Redefining Debt-to-Health, a triple-win health financing instrument in global health.

BACKGROUND: As a recognized win-win-win approach to international debt relief, Debt-to-Health(D2H)has successfully translated debt repayments into investments in health-related projects. Although D2H has experienced modifications and periodic suspension, it has been playing an increasingly important role in resource mobilization in public health, particularly for low-and middle-income countries deep in debt. MAIN TEXT: D2H, as a practical health financing instrument, is not fully evidenced and gauged by academic literature though. We employed a five-step scoping review methodology. After posing questions, we conducted comprehensive literature searches across three databases and one official website to identify relevant studies.We also supplemented our research with expert interviews. Through this review and interviews, we were able to define the concept and structure of D2H, identify stakeholders, and assess its current shortcomings. Finally, we proposed relevant countermeasures and suggestions. CONCLUSION: This paper examines the D2H project's implementation structure and influencing variables, as well as the current research plan's limitations, with a focus on the role health funding institutions have played during the project's whole life. Simultaneously, it examines the interdependencies between debtor nations, creditor nations, and health financing establishments, establishing the groundwork for augmenting and revamping D2H within the ever-changing worldwide context of health development assistance.

Rethinking international financing for health to better respond to future pandemics.

International financing for health has been high on the political and global health agenda since COVID-19. The recent launch of the Pandemic Fund represents the first consolidated effort of the international community to mobilise additional voluntary financial resources for the purpose of strengthening global efforts in pandemic prevention, preparedness and response (PPR). Against such a dynamic landscape, building on recent critiques and new policy proposals, we propose a new generation of more equitable, effective and coordinated financing arrangements for pandemic PPR and for global health and development more broadly: lessons that could be applied in the ongoing endeavour of the Pandemic Fund. We also explore the principles of Global Public Investment and consider their potential to achieve greater inclusiveness in governance, diversity in financing, and transparency and performance in operations. The Pandemic Fund could become the first example of a global health initiative based on innovative concepts. It needs to be broad based, more flexible, leverage a great variety of funding sources and join forces with multiple stakeholders to maximise the impact.

Association of healthy lifestyle with cognitive function among Chinese older adults.

BACKGROUND/OBJECTIVES: Dietary patterns and daily life habits have been reported to be associated with cognitive function in European populations. We aimed to examine the associations of dietary patterns and daily life habits with cognitive function among Chinese old people. SUBJECTS/METHODS: We used 2011-2014 longitudinal data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) comprising 5716 participants with an average age of 82 years. Cognitive function was measured in 2014 based on the results of Mini-Mental Status Examination. Data on participants' dietary patterns and daily life habits were collected during baseline survey. Logistic regression models and general linear models were adopted to estimate the associations of dietary pattern and daily life habit with cognitive function. RESULTS: Compared with participants in the lowest quartile of lifestyle score, those in the highest quartile had a lower risk of cognitive impairment after controlling for all covariates (OR = 0.52, 95% confidence interval (CI), 0.41-0.65, P < 0.001). Higher lifestyle score was associated with better cognitive function (ß = 0.74, 95% CI, 0.55-0.93, P < 0.001). Participants with top quartile of dietary pattern had a lower risk of cognitive impairment (OR = 0.65, 95% CI, 0.51-0.81, P < 0.001). Similar trends were observed in daily life habit, showing that more exercises, moderate alcohol consumption, and non-smoking were associated with improved cognition status (OR = 0.64, 95% CI, 0.53-0.77, P < 0.001). CONCLUSIONS: Our findings suggest that maintaining a healthy dietary pattern and carrying out outdoor exercises is associated with a lower risk of cognitive impairment among Chinese old people.

Coronavirus disease 2019 (COVID-19) pandemic: how countries should build more resilient health systems for preparedness and response.

OBJECTIVE: A resilient health system plays a crucial role in pandemic preparedness and response. Although the World Health Organization (WHO) has required all states parties to strengthen core capacities to respond to public health emergencies under the International Health Regulations (2005), the actions of most countries to combating coronavirus disease 2019 (COVID-19) has showed that they are not well-prepared. This cross-sectional study aimed to examine the health system resilience of selected countries and analyze their strategies and measures in response to the COVID-19 pandemic. METHODS: This study selected five countries including the Iran, Japan, Republic of Korea (South Korea), the U.K., and the U.S., based on the severity of the national epidemic, the geographical location, and the development level. Cumulative number of death cases derived from WHO COVID-19 dashboard was used to measure the severity of the impact of the pandemic in each country; WHO State Parties Self-Assessment Annual Reporting (SPAR) Scores and Global Health Security (GHS) Index were applied to measure the national health system resilience; and research articles and press materials were summarized to identify the strategies and measures adopted by countries during response to COVID-19. This study applied the resilient health systems framework to analyze health system resilience in the selected countries from five dimensions, including awareness, diversity, self-regulation, integration and adaptation. RESULTS: The SPAR Scores and GHS Index of the four developed countries, Japan, South Korea, the U.K. and the U.S. were above the global and regional averages; the SPAR Scores of Iran were above the global average while the GHI Index lain below the global average. In terms of response strategies, Japan, the U.K. and the U.S. invested more health resources in the treatment of severe patients, while South Korea and Iran had adopted a strategy of extensive testing and identification of suspected patients. In terms of specific measures, all the five countries adopted measures such as restrictions on entry and international travel, closure of schools and industries, lockdown and quarantine. Nevertheless, the effectiveness of implementing these measures varied across countries, based on the response strategies. CONCLUSION: Although SPAR Scores and GHS Index have evaluated the national core capacities for preparedness and response, the actions to cope with the COVID-19 pandemic has revealed the fact that most countries still do not build resilient health systems in response to public health emergencies. Health system strengthening and health security efforts should be pursued in tandem, as part of the same mutually reinforcing approach to developing resilient health systems.

High-purity foam-like micron-sized gold cage material with tunable plasmon properties.

Herein, by growing mono dispersed gold nanoparticles (MNPAu) on the surface of polystyrene (PS)/nanogold (Au) core-shell composites (PS@Au), we successfully synthesized a micron-sized gold cage (2.6-10.7 µm), referred to as PS@Au@MNPAu for the first time. The new micron-gold cage materials exhibit broadband absorption range from near-ultraviolet to near-infrared, which is unlike the conventional nanogold core-shell structure. The uniform growth of MNPAu on the surface forms a new photonic crystal spectrum. The strong coupling of the spectra causes anomalous absorption in the ultraviolet-near infrared band (400-900 nm). Furthermore, by removing the PS core, a nanogold cavity structure referred to as Au@MNPAu was prepared. This structure demonstrated a high purity (> 97 wt%), low density (9-223 mg/cm3), and high specific surface area (854 m2/g). As the purification process progressed, the MNPAu coupling on the surface of the micro-gold cage strengthened, resulting in the formation of peaks around 370 nm, plasma resonant peaks around 495 nm, and structural bands of photonic crystal peaks around 850 nm. The micron-sized gold cage provides hybridized and tunable plasmonic systems. The theoretical simulations indicate that this plasmon anomalous absorption phenomena can be understood as the novel form of the topological structural transitions near the percolation threshold, which is consistent experimental measurements.

Theoretical development and experimental validation on the measurement of temperature by extended X-ray absorption fine structure.

A systematic investigation on the theoretical framework of the ultra-fast measurement of temperature by extended X-ray absorption fine structure (EXAFS) applied in laser-driven-compression experiments has been carried out and a new temperature measurement scheme based on the EXAFS cumulant expansion analysis and anharmonic correlated Debye model has been advanced. By considering the anharmonic effect of thermal vibration and avoiding the employment of the empirical model as well as parameters which have large inherent uncertainties in the temperature determination, this new scheme is theoretically more accurate than traditional ones. Then the performance of the new measurement scheme and traditional methods were validated on a synchrotron radiation platform by temperature-dependent EXAFS (TDEXAFS) experiments on Au, Fe, V and Ti; the results showed that the new scheme could provide the most accurate measured temperatures with much lower uncertainties. This accurate scheme gives a firmer physical ground to the EXAFS temperature measurement technique and can expect to be applied in laser-driven compression experiments and promote the development of matter state research at extreme conditions.

First Octahedral Spherical Hohlraum Energetics Experiment at the SGIII Laser Facility.

The first octahedral spherical hohlraum energetics experiment is accomplished at the SGIII laser facility. For the first time, the 32 laser beams are injected into the octahedral spherical hohlraum through six laser entrance holes. Two techniques are used to diagnose the radiation field of the octahedral spherical hohlraum in order to obtain comprehensive experimental data. The radiation flux streaming out of laser entrance holes is measured by six flat-response x-ray detectors (FXRDs) and four M-band x-ray detectors, which are placed at different locations of the SGIII target chamber. The radiation temperature is derived from the measured flux of FXRD by using the blackbody assumption. The peak radiation temperature inside hohlraum is determined by the shock wave technique. The experimental results show that the octahedral spherical hohlraum radiation temperature is in the range of 170-182 eV with drive laser energies of 71 kJ to 84 kJ. The radiation temperature inside the hohlraum determined by the shock wave technique is about 175 eV at 71 kJ. For the flat-top laser pulse of 3 ns, the conversion efficiency of gas-filled octahedral spherical hohlraum from laser into soft x rays is about 80% according to the two-dimensional numerical simulation.

Development of Thomson scattering system on Shenguang-III prototype laser facility.

A Thomson scattering diagnostic system, using a 263 nm laser as the probe beam, is designed and implemented on Shenguang-III prototype laser facility. The probe beam is provided by an additional beam line completed recently. The diagnostic system allows simultaneous measurements of both ion feature and red-shifted electron feature from plasmas in a high-temperature (≥2 keV) and high-density (≥10(21) cm(-3)) regime. Delicate design is made to satisfy the requirements for successful detection of the electron feature. High-quality ion feature spectra have already been diagnosed via this system in recent experiments with gas-filled hohlraums.

Quantum molecular dynamics study of warm dense iron.

The equation of state, the self-diffusion coefficient and viscosity of fluid iron in the warm dense regime at densities from 12.5 to 25.0 g/cm(3), and temperatures from 0.5 to 15.0 eV have been calculated via quantum molecular dynamics simulations. The principal Hugoniot is in good agreement with nuclear explosive experiments up to ∼ 50 Mbar but predicts lower pressures compared with high intensity laser results. The self-diffusion coefficient and viscosity have been simulated and have been compared with the one-component plasma model. The Stokes-Einstein relationship, defined by connections between the viscosity and the self-diffusion coefficient, has been determined and has been found to be fairly well described by classical predictions.

The influence of laser clipped by the laser entrance hole on hohlraum radiation measurement on Shenguang-III prototype.

Measuring the x-ray flux exiting the target's laser entrance hole (LEH) is the most common diagnostic that quantifies the x-ray intensity inside the laser-driven hohlraum. However, this signal accounts for only a small portion of the incident laser power and thus is likely to be affected by unwanted x-ray background from non-target area, leading to an overestimation of the hohlraum drive. Unwanted emission might be produced when the laser light is clipped by the LEH (LEH clipping) because of a lack of clearance for laser spot, or with a laser spot comprising of discrete structure, or even with a poor pointing accuracy. Its influence on the hohlraum radiation diagnostic is investigated on Shenguang-III prototype laser facility with the typical 1 ns square pulse. The experiment employed three types of targets to excite the unwanted x-ray background from LEH clipping, unconverted light, and both effects, respectively. This work gives an absolute evaluation of x-ray produced by the LEH clipping, which is measured by flat-response x-ray detectors (FXRD) at multiple view angles. The result indicates that there is little variation in measured emission to various view angles, because the unwanted x-rays are mainly generated at the side face of the LEH lip when laser is obliquely incident. Therefore, the LEH clipping brings more overestimation in hohlraum radiation measurement at larger view angle since the hohlraum LEH as an emitting source viewed by FXRD is decreased as the view angle increases. In our condition, the LEH clipping contributes 2%-3.5% overestimation to the hohlraum flux measurement.

Accurate and efficient characterization of streak camera using etalon and fitting method with constraints.

Streak camera is widely used in continuous time diagnostics in fast physical process. To produce accurate result, it requires delicate calibration and a reliable analysis method. High quality sweep-rate data with uncertainty smaller than 0.5% are obtained over the full record area by a constrained fitting method of peak position measurement, with a short pulse laser and an etalon as the fiducial source. The temporal response is linearized by this full-screen sweep-rate data, which eliminates errors in measurement due to nonlinearity and space-distortion inherent in streak camera.

Note: Continuing improvements on the novel flat-response x-ray detector.

This note describes multi-updates of the novel flat-response x-ray detector in fabrication technology, experimental application, and data uncertainty evaluation. Unlike the previous design, the compound filter is combined into one piece through an improved fabrication process that greatly enhanced its self-supporting capability. A method of pinhole-array imaging is introduced into the experimental application process to stop any debris from the hohlraum and to uniformly reduce the radiation flux. The experimental results show that this method works well. Furthermore, a method of uncertainty evaluation of the radiation flux measurement by the novel flat-response x-ray detector has been developed. The influence of the radiation spectrum to the flux measurement is analyzed. The evaluation shows that the relative uncertainty of the radiation flux is about 10% in higher radiation temperature condition (Tr > 150 eV) and 16% in lower radiation temperature condition (Tr < 100 eV).

Quasi-sinusoidal single-order diffraction transmission grating used in x-ray spectroscopy.

A novel design of quasi-sinusoidal single-order diffraction transmission grating (QSTG) is proposed, which can achieve a line density up to thousands line/millimeter as that of traditional transmission gratings with the current level of nanofabrication technique. We fabricate a 1000 line/mm QSTG using the new design approach, and display the calibration results of such QSTG on the soft x-ray beam of synchrotron radiation.

Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region.

A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis.

Note: X-ray streak camera sweep speed calibration.

X-ray streak cameras are extensively used to study transient x-ray processes in experiments carried out on various laser facilities at the Research Center of Laser Fusion. Precise calibration and clear description of the sweep speed of the x-ray streak camera are vital for obtaining precise temporal information to understand the fast physics phenomena. An x-ray streak camera named wide-slit x-ray streak camera has been calibrated using a small-scale laser facility with pulse duration of 8 ps. Sweep speeds on most part of the output screen (charge coupled device) are obtained. These calibration results can be used to correct the nonlinearity of sweep speed in measurement of temporal processes.

Phase-type quantum-dot-array diffraction grating.

A novel phase-type quantum-dot-array diffraction grating (QDADG) is reported. In contrast to an earlier amplitude-type QDADG [C. Wang et al., Rev. Sci. Instrum. 78, 053503 (2007)], the new phase-type QDADG would remove the zeroth order diffraction at some certain wavelength, as well as suppressing the higher-order diffractions. In this paper, the basic concept, the fabrication, the calibration techniques, and the calibration results are presented. Such a grating can be applied in the research fields of beam splitting, laser probe diagnostics, and so on.

Characterization of the diffraction properties of quantum-dot-array diffraction grating.

A new dispersive element named as quantum-dot-array diffraction grating [L. F. Cao, China patent No. 200410081499 (August 10, 2004)] for visible light has been developed and characterized experimentally. A large number of quantum dots distributed on a substrate as sinusoidal function can be used to diffract x rays without higher-order diffraction. The experimental patterns show that the higher-order diffractions which inevitably exist in the spectrum recorded using traditional diffraction gratings can be eliminated effectively by this newly designed element. It indicates that quantum-dot-array diffraction grating could be an attractive alternative of presently used diffraction grating in soft x-ray spectroscopy application to get rid of the higher-order diffraction distortions.