bluuebunny/crossref_metadata_2025 huggingface dataset:
A Neutronics Feasibility Study of the TRIGA LEU Fuel in the 20MWt NIST Research Reactor
Authors: Britton Kyle Anthony , Wu Zeyun
Published: October 2018

The National Bureau of Standards reactor (NBSR) at the National Institute of Standards and Technology (NIST) is under conversion from high enriched uranium (HEU) to the low enriched uranium (LEU) schema under the Reduced Enrichment for Research and Test Reactors program (RERTR) as a part of the Global Threat Reduction Initiative (GTRI). The conversion of the high performance research reactors (HPRR) such as NBSR is a challenging task due to the high flux need (2.5 × 1014 n/cm2-s for the NBSR), as well as other neutronics performance characteristics requirements without significant changes to the external geometrical configuration. One fuel candidate, the General Atomics (GA) UZrH LEU fuel, has showed particular promise in this regard. The TRIGA LEU fuel was initially developed in the 1980s with particular considerations for fuel conversion for high power regimes such as high density research and test reactors. This study performs a neutronics feasibility study of the UZrH LEU fuel schema for the NBSR, examining the accountability and sustainability of the TRIGA fuel when applying it to the NBSR conversion. To identify the best option to deploy the TRIGA fuel to NBSR in terms of key neutronic performance characteristic, the study is carried out with various considerations in the fuel dimensions, fuel rod layout configurations, and structure material selections. Monte Carlo based computational model is used to assist and facilitate the research procedure. The research findings in this study will determine the viability of the TRIGA fuel type for the NBSR conversion, and provide supporting data for future investigations on this subject.
Status of District Heating Reactor and its Development Prospects in China
Authors: Zhao Jing , Xie Fei , Liu Zhihong
Published: October 2018

Nuclear heating reactor is a new type of power plant that uses nuclear energy as heat source. Low temperature nuclear heating reactor should be the forerunner and main force for developing nuclear heating plant in China. Due to the lower water temperature required by the heating system, this dedicated, non-power generating nuclear reactor works at low temperatures and pressures with inherent safety features. The design, construction and operation of the nuclear heating reactors in various countries in the world were reviewed in this paper, and China’s new demonstration nuclear heating project and NHR-200 low-temperature heating reactor which would be used was discussed in the paper. We put forward the developing route and suggestion for the development of low-temperature heating reactor in China.
The Safety Analysis of Multiple Method Fusion on Reactor Scram Subsystem
Authors: Liu Hua , Liu Zhaohui , Yang Xiaohua , Yan Shiyu , Chen Zhi
Published: October 2018

In the design phase of digital instrument control system, the reactor scram subsystem is a complex system that is constructed by hardware, software, system interaction and communication. So the single analysis method such as FMEA and FTA are all have limitations. FMEA and FTA are all based in the accident model with event chain. FTA is not suitable for the discovery of software and communication failures and other problems with high coupling degree, time series association, constraints of control. Three independent basic analysis methods, FMEA, FTA and STPA, are combined to form the statistical table of failure and failure coverage. For FMEA and FTA, the design safety problem detection rate is only 74.1% and 64% respectively for reactor scram subsystem. The detection rate of STPA for reactor SCRAM subsystem is up to 95.1%. Meanwhile, multiple method fusion can cover all the safety issues triggered by hardware, software, system interaction, and communication failure and defect. The analysis of this paper shows that multiple method fusion is better than single method. STPA method is superior to other single security analysis methods. STPA method can effectively make up for the inadequacy of FMEA and FTA method.
Sensitivity Analysis of Turbulence Models for the Core Inlet Flow Distribution of PWR
Authors: Hao Lu-lu , Chen Hong , Qiu Su chen
Published: October 2018

Computational Fluid Dynamics (CFD) methods have been developed into effective fluid simulation means to be used on the hydraulic design in the field of nuclear reactor. However, it is difficult to generate suitable mesh and select turbulence model for simulation because of the complex geometry structure and flow behavior in the pressure vessel. Based on CFX software, a hydraulic computation model of typical pressurized water reactor is established and the flow distribution at core inlet is analyzed. The simplified geometry model consists cold legs, downcomer, lower plenum, secondary support component, core support plate, and lower core plate. The computation model is divided into three parts for mesh generation, including the part of inlet and downcomer, the part of lower plenum and core inlet section, and the part of core. In order to reach the independence of grid several methods of mesh generation which contains different mesh density at local key parties are investigated to screen out the suitable mesh scheme. The k-ε, k-ω, and SST k-ω turbulence model are respectively used for simulation and the sensitivity of turbulence model at different locations of flow field is analyzed. The results show that the mass flow rate of the near wall flow field, computed by using k-ω turbulence model, is consistent with SST k-ω model, while the mass flow rate of central flow field computed by using k-ε turbulence agrees with SST k-ω model. The result computed by using k-ε turbulence model shows relatively uniform flow distribution at core inlet, which is more consistent with the measured data with the average difference of 3.1%. By using the k-ε model, the probability distribution of the difference between the calculated results and the experimental values follows the law of Normal distribution. The final coolant flow distribution at each orifice is evaluated, and the maximum normalized flow flux is found at center orifice while the flow rate at the edge of core is relatively lower.
Data-Driven Fault Diagnosis for Nuclear Power Plant: The Implicit Model Approach
Authors: Chen Zhaoxu , Li Xianling , Ke Zhiwu , Tao Mo , Feng Yi
Published: October 2018

This paper proposes a data-driven fault detection approach for nuclear power plant. The approach starts from input and output (I/O) data obtained from operating data of industrial process. Due to the model is not explicitly appeared, the proposed approach is named as implicit model approach (IMA). Residual generator is obtained directly from I/O data rather than from the mechanism, based which the algorithm of IMA-based fault detection is proposed. The main advantage of IMA-based fault detection is that it can circumvent complicated model identification. The approach generates parameterized matrices of residual signal inspired by subspace relevant technology without any prior knowledge about mechanisms of the plant. Fault information has been injected to a simulating platform of a compact reactor in the simulation part, by which we verify the effectiveness of IMA-based fault detection.
Study on Gas Entrainment From Unstable Drifting Vortexes on Liquid Surface
Authors: Hirakawa Moe , Kikuchi Yuichiro , Sakai Takaaki , Tanaka Masaaki , Ohshima Hiroyuki
Published: October 2018

Gas entrainment (GE) from cover gas, which is an inert gas to cover Sodium coolant in a reactor vessel, is one of key issue for Sodium-cooled fast reactors (SFRs) design to prevent unexpected effects to core reactivity. In this study, evaluation method has been investigated for surface dimple depth growth of unstable drifting vortex dimples on the liquid surface in the reactor vessel. By using a computational fluid dynamics (CFD) code, analyses have been conducted to estimate the drifting vortexes on water experiments in the circulating water tunnel. The unstable drifting flow vortexes on the water surface were generated as wake vortexes behind a plate obstacle. Downward flow velocity was induced by bottom slit flow pass along the flow channel. In CFD analysis, flat water surface assumption was used with free-slip model for the development of a conventional design method. The gas core lengths from the surface vortexes were evaluated based on existing non-dimensional numbers method by using the stream-viewer code provided from Japan Atomic Energy Agency (JAEA). In this paper, the results of comparison between experiments and analyses were discussed.
Analysis of the Alarm Generation and Display for the Reactor Accidents in HTR-PM
Authors: Guo Chao , Zhou Shuqiao , Li Duo , Huang Xiaojin
Published: October 2018

Nuclear safety is one of the key issues for a nuclear power plant (NPP). The alarm system plays a critical role for the safe and efficient operation of an NPP which affects the correctness and efficiency of the operators in dealing with the accidents. It is even more important for the alarm system of a multi-modular NPP which has more than one reactor modules in a single unit because all the modules are usually monitored in the same main control room. The alarm generation and display mechanism of a typical multi-modular NPP, the High Temperature Gas-Cooled Reactor - Pebble bed Module (HTR-PM), is analyzed in this paper which has two reactor modules coupled to one steam turbine. Three operators are responsible for the operation of two nuclear islands and a conventional island, respectively. The alarm generation and display processes will be discussed in this paper. Firstly, the architecture of the RPS and the alarm system related to the red and yellow alarms is introduced. Then the generation and display mechanism of the red and yellow alarms is proposed. A protection variable of a design basis accident is given as an example for the alarm signal handling. The characteristics of the alarm system are then discussed. More optimization directions on the alarm design for multi-modular NPPs are proposed in the end.
On the Liquid Film Flow Characteristics During the Rewetting in the Single Rod Air-Water System
Authors: Wada Yuki , Le Dan , Satou Akira , Sibamoto Yasuteru , Yonomoto Taisuke
Published: October 2018

Dry-out and rewetting phenomenon may occur on a fuel rod surface during anticipated operational occurrences (AOOs) for a boiling water reactor (BWR). The conventional rewetting model included in the current system code tends to underestimate the rewetting propagation velocity due to the absence of an appropriate precursory cooling model. The present research aims at the development of a mechanistic model for the precursory cooling in the annular mist flow regime typical of AOO and anticipated transition without scrum (ATWS). Rewetting experiments were carried out using a single heater rod in the circular glass pipe with air-water flow at atmospheric pressure to visualize the rewetting behavior and obtain mechanistic understanding on the phenomena. This paper summarizes the experimental results and discusses the liquid film flow characteristics including roll wave formation and spattering at the rewetting front.
Experimental Comparison on the Multi-Hole Steam Spraying Condensation Heat Transfer Characteristics
Authors: Zhang Yuhao , Lu Daogang , Ouyang Bin , Yuan Yonglong
Published: October 2018

In the third generation pressurized water reactor AP1000 plant, the Automatic Depressurization System (ADS) is one of the most important passive safety system. As the steam continues to discharge into the IRWST, the high-temperature and high-pressure steam condenses in the IRWST intensely and rapidly. In the present work, multi-hole spargers DCC experimental bench has been built to study the condensation and mixing phenomena in the accidental depressurization events in AP1000. The key parameters including the temperature, velocity, and flow patterns are monitored by the thermocouples, PIV technique, and high speed camera, etc. Based on the experimental results, the heat transfer characteristics of the steam-jet Direct Contact Condensation (DCC) in the ADS depressurization process were analyzed. The experimental comparison shows that the spraying steam behaviors are closely related to the steam mass flux, which determined the ejection patterns. The spraying steam is condensed rapidly in the core region with the flow regime locating in chugging, transitional chugging, and stable ejection stages. The 88-hole experimental results fit well with Fukuda’s condensation oscillation correlations, whereas the 2-hole experimental results are slightly lower than the values predicted by traditional single hole correlation.
Application of Similarity Law in Electrical Device Design in Helium for High Temperature Gas-Cooled Reactor
Authors: Chen Xiaohuan , Geng Yinan , Wang Jie
Published: October 2018

The High Temperature Gas-cooled Reactor (HTGR) designed by Tsinghua university is under development in China. The electrical equipment in Pressure Vessel, such as magnetic bearings and helium circulator are operating in the high pressure helium environment. Design research of insulation property of the electrical device in helium under high pressure is necessary. Nevertheless, it is challenging to investigate by experimental technique. We propose a similarity law, converting the high pressure to a lower pressure to simplify the experimental conditions. Similarity theory of gas discharge is that two geometrically similar gaps with scaling coefficients of k, based on the same product number of pressure p and the gas length d, have the similar discharge characteristics. We research the validity of discharge similarity theory by simulation. A fluid model of direct-current discharge in helium atmosphere was established, referencing experimental results. And the discharge models of gaps were solved by finite-element method respectively. Four geometrically similar gaps were designed, the prototype gap is 2cm long and operating at a pressure of 600Pa while the pressure of three similar gaps are 300Pa, 200Pa, and 120Pa, and corresponding to the length of gaps are 4cm, 6cm and 10cm, with scaled-down factor k of 2, 3, and 5 respectively. The simulation results show that as long as the scaled-down factor of pressure k is less than 5 and the reduced length relation meets the condition p1d1 = p2d2, the discharge characteristics of two geometrically similar gaps are similar. As a result, it is realizable to predict the insulation property of electrical device in helium with similarity law.
A Non-Contact Ultrasonic Sensor for General Corrosion Inspection of Thin Plates
Authors: Tamura Akinori , Miki Masahiro , Kono Naoyuki , Okazawa Hiroshi , Okido Shinobu , Zhong Chenghuan , Fabre Erik , Croxford Anthony J. , Wilcox Paul D.
Published: October 2018

In power plants, there are structures made up of thin plates, such as air-conditioning ducts or thin-walled pipes, where corrosion can occur. In this study, we provide a solution to reduce inspection time of the thin plate corrosion measurement and enable monitoring, using a non-contact ultrasonic sensor. The sensor can measure the reduction in thickness of thin plates due to general corrosion without the need to remove or reinstall insulating material that is on the outside of the plate. The proposed sensor is based on the non-contact ultrasonic measurement technique which was originally proposed by Greve et al, further developed and patented by Zhong et al. at the University of Bristol, and commercialized by Inductosense Ltd. In order to ultrasonically measure the thin plate thickness, we use a method based on the group velocity of the guided waves. The proposed method was tested theoretically with numerical simulations and experimentally against our target conditions. The results of the numerical simulations and experiments confirm that the proposed method can be applied to thickness measurements of thin-plates in our target condition. Based on the feasibility test results, we developed a prototype sensor and measurement software. From the results of the performance evaluation tests, we have confirmed that the prototype sensor has sufficient capability to measure the thickness of the thin plates without the removal of the insulator. Even if the offset between the plate and the inspection probe is 100 mm, the prototype sensor still works well.
Dynamic Modeling of the NSSS Based on NHR200-II Nuclear Heating Reactor
Authors: Dong Zhe , Pan Yifei , Liu Miao , Huang Xiaojin
Published: October 2018

The nuclear heating reactor (NHR) is a typical integral pressurized water reactor (iPWR) developed by the institute of nuclear and new energy technology (INET) of Tsinghua University, which has the safety advanced features such as the primary circuit integral arrangement, full-range natural circulation, self-pressurization. Power-level control is crucial for the operational stability and efficiency of the NHR, and the dynamic modeling is a basis for control system design and verification. From the conservation laws of mass, energy and momentum, a lumped-parameter dynamical model is proposed for the nuclear steam supply system (NSSS) based on the 200MWth nuclear heating reactor II (NHR200-II). The steady-state model validation is given by the comparing the parameter values of this model and that for plant design. Then, both the open-loop responses under the disturbances of reactivity and coolant flowrates as well as the closed-loop responses under the case of power ramp are given, where the rationality of the responses are analyzed from the viewpoint of plant physics and thermal-hydraulics. This model can be utilized for not only the control system design but also the development of a real-time simulator for the hardware-in-loop control system verification.
Standby Equipment Reliability Data Analysis on Risk Monitor of Nuclear Power Plant
Authors: Ma Yingfei , Zhang Zhijian , Wang He , Chen Sijuan , Xu Anqi , Zheng Gangyang
Published: October 2018

Reliability data works as the basis of risk monitor of nuclear power plant. The failure modes of the equipment in a nuclear power plant can be divided into operation failure, demand failure and standby failure. A standby equipment is affected by the demand stress and the standby stress simultaneously, so the method of reliability data analysis must consider the two types of failure. The reliability data in online risk monitor should reflect the change of equipment reliability with time, including standby equipment. A method to deal with the reliability data of the standby equipment is presented in this paper. This model takes into account the failure of the equipment during the spare time and the failure of the starting time. Considering the characteristics of the reliability data in the nuclear power plant, the method of parameter estimation is studied. Finally, this method is applied to online risk monitor in nuclear power plant and the suggestion of reliability data application is put forward.
Seismic Analysis and Design of HPR1000 Degassing Tower Liquid Cooler
Authors: Dang Junjie , Li Wenmo , Wang Chunming , Tang Xingling
Published: October 2018

The degassing tower liquid cooler is an important equipment for boron recovery system of HPR1000 nuclear power plant. It is crucial to ensure the security function of degassing tower liquid cooler under earthquake. This report carried out a seismic analysis for the degassing tower liquid cooler. The finite element (FE) model for the Degassing Tower Liquid Cooler was established by using the ANSYS code. The response spectrum method was adopted for the equipment seismic analysis and evaluation. Through the seismic analysis, the design weakness of the degassing tower liquid cooler was identified. And the weakness was modified to meet the requirement of practical engineering according to the FE results and the relevant specification.
The ENEN+ Project: Attracting, Retaining and Developing New Nuclear Talents Beyond Academic Curricula
Authors: Cizelj Leon , Pesznyak Csilla , Bazargan-Sabet Behrooz , Abdelouas Abdesselam , Tuomisto Filip , Coeck Michèle , Dieguez Porras Pedro
Published: October 2018

The ENEN+ project proposes cost-effective actions to attract, develop and retain new talents in nuclear professions. This is a contribution of the ENEN Association, supported by the European Commission, to the common strategic goal of all nuclear stakeholders: to preserve, maintain and further develop the valuable nuclear knowledge for todays and future generations. The ENEN+ project focuses on learners and careers in nuclear reactor engineering and safety, waste management and geological disposal, radiation protection and medical applications. This paper outlines the most important expected contributions of the project and the approaches designed to deliver them.
Development of a Crack Opening Displacement Assessment Procedure Considering Change of Compliance at a Crack Part in Thin Wall Pipes Made of Modified 9Cr-1Mo Steel
Authors: Wakai Takashi , Machida Hideo , Arakawa Manabu , Yanagihara Seiji , Suzuki Ryosuke , Matsubara Masaaki
Published: October 2018

This study was carried out to establish crack opening displacement (COD) evaluation methods used in Leak-Before-Break (LBB) assessment of thin-walled large-diameter pipes of the Sodium cooled Fast Reactors (SFRs). For the pipes of SFR, the continuous leak monitoring will be adopted as an alternative to a volumetric test of the weld joints under conditions that satisfy LBB. The sodium pipes are made of ASME Gr.91 (modified 9Cr-1Mo steel). Thickness of the pipes is small, because the internal pressure is very small. Modified 9Cr-1Mo steel has a relatively large yield stress and small work hardening coefficient comparing to the austenitic stainless steels which are currently used in the conventional plants. In order to assess the LBB behavior of the sodium pipes made of modified 9Cr-1Mo steel, the coolant leak rate from a through wall crack must be estimated properly. Since the leak rate is strongly related to the crack opening displacement (COD), an appropriate COD assessment method must be established to perform LBB assessment. However, COD assessment method applicable for SFR pipes — having thin wall thickness and made of small work hardening material — has not been proposed yet. Thus, a COD assessment method applicable to thin walled large diameter pipe made of modified 9Cr-1Mo steel was proposed in this study. In this method, COD was calculated by classifying the components of COD; elastic, local plastic and fully plastic. In addition, the verification of this method was performed by comparing with the results of a series of four-point bending tests using modified 9Cr-1Mo steel pipe having a circumferential through wall notch. As a result, in some cases, COD were overestimated especially for large cracks. Although the elastic component of COD, δEE, is still over-estimated for large cracks, leak evaluation from small cracks is much more important in LBB assessment. Therefore, this study recommends that only the elastic component of COD, δEE, should be adopted in LBB assessment of SFR pipes.
Collegiate Recreational Sports Participation as an Adjustment Aid for Former High School Athletes Experiencing Athlete Role Exit
Authors: Helms Katie , Moiseichik Merry
Published: October 2018

Successful transition to college is an important consideration in student retention and success. Students who highly identify as high school athletes may experience adjustment difficulty when entering college without this role. The current study investigates participation in collegiate recreation programs as part of a positive adjustment process after the transition out of high school athletics. Results indicated that those with high involvement in collegiate recreation programs had greater perceptions of loss related to the cessation of their athlete role, but also experienced greater perceptions of life satisfaction. Feelings of loss following sport role exit were found to interact with recreational sports involvement on the outcome variable of life satisfaction. Specifically, among those with high loss levels, high recreational sports involvement was associated with greater satisfaction. Results have implications regarding the support of collegiate recreation as a contributor to the successful transition to college, particularly for students experiencing difficulty related to an exit from the high school athlete role.
Quantitative changes in the ageing choriocapillaris as measured by swept source optical coherence tomography angiography
Authors: Sacconi Riccardo , Borrelli Enrico , Corbelli Eleonora , Capone Luigi , Rabiolo Alessandro , Carnevali Adriano , Casaluci Marco , Gelormini Francesco , Querques Lea , Bandello Francesco , Querques Giuseppe
Published: October 2018

Aim

To analyse quantitative optical coherence tomography angiography (OCTA) parameters of choriocapillaris (CC) at the foveal, perifoveal and parafoveal regions in healthy subjects of different age.

Methods

In this observational cross-sectional study, consecutive healthy subjects underwent swept source OCTA (PLEX Elite 9000, Carl Zeiss Meditec, USA). 3×3 mm and 6×6 mm scans centred on the fovea were acquired analysed and postprocessed with thresholding and binarisation processes. The main outcome measures included CC quantitative OCTA features (perfusion density (PD), vessel length density (VLD) and vessel diameter index (VDI)) at the foveal, perifoveal and parafoveal regions, and their relationship with age.

Results

Seventy-two eyes (72 patients, mean age 47.4±19.2 years, mean axial length 24.0±0.7 mm) were included. The mean PD was statistically lower in the foveal region compared with the parafoveal region in 3×3 mm scans (p=0.009). In subjects aged 70–80, PD of the foveal region was significantly reduced compared with the perifoveal region in 6×6 mm scans (p=0.008). A strong negative correlation was found between PD and ageing in the foveal, parafoveal and perifoveal regions (p<0.001 in all analyses). Furthermore, PD in the nasal-perifoveal region was significantly lower than the temporal-perifoveal region (p=0.005). No significant correlation was found between VLD and age in all regions, whereas VDI was strictly correlated with age (p<0.001).

Conclusions

We reported in vivo a strong negative correlation between PD and ageing in the CC of healthy subjects. This reduction seems related to a reduced diameter, and not to a reduced number, of capillaries. The age-related changes were higher in the central area compared with the perifoveal area.
Efficacy, effectiveness, and safety of herpes zoster vaccines in adults aged 50 and older: systematic review and network meta-analysis
Authors: Tricco Andrea C , Zarin Wasifa , Cardoso Roberta , Veroniki Areti-Angeliki , Khan Paul A , Nincic Vera , Ghassemi Marco , Warren Rachel , Sharpe Jane P , Page Andrea V , Straus Sharon E
Published: October 2018

Objective

To compare the efficacy, effectiveness, and safety of the herpes zoster live attenuated vaccine with the herpes zoster adjuvant recombinant subunit vaccine or placebo for adults aged 50 and older.

Design

Systematic review with bayesian meta-analysis and network meta-analysis.

Data sources

Medline, Embase, and Cochrane Library (inception to January 2017), grey literature, and reference lists of included studies.

Eligibility criteria for study selection

Experimental, quasi-experimental, and observational studies that compared the live attenuated vaccine with the adjuvant recombinant subunit vaccine, placebo, or no vaccine in adults aged 50 and older. Relevant outcomes were incidence of herpes zoster (primary outcome), herpes zoster ophthalmicus, post-herpetic neuralgia, quality of life, adverse events, and death.

Results

27 studies (22 randomised controlled trials) including 2 044 504 patients, along with 18 companion reports, were included after screening 2037 titles and abstracts, followed by 175 full text articles. Network meta-analysis of five randomised controlled trials found no statistically significant differences between the live attenuated vaccine and placebo for incidence of laboratory confirmed herpes zoster. The adjuvant recombinant subunit vaccine, however, was statistically superior to both the live attenuated vaccine (vaccine efficacy 85%, 95% credible interval 31% to 98%) and placebo (94%, 79% to 98%). Network meta-analysis of 11 randomised controlled trials showed the adjuvant recombinant subunit vaccine to be associated with statistically more adverse events at injection sites than the live attenuated vaccine (relative risk 1.79, 95% credible interval 1.05 to 2.34; risk difference 30%, 95% credible interval 2% to 51%) and placebo (5.63, 3.57 to 7.29 and 53%, 30% to 73%, respectively). Network meta-analysis of nine randomised controlled trials showed the adjuvant recombinant subunit vaccine to be associated with statistically more systemic adverse events than placebo (2.28, 1.45 to 3.65 and 20%, 6% to 40%, respectively).

Conclusions

Using the adjuvant recombinant subunit vaccine might prevent more cases of herpes zoster than using the live attenuated vaccine, but the adjuvant recombinant subunit vaccine also carries a greater risk of adverse events at injection sites.

Protocol registration

Prospero CRD42017056389.
Strategic purchasing for universal health coverage: examining the purchaser–provider relationship within a social health insurance scheme in Nigeria
Authors: Etiaba Enyi , Onwujekwe Obinna , Honda Ayako , Ibe Ogochukwu , Uzochukwu Benjamin , Hanson Kara
Published: October 2018

Background

In an attempt to achieve universal health coverage, Nigeria introduced a number of health insurance schemes. One of them, the Formal Sector Social Health Insurance Programme (FSSHIP), was launched in 2005 to provide health cover to federal government and formal private sector employees. It operates with two levels of purchasers, the National Health Insurance Scheme (NHIS) and health maintenance organisations (HMOs). This study critically assesses purchasing arrangements between NHIS, HMOs and healthcare providers and determines how the arrangements function from a strategic purchasing perspective within the FSSHIP.

Methods

A qualitative study undertaken in Enugu state, Nigeria, data were gathered through reviews of documents, 17 in-depth interviews (IDIs) with NHIS, HMOs and healthcare providers and two focus group discussions (FGDs) with FSSHIP enrolees. A strategic purchasing lens was used to guide data analysis.

Results

The purchasing function was not being used strategically to influence provider behaviour and improve efficiency and quality in healthcare service delivery. For the purchaser–provider relationship, these actions are: accreditation of healthcare providers; monitoring of HMOs and healthcare providers and use of appropriate provider payment mechanisms for healthcare services at every level. The government lacks resources and political will to perform their stewardship role while provider dissatisfaction with payments and reimbursements adversely affected service provision to enrolled members. Underlying this inability to purchase, health services strategically is the two-tiered purchasing mechanism wherein NHIS is not adequately exercising its stewardship role to monitor and guide HMOs to fulfil their roles and responsibilities as purchasing administrators.

Conclusions

Purchasing under the FSSHIP is more passive than strategic. Governance framework requires strengthening and clarity for optimal implementation so as to ensure that both levels of purchasers undertake strategic purchasing actions. Additional strengthening of NHIS is needed for it to have capacity to play its stewardship role in the FSSHIP.
Using a mentorship model to localise the Practical Approach to Care Kit (PACK): from South Africa to Brazil
Authors: Wattrus Camilla , Zepeda Jorge , Cornick Ruth Vania , Zonta Ronaldo , Pacheco de Andrade Matheus , Fairall Lara , Georgeu-Pepper Daniella , Anderson Lauren , Eastman Tracy , Bateman Eric D , CRUZ Alvaro A , Bachmann Max O , Natal Sonia , Doherty Tanya , Stelmach Rafael
Published: October 2018

Brazil’s Sistema Único de Saúde, or Unified Health System policy, has delivered major improvements in health coverage and outcomes, but challenges remain, including the rise of non-communicable diseases (NCDs) and variations in quality of care across the country. Some of these challenges may be met through the adaptation and implementation of a South African primary care strategy, the Practical Approach to Care Kit (PACK). Developed by the University of Cape Town’s Knowledge Translation Unit (KTU), PACK is intended for in-country adaptation by employing a mentorship model. Using this approach, the PACK Adult guide and training materials were localised for use in Florianópolis, Santa Catarina, Brazil, as part of an initiative to reform primary care, expand care for NCDs and make services more accessible and equitable. The value of the collaboration between the KTU and Florianópolis municipality is the transfer of skills and avoidance of duplication of effort involved in de-novo guide development, while ensuring that materials are locally acceptable and applicable. The collaboration has informed the development of the KTU’s PACK mentorship package and led to a relationship between the groups of developers, ensuring ongoing learning and research, with the potential of assisting the further scale-up of PACK in Brazil.
Equity and determinants of routine child immunisation programme among tribal and non-tribal populations in rural Tangail subdistrict, Bangladesh: a cohort study
Authors: Rahman Aminur , Reza Ashek Ahmed Shahid , Bhuiyan Badrul Alam , Alam Nurul , Dasgupta Shushil K , Mostari Shabnam , Anwar Iqbal
Published: October 2018

Objectives

The study estimated valid vaccination coverage of under 5 children in a rural area under Tangail subdistrict and examined their sociodemographic correlates including ethnicity.

Setting

The study sites are three primary areas where tribal and non-tribal population resides together in a rural subdistrict of Bangladesh.

Participants

Routine vaccination information of a cohort of 2802 children, born between 1 January 2011 and 31 December 2012, were retrieved from the Expanded Program on Immunization (EPI) registers maintained by the health assistants. Collected data were entered in an Oracle-based computer program. Univariate, bivariate and multivariate analyses were performed in SPSS V.20 to explore coverage and differentials for full valid vaccination coverage in the study area.

Results

Valid vaccination coverage was 90.6% among tribal population and 87.3% among non-tribal population(p=0.25). Compared with females, males had higher valid vaccination coverage (89.2% vs 85.9%) and lower invalid (5.4% vs 6.9%) and no-coverage (5.3% vs 7.3%) (p=0.03). Households with mobile phones had higher valid coverage (90.9% vs 86.5%) and lower invalid (4.5% vs 6.7%) and no coverage (4.5% vs 6.9%) compared with those without mobile phones (p=0.01). Coverage of valid vaccination was higher among children of Oronkhola union than in children of the other two unions.

Conclusion

The study documented that valid vaccination coverage was high in this rural area, and there was no significant ethnic variation which was one of the strengths of the national EPI. However, there is significant variation by gender of the child, household ownership of mobile phones and geographical location of households.
Self-rated health among migrants from the former Soviet Union in Germany: a cross-sectional study
Authors: Stolpe Susanne , Ouma Mary , Winkler Volker , Meisinger Christa , Becher Heiko , Deckert Andreas
Published: October 2018

Objectives

To assess the status and change in self-rated health among Aussiedler, ethnic German immigrants from the former Soviet Union, as a predictor for premature death 10 years after first assessment. Moreover, to identify subgroups which are particular at risk of anticipated severe health impairment.

Design

Cross-sectional questionnaire.

Setting

The study was conducted in the catchment area of Augsburg, a city in southern Bavaria, Germany, in 2011/2012 that has a large community of Aussiedler.

Participants

595 Aussiedler (231 male, 364 female, mean age 55 years) who in majority migrated to Germany between 1990 and 1999.

Outcome

Primary outcome: self-rated health (very good/good/not so good/bad) and its association with demographic, social and morbidity related variables.

Methods

Self-rated health was dichotomised as ‘very good’ and ‘good’ versus ‘not so good’ and ‘bad’. Multivariable logistic models were created. Missing values with regard to pain were addressed by a second analysis.

Results

Although low response suggests a healthier sample, the findings are alarming. Altogether47% of the Aussiedler perceived their health as less than good, which is worse compared with the first assessment in 2000 (25% compared with 20% of the general public). Prevalence of high blood pressure was present in 52% of Aussiedler, 34.5% were obese, 40.7% suffered from frequent pain and 13.1% had diabetes mellitus. According to the multivariable models, individuals suffering from pain, limited mobility, diabetes mellitus and high blood pressure are particularly in jeopardy.

Conclusions

10 years after the first assessment of self-rated health among Aussiedler their situation deteriorated. Tailored risk factor counselling of general practitioners is highly recommended.
Percutaneous coronary intervention in patients with acute coronary syndrome in Chinese Military Hospitals, 2011–2014: a retrospective observational study of a national registry
Authors: Zhao Ren , Xu Kai , Li Yi , Qiu Miaohan , Han Yaling
Published: October 2018

Objectives

Interventional treatment of patients with acute coronary syndrome (ACS) is surging dramatically in China in recent years, whereas nationwide assessments of the quality of percutaneous coronary intervention (PCI) procedural performance and outcomes are scarce. We aimed to provide an updated and real-world overview of the performance of PCI in patients with ACS since 2011 in China after the China PEACE study from 2001 to 2011.

Methods

In this cross-sectional study, data were extracted from the National Registry of Cardiovascular Intervention in Military Hospitals database to create a national sample of 144 659 patients with ACS undergoing PCI at 117 military hospitals in all regions of China from calendar years 2011–2014. Patient characteristics, procedural performance, PCI outcomes and adverse events and temporal changes were analysed.

Results

During 2011–2014, patients with ACS undergoing PCI increased dramatically. Small numbers of high-volume hospitals performed the majority of PCI procedures. However, only half of these patients were adequately covered and proportions for the use of assisted devices and novel medications were relatively small. Radial artery access was still increasing with time. Primary PCIs were performed on 45.4% ST-segment elevation myocardial infarction patients with PCI procedures. 3.8% lesion vessels involve left main artery. Implanted stents, the overall complications and in-hospital mortality were decreasing remarkably.

Conclusions

In Chinese military hospitals, interventional resources were limited with great regional disparities, there are still gaps to be filled to better serve patients with ACS. Our findings can serve as an indispensable supplement to a more comprehensive understanding of the practice of contemporary cardiac intervention in China.
Prostate cancer diagnostic pathway: Is a one-stop cognitive MRI targeted biopsy service a realistic goal in everyday practice? A pilot cohort in a tertiary referral centre in the UK
Authors: Bass Edward James , Freeman Alex , Jameson Charles , Punwani Shonit , Moore Caroline M , Arya Manit , Emberton Mark , Ahmed Hashim Uddin
Published: October 2018

Objectives

To evaluate the feasibility of a novel multiparametric MRI (mpMRI) and cognitive fusion transperineal targeted biopsy (MRTB) led prostate cancer (PCa) diagnostic service with regard to cancer detection and reducing time to diagnosis and treatment.

Design

Consecutive men being investigated for possible PCa under the UK 2-week wait guidelines.

Setting

Tertiary referral centre for PCa in the UK.

Participants

Men referred with a raised prostate-specific antigen (PSA) or abnormal digital rectal examination between February 2015 and March 2016 under the UK 2-week rule guideline.

Interventions

An mpMRI was performed prior to patients attending clinic, on the same day. If required, MRTB was offered. Results were available within 48 hours and discussed at a specialist multidisciplinary team meeting. Patients returned for counselling within 7 days

Primary and secondary outcome measures

Outcome measures in this regard included the time to diagnosis and treatment of patients referred with a suspicion of PCa. Quality control outcome measures included clinically significant and total cancer detection rates.

Results

112 men were referred to the service. 111 (99.1%) underwent mpMRI. Median PSA was 9.4 ng/mL (IQR 5.6–21.0). 87 patients had a target on mpMRI with 25 scoring Likert 3/5 for likelihood of disease, 26 4/5 and 36 5/5.

57 (51%) patients received a local anaesthetic, Magnetic resonance imaging targeted biopsy (MRTB). Cancer was detected in 45 (79%). 43 (96%) had University College London definition 2 disease or greater. The times to diagnosis and treatment were a median of 8 and 20 days, respectively.

Conclusions

This approach greatly reduces the time to diagnosis and treatment. Detection rates of significant cancer are high. Similar services may be valuable to patients with a potential diagnosis of PCa.
What do we really know about PRN use in agitated children with mental health conditions: a clinical review
Authors: Baker Megan , Carlson Gabriellle A
Published: October 2018

What is the evidence that ‘pro re nata’ (PRN) medication is effective for ending agitated outbursts in children and adolescents in psychiatric emergency rooms or inpatient units? Literature search was performed for studies of PRN medication use in children and adolescents that included an outcome measure. One randomised controlled trial, three prospective studies and six retrospective studies that included some outcome measure were identified. Outcome measures were heterogeneous, and frequently did not use standardised metrics assessing agitation level to measure effectiveness. The single small Randomized Controlled Trial (RTC) does not find a difference between placebo and medication, and outcomes of other studies do not control for potential placebo effect of the intervention itself as opposed to the medication. There is insufficient evidence to support the common practice of PRN medications for the management of acute agitation, and no data with which to inform clinical practice, such as which medicines and doses are helpful for specific populations or situations. Psychiatrists have no evidence-based medication interventions for acutely managing agitated outbursts in children and adolescents.
Inverse association of pulse pressure augmentation during exercise with heart failure and death
Authors: Al Rifai Mahmoud , Blaha Michael J , Rahman Faisal , Ehrman Jonathan K , Brawner Clinton A , Keteyian Steven J , Al-Mallah Mouaz H , McEvoy John William
Published: October 2018

Objective

Resting pulse pressure (PP) is a risk factor for heart failure (HF); however, whether PP augmentation during exercise, a parameter easily obtained from routine treadmill stress testing, is associated with incident HF is unknown. Thus, we aimed to study the relationship between a novel parameter, the pulse pressure stress index (P2SI), and adverse outcomes among adults undergoing clinical exercise stress testing in the Henry Ford Exercise Testing Project.

Methods

The P2SI was calculated as PP at peak exercise divided by resting PP and was analysed continuously and categorically using quartiles. Cox models examined the association between P2SI and adjusted HR (aHR) of incident HF, myocardial infarction (MI) or death. Receiver operating curve (ROC) analyses tested the optimal prognostic cut-point for P2SI.

Results

Among 55 524 participants without prior MI or HF, mean (SD) age was 53 (13) years, 51% were men and 29% black. A total of 2516 HF, 1606 MI and 6224 mortality outcomes occurred. Quartile 3 P2SI (2.0–2.4) was chosen as the reference category based on ROC analyses. There was a graded inverse association of low P2SI with excess HF (aHR of 1.3 (95% CI 1.1 to 1.5) for quartile 2 and 1.5 (95% CI 1.2 to 1.8) for quartile 1, p for trend<0.001) and mortality (aHR of 1.1 (95% CI 1.01 to 1.2) for quartile 2 and 1.3 (95% CI 1.2 to 1.5) for quartile 1, p for trend<0.001). There was no association between P2SI and MI after adjustment. P2SI added significant prognostic information to more established stress testing parameters such as peak systolic blood pressure, per cent maximal predicted heart rate achieved and metabolic equivalents of task achieved.

Conclusions

Poor augmentation of PP with exercise, specifically a P2SI below 2, is a novel and readily quantifiable exercise-based risk feature for HF and death.
Perceived effectiveness of objective features of pictorial warning messages
Authors: Sutton Jazmyne A , Yang Sijia , Cappella Joseph N
Published: October 2018

Background

Previous research shows that pictorial warning messages (PWMs) for tobacco cigarettes increase quit attempts and smoking-related knowledge. However, few studies have investigated what specific features within PWMs are most effective. The current study sought to examine the specific features of PWMs associated with effectiveness using four outcome measures as indicators.

Method

A sample of n=319 PWMs was collected and underwent systematic content analysis on 48 different content features. A sample of n=1392 current smokers each rated a subset of the labels on perceived effectiveness, negative emotional engagement, intentions to enact avoidance behaviours and intentions to forego a cigarette. Multilevel random-effects models were fitted with all coded content features and each of the outcome measures.

Results

Analysis across all four outcome measures shows that PWMs depicting diseased and damaged body parts and employing a testimonial format were most effective. Additional mediation analysis showed that image-level negative emotionality partially mediated the relationship between PWM features and perceived effectiveness.

Conclusion

The effectiveness of graphic imagery, testimonials and images that elicit negative emotions provides guidance for researchers as well as for future implementation of more effective PWMs.
Acute abdomen secondary to nodular fat necrosis in a cat
Authors: Ortiz Victor , Cloup Emilie , Ortiz Ana
Published: October 2018

Nodular fat necrosis is a rare condition in the cat, and no cases of free‐floating abdominal masses in cats have been previously reported in the literature. Furthermore, nodular fat necrosis when present has not been associated with an acute abdomen presentation. An adult neutered female cat presented with acute abdomen. An exploratory laparotomy was performed identifying two free‐floating masses within the abdominal cavity of the patient. These masses were removed and the patient made an uneventful recovery. The histopathological analysis of the two free‐floating abdominal masses was consistent with a diagnosis of nodular fat necrosis. Acute abdomen is a rare presentation in the cat. When investigation highlights multiple abdominal masses without obvious communication with organs, nodular fat necrosis should be considered as a differential diagnosis. Surgical resection of these lesions was associated with a good outcome in this cat, with no signs of pain being present following surgical resection of the masses.