In the presence of perturbations of the thermospheric auroral region produced by traveling ionosp... more In the presence of perturbations of the thermospheric auroral region produced by traveling ionospheric disturbances during the propagation of atmospheric gravity waves, an analytical expression of the velocity of the thermospheric plasma is derived through magnetohydrodynamic formalism. The expressions of the Joule heating and the viscous heating are derived, and their rates of variation are presented. A threshold height for their transition has been determined from their ratio, which is in agreement with the experimental data. The analysis indicates that the time taken by the thermospheric plasma to reach a steady-state corresponds to the nature of the traveling ionospheric disturbances in the medium.
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
Schumann resonances (SR) observations from a tropical region near Kolkata at the estuary of the r... more Schumann resonances (SR) observations from a tropical region near Kolkata at the estuary of the river Ganges merging into the Bay-of-Bengal (21.48° N, 88.61° E) are being made frequently. Several Q-bursts spectra are observed. Strong ELF transients are detected in the recorded data of SR. The dynamic evolution of electric and magnetic field components of the Q-bursts will be presented in this paper. Time series evolutions of signals of several Q-bursts are analyzed in the present study. It is observed that, the Q-burst amplitudes from 1 to 300 Hz of Qbursts spectra for 1 sec FFT reaches about-47 dB near the first mode of SR frequency. This shows that Q-burst has the tendency to dominate within 1 to 300 Hz.
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
Auroral electric field is a probable source of Atmospheric Gravity Waves (AGW) in the thermospher... more Auroral electric field is a probable source of Atmospheric Gravity Waves (AGW) in the thermospheric region of Auroral zone of the ionosphere and associated Traveling Ionospheric Disturbances (TID). This field is considered to be active through Lorentz force and Joule dissipation that influence the neutral gas of the medium through collision. The process introduces the short-range gravity waves. The expressions for the low frequency part of the fractional pressure variations have been derived within the auroral region of the ionosphere. The results of numerical analyses are presented graphically.
WKB method has been applied to solve some integral equations arising out of wave-particle interac... more WKB method has been applied to solve some integral equations arising out of wave-particle interaction within the upper atmosphere. Problem of ELF propagation through the Earth-Ionosphere waveguide has been investigated taking into account the inhomogeneities due to asymmetry of the day and night time ionosphere and variations of conductivity of the ionosphere. The results of numerical solutions are graphically presented through appropriate data and compared with previous results.
Well log data of thirty (30) boreholes from central part of Jharia coalfield have been analysed f... more Well log data of thirty (30) boreholes from central part of Jharia coalfield have been analysed for estimation of petrophysical and rock mechanical properties of coal seams to facilitate assessment of Coal Bed Methane (CBM) reservoir potentiality of those coal seam. Wells from Jharia area showed 18 major correlatable seams, intersected between 214 and 1324 m depth. The resistivity, density and natural gamma ray log data from the wells of the study area have been utilized for: (a) Estimation of permeability of coal seams from resistivity log data; (b) Computation of in-situ stress magnitudes—vertical stress, effective vertical stress and effective horizontal stress at seam horizons; (c) Establish relationship between in-situ stress and permeability; (d) Estimation of gas content of coal seams and identification of most potential zones for CBM exploration. It is observed that the permeability values ranging from 0.82 to 1.12 md with average gas content of 11.50 to 11.75 cc/gm. By comparing gas content, coal seam thickness as well as coal bed permeability of these major coal seams, the most viable CBM potential zone is mapped for this area.
Methods in molecular biology (Clifton, N.J.), 2015
T cells are an immune cell lineage that play a central role in protection against pathogen infect... more T cells are an immune cell lineage that play a central role in protection against pathogen infection. Antigen, in the form of pathogen-derived peptides, stimulates the T-cell receptor (TCR), leading to activation of the transcription factor, nuclear factor kappa B (NF-κB). The subsequent NF-κB-dependent gene expression program drives expansion and effector differentiation of antigen-specific T cells, leading to the adaptive anti-pathogen immune response. The cell surface TCR transmits activating signals to cytosolic NF-κB by a complex signaling cascade, in which the adapter protein Bcl10 plays a key role. We have previously demonstrated that TCR engagement leads to the formation of cytosolic Bcl10 clusters, called POLKADOTS, that provide a platform for the assembly of the terminal signaling complex that ultimately mediates NF-κB activation. In this chapter, we describe the methods utilized to visualize the formation of TCR-induced POLKADOTS and to study the temporal association betw...
Continuous recording of a subionospheric transmitted signal at 16.4 kHz from Novik, Norway (66°5 ... more Continuous recording of a subionospheric transmitted signal at 16.4 kHz from Novik, Norway (66°5 8´ N, 13° 54´ E) is being carried out in Kolkata (22° 34´ N, 88° 30´ E). The effects of recent solar eclipse on August 1, 2008 over this transmitted signal have been reported in this paper. The variations of normalized amplitude of this signal and its phase retardation in the path during the solar eclipse are measured which show significant deviations from their usual values for the same period of the control days.
The atmospheric radio noise field strength (ARNFS) at 700 Hz and 2100 Hz over Kolkata (Lat. 22.56... more The atmospheric radio noise field strength (ARNFS) at 700 Hz and 2100 Hz over Kolkata (Lat. 22.56 • N, Long. 88.5 • E) exhibits various characteristic patterns of diurnal and seasonal variations. Some distinctive features at these two frequencies have been observed in respect of the level of ARNFS during all the months, the fall of level from nighttime to daytime value, the correlation in sunrise time and the role of cloud activity upon the seasonal maximum. The outcome of analysis of the recorded data will be presented in this paper.
Antibodies to Coxiella burnetii have been found in the Danish dairy cattle population with high l... more Antibodies to Coxiella burnetii have been found in the Danish dairy cattle population with high levels of herd and within herd seroprevalences. However, the prevalence of antibodies to C. burnetii in Danish beef cattle remains unknown. The objectives of this study were to (1) estimate the prevalence and (2) identify risk factors associated with C. burnetii seropositivity in Danish beef and dairy cattle based on sampling at slaughter. Eight hundred blood samples from slaughtered cattle were collected from six Danish slaughter houses from August to October 2012 following a random sampling procedure. Blood samples were tested by a commercially available C. burnetii antibody ELISA kit. A sample was defined positive if the sample-to-positive ratio was greater than or equal to 40. Animal and herd information were extracted from the Danish Cattle Database. Apparent (AP) and true prevalences (TPs) specific for breed, breed groups, gender and herd type; and breed-specific true prevalences wi...
TCR-mediated activation of the transcription factor NF-κB is required for T cell proliferation, s... more TCR-mediated activation of the transcription factor NF-κB is required for T cell proliferation, survival, and effector differentiation. Although this pathway is the subject of intense study, it is not known whether TCR signaling to NF-κB is digital (switch-like) or analog in nature. Through analysis of the phosphorylation and degradation of IκBα and the nuclear translocation and phosphorylation of the NF-κB subunit RelA, we show that TCR-directed NF-κB activation is digital. Furthermore, digitization occurs well upstream of the IκB kinase complex, as protein kinase C θ translocation to the immunologic synapse and activation-associated aggregation of Bcl10 and Malt1 also demonstrate both digital behavior and high correlation with RelA nuclear translocation. Thus, similar to the TCR-to-MAPK signaling cascade, analog Ag inputs are converted to digital activation outputs to NF-κB at an early step downstream of TCR ligation.
Journal of Atmospheric and Solar-Terrestrial Physics, 2010
The variation of the first Schumann Resonance (SR) frequency spectra observed from the recorded d... more The variation of the first Schumann Resonance (SR) frequency spectra observed from the recorded data over Kolkata (22.56°N, 88.5°E) during a solar proton event (SPE) on July 14, 2000 has been presented. It shows increase in frequency during X-ray bursts and decrease during the ...
Accurate prediction of in-situ stress directions plays a key role in any Coal Bed Methane (CBM) e... more Accurate prediction of in-situ stress directions plays a key role in any Coal Bed Methane (CBM) exploration and exploitation project in order to estimate the production potential of the CBM reservoirs. Permeability is one of the most important factors for determination of CBM ...
The adaptor protein Bcl10 is a critically important mediator of T cell receptor (TCR)-to-NF-kB si... more The adaptor protein Bcl10 is a critically important mediator of T cell receptor (TCR)-to-NF-kB signaling. Bcl10 degradation is a poorly understood biological phenomenon suggested to reduce TCR activation of NF-kB. Here we have shown that TCR engagement triggers the degradation of Bcl10 in primary effector T cells but not in naive T cells. TCR engagement promoted K63 polyubiquitination of Bcl10, causing Bcl10 association with the autophagy adaptor p62. Paradoxically, p62 binding was required for both Bcl10 signaling to NF-kB and gradual degradation of Bcl10 by autophagy. Bcl10 autophagy was highly selective, as shown by the fact that it spared Malt1, a direct Bcl10 binding partner. Blockade of Bcl10 autophagy enhanced TCR activation of NF-kB. Together, these data demonstrate that selective autophagy of Bcl10 is a pathway-intrinsic homeostatic mechanism that modulates TCR signaling to NF-kB in effector T cells. This homeostatic process may protect T cells from adverse consequences of unrestrained NF-kB activation, such as cellular senescence.
Abstract. The observation and analyses of pre-seismic VLF electromagnetic (EM) signals recorded b... more Abstract. The observation and analyses of pre-seismic VLF electromagnetic (EM) signals recorded by VLF receivers at frequencies 5, 7, 9 and 12 kHz on November 16, 2008 over Kolkata (Lat. 22.56º N, Long. 88.5º E) during the large earthquake at Minahasa, Sulawesi, under ...
The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bul... more The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzymelinked immuno-sorbent assay. Before testing the herds, the farm managers were interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR = 3.6), human contacts (OR = 4.2), artificial insemination by other people than artificial insemination technicians (OR = 7.7), routine herd health contract with the veterinarian (OR = 4.3) and hygiene precautions taken by veterinarians (OR = 5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii.
In the presence of perturbations of the thermospheric auroral region produced by traveling ionosp... more In the presence of perturbations of the thermospheric auroral region produced by traveling ionospheric disturbances during the propagation of atmospheric gravity waves, an analytical expression of the velocity of the thermospheric plasma is derived through magnetohydrodynamic formalism. The expressions of the Joule heating and the viscous heating are derived, and their rates of variation are presented. A threshold height for their transition has been determined from their ratio, which is in agreement with the experimental data. The analysis indicates that the time taken by the thermospheric plasma to reach a steady-state corresponds to the nature of the traveling ionospheric disturbances in the medium.
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
Schumann resonances (SR) observations from a tropical region near Kolkata at the estuary of the r... more Schumann resonances (SR) observations from a tropical region near Kolkata at the estuary of the river Ganges merging into the Bay-of-Bengal (21.48° N, 88.61° E) are being made frequently. Several Q-bursts spectra are observed. Strong ELF transients are detected in the recorded data of SR. The dynamic evolution of electric and magnetic field components of the Q-bursts will be presented in this paper. Time series evolutions of signals of several Q-bursts are analyzed in the present study. It is observed that, the Q-burst amplitudes from 1 to 300 Hz of Qbursts spectra for 1 sec FFT reaches about-47 dB near the first mode of SR frequency. This shows that Q-burst has the tendency to dominate within 1 to 300 Hz.
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
Auroral electric field is a probable source of Atmospheric Gravity Waves (AGW) in the thermospher... more Auroral electric field is a probable source of Atmospheric Gravity Waves (AGW) in the thermospheric region of Auroral zone of the ionosphere and associated Traveling Ionospheric Disturbances (TID). This field is considered to be active through Lorentz force and Joule dissipation that influence the neutral gas of the medium through collision. The process introduces the short-range gravity waves. The expressions for the low frequency part of the fractional pressure variations have been derived within the auroral region of the ionosphere. The results of numerical analyses are presented graphically.
WKB method has been applied to solve some integral equations arising out of wave-particle interac... more WKB method has been applied to solve some integral equations arising out of wave-particle interaction within the upper atmosphere. Problem of ELF propagation through the Earth-Ionosphere waveguide has been investigated taking into account the inhomogeneities due to asymmetry of the day and night time ionosphere and variations of conductivity of the ionosphere. The results of numerical solutions are graphically presented through appropriate data and compared with previous results.
Well log data of thirty (30) boreholes from central part of Jharia coalfield have been analysed f... more Well log data of thirty (30) boreholes from central part of Jharia coalfield have been analysed for estimation of petrophysical and rock mechanical properties of coal seams to facilitate assessment of Coal Bed Methane (CBM) reservoir potentiality of those coal seam. Wells from Jharia area showed 18 major correlatable seams, intersected between 214 and 1324 m depth. The resistivity, density and natural gamma ray log data from the wells of the study area have been utilized for: (a) Estimation of permeability of coal seams from resistivity log data; (b) Computation of in-situ stress magnitudes—vertical stress, effective vertical stress and effective horizontal stress at seam horizons; (c) Establish relationship between in-situ stress and permeability; (d) Estimation of gas content of coal seams and identification of most potential zones for CBM exploration. It is observed that the permeability values ranging from 0.82 to 1.12 md with average gas content of 11.50 to 11.75 cc/gm. By comparing gas content, coal seam thickness as well as coal bed permeability of these major coal seams, the most viable CBM potential zone is mapped for this area.
Methods in molecular biology (Clifton, N.J.), 2015
T cells are an immune cell lineage that play a central role in protection against pathogen infect... more T cells are an immune cell lineage that play a central role in protection against pathogen infection. Antigen, in the form of pathogen-derived peptides, stimulates the T-cell receptor (TCR), leading to activation of the transcription factor, nuclear factor kappa B (NF-κB). The subsequent NF-κB-dependent gene expression program drives expansion and effector differentiation of antigen-specific T cells, leading to the adaptive anti-pathogen immune response. The cell surface TCR transmits activating signals to cytosolic NF-κB by a complex signaling cascade, in which the adapter protein Bcl10 plays a key role. We have previously demonstrated that TCR engagement leads to the formation of cytosolic Bcl10 clusters, called POLKADOTS, that provide a platform for the assembly of the terminal signaling complex that ultimately mediates NF-κB activation. In this chapter, we describe the methods utilized to visualize the formation of TCR-induced POLKADOTS and to study the temporal association betw...
Continuous recording of a subionospheric transmitted signal at 16.4 kHz from Novik, Norway (66°5 ... more Continuous recording of a subionospheric transmitted signal at 16.4 kHz from Novik, Norway (66°5 8´ N, 13° 54´ E) is being carried out in Kolkata (22° 34´ N, 88° 30´ E). The effects of recent solar eclipse on August 1, 2008 over this transmitted signal have been reported in this paper. The variations of normalized amplitude of this signal and its phase retardation in the path during the solar eclipse are measured which show significant deviations from their usual values for the same period of the control days.
The atmospheric radio noise field strength (ARNFS) at 700 Hz and 2100 Hz over Kolkata (Lat. 22.56... more The atmospheric radio noise field strength (ARNFS) at 700 Hz and 2100 Hz over Kolkata (Lat. 22.56 • N, Long. 88.5 • E) exhibits various characteristic patterns of diurnal and seasonal variations. Some distinctive features at these two frequencies have been observed in respect of the level of ARNFS during all the months, the fall of level from nighttime to daytime value, the correlation in sunrise time and the role of cloud activity upon the seasonal maximum. The outcome of analysis of the recorded data will be presented in this paper.
Antibodies to Coxiella burnetii have been found in the Danish dairy cattle population with high l... more Antibodies to Coxiella burnetii have been found in the Danish dairy cattle population with high levels of herd and within herd seroprevalences. However, the prevalence of antibodies to C. burnetii in Danish beef cattle remains unknown. The objectives of this study were to (1) estimate the prevalence and (2) identify risk factors associated with C. burnetii seropositivity in Danish beef and dairy cattle based on sampling at slaughter. Eight hundred blood samples from slaughtered cattle were collected from six Danish slaughter houses from August to October 2012 following a random sampling procedure. Blood samples were tested by a commercially available C. burnetii antibody ELISA kit. A sample was defined positive if the sample-to-positive ratio was greater than or equal to 40. Animal and herd information were extracted from the Danish Cattle Database. Apparent (AP) and true prevalences (TPs) specific for breed, breed groups, gender and herd type; and breed-specific true prevalences wi...
TCR-mediated activation of the transcription factor NF-κB is required for T cell proliferation, s... more TCR-mediated activation of the transcription factor NF-κB is required for T cell proliferation, survival, and effector differentiation. Although this pathway is the subject of intense study, it is not known whether TCR signaling to NF-κB is digital (switch-like) or analog in nature. Through analysis of the phosphorylation and degradation of IκBα and the nuclear translocation and phosphorylation of the NF-κB subunit RelA, we show that TCR-directed NF-κB activation is digital. Furthermore, digitization occurs well upstream of the IκB kinase complex, as protein kinase C θ translocation to the immunologic synapse and activation-associated aggregation of Bcl10 and Malt1 also demonstrate both digital behavior and high correlation with RelA nuclear translocation. Thus, similar to the TCR-to-MAPK signaling cascade, analog Ag inputs are converted to digital activation outputs to NF-κB at an early step downstream of TCR ligation.
Journal of Atmospheric and Solar-Terrestrial Physics, 2010
The variation of the first Schumann Resonance (SR) frequency spectra observed from the recorded d... more The variation of the first Schumann Resonance (SR) frequency spectra observed from the recorded data over Kolkata (22.56°N, 88.5°E) during a solar proton event (SPE) on July 14, 2000 has been presented. It shows increase in frequency during X-ray bursts and decrease during the ...
Accurate prediction of in-situ stress directions plays a key role in any Coal Bed Methane (CBM) e... more Accurate prediction of in-situ stress directions plays a key role in any Coal Bed Methane (CBM) exploration and exploitation project in order to estimate the production potential of the CBM reservoirs. Permeability is one of the most important factors for determination of CBM ...
The adaptor protein Bcl10 is a critically important mediator of T cell receptor (TCR)-to-NF-kB si... more The adaptor protein Bcl10 is a critically important mediator of T cell receptor (TCR)-to-NF-kB signaling. Bcl10 degradation is a poorly understood biological phenomenon suggested to reduce TCR activation of NF-kB. Here we have shown that TCR engagement triggers the degradation of Bcl10 in primary effector T cells but not in naive T cells. TCR engagement promoted K63 polyubiquitination of Bcl10, causing Bcl10 association with the autophagy adaptor p62. Paradoxically, p62 binding was required for both Bcl10 signaling to NF-kB and gradual degradation of Bcl10 by autophagy. Bcl10 autophagy was highly selective, as shown by the fact that it spared Malt1, a direct Bcl10 binding partner. Blockade of Bcl10 autophagy enhanced TCR activation of NF-kB. Together, these data demonstrate that selective autophagy of Bcl10 is a pathway-intrinsic homeostatic mechanism that modulates TCR signaling to NF-kB in effector T cells. This homeostatic process may protect T cells from adverse consequences of unrestrained NF-kB activation, such as cellular senescence.
Abstract. The observation and analyses of pre-seismic VLF electromagnetic (EM) signals recorded b... more Abstract. The observation and analyses of pre-seismic VLF electromagnetic (EM) signals recorded by VLF receivers at frequencies 5, 7, 9 and 12 kHz on November 16, 2008 over Kolkata (Lat. 22.56º N, Long. 88.5º E) during the large earthquake at Minahasa, Sulawesi, under ...
The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bul... more The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzymelinked immuno-sorbent assay. Before testing the herds, the farm managers were interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR = 3.6), human contacts (OR = 4.2), artificial insemination by other people than artificial insemination technicians (OR = 7.7), routine herd health contract with the veterinarian (OR = 4.3) and hygiene precautions taken by veterinarians (OR = 5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii.
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Papers by Suman Paul