Observation of non-equilibrium fluctuation in the shear-stress-driven hemoglobin aggregates.

Non-equilibrium fluctuations caused by the rearrangement of hemoglobin molecules into an aggregate state under shear stress have been investigated experimentally. The flow response under the shear stress (σ) corroborates the presence of contrasting aggregate and rejuvenation states governed by entropy production and consumption events. From the time-dependent shear rate fluctuation studies of aggregate states, the probability distribution function (PDF) of the rate of work done is observed to be spread from negative to positive values with a net positive mean. The PDFs follow the steady-state fluctuation theorem, even at a smaller timescale than that desired by the theorem. The behavior of the effective temperature (Teff) that emerges from a non-equilibrium fluctuation and interconnects with the structural restrictions of the aggregate state of our driven system is observed to be within the boundary of the thermodynamic uncertainty. The increase in Teff with the applied σ illustrates a phenomenal nonlinear power flux-dependent aggregating behavior in a classic bio-molecular-driven system.

Knowledge, Attitude and Level of Involvement of Married Males in Family Planning.

Background There is an age-old notion that family planning is women's responsibility disregarding the fact that men have equal responsibility in fertility regulation. Although male involvement is getting more recognition, studies on men's role in family planning are very few in the number in this part of the world. Objective To assess the knowledge, attitude and level of male involvement in family planning and to find out the factors associated with male involvement by contraceptive usage. Method A community based cross-sectional study was done from May to July 2021 among 165 currently married male, who had at least one child, living in Singur district of West Bengal. Cluster sampling method was done to select study participants and data were collected by pre-designed pretested questionnaire. Descriptive statistics, multivariable logistic regression was applied and data were analysed applying SPSS software. Result Only 36.4% participants were directly involved in family planning either by using condom or by withdrawal method but 65.5% participants were indirectly involved in family planning through spousal communication either by approving contraceptive use to their spouse or by decision making regarding family planning. Moreover, barrier of contraceptives usage were side effect (27%) and fear of impotence (25.5%). Male involvement was significantly associated with participant's education [AOR (95% CI= 3.63 (1.45-9.05)], caste [AOR (95% CI= 7.06 (2.55-19.51)], number of living children [AOR (95%CI= 5.01(1.95-12.87)], desire for more child [AOR (95% CI=0.34 (.13-.87)] and attitude on family planning [AOR (95% CI= 3.55 (1.41-8.94)]. Conclusion This study identified the prevailing gender norms in rural areas. Advocacy for male involvement in family planning by health personnel during counselling of eligible couples should help in increasing contraceptive coverage in the long run.

Advancement of Langmuir probe-based laser photo-detachment technique for negative ion density measurement in a high-power helicon plasma source.

In the pursuit of precise diagnostics for measuring negative ion density in a helicon plasma source (HPS), a new approach utilizing a radio frequency (RF) broadband transformer-based Langmuir probe is developed specifically for laser photo-detachment (LPD) analysis. This inductively coupled LPD technique is useful for high power RF systems in which capacitive RF noise is in the same scale as the pulsed photo-detachment signal. The signal acquired by this transformer-based probe is compared against the conventional Langmuir probe-based LPD technique, revealing a remarkable enhancement in signal fidelity through an improved signal-to-noise ratio (SNR) achieved by the RF broadband transformer methodology. In addition, the localized hydrogen negative ion density measurements obtained through this probe are harmoniously aligned with the line-averaged negative ion density derived from the cavity ringdown spectroscopy (CRDS) technique. These concurrence measurements highlight the RF broadband transformer-based approach's accuracy in capturing localized negative ion density during helicon mode operation in an HPS setup. Furthermore, the correlation of negative ion density values with RF input exhibits a consistent trend in tandem with background plasma density. Notably, both CRDS and LPD measurements ascertain negative ion densities ranging from ∼5 to 6×1016 m-3 under an RF power of 500-700 W and a pressure of 8 × 10-3 mbar, all under the influence of a 55 G axial magnetic field. These specific parameters represent the optimal operational configuration for effective negative ion production with the present experimental HPS setup. Due to its better SNR, the RF broadband transformer-based Langmuir probe emerges as a useful tool for LPD diagnostics, particularly in the presence of pervasive RF noise.

Overview of diagnostics on a small-scale RF source for fusion (ROBIN) and the one planned for the diagnostic beam for ITER.

India is responsible for the supply of diagnostic neutral beam systems for ITER to diagnose its helium ash during the deuterium-tritium plasma phase using the charge exchange recombination spectroscopy technique. Considering the many first of its kind in terms of technologies and beam development aspects, ITER Indian domestic agency has adopted a strategy of developing the technology and beam experimentation in parallel. On the beam development front three test beds, namely, the ROBIN (Rf Operated Beam source in India for Negative ion research), the TWIN (TWo rf driver-based Indigenously built Negative ion source), and the INTF (INdian Test Facility) are presently in their various phases of operation, optimization, and setting up at IPR, respectively. Experiments related to plasma production, beam production, and acceleration up to 30 keV in volume and surface mode have been performed on ROBIN. The maximum negative hydrogen ion current density to a tune of 27 mA/cm2 is obtained in the surface mode with Cs injection. Optimal source performance requires optimal surface conditions, minimum impurities, careful characterization of the plasma, cesium feed and its redistribution, and optimal wall temperatures of the surfaces of the plasma box and the plasma grid. A combination of probe, optical, vacuum, laser based, electrical, and calorimetric diagnostic measurements enables such a control. At ROBIN, the above diagnostics are being used regularly. The operational and diagnostic experiences on ROBIN shall provide the desired experience and database for operations of TWIN and INTF in the coming years. A large number of conventional and advanced diagnostic techniques are used for plasma and beam characterization. These diagnostics are suitable not only to detect and understand the plasma but also for studies related to impurity evolution. The temporal evolution of impurities significantly impacts the plasma and beam properties. The studies help in establishing correlations between physical parameters and operational parameters to optimize the source performance ensuring adequate safety and investment protection. This paper will present a brief overview of various diagnostics implemented, lessons learned, and the results obtained from ROBIN. In addition, an outline of the diagnostics planned for INTF based on the experience and understandings developed during the present experiments on ROBIN and TWIN and considering the requirements of large systems shall be discussed.

Quantification of atomic hydrogen anion density in a permanent magnet based helicon ion source (HELEN) by using pulsed ring down spectroscopy.

In the present work, a permanent magnet-based helicon plasma source (HELEN) is characterized as a negative ion source. A noninvasive diagnostic technique based on cavity ring down spectroscopy (CRDS) is developed to measure the line-integrated negative hydrogen ion (H-) density in HELEN. This paper discusses the experimental results in which negative hydrogen ion density is measured for different magnetic field, pressure, and RF (13.56 MHz) power configurations. It is observed that in high power range (800-850 W), the source is operating in helicon wave heating mode with a background plasma density of ∼1018 m-3 and electron temperature of ∼2 eV. Negative hydrogen ion density is measured by CRDS method and also by optical emission spectroscopic technique. The measured negative ion density is in the range of ∼1016 m-3 under volume mode operational condition even without any use of standard magnetic filter or cesium seeding in the downstream region. The influence of pressure variation (pressure range from 4 × 10-3 mbar to 4 × 10-2 mbar) on negative ion density production is not significant, except for a particular axial magnetic field configuration (55 G) and at 8 × 10-3 mbar pressure, where ∼34% hike is observed.

Plasma characterization of a microwave discharge ion source with mirror magnetic field configuration.

Microwave coupling to plasma through cavity dependent resonant modes is one of the key aspects in a microwave discharge ion source (MDIS) for improving the ion beam qualities as well as plasma dynamics. Knowing these concerns, a MDIS is designed, fabricated, and developed at Institute for Plasma Research to produce high current and a low emittance ion beam for accelerator applications. The present manuscript reports the development of MDIS and the characterization results of the first plasma produced by launching a microwave (MW) of frequency 2.45 GHz. The plasma is characterized at a particular distance away from the ion extraction aperture, using three diagnostics tools such as a Langmuir Probe (LP), Optical Emission Spectroscopy (OES), and a microwave spectrum analyzer. The required mirror-B magnetic field is created by placing four high power ring magnets (each magnet pole strength is 1.38 T) around the cylindrical source chamber. All diagnostics measurements are performed under an operating pressure of range 2 × 10-4-1 × 10-3 mbar and the plasma absorbed power of 30-160 W. The measured cold electron temperature and density varies in the range of ∼1.5-11.8 eV and 5.6 × 1016 m-3-6 × 1017 m-3, respectively, within the source volume. The electron population has distinct hot and cold plasma temperature. The hot electron temperature changes from ∼20 to 70 eV within the above absorbed power range. The LP and OES measurements witnessed the density jumps from under-dense (∼7.3 × 1016 m-3) to over-dense (∼2.9 × 1017 m-3) for the change in absorbed power from 50 W to 80 W. This density jump is accompanied by the sideband generation around the cavity resonant mode (including the launched MW) frequencies which range from 238 kHz to 873 kHz and is recognized as ion waves from the dispersion relation. The ion temperature, estimated from these observed low frequency instabilities, changes from 0.095 to 1.25 eV. The influences of these instabilities on beam emittance growth are of paramount importance in future studies.

Development and characterization of a helicon plasma source.

The Helicon Plasma Source (HeliPS) designed and developed at the Centre of Plasma Physics-Institute for Plasma Research is a versatile helicon plasma device, which operates in a wide range of magnetic field configurations from 50 G to 500 G. This device is dedicated to perform a broad range of research activities. The main objective for development of the HeliPS is to carry out studies on ion-ion plasmas in electronegative gases. In the near future, ion-ion plasmas will be formed in electronegative gases in the downstream of the plasma production region. Although the system is primarily designed to carry out ion-ion plasma experiments, the same system can also be used for experimental studies on some basic helicon plasma properties such as wave propagation, wave coupling, and plasma instability. At present, argon plasma is produced with a RF power supply of 13.56 MHz frequency. External circuit parameters, such as antenna current, plasma resistance (Rp), and internal parameters, such as electron density and temperature, are measured. The details of the experimental setup development, device characteristic, as well as preliminary plasma production and characterization to confirm occurrence of the helicon plasma in the system are presented in this article.

Performance evaluation of a permanent ring magnet based helicon plasma source for negative ion source research.

Helicon wave heated plasmas are much more efficient in terms of ionization per unit power consumed. A permanent magnet based compact helicon wave heated plasma source is developed in the Institute for Plasma Research, after carefully optimizing the geometry, the frequency of the RF power, and the magnetic field conditions. The HELicon Experiment for Negative ion-I source is the single driver helicon plasma source that is being studied for the development of a large sized, multi-driver negative hydrogen ion source. In this paper, the details about the single driver machine and the results from the characterization of the device are presented. A parametric study at different pressures and magnetic field values using a 13.56 MHz RF source has been carried out in argon plasma, as an initial step towards source characterization. A theoretical model is also presented for the particle and power balance in the plasma. The ambipolar diffusion process taking place in a magnetized helicon plasma is also discussed.

Development of a novel surface assisted volume negative hydrogen ion source.

H- ion based neutral beam injector is a critical heating and current drive system in a fusion reactor. However, the present H- ion source configuration has limitations in terms of production, extraction, cesium (Cs) inventory and management. To overcome these limitations, a proof-of-principle experiment based on a novel concept regarding surface assisted volume H- ions production by sprinkling Cs coated tungsten (W) dust grains (low work function surface) into a hydrogen plasma is carried out. Four different diagnostics have been used to validate the concept. The H- ion fraction is estimated from (a) Langmuir probe diagnostic, (b) phase velocity of ion acoustic waves, (c) dust current and confirmed by the measurement of (d) Balmer line ratio. The measured H- ion fraction with respect to the plasma density for different discharge conditions varies from ~0.2 to 0.3 in presence of Cs coated W dust particles. The experimental results show good agreement with the theoretical estimation.

Physics-electrical hybrid model for real time impedance matching and remote plasma characterization in RF plasma sources.

Plasma characterization and impedance matching are an integral part of any radio frequency (RF) based plasma source. In long pulse operation, particularly in high power operation where plasma load may vary due to different reasons (e.g. pressure and power), online tuning of impedance matching circuit and remote plasma density estimation are very useful. In some cases, due to remote interfaces, radio activation and, due to maintenance issues, power probes are not allowed to be incorporated in the ion source design for plasma characterization. Therefore, for characterization and impedance matching, more remote schemes are envisaged. Two such schemes by the same authors are suggested in these regards, which are based on air core transformer model of inductive coupled plasma (ICP) [M. Bandyopadhyay et al., Nucl. Fusion 55, 033017 (2015); D. Sudhir et al., Rev. Sci. Instrum. 85, 013510 (2014)]. However, the influence of the RF field interaction with the plasma to determine its impedance, a physics code HELIC [D. Arnush, Phys. Plasmas 7, 3042 (2000)] is coupled with the transformer model. This model can be useful for both types of RF sources, i.e., ICP and helicon sources.

Overview of ion source characterization diagnostics in INTF.

INdian Test Facility (INTF) is envisaged to characterize ITER diagnostic neutral beam system and to establish the functionality of its eight inductively coupled RF plasma driver based negative hydrogen ion source and its beamline components. The beam quality mainly depends on the ion source performance and therefore, its diagnostics plays an important role for its safe and optimized operation. A number of diagnostics are planned in INTF to characterize the ion source performance. Negative ions and its cesium contents in the source will be monitored by optical emission spectroscopy (OES) and cavity ring down spectroscopy. Plasma near the extraction region will be studied using standard electrostatic probes. The beam divergence and negative ion stripping losses are planned to be measured using Doppler shift spectroscopy. During initial phase of ion beam characterization, carbon fiber composite based infrared imaging diagnostics will be used. Safe operation of the beam will be ensured by using standard thermocouples and electrical voltage-current measurement sensors. A novel concept, based on plasma density dependent plasma impedance measurement using RF electrical impedance matching parameters to characterize the RF driver plasma, will be tested in INTF and will be validated with OES data. The paper will discuss about the overview of the complete INTF diagnostics including its present status of procurement, experimentation, interface with mechanical systems in INTF, and integration with INTF data acquisition and control systems.

Reduction of copper in porous matrixes. Stepwise and autocatalytic reduction routes.

The reduction of Cu(II) oxide species in siliceous matrixes of different porosity (MFI, FAU, MCM-48) and in alumosilicate MFI was studied by temperature-programmed reduction in hydrogen (TPR), by X-ray absorption fine structure (after stationary hydrogen treatments), and by transmission electron microscopy. It was found that the reduction may proceed in one or in two reduction steps. The two-step scheme known for zeolites was observed also for Cu(II) in siliceous microporous matrixes, with similar temperature of Cu(II) reduction onset as for the alumosilicate MFI. Therefore, the two-step scheme cannot be explained by the stabilization of Cu ions by intra-zeolite electrical fields. CuOx clusters in MCM-48 were reduced in a one-step scheme (similar to bulk CuO) at high Cu content (6 wt %) but in a two-step scheme at low Cu content (1 wt %). The two reduction steps observed with most samples cannot be identified with the transitions of all Cu(II) to Cu(I) and of Cu(I) to Cu(0). Instead, Cu(0) nuclei were observed already at low reduction temperatures and were found to coexist with Cu ions over temperature ranges of different extension. This coexistence range was narrow in materials that favor aggregation of the Cu nuclei into particles: Cu-MCM-48 of low Cu content and Cu-ZSM-5. In the latter, metal segregation from the pore system was found to be accompanied by an autocatalytic initiation of the second reduction step. In the siliceous microporous matrixes, the Cu(0) nuclei were observed to coexist with Cu ions over wide temperature ranges (100 K for MFI) at temperatures far above that of Cu reduction in the bulk oxide. These observations suggest that oligomeric Cu metal nuclei which may have been formed, e.g., at the intersections of the MFI channel system, may be unable to activate hydrogen, which would be required for rapid reduction of the coexisting Cu ions.

A population based survey of the prevalence and types of glaucoma in rural West Bengal: the West Bengal Glaucoma Study.

AIM: To determine (i) the prevalence of glaucoma in people aged > or =50 years, (ii) the proportions of different types of glaucoma, (iii) the distributions of intraocular pressure and vertical cup disc ratio. METHOD: Population based prevalence survey in rural West Bengal. People aged > or =50 years in randomly selected villages in 24 Parganas South district. The main outcome measures were diagnosis of glaucoma, based on criteria described by the International Society for Geographic and Epidemiological Ophthalmology. RESULTS: 1594 people aged > or =50 years were enumerated in nine villages; 1324 (83.1%) were surveyed and 1269 people adequately examined. 42 definite cases of glaucoma were identified, with prevalence increasing from 2.7% (95% CI 1.7 to 3.7) in people aged 50-59 years to 6.5% (95% CI 0.0 to 14.1) in those aged > or =80 years. The age standardised estimate for the prevalence of all glaucoma in people aged > or =50 years was 3.4%. Only three cases of primary angle closure glaucoma (PACG) were identified, giving a crude ratio of primary open angle glaucoma (POAG) to PACG of more than 10:1. Three people with glaucoma were blind in one eye but none was blind in both eyes. CONCLUSION: Compared to other surveys of glaucoma in India, the age standardised prevalence observed was less than in Hyderabad, but similar to Tamil Nadu and Dhaka. The ratio of POAG to PACG was much higher than found previously, suggesting that PACG may be less prevalent in Bengalis than in Indian populations living in south India. The authors conclude that ophthalmic services in West Bengal should focus on detecting POAG. Since there is still no satisfactory method of screening for POAG, there is no alternative to case detection (opportunistic screening) in eye clinics.

Iron store and free radicals in thalassemia.

Hyper-ferrous state is the result of multiple transfusions, whereby the iron excess in such conditions may be toxic to the organism. Patients suffering from thalassemia receive multiple transfusions. In the eastern part of India, both ß(0)-thalassemia and heterozygous Eß-thalassemia occur. This paper expresses the hyper-ferrous state, leading to iron overload in these two conditions and also reports the increased generation of free radicals, consequent to the iron overload.

Monoamineoxidase activity in certain brain regions associated with xanthurenic acid excretion in rats on oral contraceptive steroids.

Monoamineoxidase (MAO) activity in some regions of brain and urinary xanthurenic acid were investigated in female rats administered with oral contraceptive (OC) steroids-ethynyl estradiol (Ees), lynestrenol (Ly) and both in combination (Cm) for 75 days. The MAO activity was reduced significantly in most regions specially in cortex-the extent of reduction being 65 per cent with Ees, 51 per cent with Ly and 69 per cent with Cm treatments. In the hypothalamus, the activity was decreased by 50 per cent with Ees, 38 per cent with Ly and by 40 per cent with Cm treatments. In the corpus striatum the activity was reduced by 14 per cent with Ly treatment, 25 per cent with Cm treatment and in the midbrain by 59 per cent with Ees treatment only. The concentration of xanthurenic acid in urine was higher by 55 per cent with Ees, 109 per cent with Ly and by 120 per cent with Cm treatments. These changes in MAO activity and level of xanthurenic acid excretion indicate the possible alteration in the metabolism of neurotransmitter, associated with prolonged use of OC.

A design of a vermiculite column adsorber for the removal of lead from water.

Mini-column techniques were employed to determine the mass transfer coefficient for lead adsorption onto vermiculite. Variation of the mass transfer coefficient with flow rate, particle size of sorbent, and influent lead concentration were studied. Multiple linear regression (MLR) analysis showed that the mass transfer coefficient varied as the 0.43 power of the liquid flow rate and inversely as the 0.272 power of particle diameter of the vermiculite, but was independent of the influent concentration of lead. Different parameters of a fixed bed column design for the removal of lead by vermiculite were determined using the data from the batch sorption study. The performance of the liquid bed column in removing lead was in close agreement with predicted performance using the batch isotherm data.

Purification of pulp and paper mill effluent using Eichornia crassipes.

Konark Pulp and Paper Industries Private Limited is a medium size industry producing 1600 m3 of wastewater a day. The existing water treatment system of the industry was found to be ineffective both in performance and economy. In the present study, a new system of treatment has been developed using water hyacinth Eichornia crassipes, coagulation by lime and alum, followed by rapid sand filtration. The performance efficiency of each unit viz. Eichornia treatment; coagulation with lime, with alum, and with lime:alum combinations, and filtration was studied. Water quality parameters considered were Biological Oxygen Demand, Chemical Oxygen Demand, Dissolve Oxygen, Total Dissolved Solids, turbidity, percentage transmission, and water colour. Based on the individual performance of each unit, a continuous system has been designed and was tested. The new system of treatment could treat the wastewater to the discharge standards and also was found economically feasible. Testing culture of fish (tilapia) proved that the treated water could be safely discharged into natural waters. All fish tested, survived and remained healthy throughout the period of testing. Culture of fish further improved the water quality.

Online tuning of impedance matching circuit for long pulse inductively coupled plasma source operation--an alternate approach.

Impedance matching circuit between radio frequency (RF) generator and the plasma load, placed between them, determines the RF power transfer from RF generator to the plasma load. The impedance of plasma load depends on the plasma parameters through skin depth and plasma conductivity or resistivity. Therefore, for long pulse operation of inductively coupled plasmas, particularly for high power (∼100 kW or more) where plasma load condition may vary due to different reasons (e.g., pressure, power, and thermal), online tuning of impedance matching circuit is necessary through feedback. In fusion grade ion source operation, such online methodology through feedback is not present but offline remote tuning by adjusting the matching circuit capacitors and tuning the driving frequency of the RF generator between the ion source operation pulses is envisaged. The present model is an approach for remote impedance tuning methodology for long pulse operation and corresponding online impedance matching algorithm based on RF coil antenna current measurement or coil antenna calorimetric measurement may be useful in this regard.

Optimization of negative ion current in a compact microwave driven upper hybrid resonance multicusp plasma source.

Performance of a microwave driven upper hybrid resonance multicusp plasma source as a volume negative ion source is reported. Microwaves are directly launched into the plasma chamber predominantly in the TE(11) mode. The source is operated at different discharge conditions to obtain the optimized negative H(-) ion current which is ∼33 µA (0.26 mA∕cm(2)). Particle balance equations are solved to estimate the negative ion density, which is compared with the experimental results. Future prospects of the source are discussed.

A study of obliquity of femoral shaft in Eastern Indian population.

In the erect posture, femur is not absolute vertical, being separated above from its fellow by a considerable interval, which corresponds to the breadth of the pelvis, and inclines gradually medially and downward, so as to approach its fellow, for the purpose of bringing the knee joints near the line of gravity of the body. In the present study obliquity of femoral shaft measured in 127 dry femora. Mean obliquity of femoral shaft for 62 left sided femora found 8.431 degrees with standard deviation of 2.361 degrees whereas for 65 right sided femora were found to be 7.708 degrees with standard deviation of 2.425 degrees. When total 127 femora considered, mean bicondylar angle of 8.061 +/- 2.412 degrees was obtained. Though statistically insignificant, mean bicondylar angle determined on left side was higher than that on the right side.