be malignant.
The approach to thyroid nodule management is a selective one, utilizing continually Improving diagnostic techniques to reliably identify patients with malignancy and certain benign conditions that require surgery thereby avoiding unnecessary thyroidectomy for all nodules.
A potentially curable cancer normally presents as a thyroid nodule and thereby the study of a solitary nodule gains importance. The main objectives of this study is To find the epidemiology,role of fine needle aspiration cytology &The incidence of malignancy in solitary nodule of the thyroid.
METHODS:
All patients admitted with a solitary nodule of the thyroid. Excluding Patients with severe comorbid illness and those with regional lymph adenopathy. A total of 100 consecutive patients with solitary nodule of the thyroid admitted were evaluated clinically, biochemically, radiologically and cytologically. The patients underwent Hyemithyroidectomy and the histopathology of the excised specimens were studied to evaluate the incidence of malignancy.
RESULTS:
Solitary nodule of the thyroids are common in third decade of life, females are more commonly affected than male, incidence of maligancy found to be more common in male who where in age group from 21 – 50yrs. Most common clinical symptoms swelling and most common post operative complication is hypothyroidism seen in 10% of cases. Retrospective comparison with Histopathology of excised specimen revealed a false negative report in FNAC in detecting malignancy in 16 cases of malignant nodules.
CONCLUSION:
Solitary nodule of the thyroid was found to be more common in young and middle aged patients. AMONG WHICH IT IS 8 times more common in females than males. Majority of the solitary nodule were dominant nodules of a multinodular goiter. In the individuals admitted with solitary nodule of thyroid and managed by hemithyroidectomy, the incidence of malignancy was 16%. Fine needle aspiration cytology, now considered as the gold standard diagnostic test in the evaluation of a thyroid nodule revealed false negative report in 16 patients in this study. Ultra
sonogram and nuclear scans are also useful tests, but are best used in conjuction with fine needle aspiration cytology. Solitary nodule of the thyroid is a common entity whereas malignancy although rare needs a selective approach for further management and follow up
Perfect Teleportation, Quantum state sharing and Superdense Coding through a Genuinely Entangled Five-qubit State
We investigate the usefulness of a recently introduced five qubit state by
Brown \it et al. \normalfont \cite{Brown} for quantum teleportation, quantum
state sharing and superdense coding. It is shown that this five-qubit state can
be utilized for perfect teleportation of arbitrary single and two qubit
systems. We devise various schemes for quantum state sharing of an arbitrary
single and two particle state via cooperative teleportation. We later show that
this state can be used for superdense coding as well. It is found that five
classical bits can be sent by sending only three quantum bits.Comment: 8 Pages, added sections on state sharin
Landauer-B\"uttiker approach for hyperfine mediated electronic transport in the integer quantum Hall regime
The interplay of spin-polarized electronic edge states with the dynamics of
the host nuclei in quantum Hall systems presents rich and non-trivial transport
physics. Here, we develop a Landauer-B\"uttiker approach to understand various
experimental features observed in the integer quantum Hall set ups featuring
quantum point contacts. The approach developed here entails a phenomenological
description of spin resolved inter-edge scattering induced via hyperfine
assisted electron-nuclear spin flip-flop processes. A self-consistent
simulation framework between the nuclear spin dynamics and edge state
electronic transport is presented in order to gain crucial insights into the
dynamic nuclear polarization effects on electronic transport and in turn the
electron-spin polarization effects on the nuclear spin dynamics. In particular,
we show that the hysteresis noted experimentally in the conductance-voltage
trace as well as in the resistively detected NMR lineshape results from a lack
of quasi-equilibrium between electronic transport and nuclear polarization
evolution. In addition, we present circuit models to emulate such hyperfine
mediated transport effects to further facilitate a clear understanding of the
electronic transport processes occurring around the quantum point contact.
Finally, we extend our model to account for the effects of quadrupolar
splitting of nuclear levels and also depict the electronic transport signatures
that arise from single and multi-photon processes.Comment: 21 pages, 8 figure
Turning turtle
In September this year, the Tamil Nadu Fisheries Department issued an order that banned all forms of fishing within a radius of 5 nautical miles (9.3 km) at 90 sites along the State’s coastline. It was passed to safeguard migrating olive ridley sea turtles. Extending from January to the end of April, the ban is applicable across eight coastal districts — from Chennai in the north to Kanyakumari in the south
DEVELOPING A PERFORMANCE IMPORTANCE MATRIX FOR A PUBLIC SECTOR BUS TRANSPORT COMPANY: A CASE STUDY
This paper presents a study of comparison of the importance attached by the service providers’ and the customers’ with respect to eighteen service characteristics towards the public transportation services provided by a bus company. The survey was conducted in three bus depots in one division of a state road transport undertaking (SRTU) in south India. The importance the SRTU and the customers attach to these characteristics indicates significant differences. This reveals the existence of a gap between customers’ expectations and the service provided by the company. Finally the customer retention and customer development criteria have been. identified.Performance importance matrix, Customer expectations, Public bus transport, Radar chart.
Development of Subcarangiform Bionic Robotic Fish Propelled by Shape Memory Alloy Actuators
In this paper, a shape memory alloy (SMA) actuated subcarangiform robotic fish has been demonstrated using a spring based propulsion mechanism. The bionic robotic fish developed using SMA spring actuators and light weight 3D printed components can be employed for under water applications. The proposed SMA spring-based design without conventional motor and other rotary actuators was able to achieve two-way shape memory effect and has reproduced the subcarangiform locomotion pattern. The positional kinematic model has been developed and the dynamics of the proposed mechanism were analysed and simulated using Automated Dynamic Analysis of Mechanical Systems (ADAMS). An open loop Arduino-relay based switching control has been adopted to control the periodic actuation of the SMA spring mechanism. The undulation of caudal fin in air and water medium has been analysed. The caudal fin and posterior body of the developed fish prototype have taken part in undulation resembling subcarangiform locomotion pattern and steady swimming was achieved in water with a forward velocity of 24.5 mm/s. The proposed design is scalable, light weight and cost effective which may be suitable for underwater surveillance application
Resistively-detected NMR lineshapes in a quasi-one dimensional electron system
We observe variation in the resistively-detected nuclear magnetic resonance
(RDNMR) lineshapes in quantum Hall breakdown. The breakdown is locally occurred
in a gate-defined quantum point contact (QPC) region. Of particular interest is
the observation of a dispersive lineshape occured when the bulk 2D electron gas
(2DEG) is set to and the QPC filling factor to the vicinity
of , strikingly resemble the dispersive lineshape observed
on a 2D quantum Hall state. This previously unobserved lineshape in a QPC
points to simultaneous occurrence of two hyperfine-mediated spin flip-flop
processes within the QPC. Those events give rise to two different sets of
nuclei polarized in the opposite direction and positioned at a separate region
with different degree of electronic polarizations.Comment: Accepted as a rapid communication in PR
Rectification by charging -- the physics of contact-induced current asymmetry in molecular conductors
We outline the qualitatively different physics behind charging-induced
current asymmetries in molecular conductors operating in the weakly interacting
self-consistent field (SCF) and the strongly interacting Coulomb Blockade (CB)
regimes. A conductance asymmetry arises in SCF because of the unequal
mean-field potentials that shift a closed-shell conducting level differently
for positive and negative bias. A very different current asymmetry arises for
CB due to the unequal number of open-shell excitation channels at opposite bias
voltages. The CB regime, dominated by single charge effects, typically requires
a computationally demanding many-electron or Fock space description. However,
our analysis of molecular Coulomb Blockade measurements reveals that many novel
signatures can be explained using a {{simpler}} orthodox model that involves an
incoherent sum of Fock space excitations and {\it{hence treats the molecule as
a metallic dot or an island}}. This also reduces the complexity of the Fock
space description by just including various charge configurations only, thus
partially underscoring the importance of electronic structure, while retaining
the essence of the single charge nature of the transport process. We finally
point out, however, that the inclusion of electronic structure and hence
well-resolved Fock space excitations is crucial in some notable examples.Comment: 12 pages, 10 figure
- …