Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970–2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND: Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016. METHODS: We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone. FINDINGS: Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, an

Study of particle transport in a high power spallation target for an accelerator driven transmutation system

Transmutation of highly radioactive nuclear waste can be performed using an accelerator driven system (ADS), where high energy protons impinge on a spallation target to produce neutrons. These neutrons are multiplied in a subcritical core, while simultaneously fissioning the minor actinides into short lived or stable nuclides. AGATE is a project envisaged to demonstrate the feasibility of transmutation in a gas (helium) cooled ADS using solid spallation target. Development of the spallation target module and assessing its safety aspects are studied in this work. According to the AGATE concept parameters, 600 MeV protons are delivered on to the segmented tungsten spallation target. Tungsten is an ideal solid spallation target material because of its high melting point, other than the many desirable properties. Spallation is by far the most attractive means of neutron production when it comes to energy deposition per neutron. The spallation mechanism initiates with intranuclear cascade (INC) reactions, followed by deexcitation of nuclei through evaporation, multifragmentation and fission. Both the INC and deexcitation processes lead to the production of neutrons and spallation products. Spallation neutron energy spectrum is relatively harder compared to fission because of the higher energetics involved. The monte carlo toolkit Geant4 has been used in the simulation of particle transport. From the systematics study of incident projectile types (proton, deuteron and alpha), neutron yield due to proton and deuteron are generally higher than that for alpha. At higher energies, deuteron fares better than proton. Given the lower kinetic energy of proton (600 MeV) and owing to the fact that acceleration cost increases with increasing mass, proton turns out to be the ideal projectile for the current system. Energy cost of neutron production is the most efficient for protons of energy between 800 and 1000 MeV. Nuclear collision probability increases with increasing proton energy, reaching a saturation value at about 1 GeV for tungsten. To ensure maximum interaction, the target length needs to be as long as the range of protons in the material. For 600 MeV protons, the range is about 15 cm in tungsten. There exists an optimum radius of the target determining the neutron yield. While lower radii means the leakage of energetic secondaries without producing further neutrons, larger radii results in the parasitic absorption. For tungsten, target radius of about 10 cm turns out to be a good option. In a monolith tungsten target, neutron buildup near the target head is not very suitable to illuminate the subcritical core coupled to the target. Hence splitting the target using fluxtraps into segments of varying thicknesses is necessary to produce a homogenized neutron field. This also leads to the hardening of the emitted neutron energy spectrum required for transmutation. Further, the fluxtraps allow efficient cooling and reduced parasitic absorption in the target. Power density in the optimized target is still very high to be cooled. Fluidizing the target with pebbles instead of solid material is a feasible option. Radiation damage has been calculated using the NRT theory for one full power year operation and per mA proton current. Damage is significant in the first few segments of the target, decreasing gradually with increasing tungsten length. Maximum damage in the target is inflicted on the first segment, about 4.5 dpa and the total damage is about 53 dpa. Total specific activity in the target at shutdown after one full power year operation is about 2.4E14 MBq/g per mA. Unlike the actinides, which need to be transmuted, radionuclides produced in the target are less radiotoxic and have shorter life time. Spallation produces high energy neutrons and gammas which need to be shielded. An additional dimension in the shielding calculation is introduced by the high energy forward peaked neutrons. Shields composed of boronated steel and boronated concrete are used, which greatly reduces the shielding dimensions while exhibiting good shielding performance. This also reduces the amount of activated materials. An inner thick layer of iron is required to attenuate the high energy of neutrons. The concrete block following this is efficient in shielding against the low energy neutrons

Effect of Target Configuration on the Neutronic Performance of the Gas-Cooled ADS

With the utilization of nuclear energy transuranic elements like Pu, Am and Cm are produced causing high, long term radioactivity and radio toxicity, respectively. To reduce the radiological impact on the environment and to the repository Partitioning and Transmutation is considered as an efficient way. In this respect comprehensive research works are performed at different research institutes worldwide. The results show that the transmutation of TRU is achieved with fast neutrons due to the higher fission probability. Based on Accelerator Driven Systems (ADS) those neutrons are used in a particular system, in which mainly liquid metal eutectic (lead bismuth) is used as coolant. The neutronic performance of an ADS system based on gas cooling was studied in this work by using the simulation tool MCNPX. The usage of the Monte-Carlo method in MCNPX allows the simulation of the physical processes in a 3D-model of the core. In dependence of the spallation target material and design several parameters like the multiplication factors were investigated, in order to analyze the neutronic performance

Protection of Superconducting Magnets in Case of Accidental Beam Losses during HL-LHC Injection

The LHC injection regions accommodate a system of beam-intercepting devices which protect superconducting magnets and other accelerator components in case of mis-steered injected beam or accidentally kicked stored beam, e.g. due to injection kicker or timing malfunctions. The brightness and intensity increase required by the High Luminosity (HL) upgrade of the LHC necessitates a redesign of some devices to improve their robustness and to reduce the leakage of secondary particle showers to downstream magnets. In this paper, we review possible failure scenarios and we quantify the energy deposition in superconducting coils by means of FLUKA shower calculations. Conceptual design studies for the new protection system are presented, with the main focus on the primary injection protection absorber (TDI) and the adjacent mask (TCDD)

Power Deposition in LHC Magnets With and Without Dispersion Suppressor Collimators Downstream of the Betatron Cleaning Insertion

The power deposited in dispersion suppressor (DS) magnets downstream of the LHC betatron cleaning insertion is governed by off-momentum protons which predominantly originate from single-diffractive interactions in primary collimators. With higher beam energy and intensities anticipated in future operation, these clustered proton losses could possibly induce magnet quenches during periods of short beam lifetime. In this paper, we present FLUKA simulations for nominal 7 TeV operation, comparing the existing layout with alternative layouts where selected DS dipoles are substituted by pairs of shorter higher-field magnets and a collimator. Power densities predicted for different collimator settings are compared against present estimates of quench limits. Further, the expected reduction factor due to DS collimators is evaluated

LHC Injection Protection Devices, Thermo-mechanical Studies through the Design Phase

The TDI is a beam intercepting device installed on the two injection lines of the LHC. Its function is to protect the superconducting machine elements during injection in the case of a malfunction of the injection kickers. The TDIS, which will replace the TDI, is foreseen to be installed for high luminosity operation. Due to the higher bunch intensities and smaller beam emittances expected, and following the operational experiences of the TDI, a complete revision of the design of the jaws must be performed, with a main focus on the material selection. Furthermore, the new TDIS will also improve the TDI reliability by means of a robust design of the jaw positioning mechanism, the efficiency of the cooling circuit and by reducing its impedance. A simplified installation procedure and maintenance will also be an important requirement for the new design. This paper introduces the main characteristics of the TDI as LHC injection protection device, showing the needs and requirements for its upgrade. It also discusses the thermo-mechanical simulations that are supporting and guiding the design phase and the material selection, and describes the modifications to be implemented, so far, for this new device