D. Naik - Academia.edu (original) (raw)
Papers by D. Naik
Annals of internal medicine, 1976
Case Reports, 2014
Eighty per cent of primary hyperparathyroidism cases are caused by parathyroid adenoma while near... more Eighty per cent of primary hyperparathyroidism cases are caused by parathyroid adenoma while nearly 16% of ectopic parathyroid adenomas have been found to be the aetiology. 1 A 50-year-old man presented with pain in the back and knees for 4 years. He was initially evaluated elsewhere and was detected to have hypercalcaemia. No other investigations were done at the other facility. He was then evaluated in our institution for the persistence of hypercalcaemia and recently deranged renal function. His blood investigations revealed: serum calcium 12 mg% (normal (N) 8.3-10.4), phosphorus 1.8 mg% (N 2.5-4.6), creatinine 2 mg% (N 0.7-1.4), estimated glomerular filtration rate (eGFR) 56 mL/min/body surface area (BSA), 25 (OH)-vitamin-D 20.03 ng/mL (N 20-32) and intact parathyroid hormone (iPTH) 644 pg/mL (N 8-74). An ultrasonography of his abdomen revealed mild nephrocalcinosis bilaterally. His bone mineral density showed a t score of −3 in forearm as compared with spine (−1.2) and neck of femur (−1.6). The ultrasonography of the neck did not show any parathyroid adenoma. He underwent a technetium-99m ( 99m Tc) sestamibi scan as well as a single photon emission CT (SPECT), which revealed an ectopic parathyroid adenoma below the lower pole of the right lobe of thyroid (figures 1 and 2). He underwent a focal parathyroid surgery via the cervical approach and the adenoma was located in the thymus; it was resected and removed. His intact parathyroid hormone (iPTH) and serum calcium levels measured 24 h after surgery, within normal limits. On the day of discharge, his corrected serum calcium level was 8.83 mg%. At present, he is asymptomatic, on regular follow-up and has normal serum calcium levels.
New England Journal of Medicine, 1974
Medical Intelligence from The New England Journal of Medicine Diagonal Ear-Lobe Crease: Prevale... more Medical Intelligence from The New England Journal of Medicine Diagonal Ear-Lobe Crease: Prevalence and Implications as a Coronary Risk Factor.
Journal of Cancer Research and Therapeutics, 2011
Oral squamous cell carcinoma (OSCC) is one of the most common malignancies recognized nowadays. I... more Oral squamous cell carcinoma (OSCC) is one of the most common malignancies recognized nowadays. Its early detection is the better alternative to provide a good quality of life for the patients. During the last years, several studies have identified potential biomarkers of OSCC progression and prognosis. The phosphodiesterases (PDEs) are responsible for the hydrolysis of the second messengers with a fundamental role in the transduction of the intracellular signals. Variations in PDE activity have been correlated to different pathological mechanisms, such as cellular differentiation, apoptosis, and tumor invasivity. PDEs are also known to play a role in tumor growth by influencing angiogenesis. To estimate and compare serum PDE levels in healthy controls and biopsy-proven oral cancer patients before definitive therapy. Institutional Ethics Committee gave us the permission to conduct this study. After obtaining consent from biopsy-proven oral cancer patients (n = 39) (before onset of any definitive treatment) and age- and sex-matched healthy controls (n = 20), 2 ml of blood was collected in plain vacutainers. After clot formation, samples were centrifuged and serum was collected for estimation of PDE. Kruskal-Wallis test; Mann-Whitney Test. Pretreatment PDE levels were significantly elevated in oral cancer patients (P<0.0001) as compared with the controls and also there was a significant increase in PDE levels (P<0.001) with advancing stage in oral cancer patients. This may implicate a role for serum PDE in pathophysiology of oral cancer.
Circulation, 1976
Seventy-two patients with trifasicular disease were followed for an average of 40 months followin... more Seventy-two patients with trifasicular disease were followed for an average of 40 months following permanent pacemaker insertion. The indications for pacemaker insertion were either electrocardiographic evidence of complete heart block with a wide QRS escape complex or a pattern of bifasicular block with either periods of Mobitz type II atrioventricular (A-V) block or a documented history of syncope. The patients were then divided into three groups depending on subsequent change in A-V conduction. There were 31 (43%) patients with no change in A-V conduction, 17 (24%) with increasing A-V block, and 24 (33%) with decreasing A-V block. The characteristics of these three groups, including age and sex distribution, were compared and found to be similar. The incidence of previous transmural myocardial infarction as determined by electrocardiographic criteria was higher in the group with decreasing block. Survival curves showed a significantly decreased probablity of surviving for those with decreasing block compared to both those with increasing block and those with no charge in conduction (P less than 0.03). We conclude that the probability of long-term survival was less in the group with decreasing block. This finding may be related to the greater prevalence of coronary heart disease in the patients.
British Journal of Radiology, 1968
Meningomyelocoeles are associated with gross ab-normalities in the central nervous system and, in... more Meningomyelocoeles are associated with gross ab-normalities in the central nervous system and, in particular, the complex abnormality of the medulla and the cervical cord described by Cleland (1883), and usually known as the Arnold Chiari deformity (Schwalbe and Gredig, ...
CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference, 2009
Ultracold Fermi-Fermi mixtures offer intriguing possibilities to study fermionic pairing phenomen... more Ultracold Fermi-Fermi mixtures offer intriguing possibilities to study fermionic pairing phenomena and superfluidity in new regimes beyond the currently employed spin mixtures of a single species. We produce a doubly-degenerate mixture of 6Li and 40K atoms by evaporative cooling in an optical dipole trap. The trapping light is provided by a 100-W fiber laser operating near a wavelength of 1070nm.
BMC bioinformatics, Jan 11, 2004
Recent technological advances in mass spectrometry pose challenges in computational mathematics a... more Recent technological advances in mass spectrometry pose challenges in computational mathematics and statistics to process the mass spectral data into predictive models with clinical and biological significance. We discuss several classification-based approaches to finding protein biomarker candidates using protein profiles obtained via mass spectrometry, and we assess their statistical significance. Our overall goal is to implicate peaks that have a high likelihood of being biologically linked to a given disease state, and thus to narrow the search for biomarker candidates. Thorough cross-validation studies and randomization tests are performed on a prostate cancer dataset with over 300 patients, obtained at the Eastern Virginia Medical School using SELDI-TOF mass spectrometry. We obtain average classification accuracies of 87% on a four-group classification problem using a two-stage linear SVM-based procedure and just 13 peaks, with other methods performing comparably. Modern featu...
Multi-species mixtures of ultracold atoms are currently being studied intensively. The areas of f... more Multi-species mixtures of ultracold atoms are currently being studied intensively. The areas of focus include, but are not limited to condensed matter and quantum statistical effects, interaction-tuning by photo- and magneto-association, production of (degenerate) ultracold molecules, and so on. In the specific case of NaRb, predictions exist regarding Feshbach resonances [1], miscibility [2] and macroscopic quantum transitions [3]. We describe
The New Zealand medical journal, Jan 24, 2010
The aim of this project was to employ interdepartmental and cross district health board collabora... more The aim of this project was to employ interdepartmental and cross district health board collaboration to reach a regional consensus on the management of patients who may benefit from carotid endarterectomy. All regional stroke physicians, neurologists, and vascular surgeons met to review relevant literature and local audits and to discuss best management strategies suited to the region. A consensus statement was agreed upon and is presented here along with a summary of the supporting scientific evidence. Regional interdisciplinary collaboration proved an effective way to reach a carotid endarterectomy management consensus across a wider geographical area that is served by a single vascular surgery department. This approach could serve as a model for other regional initiatives.
Earth & Space 2008, 2008
Test methods to obtain constitutive material properties of fabrics used for containing high-speed... more Test methods to obtain constitutive material properties of fabrics used for containing high-speed projectiles are presented. The material models are general enough to be used for both static and dynamic/explicit finite element analyses. Tension Tests were conducted to develop the longitudinal and transverse material properties. Trellising Picture Frame Shear Tests were used in investigating the shear resistance properties of the fabrics, followed by friction tests to determine the coefficient of friction between fabric layers. In addition to these basic material tests, experiments were conducted on systems built with fabric wraps. Ballistic tests of containment wraps subjected to a high velocity projectile were carried out at NASA-Glenn Research Center. These tests have provided benchmark results to validate the finite element methodology used for the analysis of the containment systems.
Physical Review Letters, 2009
We investigate the collisional stability of a sample of 40 K atoms immersed in a tunable spin mix... more We investigate the collisional stability of a sample of 40 K atoms immersed in a tunable spin mixture of 6 Li atoms. In this three-component Fermi-Fermi mixture, we find very low loss rates in a wide range of interactions as long as molecule formation of 6 Li is avoided. The stable fermionic mixture with two resonantly interacting spin states of one species together with another species is a promising system for a broad variety of phenomena in few-and many-body quantum physics. PACS numbers: 34.50.-s, 67.85.Lm, 05.30.Fk The groundbreaking achievements in experiments with ultracold Fermi gases have opened up unprecedented possibilities to study new regimes of strongly interacting quantum matter [1, 2, 3]. Recent experiments have opened up two important new research frontiers with fermionic atoms that go beyond the two-component spin mixtures so far exploited in the field. Mixtures involving three different spin states [4, 5] and mixtures of different fermionic species [6, 7, 8] have produced first exciting results like the demonstration of fermionic Efimov states [9, 10] and the creation of Fermi-Fermi molecules .
Physical Review Letters, 2008
We report on the observation of Feshbach resonances in an ultracold mixture of two fermionic spec... more We report on the observation of Feshbach resonances in an ultracold mixture of two fermionic species, 6 Li and 40 K. The experimental data are interpreted using a simple asymptotic bound state model and full coupled channels calculations. This unambiguously assigns the observed resonances in terms of various s-and p-wave molecular states and fully characterizes the ground-state scattering properties in any combination of spin states.
Physical Review Letters, 2011
We report on the expansion of an ultracold Fermi-Fermi mixture of 6 Li and 40 K under conditions ... more We report on the expansion of an ultracold Fermi-Fermi mixture of 6 Li and 40 K under conditions of strong interactions controlled via an interspecies Feshbach resonance. We study the expansion of the mixture after release from the trap and, in a narrow magnetic field range, we observe two phenomena related to hydrodynamic behavior. The common inversion of the aspect ratio is found to be accompanied by a collective effect where both species stick together and expand jointly despite of their widely different masses. Our work constitutes a major experimental step for a controlled investigation of the many-body physics of this novel strongly interacting quantum system.
Physical Review A, 2005
We created sodium Bose-Einstein condensates in an optically plugged quadrupole magnetic trap (OPT... more We created sodium Bose-Einstein condensates in an optically plugged quadrupole magnetic trap (OPT). A focused, 532nm laser beam repelled atoms from the coil center where Majorana loss is significant. We produced condensates of up to 3 × 10 7 atoms, a factor of 60 improvement over previous work [1], a number comparable to the best all-magnetic traps, and transferred up to 9 × 10 6 atoms into a purely optical trap. Due to the tight axial confinement and azimuthal symmetry of the quadrupole coils, the OPT shows promise for creating Bose-Einstein condensates in a ring geometry.
Physical Review A, 2005
We have created a Bose-Einstein condensate whose spin orientation is metastable. Condensates were... more We have created a Bose-Einstein condensate whose spin orientation is metastable. Condensates were transferred into a quadrupole magnetic trap, where Majorana transitions limited the lifetime to a few hundred milliseconds, about 30 times the trapping period. Atoms held in the trap frequently displayed a ring-shaped time-of-flight distribution. We speculate that such a ring could be either a quantized vortex or a feature of the Majorana loss dynamics in the quantum regime.
International Journal of Impact Engineering, 2009
Explicit finite element analysis Strain-rate effects Engine fan blade out containment a b s t r a... more Explicit finite element analysis Strain-rate effects Engine fan blade out containment a b s t r a c t
Annals of internal medicine, 1976
Case Reports, 2014
Eighty per cent of primary hyperparathyroidism cases are caused by parathyroid adenoma while near... more Eighty per cent of primary hyperparathyroidism cases are caused by parathyroid adenoma while nearly 16% of ectopic parathyroid adenomas have been found to be the aetiology. 1 A 50-year-old man presented with pain in the back and knees for 4 years. He was initially evaluated elsewhere and was detected to have hypercalcaemia. No other investigations were done at the other facility. He was then evaluated in our institution for the persistence of hypercalcaemia and recently deranged renal function. His blood investigations revealed: serum calcium 12 mg% (normal (N) 8.3-10.4), phosphorus 1.8 mg% (N 2.5-4.6), creatinine 2 mg% (N 0.7-1.4), estimated glomerular filtration rate (eGFR) 56 mL/min/body surface area (BSA), 25 (OH)-vitamin-D 20.03 ng/mL (N 20-32) and intact parathyroid hormone (iPTH) 644 pg/mL (N 8-74). An ultrasonography of his abdomen revealed mild nephrocalcinosis bilaterally. His bone mineral density showed a t score of −3 in forearm as compared with spine (−1.2) and neck of femur (−1.6). The ultrasonography of the neck did not show any parathyroid adenoma. He underwent a technetium-99m ( 99m Tc) sestamibi scan as well as a single photon emission CT (SPECT), which revealed an ectopic parathyroid adenoma below the lower pole of the right lobe of thyroid (figures 1 and 2). He underwent a focal parathyroid surgery via the cervical approach and the adenoma was located in the thymus; it was resected and removed. His intact parathyroid hormone (iPTH) and serum calcium levels measured 24 h after surgery, within normal limits. On the day of discharge, his corrected serum calcium level was 8.83 mg%. At present, he is asymptomatic, on regular follow-up and has normal serum calcium levels.
New England Journal of Medicine, 1974
Medical Intelligence from The New England Journal of Medicine Diagonal Ear-Lobe Crease: Prevale... more Medical Intelligence from The New England Journal of Medicine Diagonal Ear-Lobe Crease: Prevalence and Implications as a Coronary Risk Factor.
Journal of Cancer Research and Therapeutics, 2011
Oral squamous cell carcinoma (OSCC) is one of the most common malignancies recognized nowadays. I... more Oral squamous cell carcinoma (OSCC) is one of the most common malignancies recognized nowadays. Its early detection is the better alternative to provide a good quality of life for the patients. During the last years, several studies have identified potential biomarkers of OSCC progression and prognosis. The phosphodiesterases (PDEs) are responsible for the hydrolysis of the second messengers with a fundamental role in the transduction of the intracellular signals. Variations in PDE activity have been correlated to different pathological mechanisms, such as cellular differentiation, apoptosis, and tumor invasivity. PDEs are also known to play a role in tumor growth by influencing angiogenesis. To estimate and compare serum PDE levels in healthy controls and biopsy-proven oral cancer patients before definitive therapy. Institutional Ethics Committee gave us the permission to conduct this study. After obtaining consent from biopsy-proven oral cancer patients (n = 39) (before onset of any definitive treatment) and age- and sex-matched healthy controls (n = 20), 2 ml of blood was collected in plain vacutainers. After clot formation, samples were centrifuged and serum was collected for estimation of PDE. Kruskal-Wallis test; Mann-Whitney Test. Pretreatment PDE levels were significantly elevated in oral cancer patients (P<0.0001) as compared with the controls and also there was a significant increase in PDE levels (P<0.001) with advancing stage in oral cancer patients. This may implicate a role for serum PDE in pathophysiology of oral cancer.
Circulation, 1976
Seventy-two patients with trifasicular disease were followed for an average of 40 months followin... more Seventy-two patients with trifasicular disease were followed for an average of 40 months following permanent pacemaker insertion. The indications for pacemaker insertion were either electrocardiographic evidence of complete heart block with a wide QRS escape complex or a pattern of bifasicular block with either periods of Mobitz type II atrioventricular (A-V) block or a documented history of syncope. The patients were then divided into three groups depending on subsequent change in A-V conduction. There were 31 (43%) patients with no change in A-V conduction, 17 (24%) with increasing A-V block, and 24 (33%) with decreasing A-V block. The characteristics of these three groups, including age and sex distribution, were compared and found to be similar. The incidence of previous transmural myocardial infarction as determined by electrocardiographic criteria was higher in the group with decreasing block. Survival curves showed a significantly decreased probablity of surviving for those with decreasing block compared to both those with increasing block and those with no charge in conduction (P less than 0.03). We conclude that the probability of long-term survival was less in the group with decreasing block. This finding may be related to the greater prevalence of coronary heart disease in the patients.
British Journal of Radiology, 1968
Meningomyelocoeles are associated with gross ab-normalities in the central nervous system and, in... more Meningomyelocoeles are associated with gross ab-normalities in the central nervous system and, in particular, the complex abnormality of the medulla and the cervical cord described by Cleland (1883), and usually known as the Arnold Chiari deformity (Schwalbe and Gredig, ...
CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference, 2009
Ultracold Fermi-Fermi mixtures offer intriguing possibilities to study fermionic pairing phenomen... more Ultracold Fermi-Fermi mixtures offer intriguing possibilities to study fermionic pairing phenomena and superfluidity in new regimes beyond the currently employed spin mixtures of a single species. We produce a doubly-degenerate mixture of 6Li and 40K atoms by evaporative cooling in an optical dipole trap. The trapping light is provided by a 100-W fiber laser operating near a wavelength of 1070nm.
BMC bioinformatics, Jan 11, 2004
Recent technological advances in mass spectrometry pose challenges in computational mathematics a... more Recent technological advances in mass spectrometry pose challenges in computational mathematics and statistics to process the mass spectral data into predictive models with clinical and biological significance. We discuss several classification-based approaches to finding protein biomarker candidates using protein profiles obtained via mass spectrometry, and we assess their statistical significance. Our overall goal is to implicate peaks that have a high likelihood of being biologically linked to a given disease state, and thus to narrow the search for biomarker candidates. Thorough cross-validation studies and randomization tests are performed on a prostate cancer dataset with over 300 patients, obtained at the Eastern Virginia Medical School using SELDI-TOF mass spectrometry. We obtain average classification accuracies of 87% on a four-group classification problem using a two-stage linear SVM-based procedure and just 13 peaks, with other methods performing comparably. Modern featu...
Multi-species mixtures of ultracold atoms are currently being studied intensively. The areas of f... more Multi-species mixtures of ultracold atoms are currently being studied intensively. The areas of focus include, but are not limited to condensed matter and quantum statistical effects, interaction-tuning by photo- and magneto-association, production of (degenerate) ultracold molecules, and so on. In the specific case of NaRb, predictions exist regarding Feshbach resonances [1], miscibility [2] and macroscopic quantum transitions [3]. We describe
The New Zealand medical journal, Jan 24, 2010
The aim of this project was to employ interdepartmental and cross district health board collabora... more The aim of this project was to employ interdepartmental and cross district health board collaboration to reach a regional consensus on the management of patients who may benefit from carotid endarterectomy. All regional stroke physicians, neurologists, and vascular surgeons met to review relevant literature and local audits and to discuss best management strategies suited to the region. A consensus statement was agreed upon and is presented here along with a summary of the supporting scientific evidence. Regional interdisciplinary collaboration proved an effective way to reach a carotid endarterectomy management consensus across a wider geographical area that is served by a single vascular surgery department. This approach could serve as a model for other regional initiatives.
Earth & Space 2008, 2008
Test methods to obtain constitutive material properties of fabrics used for containing high-speed... more Test methods to obtain constitutive material properties of fabrics used for containing high-speed projectiles are presented. The material models are general enough to be used for both static and dynamic/explicit finite element analyses. Tension Tests were conducted to develop the longitudinal and transverse material properties. Trellising Picture Frame Shear Tests were used in investigating the shear resistance properties of the fabrics, followed by friction tests to determine the coefficient of friction between fabric layers. In addition to these basic material tests, experiments were conducted on systems built with fabric wraps. Ballistic tests of containment wraps subjected to a high velocity projectile were carried out at NASA-Glenn Research Center. These tests have provided benchmark results to validate the finite element methodology used for the analysis of the containment systems.
Physical Review Letters, 2009
We investigate the collisional stability of a sample of 40 K atoms immersed in a tunable spin mix... more We investigate the collisional stability of a sample of 40 K atoms immersed in a tunable spin mixture of 6 Li atoms. In this three-component Fermi-Fermi mixture, we find very low loss rates in a wide range of interactions as long as molecule formation of 6 Li is avoided. The stable fermionic mixture with two resonantly interacting spin states of one species together with another species is a promising system for a broad variety of phenomena in few-and many-body quantum physics. PACS numbers: 34.50.-s, 67.85.Lm, 05.30.Fk The groundbreaking achievements in experiments with ultracold Fermi gases have opened up unprecedented possibilities to study new regimes of strongly interacting quantum matter [1, 2, 3]. Recent experiments have opened up two important new research frontiers with fermionic atoms that go beyond the two-component spin mixtures so far exploited in the field. Mixtures involving three different spin states [4, 5] and mixtures of different fermionic species [6, 7, 8] have produced first exciting results like the demonstration of fermionic Efimov states [9, 10] and the creation of Fermi-Fermi molecules .
Physical Review Letters, 2008
We report on the observation of Feshbach resonances in an ultracold mixture of two fermionic spec... more We report on the observation of Feshbach resonances in an ultracold mixture of two fermionic species, 6 Li and 40 K. The experimental data are interpreted using a simple asymptotic bound state model and full coupled channels calculations. This unambiguously assigns the observed resonances in terms of various s-and p-wave molecular states and fully characterizes the ground-state scattering properties in any combination of spin states.
Physical Review Letters, 2011
We report on the expansion of an ultracold Fermi-Fermi mixture of 6 Li and 40 K under conditions ... more We report on the expansion of an ultracold Fermi-Fermi mixture of 6 Li and 40 K under conditions of strong interactions controlled via an interspecies Feshbach resonance. We study the expansion of the mixture after release from the trap and, in a narrow magnetic field range, we observe two phenomena related to hydrodynamic behavior. The common inversion of the aspect ratio is found to be accompanied by a collective effect where both species stick together and expand jointly despite of their widely different masses. Our work constitutes a major experimental step for a controlled investigation of the many-body physics of this novel strongly interacting quantum system.
Physical Review A, 2005
We created sodium Bose-Einstein condensates in an optically plugged quadrupole magnetic trap (OPT... more We created sodium Bose-Einstein condensates in an optically plugged quadrupole magnetic trap (OPT). A focused, 532nm laser beam repelled atoms from the coil center where Majorana loss is significant. We produced condensates of up to 3 × 10 7 atoms, a factor of 60 improvement over previous work [1], a number comparable to the best all-magnetic traps, and transferred up to 9 × 10 6 atoms into a purely optical trap. Due to the tight axial confinement and azimuthal symmetry of the quadrupole coils, the OPT shows promise for creating Bose-Einstein condensates in a ring geometry.
Physical Review A, 2005
We have created a Bose-Einstein condensate whose spin orientation is metastable. Condensates were... more We have created a Bose-Einstein condensate whose spin orientation is metastable. Condensates were transferred into a quadrupole magnetic trap, where Majorana transitions limited the lifetime to a few hundred milliseconds, about 30 times the trapping period. Atoms held in the trap frequently displayed a ring-shaped time-of-flight distribution. We speculate that such a ring could be either a quantized vortex or a feature of the Majorana loss dynamics in the quantum regime.
International Journal of Impact Engineering, 2009
Explicit finite element analysis Strain-rate effects Engine fan blade out containment a b s t r a... more Explicit finite element analysis Strain-rate effects Engine fan blade out containment a b s t r a c t