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  1. Xuwang Wei, Yang Yang, Jinfeng Ma
    Sains Malaysiana, 2017;46:2133-2142.
    CCUS (Carbon Capture, Utilization and Storage) now is a lead way to reduce greenhouse effect such as carbon dioxide emission in the world. This paper presents an integrated overview of seismic monitoring technology when CO2 injection process. Mainly is time-lapse seismic method .Time-lapse seismic method is a feasible way to monitor CO2 injection process when CO2 interaction with minerals, which is proved an effective method in CCUS experiments. AVAZ (Amplitude versus Azimuth) seismic method is proved a useful tool to indentify CO2 injection process, which can detect fluid-induced seismic anisotropic response and locating where CO2 flow to in reservoirs, therefore, it’s an effective way to monitor CO2 flow in CO2 monitoring process. Since we develop AVAZ modelling experiment base on rock physics theory to modeling the time-lapse AVAZ seismic reservoir response. The research show fluid saturation and pressure behave two main factors influence modeling seismic AVAZ response. Meanwhile the AVAZ response can also be detect by seismic AVAZ data.
  2. Lee YY, Abdul Halim Z
    PeerJ Comput Sci, 2020;6:e309.
    PMID: 33816960 DOI: 10.7717/peerj-cs.309
    Stochastic computing (SC) is an alternative computing domain for ubiquitous deterministic computing whereby a single logic gate can perform the arithmetic operation by exploiting the nature of probability math. SC was proposed in the 1960s when binary computing was expensive. However, presently, SC started to regain interest after the widespread of deep learning application, specifically the convolutional neural network (CNN) algorithm due to its practicality in hardware implementation. Although not all computing functions can translate to the SC domain, several useful function blocks related to the CNN algorithm had been proposed and tested by researchers. An evolution of CNN, namely, binarised neural network, had also gained attention in the edge computing due to its compactness and computing efficiency. This study reviews various SC CNN hardware implementation methodologies. Firstly, we review the fundamental concepts of SC and the circuit structure and then compare the advantages and disadvantages amongst different SC methods. Finally, we conclude the overview of SC in CNN and make suggestions for widespread implementation.
  3. Hu YG, Bachir Goudia Daoura, Iqbal Saeed, Quanhao Song, Yang Yang, Liang Chen
    Sains Malaysiana, 2018;47:235-242.
    The activities of key C4 photosynthetic enzymes including phosphoenolpyruvate carboxylase (PEPcase), NADP-malic
    enzyme (NADP-ME), malate dehydrogenase (MDH) and pyruvate phosphate dikinase (PPDK) were assayed in flag leaves
    at three major growth stages (heading, anthesis and grain filling) among 59 winter wheat genotypes grown in field
    conditions. All C4 enzymes expressed in the flag leaves and their activation showed a wide range of variation in relation
    to different growth stages in all the genotypes. PEPcase, NADP-ME and MDH displayed the highest mean activities of
    1.018, 0.758 and 0.731 µmol. min–1.mg–1 protein at heading stage, respectively; while PPDK showed the highest mean
    activity (0.888 µmol. min–1.mg–1 protein) at grain filling stage. The activities of PEPcase and PPDK were higher at
    heading stage, decreased at anthesis and again increased at grain filling stage, while NADP-ME and MDH exhibited a
    decreasing trend at the three stages. The results of the current study could be valuable and useful for wheat researchers
    in improving photosynthetic capacity of wheat.
  4. Lee YY, Halim ZA, Wahab MNA, Almohamad TA
    Research (Wash D C), 2024;7:0307.
    PMID: 38439995 DOI: 10.34133/research.0307
    Stochastic computing (SC) has a substantial amount of study on application-specific integrated circuit (ASIC) design for artificial intelligence (AI) edge computing, especially the convolutional neural network (CNN) algorithm. However, SC has little to no optimization on field-programmable gate array (FPGA). Scaling up the ASIC logic without FPGA-oriented designs is inefficient, while aggregating thousands of bitstreams is still challenging in the conventional SC. This research has reinvented several FPGA-efficient 8-bit SC CNN computing architectures, i.e., SC multiplexer multiply-accumulate, multiply-accumulate function generator, and binary rectified linear unit, and successfully scaled and implemented a fully parallel CNN model on Kintex7 FPGA. The proposed SC hardware only compromises 0.14% accuracy compared to binary computing on the handwriting Modified National Institute of Standards and Technology classification task and achieved at least 99.72% energy saving per image feedforward and 31× more data throughput than modern hardware. Unique to SC, early decision termination pushed the performance baseline exponentially with minimum accuracy loss, making SC CNN extremely lucrative for AI edge computing but limited to classification tasks. The SC's inherent noise heavily penalizes CNN regression performance, rendering SC unsuitable for regression tasks.
  5. Yang Y, Adnan HM, Alivi MA
    Heliyon, 2024 Nov 15;10(21):e39092.
    PMID: 39524767 DOI: 10.1016/j.heliyon.2024.e39092
    TikTok has become increasingly popular among young people in China and there is growing number of young people who start to pay great attention to their health through this platform. Wuhan is a significant location for this study, since it was the initial epicenter of COVID-19. However, little is known about the extent to which university students in Wuhan, China, rely on TikTok for health-related information and how this affects their preventive health actions in the post-COVID-19 era. Therefore, it is crucial to look into the direct effects of TikTok users' search for health information and their actions to protect their health, as well as the mediating functions of e-health literacy and COVID-19 risk perception. The impact of TikTok as a social media platform on the health-related behaviors of university students was examined using the Media Dependency Theory which explains how media use can have significant effects on individuals' attitudes, beliefs, and behaviors. 426 questionnaires were gathered by cluster sampling from a sample of Wuhan university students. Mplus8 was used to perform structural equation modelling, which looked at the relationships between these variables. The results showed a positive correlation between users' TikTok health information seeking and their health preventive behavior (β = 0.303, p 
  6. Zhang YY, Fan LL, Zheng FY, Zhao T, Rong JD, Chen LG, et al.
    Mitochondrial DNA B Resour, 2020 Feb 06;5(1):306-307.
    PMID: 33366532 DOI: 10.1080/23802359.2019.1702484
    Gigantochloa verticillata is produced in Mengla and Jinghong, Yunnan Province, China, and cultivated in Hong Kong. Vietnam, Thailand, India, Indonesia, and Malaysia are distributed and cultivated. We determined the complete chloroplast genome sequence for G. verticillata using Illumina sequencing data. The complete chloroplast sequence is 139,489 bp, including large single-copy (LSC) region of 83,062 bp, small single-copy (SSC) region of 12,877 bp, and a pair of invert repeats (IR) regions of 21,775 bp. Plastid genome contain 132 genes, 85 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. Phylogenetic analysis based on 23 chloroplast genomes indicates that G. verticillata is closely related to Dendrocalamus latiflorus in Bambusodae.
  7. Liu H, Ding Z, Fan Y, Luo Y, Yang Y
    Polymers (Basel), 2023 Sep 26;15(19).
    PMID: 37835940 DOI: 10.3390/polym15193892
    The bonding properties of BFRP composites have been demonstrated in previous studies, satisfying the strength and durability criteria. In this paper, a further in-depth study is carried out to bond Basalt Fibre Reinforced Polymer (BFRP) to Aluminum Alloy 5052 using two bonding agents, Aralite® 2012 and Aralite® 2015, respectively. The salt sprays under 80 °C, 3.5% NaCl environment; 80 °C, 5% NaCl environment; and pure water environment are also considered for comparison. Experimental results show that joints created with Araldite® 2012 adhesives show higher average breaking strength (10.66 MPa at 720 h) and better ductility in a 5% NaCl environment. While the Araldite® 2015 adhesive joint exhibits a combination of tear failure and interface failure, along with thin-layer cohesion failure. In the SEM images of the two adhesive joints' failure, fiber pullout due to tension and damage at the interface between fiber and resin is apparent. To validate the experimental outcomes, water absorption testing, DSC, TGA-DTG, and FTIR experiments were conducted on dog-bone-shaped adhesive specimens to elucidate the results.
  8. Ma S, Yang Y, Soh KG, Tan H
    BMC Public Health, 2024 Mar 06;24(1):727.
    PMID: 38448880 DOI: 10.1186/s12889-024-18097-6
    BACKGROUND: The physical and mental health of college students is often mentioned, but there is limited research on a direct relationship between the mental health status of college students and their physical fitness level. This study mainly proves the relationship between Chinese college students' mental health and physical fitness indicators.

    METHOD: This study collected SCL-90 Scale test results from 5262 students (4012 boys and 1250 girls) through a questionnaire survey and conducted a Sport Quality Test on these students. Statistical software SPSS was applied for differential analysis and logistic regression analysis. Specifically, the differences in sport quality indicators between normal and abnormal mean total scores of psychological tests were analyzed first. Then, the binary logistic regression model was used to explore the impacts of sports quality indicator scores on students' psychological fitness.

    RESULTS: There are differences in the results of physical fitness tests between students with abnormal psychology and students with normal psychology. The four indexes of students' vital capacity, speed, explosive power of lower limbs, and endurance running are effective in improving students' psychologically abnormal state, and endurance running and improving vital capacity are the most effective methods to improve students' psychologically abnormal state. In the physical tests of Chinese college students, the risk of psychological abnormalities was reduced by 9% for every one-point increase in lung capacity and 10.4% for every one-point increase in endurance running performance.

    CONCLUSIONS: Chinese college students' physical fitness and mental health are related. The best methods for treating psychological disorders are lung capacity improvement and endurance running. According to the physical test results of Chinese college students, for every 1-point increase in lung capacity and endurance running, the risk of psychological abnormalities decreased by 9% and 10.4%, respectively.

  9. Zhou B, Mui LG, Li J, Yang Y, Hu J
    Nurse Educ Pract, 2024 Feb;75:103874.
    PMID: 38244336 DOI: 10.1016/j.nepr.2024.103874
    AIM: To delineate the prevalence of smartphone addiction among nursing students. Further, to identify associated harms and underlying risk factors based on established theoretical models.

    BACKGROUND: Smartphones have become indispensable tools for students. However, excessive use can lead to smartphone addiction, causing physiological, psychological and social harm. Nursing students represent a unique population whose smartphone use may differ from other disciplines due to clinical training demands.

    METHODS: A scoping review was conducted following the Arksey and O'Malley framework. Seven databases were systematically searched from inception to August 2023. Inclusion criteria encompassed original research on smartphone addiction, harms and risks among nursing students. Data were extracted and thematically synthesized.

    RESULTS: Studies (n=39) met inclusion criteria, representing 15 countries. Rates of smartphone addiction among nursing students ranged from 19% to 72%, averaging 40-50%. Incorporated into Engel's biopsychosocial models, the harm is emphasized across individual inclinations, emotional aspects, cognitive processes and executive functions. Physiological harms include sleep disruption, vision concerns,other physiological concerns. psychologically, addiction correlated with increased anxiety and depression,decline in self-esteem, learning and attention and other psychological concerns. socially, it encompasses harms such as interpersonal relationships challenges, career development and decline in social abilities. The I-PACE model identifies various risk factors for smartphone addiction among nursing students, including personal factors such as interpersonal relationship anxiety and perceived academic pressure, affective factors like high stress and learning burnout, cognitive factors such as the need for online social interaction and low perception of social support, as well as executive factors like extended usage duration, poor self-control and usage before sleep.

    CONCLUSION: Smartphone addiction among nursing students presents tangible harms. A proposed theoretical model integrating established frameworks provides avenues to better comprehend addiction genesis and potential intervention strategies. Given addiction's multi-factorial nature, future research investigating harm mitigation through optimizing predisposing, precipitating and perpetuating factors is warranted.

  10. Gao F, Huang JF, Zheng KI, Pan XY, Ma HL, Liu WY, et al.
    J Gastroenterol Hepatol, 2020 Oct;35(10):1804-1812.
    PMID: 32246876 DOI: 10.1111/jgh.15055
    BACKGROUND AND AIM: There is an immediate need for non-invasive accurate tests for diagnosing liver fibrosis in patients with non-alcoholic steatohepatitis (NASH). Previously, it has been suggested that MACK-3 (a formula that combines homeostasis model assessment-insulin resistance with serum serum aspartate aminotransferase and cytokeratin [CK]18-M30 levels) accurately identifies patients with fibrotic NASH. Our aim was to assess the performance of MACK-3 and develop a novel, non-invasive algorithm for diagnosing fibrotic NASH.

    METHODS: Six hundred and thirty-six adults with biopsy-proven non-alcoholic fatty liver disease (NAFLD) from two independent Asian cohorts were enrolled in our study. Liver stiffness measurement (LSM) was assessed by vibration-controlled transient elastography (Fibroscan). Fibrotic NASH was defined as NASH with a NAFLD activity score (NAS) ≥ 4 and F ≥ 2 fibrosis.

    RESULTS: Metabolic syndrome (MetS), platelet count and MACK-3 were independent predictors of fibrotic NASH. On the basis of their regression coefficients, we developed a novel nomogram showing a good discriminatory ability (area under receiver operating characteristic curve [AUROC]: 0.79, 95% confidence interval [CI 0.75-0.83]) and a high negative predictive value (NPV: 94.7%) to rule out fibrotic NASH. In the validation set, this nomogram had a higher AUROC (0.81, 95%CI 0.74-0.87) than that of MACK-3 (AUROC: 0.75, 95%CI 0.68-0.82; P 

  11. Liu X, Yu X, Yang Y, Heeb S, Gao S, Chan KG, et al.
    Appl Microbiol Biotechnol, 2018 Apr;102(8):3711-3721.
    PMID: 29511844 DOI: 10.1007/s00253-018-8857-0
    The antibiotic pyrrolnitrin (PRN) is a tryptophan-derived secondary metabolite that plays an important role in the biocontrol of plant diseases due to its broad-spectrum of antimicrobial activities. The PRN biosynthetic gene cluster remains to be characterised in Serratia plymuthica, though it is highly conserved in PRN-producing bacteria. To better understand PRN biosynthesis and its regulation in Serratia, the prnABCD operon from S. plymuthica G3 was cloned, sequenced and expressed in Escherichia coli DH5α. Furthermore, an engineered strain prnind which is a conditional mutant of G3 prnABCD under the control of the Ptac promoter was constructed. This mutant was able to overproduce PRN with isopropylthiogalactoside (IPTG) induction by overexpressing prnABCD, whilst behaving as a conditional mutant of G3 prnABCD in the absence of IPTG. These results confirmed that prnABCD is responsible for PRN biosynthesis in strain G3. Further experiments involving lux-/dsRed-based promoter fusions, combined with site-directed mutagenesis of the putative σS extended -10 region in the prnA promoter, and liquid chromatography-mass spectrometry (LC-MS) analysis extended our previous knowledge about G3, revealing that quorum sensing (QS) regulates PRN biosynthesis through cross talk with RpoS, which may directly activated prnABCD transcription. These findings suggest that PRN in S. plymuthica G3 is produced in a tightly controlled manner, and has diverse functions, such as modulation of cell motility, in addition to antimicrobial activities. Meanwhile, the construction of inducible mutants could be a powerful tool to improve PRN production, beyond its potential use for the investigation of the biological function of PRN.
  12. Jiang H, Bai L, Ji L, Bai Z, Su J, Qin T, et al.
    J Virol, 2020 07 16;94(15).
    PMID: 32461319 DOI: 10.1128/JVI.00294-20
    Japanese encephalitis virus (JEV) infection alters microRNA (miRNA) expression in the central nervous system (CNS). However, the mechanism contributing to miRNA regulation in the CNS is not known. We discovered global degradation of mature miRNA in mouse brains and neuroblastoma (NA) cells after JEV infection. Integrative analysis of miRNAs and mRNAs suggested that several significantly downregulated miRNAs and their targeted mRNAs were clustered into an inflammation pathway. Transfection with miRNA 466d-3p (miR-466d-3p) decreased interleukin-1β (IL-1β) expression and inhibited JEV replication in NA cells. However, miR-466d-3p expression increased after JEV infection in the presence of cycloheximide, indicating that viral protein expression reduced miR-466d-3p expression. We generated all the JEV coding proteins and demonstrated NS3 helicase protein to be a potent miRNA suppressor. The NS3 proteins of Zika virus, West Nile virus, and dengue virus serotype 1 (DENV-1) and DENV-2 also decreased miR-466d-3p expression. Results from helicase-blocking assays and in vitro unwinding assays demonstrated that NS3 could unwind pre-miR-466d and induce miRNA dysfunction. Computational models and an RNA immunoprecipitation assay revealed arginine-rich domains of NS3 to be crucial for pre-miRNA binding and degradation of host miRNAs. Importantly, site-directed mutagenesis of conserved residues in NS3 revealed that R226G and R202W reduced the binding affinity and degradation of pre-miR-466d. These results expand the function of flavivirus helicases beyond unwinding duplex RNA to degrade pre-miRNAs. Hence, we revealed a new mechanism for NS3 in regulating miRNA pathways and promoting neuroinflammation.IMPORTANCE Host miRNAs have been reported to regulate JEV-induced inflammation in the CNS. We found that JEV infection could reduce expression of host miRNA. The helicase region of the NS3 protein bound specifically to miRNA precursors and could lead to incorrect unwinding of miRNA precursors, thereby reducing the expression of mature miRNAs. This observation led to two major findings. First, our results suggested that JEV NS3 protein induced miR-466d-3p degradation, which promoted IL-1β expression and JEV replication. Second, arginine molecules on NS3 were the main miRNA-binding sites, because we demonstrated that miRNA degradation was abolished if arginines at R226 and R202 were mutated. Our study provides new insights into the molecular mechanism of JEV and reveals several amino acid sites that could be mutated for a JEV vaccine.
  13. Yang Y, Zhang Z, Zhang L, Song F, Ren Y, Zhang X, et al.
    Sci Total Environ, 2023 Aug 01;884:163741.
    PMID: 37120025 DOI: 10.1016/j.scitotenv.2023.163741
    Wood-based panels provide efficient alternatives to materials such as plastics derived from traditional petroleum sources and thereby help to mitigate greenhouse gas emissions. Unfortunately, using indoor manufactured panel products also results in significant emissions of volatile organic compounds including olefins, aromatic and ester compounds, which negatively affect human health. This paper highlights recent developments and notable achievements in the field of indoor hazardous air treatment technologies to guide future research toward environmentally friendly and economically feasible directions that may have a significant impact on the improvement of human settlements. Summarizing and synthesizing the principles, advantages, and limitations of different technologies can assist policymakers and engineers in identifying the most appropriate technology for a particular air pollution control program based on criteria such as cost-effectiveness, efficiency, and environmental impact. In addition, insights into the development of indoor air pollution control technologies are provided and potential areas for innovation, improvement of existing technologies, and development of new technologies are identified. Finally, the authors also hope that this sub-paper will raise public awareness of indoor air pollution issues and promote a better understanding of the importance of indoor air pollution control technologies for public health, environmental protection, and sustainable development.
  14. Toh TH, Qi YY, Yong SM, Lee JS, Liyana NF, See RY, et al.
    Hum Vaccin Immunother, 2023 Dec 31;19(1):2167438.
    PMID: 36705277 DOI: 10.1080/21645515.2023.2167438
    The effectiveness of the vero cell inactivated vaccine (CoronaVac®) against severe acute respiratory infection (‎SARI)‎ caused by SARS-CoV-2 in the real world was assessed. A matched test-negative case-control design was employed using the web-based national information system, as well as the hospitalization dataset in Sibu Hospital. Vaccine effectiveness was measured by conditional logistic regression with adjustment for gender, underlying comorbidity, smoking status, and education level. Between 15 March and 30 September 2021, 838 eligible SARI patients were identified from the hospitalization records. Vaccine effectiveness was 42.4% (95% confidence interval [CI]: -28.3 to 74.1) for partial vaccination (after receiving the first dose to 14 days after receiving the second dose), and 76.5% (95% CI: 45.6 to 89.8) for complete vaccination (at 15 days or more after receiving the second dose). This analysis indicated that two doses of CoronaVac® vaccine provided efficacious protection against SARI caused by SARS-CoV-2 in the short term. However, the duration of protection, and performance against new variants need to be studied continuously.
  15. Song Z, Zhang W, Jiang Q, Deng L, Du L, Mou W, et al.
    Int J Surg, 2023 Dec 01;109(12):3848-3860.
    PMID: 37988414 DOI: 10.1097/JS9.0000000000000862
    BACKGROUND: The early detection of high-grade prostate cancer (HGPCa) is of great importance. However, the current detection strategies result in a high rate of negative biopsies and high medical costs. In this study, the authors aimed to establish an Asian Prostate Cancer Artificial intelligence (APCA) score with no extra cost other than routine health check-ups to predict the risk of HGPCa.

    PATIENTS AND METHODS: A total of 7476 patients with routine health check-up data who underwent prostate biopsies from January 2008 to December 2021 in eight referral centres in Asia were screened. After data pre-processing and cleaning, 5037 patients and 117 features were analyzed. Seven AI-based algorithms were tested for feature selection and seven AI-based algorithms were tested for classification, with the best combination applied for model construction. The APAC score was established in the CH cohort and validated in a multi-centre cohort and in each validation cohort to evaluate its generalizability in different Asian regions. The performance of the models was evaluated using area under the receiver operating characteristic curve (ROC), calibration plot, and decision curve analyses.

    RESULTS: Eighteen features were involved in the APCA score predicting HGPCa, with some of these markers not previously used in prostate cancer diagnosis. The area under the curve (AUC) was 0.76 (95% CI:0.74-0.78) in the multi-centre validation cohort and the increment of AUC (APCA vs. PSA) was 0.16 (95% CI:0.13-0.20). The calibration plots yielded a high degree of coherence and the decision curve analysis yielded a higher net clinical benefit. Applying the APCA score could reduce unnecessary biopsies by 20.2% and 38.4%, at the risk of missing 5.0% and 10.0% of HGPCa cases in the multi-centre validation cohort, respectively.

    CONCLUSIONS: The APCA score based on routine health check-ups could reduce unnecessary prostate biopsies without additional examinations in Asian populations. Further prospective population-based studies are warranted to confirm these results.

  16. Wang H, Liddell CA, Coates MM, Mooney MD, Levitz CE, Schumacher AE, et al.
    Lancet, 2014 Sep 13;384(9947):957-79.
    PMID: 24797572 DOI: 10.1016/S0140-6736(14)60497-9
    BACKGROUND: Remarkable financial and political efforts have been focused on the reduction of child mortality during the past few decades. Timely measurements of levels and trends in under-5 mortality are important to assess progress towards the Millennium Development Goal 4 (MDG 4) target of reduction of child mortality by two thirds from 1990 to 2015, and to identify models of success.

    METHODS: We generated updated estimates of child mortality in early neonatal (age 0-6 days), late neonatal (7-28 days), postneonatal (29-364 days), childhood (1-4 years), and under-5 (0-4 years) age groups for 188 countries from 1970 to 2013, with more than 29,000 survey, census, vital registration, and sample registration datapoints. We used Gaussian process regression with adjustments for bias and non-sampling error to synthesise the data for under-5 mortality for each country, and a separate model to estimate mortality for more detailed age groups. We used explanatory mixed effects regression models to assess the association between under-5 mortality and income per person, maternal education, HIV child death rates, secular shifts, and other factors. To quantify the contribution of these different factors and birth numbers to the change in numbers of deaths in under-5 age groups from 1990 to 2013, we used Shapley decomposition. We used estimated rates of change between 2000 and 2013 to construct under-5 mortality rate scenarios out to 2030.

    FINDINGS: We estimated that 6·3 million (95% UI 6·0-6·6) children under-5 died in 2013, a 64% reduction from 17·6 million (17·1-18·1) in 1970. In 2013, child mortality rates ranged from 152·5 per 1000 livebirths (130·6-177·4) in Guinea-Bissau to 2·3 (1·8-2·9) per 1000 in Singapore. The annualised rates of change from 1990 to 2013 ranged from -6·8% to 0·1%. 99 of 188 countries, including 43 of 48 countries in sub-Saharan Africa, had faster decreases in child mortality during 2000-13 than during 1990-2000. In 2013, neonatal deaths accounted for 41·6% of under-5 deaths compared with 37·4% in 1990. Compared with 1990, in 2013, rising numbers of births, especially in sub-Saharan Africa, led to 1·4 million more child deaths, and rising income per person and maternal education led to 0·9 million and 2·2 million fewer deaths, respectively. Changes in secular trends led to 4·2 million fewer deaths. Unexplained factors accounted for only -1% of the change in child deaths. In 30 developing countries, decreases since 2000 have been faster than predicted attributable to income, education, and secular shift alone.

    INTERPRETATION: Only 27 developing countries are expected to achieve MDG 4. Decreases since 2000 in under-5 mortality rates are accelerating in many developing countries, especially in sub-Saharan Africa. The Millennium Declaration and increased development assistance for health might have been a factor in faster decreases in some developing countries. Without further accelerated progress, many countries in west and central Africa will still have high levels of under-5 mortality in 2030.

    FUNDING: Bill & Melinda Gates Foundation, US Agency for International Development.

  17. Kassebaum NJ, Bertozzi-Villa A, Coggeshall MS, Shackelford KA, Steiner C, Heuton KR, et al.
    Lancet, 2014 Sep 13;384(9947):980-1004.
    PMID: 24797575 DOI: 10.1016/S0140-6736(14)60696-6
    BACKGROUND: The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100,000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery.

    METHODS: We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61 sources from a systematic review and 943 site-years of vital registration data. We also did a systematic review of reports about the timing of maternal death, identifying 142 sources to use in our analysis. We developed estimates for each country for 1990-2013 using Bayesian meta-regression. We estimated 95% uncertainty intervals (UIs) for all values.

    FINDINGS: 292,982 (95% UI 261,017-327,792) maternal deaths occurred in 2013, compared with 376,034 (343,483-407,574) in 1990. The global annual rate of change in the MMR was -0·3% (-1·1 to 0·6) from 1990 to 2003, and -2·7% (-3·9 to -1·5) from 2003 to 2013, with evidence of continued acceleration. MMRs reduced consistently in south, east, and southeast Asia between 1990 and 2013, but maternal deaths increased in much of sub-Saharan Africa during the 1990s. 2070 (1290-2866) maternal deaths were related to HIV in 2013, 0·4% (0·2-0·6) of the global total. MMR was highest in the oldest age groups in both 1990 and 2013. In 2013, most deaths occurred intrapartum or postpartum. Causes varied by region and between 1990 and 2013. We recorded substantial variation in the MMR by country in 2013, from 956·8 (685·1-1262·8) in South Sudan to 2·4 (1·6-3·6) in Iceland.

    INTERPRETATION: Global rates of change suggest that only 16 countries will achieve the MDG 5 target by 2015. Accelerated reductions since the Millennium Declaration in 2000 coincide with increased development assistance for maternal, newborn, and child health. Setting of targets and associated interventions for after 2015 will need careful consideration of regions that are making slow progress, such as west and central Africa.

    FUNDING: Bill & Melinda Gates Foundation.

  18. Murray CJ, Ortblad KF, Guinovart C, Lim SS, Wolock TM, Roberts DA, et al.
    Lancet, 2014 Sep 13;384(9947):1005-70.
    PMID: 25059949 DOI: 10.1016/S0140-6736(14)60844-8
    BACKGROUND: The Millennium Declaration in 2000 brought special global attention to HIV, tuberculosis, and malaria through the formulation of Millennium Development Goal (MDG) 6. The Global Burden of Disease 2013 study provides a consistent and comprehensive approach to disease estimation for between 1990 and 2013, and an opportunity to assess whether accelerated progress has occured since the Millennium Declaration.

    METHODS: To estimate incidence and mortality for HIV, we used the UNAIDS Spectrum model appropriately modified based on a systematic review of available studies of mortality with and without antiretroviral therapy (ART). For concentrated epidemics, we calibrated Spectrum models to fit vital registration data corrected for misclassification of HIV deaths. In generalised epidemics, we minimised a loss function to select epidemic curves most consistent with prevalence data and demographic data for all-cause mortality. We analysed counterfactual scenarios for HIV to assess years of life saved through prevention of mother-to-child transmission (PMTCT) and ART. For tuberculosis, we analysed vital registration and verbal autopsy data to estimate mortality using cause of death ensemble modelling. We analysed data for corrected case-notifications, expert opinions on the case-detection rate, prevalence surveys, and estimated cause-specific mortality using Bayesian meta-regression to generate consistent trends in all parameters. We analysed malaria mortality and incidence using an updated cause of death database, a systematic analysis of verbal autopsy validation studies for malaria, and recent studies (2010-13) of incidence, drug resistance, and coverage of insecticide-treated bednets.

    FINDINGS: Globally in 2013, there were 1·8 million new HIV infections (95% uncertainty interval 1·7 million to 2·1 million), 29·2 million prevalent HIV cases (28·1 to 31·7), and 1·3 million HIV deaths (1·3 to 1·5). At the peak of the epidemic in 2005, HIV caused 1·7 million deaths (1·6 million to 1·9 million). Concentrated epidemics in Latin America and eastern Europe are substantially smaller than previously estimated. Through interventions including PMTCT and ART, 19·1 million life-years (16·6 million to 21·5 million) have been saved, 70·3% (65·4 to 76·1) in developing countries. From 2000 to 2011, the ratio of development assistance for health for HIV to years of life saved through intervention was US$4498 in developing countries. Including in HIV-positive individuals, all-form tuberculosis incidence was 7·5 million (7·4 million to 7·7 million), prevalence was 11·9 million (11·6 million to 12·2 million), and number of deaths was 1·4 million (1·3 million to 1·5 million) in 2013. In the same year and in only individuals who were HIV-negative, all-form tuberculosis incidence was 7·1 million (6·9 million to 7·3 million), prevalence was 11·2 million (10·8 million to 11·6 million), and number of deaths was 1·3 million (1·2 million to 1·4 million). Annualised rates of change (ARC) for incidence, prevalence, and death became negative after 2000. Tuberculosis in HIV-negative individuals disproportionately occurs in men and boys (versus women and girls); 64·0% of cases (63·6 to 64·3) and 64·7% of deaths (60·8 to 70·3). Globally, malaria cases and deaths grew rapidly from 1990 reaching a peak of 232 million cases (143 million to 387 million) in 2003 and 1·2 million deaths (1·1 million to 1·4 million) in 2004. Since 2004, child deaths from malaria in sub-Saharan Africa have decreased by 31·5% (15·7 to 44·1). Outside of Africa, malaria mortality has been steadily decreasing since 1990.

    INTERPRETATION: Our estimates of the number of people living with HIV are 18·7% smaller than UNAIDS's estimates in 2012. The number of people living with malaria is larger than estimated by WHO. The number of people living with HIV, tuberculosis, or malaria have all decreased since 2000. At the global level, upward trends for malaria and HIV deaths have been reversed and declines in tuberculosis deaths have accelerated. 101 countries (74 of which are developing) still have increasing HIV incidence. Substantial progress since the Millennium Declaration is an encouraging sign of the effect of global action.

    FUNDING: Bill & Melinda Gates Foundation.

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