Measurement of energy and directional distribution of neutron ambient dose equivalent for the 7Li(p,n)7Be reaction

Double differential neutron fluence distributions were measured in the 7Li(p,n)7Be reaction for proton beam energies 7, 9 and 12 MeV. Seven liquid scintillator based detectors were employed to measure neutron fluence distributions using the Time of Flight technique. Neutron ambient dose equivalents were determined from the measured fluence distribution using ICRP (International Commission on Radiological Protection) recommended fluence to dose equivalent conversion coefficients. Neutron dose equivalents were also measured using a conventional BF3 detector based REM counter. Ambient dose equivalent measured by the REM counter is found to be in agreement with that determined from the neutron fluence spectra within their uncertainties. Angular distributions of the ambient dose equivalents were also determined from the measured fluence distributions at different angles.

Early arrivals: association of maternal obstetric factors with preterm births and their survival in India

OBJECTIVES

Preterm birth (PTB) increases the risk of various acute and chronic morbidities and premature mortality in children under 5 years of age. The present study examines the association between different maternal obstetric factors and PTB. In addition, this study estimates the risk of neonatal mortality among children born preterm.

STUDY DESIGN

Retrospective two-stage stratified sample design.

METHODS

The weighted prevalence of PTB was estimated using data on 148,746 most recent institutional births from the National Family Health Survey (NFHS)-4, 2015-16. The Poisson regression model was used to investigate the association between maternal obstetric factors and PTB. Using Cox's proportional hazard model, the risk of neonatal mortality among PTBs was estimated.

RESULTS

Maternal obstetric factors, such as minimal antenatal care, delivery complications, history of previous caesarean delivery and delivery at private health facilities, were significantly associated with an increased risk of PTB. The survival probability of preterm babies sharply declined in the first week of life and thereafter was found to stabilise. The risk of mortality in the first 28 days of life increased 2.5-fold if the baby was born preterm. Optimising antenatal care was found to lower the likelihood of PTB and improve their chances of survival.

CONCLUSION

Antenatal care services and delivery care practices in private facilities were strongly associated with the incidence and survival of PTB. Evaluating associations of history of caesarean births on future pregnancies can help understand their deleterious effects on PTB. Affordable, accessible and available antenatal care services, in both public and private facilities, can increase the survival rates of PTBs.

P–391 Role of subcutaneous granulocyte colony-stimulating factor infusion in thin endometrium

Study question

To assess the role of subcutaneous granulocyte colony-stimulating factor (G-CSF) in thin endometrium cases.

Summary answer

G CSF has beneficial role to improve the endometrium thickness in thin endometrium.

What is known already

Endometrium is very important for embryo implantation and the endometrial thickness is the marker of receptivity of the endometrium.

Study design, size, duration

Study design - Retrospective analysis

Size - 88 infertile females with thin endometrium (< 7 mm) in the age group of 23 to 40 years Duration - one year.

Participants/materials, setting, methods

In the group 1 of 44 females, subcutaneous infusion of G CSF (300 mcg/ml) was added along with other supplements and if lining was not more than 7 mm in 72 hours, then second infusion was given. In the group 2 of 44 females, only estradiol valerate and sildenafil were given.The efficacy of G CSF was evaluated by assessing the endometrium thickness before embryo transfer, pregnancy rates and clinical pregnancy rates.

Main results and the role of chance

There was no difference between the two groups regarding demographic variables, egg reserve, sperm parameters, number of embryos transferred and embryo quality. . The pregnancy rate was 60% (24 out of 40 cases) in the group 1 that was significantly higher than in-group 2 that was 31% (9 out of 29 cases) with p value < 0.0001. The clinical pregnancy rate was also significantly higher in-group 1 (55%) as compared to group 2 (24%) with p value < 0.0001.

Limitations, reasons for caution

Further larger cohort studies are required to explore the subcutaneous role of G CSF in thin endometrium.

Wider implications of the findings: Granulocyte colony-stimulating factor has beneficial role to improve the endometrium thickness in thin endometrium. In most of previous studies, the intrauterine infusion of G CSF was given to improve the uterine lining. This is one of the few studies done that showed subcutaneous role of G CSF in thin endometrium.

Trial registration number

Not applicable

Pro-poor policies and improvements in maternal health outcomes in India

BACKGROUND

Since 2005, India has experienced an impressive 77% reduction in maternal mortality compared to the global average of 43%. What explains this impressive performance in terms of reduction in maternal mortality and improvement in maternal health outcomes? This paper evaluates the effect of household wealth status on maternal mortality in India, and also separates out the performance of the Empowered Action Group (EAG) states and the Southern states of India. The results are discussed in the light of various pro-poor programmes and policies designed to reduce maternal mortality and the existing supply side gaps in the healthcare system of India. Using multiple sources of data, this study aims to understand the trends in maternal mortality (1997-2017) between EAG and non EAG states in India and explore various household, economic and policy factors that may explain reduction in maternal mortality and improvement in maternal health outcomes in India.

METHODS

This study triangulates data from different rounds of Sample Registration Systems to assess the trend in maternal mortality in India. It further analysed the National Family Health Surveys (NFHS). NFHS-4, 2015-16 has gathered information on maternal mortality and pregnancy-related deaths from 601,509 households. Using logistic regression, we estimate the association of various socio-economic variables on maternal deaths in the various states of India.

RESULTS

On an average, wealth status of the households did not have a statistically significant association with maternal mortality in India. However, our disaggregate analysis reveals, the gains in terms of maternal mortality have been unevenly distributed. Although the rich-poor gap in maternal mortality has reduced in EAG states such as Bihar, Odisha, Assam, Rajasthan, the maternal mortality has remained above the national average for many of these states. The EAG states also experience supply side shortfalls in terms of availability of PHC and PHC doctors; and availability of specialist doctors.

CONCLUSIONS

The novel contribution of the present paper is that the association of household wealth status and place of residence with maternal mortality is statistically not significant implying financial barriers to access maternal health services have been minimised. This result, and India's impressive performance with respect to maternal health outcomes, can be attributed to the various pro-poor policies and cash incentive schemes successfully launched in recent years. Community-level involvement with pivotal role played by community health workers has been one of the major reasons for the success of many ongoing policies. Policy makers need to prioritise the underperforming states and socio-economic groups within the states by addressing both demand-side and supply-side measures simultaneously mediated by contextual factors.

Aberrant CREB1 activation in prostate cancer disrupts normal prostate luminal cell differentiation

The molecular mechanisms of luminal cell differentiation are not understood well enough to determine how differentiation goes awry during oncogenesis. Using RNA-Seq analysis, we discovered that CREB1 plays a central role in maintaining new luminal cell survival and that oncogenesis dramatically changes the CREB1-induced transcriptome. CREB1 is active in luminal cells, but not basal cells. We identified ING4 and its E3 ligase, JFK, as CREB1 transcriptional targets in luminal cells. During luminal cell differentiation, transient induction of ING4 expression is followed by a peak in CREB1 activity, while JFK increases concomitantly with CREB1 activation. Transient expression of ING4 is required for luminal cell induction; however, failure to properly down-regulate ING4 leads to luminal cell death. Consequently, blocking CREB1 increased ING4 expression, suppressed JFK, and led to luminal cell death. Thus, CREB1 is responsible for the suppression of ING4 required for luminal cell survival and maintenance. Oncogenic transformation by suppressing PTEN resulted in constitutive activation of CREB1. However, the tumor cells could no longer fully differentiate into luminal cells, failed to express ING4, and displayed a unique CREB1 transcriptome. Blocking CREB1 in tumorigenic cells suppressed tumor growth in vivo, rescued ING4 expression, and restored luminal cell formation, but ultimately induced luminal cell death. IHC of primary prostate tumors demonstrated a strong correlation between loss of ING4 and loss of PTEN. This is the first study to define a molecular mechanism whereby oncogenic loss of PTEN, leading to aberrant CREB1 activation, suppresses ING4 expression causing disruption of luminal cell differentiation.

An epidemic of avoidable caesarean deliveries in the private sector in India: Is physician-induced demand at play?

PURPOSE AND SETTING OF RESEARCH

Caesarean section (C-section) rates of over 15% suggest overuse of the surgery which may be difficult to justify on medical grounds. One important contributor to the rise in Csection rates is the rapid expansion of unregulated private-sector providers in number of settings. This study analyses the contribution of private sector in the rapid rise in Csection deliveries in India and the extent to which these can be justified on medical grounds.

METHODS

This is a cross sectional study design using National Family Health Surveys. Logistic regression and propensity score matching (PSM) analyses are performed. The main outcome measured is avoidable C-sections in the private sector.

PRINCIPAL FINDINGS

Our findings suggest that the rising trend in C-section rates in the private sector cannot be explained by medical reasons alone. The odds of C-section among women who chose to deliver in private was over 4 times higher than women who chose to delivery in public facilities. Despite, controlling for medical complications, women's characteristics and preferences, our PSM analysis suggest that the public-private gap has doubled over the years and that the difference cannot be explained by known determinants of C-section. Over supply of avoidable C-section to the extent of 21%, as a result of physician induced demand and perverse financial incentives was observed in the private sector.

CONCLUSIONS

This paper attempts to understand the reason for the high C-section rates in the private sector in India and the extent to which these are avoidable. Our analysis supports the assumption that physician induced demand as a result of perverse financial incentives in the private sector is at play.

Extended field-of-view adaptive optics in microscopy via numerical field segmentation

Sample-induced optical aberrations in microscopy are, in general, field dependent, limiting their correction via pupil adaptive optics (AO) to the center of the available field-of-view (FoV). This is a major hindrance, particularly for deep tissue imaging, where AO has a significant impact. We present a new wide-field AO microscopy scheme, in which the deformable element is located at the pupil plane of the objective. To maintain high-quality correction across its entirety, the FoV is partitioned into small segments, and a separate aberration estimation is performed for each via a modal-decomposition-based indirect wavefront sensing algorithm. A final full-field image is synthesized by stitching of the partitions corrected consecutively and independently via their respective measured aberrations. The performance and limitations of the method are experimentally explored on synthetic samples imaged via a custom-developed AO fluorescence microscope featuring an optofluidic refractive wavefront modulator.

Fully refractive adaptive optics fluorescence microscope using an optofluidic wavefront modulator

Adaptive optics (AO) represents a powerful range of image correction technologies with proven benefits for many life-science microscopy methods. However, the complexity of adding a reflective wavefront modulator and in some cases a wavefront sensor into an already complicated microscope has made AO prohibitive for its widespread adaptation in microscopy systems. We present here the design and performance of a compact fluorescence microscope using a fully refractive optofluidic wavefront modulator, yielding imaging performance on par with that of conventional deformable mirrors, both in correction fidelity and articulation. We combine this device with a modal sensorless wavefront estimation algorithm that uses spatial frequency content of acquired images as a quality metric and thereby demonstrate a completely in-line adaptive optics microscope that can perform aberration correction up to 4^th radial order of Zernike modes. This entirely new concept for adaptive optics microscopy may prove to extend the performance limits and widespread applicability of AO in life-science imaging.

Elastic Scattering and Reaction Cross-section of 8Li on 209Bi

Nuclear physics in the 21st century is driven by a quest to understand the properties of ever more exotic nuclear systems. Unusual structural phenom- ena are observed to arise in light weakly bound nuclei such as 8Li. 8Li has a cluster structure core of 7Li surrounded by a loosely bound neutron which is observed to influence reaction mechanisms near the fusion barrier. Elastic scat- tering provides a vital step towards understanding more complicated reaction mechanisms. In this work, elastic scattering was measured for 8Li + 2°9Bi at energies 2% to 34% above the barrier, allowing extraction of reaction cross- sections. The systematics of the reaction cross-sections of 8Li compared to neighbouring nuclei 6,7,9,11Li are discussed.

Mechanisms Suppressing Superheavy Element Yields in Cold Fusion Reactions

Superheavy elements are formed in fusion reactions which are hindered by fast nonequilibrium processes. To quantify these, mass-angle distributions and cross sections have been measured, at beam energies from below-barrier to 25% above, for the reactions of ^{48}Ca, ^{50}Ti, and ^{54}Cr with ^{208}Pb. Moving from ^{48}Ca to ^{54}Cr leads to a drastic fall in the symmetric fission yield, which is reflected in the measured mass-angle distribution by the presence of competing fast nonequilibrium deep inelastic and quasifission processes. These are responsible for reduction of the compound nucleus formation probablity P_{CN} (as measured by the symmetric-peaked fission cross section), by a factor of 2.5 for ^{50}Ti and 15 for ^{54}Cr in comparison to ^{48}Ca. The energy dependence of P_{CN} indicates that cold fusion reactions (involving ^{208}Pb) are not driven by a diffusion process.

Successful switch (tOPV to bOPV) in India: Tribute to a resilient health system

In accordance with the end game strategies for polio eradication a synchronized switch plan from tOPV to bOPV was implemented globally in 2016. The National Committee for Polio Eradication (NCCPE) validated the switch activities in India. An expert group of 104 academics conducted field visits in 25 states and 2 Union territories for independent verification (after an initial round of verification by the National Polio Surveillance Project [NPSP]). The objectives were to validate withdrawal and disposal of tOPV by screening cold chain points in public and private sector health facilities in both rural and urban areas; additionally, availability of bOPV and IPV was also documented. 34 filled tOPV and 5 empty vials were detected inside cold chain equipment and 17 outside. The disposal mechanism was found to be reasonably adequate. The key strategies -- 'throttling' of vaccine supplies well ahead of the switch date while preventing stock outs at various immunization points, simultaneously working with the regulators to delicense the tOPV on the switch date and helping manufacturers to calibrate vaccine production according to national timelines, and strong and persistent advocacy with professional associations to align with national bOPV and IPV policy facilitated successful accomplishment of the switch process. Effective implementation of the switch strategy in India also bears testimony to the resilience of the health system operating under diverse and heterogeneous governance.

Origins of Incomplete Fusion Products and the Suppression of Complete Fusion in Reactions of ^{7}Li

Above-barrier complete fusion involving nuclides with low binding energy is typically suppressed by 30%. The mechanism that causes this suppression, and produces the associated incomplete fusion products, is controversial. We have developed a new experimental approach to investigate the mechanisms that produce incomplete fusion products, combining singles and coincidence measurements of light fragments and heavy residues in ^{7}Li+^{209}Bi reactions. For polonium isotopes, the dominant incomplete fusion product, only a small fraction can be explained by projectile breakup followed by capture: the dominant mechanism is triton cluster transfer. Suppression of complete fusion is therefore primarily a consequence of clustering in weakly bound nuclei rather than their breakup prior to reaching the fusion barrier. This implies that suppression of complete fusion will occur in reactions of nuclides where strong clustering is present.

Optimization-based real-time open-loop control of an optofluidic refractive phase modulator

We present a novel open-loop control method for an electrostatically actuated optofluidic refractive phase modulator, and demonstrate its performance for high-order aberration correction. Contrary to conventional electrostatic deformable mirrors, an optofluidic modulator is capable of bidirectional (push-pull) actuation through hydro-mechanical coupling. Control methods based on matrix pseudo-inversion, the common approach used for deformable mirrors, thus perform sub-optimally for such a device. Instead, we formulate the task of finding driving voltages for a given desired wavefront shape as an optimization problem with inequality constraints that can be solved using an interior-point method in real time. We show that this optimization problem is a convex one and that its solution represents a global minimum in residual wavefront error. We use the new method to control both the refractive phase modulator and a conventional electrostatic deformable mirror, and experimentally demonstrate improved correction fidelity for both.

Optofluidic adaptive optics

We introduce a transmissive refractive adaptive optics system featuring a deformable transparent optofluidic wavefront modulator and a sensorless wavefront error estimation algorithm. The wavefront modulator consists of a cavity filled with an optical liquid which is sealed by a deformable elastic polymer membrane. Deformation of the membrane is achieved through electrostatic actuation using 25 transparent indium tin oxide electrodes buried in the cavity. Modulation of the two-dimensional phase distribution generated by the system is performed using open loop control both with and without active wavefront sensing. For the latter, a progressive modal decomposition algorithm is used to estimate and correct distortion in the point-spread function (PSF) of the wavefront arising due to the optical system and other sources of wavefront distortion. Using this control method, we experimentally demonstrate high-fidelity recreation of Zernike modes up to the fourth order, and blind (sensorless) PSF correction in a wide-field microscope.

Optimization of beam dump shielding for K-130 cyclotron at VECC

A compact and efficient beam dump shield has been designed using Monte Carlo simulation code FLUKA to facilitate low background measurement of neutron and gamma rays using K130 cyclotron at Variable Energy Cyclotron Centre, Kolkata (VECC). Iron, lead and high density Polyethylene (HDPE) were considered in the design of the beam dump shield. Representative FLUKA simulation results have been validated using in-beam experiment performed on the same beam dump constituents. Experimental neutron and gamma-rays energy spectra have been found to be in fair agreement with the simulation results. Activation of various beam dump shield components were also carried out.

Experimental Determination of η/s for Finite Nuclear Matter

We present, for the first time, simultaneous determination of shear viscosity (η) and entropy density (s) and thus, η/s for equilibrated nuclear systems from A∼30 to A∼208 at different temperatures. At finite temperature, η is estimated by utilizing the γ decay of the isovector giant dipole resonance populated via fusion evaporation reaction, while s is evaluated from the nuclear level density parameter (a) and nuclear temperature (T), determined precisely by the simultaneous measurements of the evaporated neutron energy spectra and the compound nuclear angular momenta. The transport parameter η and the thermodynamic parameter s both increase with temperature, resulting in a mild decrease of η/s with temperature. The extracted η/s is also found to be independent of the neutron-proton asymmetry at a given temperature. Interestingly, the measured η/s values are comparable to that of the high-temperature quark-gluon plasma, pointing towards the fact that strong fluidity may be the universal feature of the strong interaction of many-body quantum systems.