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Fulltext Enhancing the Performance of Piezoelectric Wind Energy Harvester Using Curve-Shaped Attachments on the Bluff Body

Poudel P, Sharma S, Ansari MNM, Vaish R, Kumar R, Ibrahim SM, et al.

Glob Chall, 2023 Apr;7(4):2100140.
PMID: 37020619 DOI: 10.1002/gch2.202100140

This paper presents a piezoelectric wind energy harvester that operates by a galloping mechanism with different shaped attachments attached to a bluff body. A comparison is made between harvesters that consist of different shaped attachments on a bluff body; these include triangular, circular, square, Y-shaped, and curve-shaped attachments. Simulation of the pressure field and the velocity field variation around the different shaped bluff bodies is performed and it is found that a high pressure difference creates a high lift force on the bluff body with curve-shaped attachments. A theoretical model based on a galloping mechanism is presented, which is verified by experiments. It is observed that the proposed harvester with curve-shaped attachments provides the best performance, where the harvester with a curve-shaped attachments provides the highest voltage and power output compared to the other shaped harvesters examined in this study. This paper provides a new concept for improving the power performance of the piezoelectric wind energy harvesters with modifications made on the bluff body.
Spatiotemporal nexus between vegetation change and extreme climatic indices and their possible causes of change

Islam ARMT, Islam HMT, Shahid S, Khatun MK, Ali MM, Rahman MS, et al.

J Environ Manage, 2021 Jul 01;289:112505.
PMID: 33819656 DOI: 10.1016/j.jenvman.2021.112505

Climate extremes have a significant impact on vegetation. However, little is known about vegetation response to climatic extremes in Bangladesh. The association of Normalized Difference Vegetation Index (NDVI) with nine extreme precipitation and temperature indices was evaluated to identify the nexus between vegetation and climatic extremes and their associations in Bangladesh for the period 1986-2017. Moreover, detrended fluctuation analysis (DFA) and Morlet wavelet analysis (MWA) were employed to evaluate the possible future trends and decipher the existing periodic cycles, respectively in the time series of NDVI and climate extremes. Besides, atmospheric variables of ECMWF ERA5 were used to examine the casual circulation mechanism responsible for climatic extremes of Bangladesh. The results revealed that the monthly NDVI is positively associated with extreme rainfall with spatiotemporal heterogeneity. Warm temperature indices showed a significant negative association with NDVI on the seasonal scale, while precipitation and cold temperature extremes showed a positive association with yearly NDVI. The DEA revealed a continuous increase in temperature extreme in the future, while no change in precipitation extremes. NDVI also revealed a significant association with extreme temperature indices with a time lag of one month and with precipitation extreme without time lag. Spatial analysis indicated insensitivity of marshy vegetation type to climate extremes in winter. The study revealed that elevated summer geopotential height, no visible anticyclonic center, reduced high cloud cover, and low solar radiation with higher humidity contributed to climatic extremes in Bangladesh. The nexus between NDVI and climatic extremes established in this study indicated that increasing warm temperature extremes due to global warming might have severe implications on Bangladesh's ecology and the environment in the future.
Fulltext Preparation of Lignan-Rich Extract from the Aerial Parts of Phyllanthus niruri Using Nonconventional Methods

Meselhy MR, Abdel-Sattar OE, El-Mekkawy S, El-Desoky AM, Mohamed SO, Mohsen SM, et al.

Molecules, 2020 Mar 05;25(5).
PMID: 32151037 DOI: 10.3390/molecules25051179

Phyllanthin and related lignans were found to be responsible, at least in part, for most of the activity of Phyllanthus species. This observation encouraged the authors to develop methods for the preparation of an extract rich in phyllanthin and related lignans from the aerial parts of P. niruri L. Direct extraction with solvents produced extracts with variable yields and contents of lignans. Lignans were identified by LC-ESI-MS analysis as phyllanthin (used as marker substance), hypophyllanthin, phylltetralin, nirtetralin, and niranthin. Extraction with boiling water produced 18.10 g% (w/w) extract with a trace amount of lignans (phyllanthin content of 0.33 ± 0.10 mg/g extract), while extraction with MeOH gave 3.6 g% w/w extract with a low phyllanthin content (3.1 mg/g extract), as determined by HPLC. However, Soxhlet extraction with hexane, CH2Cl2, or acetone gave extracts with low yields (0.82, 1.12, and 3.40 g% w/w, respectively) and a higher phyllanthin contents (36.2 ± 2.6, 11.7 ± 1.68, and 11.7 ± 1.10 mg/g extract, respectively). Extraction quality and efficiency were optimized by adopting the following three different approaches: (1) Alkaline digestion of the plant material with 30% potassium hydroxide yielded 3.1 g% w/w of purified extract with high phyllanthin content (22.34 ± 0.13 mg/g); (2) microwave-assisted extraction using 80% MeOH gave an extract with a better yield (8.13 g% w/w) and phyllanthin content (21.2 ± 1.30 mg/g) (after filtration through a Diaion HP-20 column); and (3) treatment of the ground plant material at 50 °C with two hydrolytic enzymes, cellulase (9 U/g for 12 h) and then, protease (4 U/g up to 72 h) optimized the yield of extract (13.92 g% w/w) and phyllanthin content (25.9 mg/g extract and total lignans content of 85.87 mg/g extract). In conclusion, the nonconventional methods presented here are superior for optimizing the yield of extract and its lignan contents from the aerial parts of P. niruri.
A critical review and prospect of NO2 and SO2 pollution over Asia: Hotspots, trends, and sources

Jion MMMF, Jannat JN, Mia MY, Ali MA, Islam MS, Ibrahim SM, et al.

Sci Total Environ, 2023 Mar 13;876:162851.
PMID: 36921864 DOI: 10.1016/j.scitotenv.2023.162851

Nitrogen dioxide (NO2) and sulfur dioxide (SO2) are two major atmospheric pollutants that significantly threaten human health, the environment, and ecosystems worldwide. Despite this, only some studies have investigated the spatiotemporal hotspots of NO2 and SO2, their trends, production, and sources in Asia. Our study presents a literature review covering the production, trends, and sources of NO2 and SO2 across Asian countries (e.g., Bangladesh, China, India, Iran, Japan, Pakistan, Malaysia, Kuwait, and Nepal). Based on the findings of the review, NO2 and SO2 pollution are increasing due to industrial activity, fossil fuel burning, biomass burning, heavy traffic movement, electricity generation, and power plants. There is significant concern about health risks associated with NO2 and SO2 emissions in Bangladesh, China, India, Malaysia, and Iran, as they pay less attention to managing and controlling pollution. Even though the lack of quality datasets and adequate research in most Asian countries further complicates the management and control of NO2 and SO2 pollution. This study has NO2 and SO2 pollution scenarios, including hotspots, trends, sources, and their influences on Asian countries. This study highlights the existing research gaps and recommends new research on identifying integrated sources, their variations, spatiotemporal trends, emission characteristics, and pollution level. Finally, the present study suggests a framework for controlling and monitoring these two pollutants' emissions.
Fulltext 2021 Asian Pacific Society of Cardiology Consensus Recommendations on the Use of P2Y12 Receptor Antagonists in the Asia-Pacific Region: Special Populations

Tan JWC, Chew DP, Tsui KL, Tan D, Duplyakov D, Hammoudeh A, et al.

Eur Cardiol, 2021 Feb;16:e43.
PMID: 34815751 DOI: 10.15420/ecr.2021.35

Advanced age, diabetes, and chronic kidney disease not only increase the risk for ischaemic events in chronic coronary syndromes (CCS) but also confer a high bleeding risk during antiplatelet therapy. These special populations may warrant modification of therapy, especially among Asians, who have displayed characteristics that are clinically distinct from Western patients. Previous guidance has been provided regarding the classification of high-risk CCS and the use of newer-generation P2Y12 inhibitors (i.e. ticagrelor and prasugrel) after acute coronary syndromes (ACS) in Asia. The authors summarise evidence on the use of these P2Y12 inhibitors during the transition from ACS to CCS and among special populations. Specifically, they present recommendations on the roles of standard dual antiplatelet therapy, shortened dual antiplatelet therapy and single antiplatelet therapy among patients with coronary artery disease, who are either transitioning from ACS to CCS; elderly; or with chronic kidney disease, diabetes, multivessel coronary artery disease and bleeding events during therapy.
Clinical Features, Socioeconomic Status, Management, and Outcomes of Acute Heart Failure: PEACE MENA Registry Phase I Results

AlBackr H, Alhabib KF, Sulaiman K, Jamee A, Sobhy M, Benkhedda S, et al.

Curr Vasc Pharmacol, 2023;21(4):257-267.
PMID: 37231723 DOI: 10.2174/1570161121666230525111259

INTRODUCTION: PEACE MENA (Program for the Evaluation and Management of Cardiac Events in the Middle East and North Africa) is a prospective registry in Arab countries for in-patients with acute myocardial infarction (AMI) or acute heart failure (AHF). Here, we report the baseline characteristics and outcomes of in-patients with AHF who were enrolled during the first 14 months of the recruitment phase.
METHODS: A prospective, multi-centre, multi-country study including patients hospitalized with AHF was conducted. Clinical characteristics, echocardiogram, BNP (B-type natriuretic peptide), socioeconomic status, management, 1-month, and 1-year outcomes are reported.
RESULTS: Between April 2019 and June 2020, a total of 1258 adults with AHF from 16 Arab countries were recruited. Their mean age was 63.3 (±15) years, 56.8% were men, 65% had monthly income ≤US$ 500, and 56% had limited education. Furthermore, 55% had diabetes mellitus, 67% had hypertension; 55% had HFrEF (heart failure with reduced ejection fraction), and 19% had HFpEF (heart failure with preserved ejection fraction). At 1 year, 3.6% had a heart failure-related device (0-22%) and 7.3% used an angiotensin receptor neprilysin inhibitor (0-43%). Mortality was 4.4% per 1 month and 11.77% per 1-year post-discharge. Compared with higher-income patients, lower-income patients had a higher 1-year total heart failure hospitalization rate (45.6 vs 29.9%, p=0.001), and the 1-year mortality difference was not statistically significant (13.2 vs 8.8%, p=0.059).
CONCLUSION: Most of the patients with AHF in Arab countries had a high burden of cardiac risk factors, low income, and low education status with great heterogeneity in key performance indicators of AHF management among Arab countries.
Fulltext Clinical features, socioeconomic status, management, short and long-term outcomes of patients with acute myocardial infarction: Phase I results of PEACE MENA registry

Al Saleh A, Jamee A, Sulaiman K, Sobhy M, Gamra H, Alkindi F, et al.

PLoS One, 2024;19(1):e0296056.
PMID: 38206951 DOI: 10.1371/journal.pone.0296056

BACKGROUND: The Program for the Evaluation and Management of Cardiac Events in the Middle East and North Africa (PEACE MENA) is a prospective registry program in Arabian countries that involves in patients with acute myocardial infarction (AMI) or acute heart failure (AHF).
METHODS: This prospective, multi-center, multi-country study is the first report of the baseline characteristics and outcomes of inpatients with AMI who were enrolled during the first 14-month recruitment phase. We report the clinical characteristics, socioeconomic, educational levels, and management, in-hospital, one month and one-year outcomes.
RESULTS: Between April 2019 and June 2020, 1377 patients with AMI were enrolled (79.1% males) from 16 Arabian countries. The mean age (± SD) was 58 ± 12 years. Almost half of the population had a net income < $500/month, and 40% had limited education. Nearly half of the cohort had a history of diabetes mellitus, hypertension, or hypercholesterolemia; 53% had STEMI, and almost half (49.7%) underwent a primary percutaneous intervention (PCI) (lowest 4.5% and highest 100%). Thrombolytics were used by 36.2%. (Lowest 6.45% and highest (90.9%). No reperfusion occurred in 13.8% of patients (lowest was 0% and highest 72.7%).Primary PCI was performed less frequently in the lower income group vs. high income group (26.3% vs. 54.7%; P<0.001). Recurrent ischemia occurred more frequently in the low-income group (10.9% vs. 7%; P = 0.018). Re-admission occurred in 9% at 1 month and 30% at 1 year, whereas 1-month mortality was 0.7% and 1-year mortality 4.7%.
CONCLUSION: In the MENA region, patients with AMI present at a young age and have a high burden of cardiac risk factors. Most of the patients in the registry have a low income and low educational status. There is heterogeneity among key performance indicators of AMI management among various Arabian countries.