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Fulltext Ultrasound-assisted sequentially precipitated nickel-silica catalysts and its application in the partial hydrogenation of edible oil

Lim MSW, Yang TC, Tiong TJ, Pan GT, Chong S, Yap YH

Ultrason Sonochem, 2021 May;73:105490.
PMID: 33609992 DOI: 10.1016/j.ultsonch.2021.105490

Sequentially precipitated Mg-promoted nickel-silica catalysts with ageing performed under various ultrasonic intensities were employed to study the catalyst performance in the partial hydrogenation of sunflower oil. Results from various characterisation studies showed that increasing ultrasonic intensity caused a higher degree of hydroxycarbonate erosion and suppressed the formation of Ni silicates and silica support, which improved Ni dispersion, BET surface area and catalyst reducibility. Growth of silica clusters on the catalyst aggregates were observed in the absence of ultrasonication, which explained the higher silica and nickel silicate content on the outer surface of the catalyst particle. Application of ultrasound also altered the electron density of the Ni species, which led to higher activity and enhanced product selectivity for sonicated catalysts. The catalyst synthesised with ultrasonic intensity of 20.78 Wcm-2 achieved 22.6% increase in hydrogenation activity, along with 28.5% decrease in trans-C18:1 yield at IV = 70, thus supporting the feasibility of such technique.
Effects of sonication on co-precipitation synthesis and activity of copper manganese oxide catalyst to remove methane and sulphur dioxide gases

Yap YH, Lim MSW, Lee ZY, Lai KC, Jamaal MA, Wong FH, et al.

Ultrason Sonochem, 2018 Jan;40(Pt A):57-67.
PMID: 28946460 DOI: 10.1016/j.ultsonch.2017.06.032

The utilisation of ultrasound in chemical preparation has been the focus of intense study in various fields, including materials science and engineering. This paper presents a novel method of synthesising the copper-manganese oxide (Hopcalite) catalyst that is used for the removal of volatile organic compounds and greenhouse gases like carbon monoxide. Several samples prepared under different conditions, with and without ultrasound, were subjected to a series of characterisation tests such as XRD, BET, FE-SEM, EDX, TPR-H2, TGA and FT-IR in order to establish their chemical and physical properties. A series of catalytic tests using a micro-reactor were subsequently performed on the samples in order to substantiate the aforementioned properties by analysing their ability to oxidise compressed natural gas (CNG), containing methane and sulphur dioxide. Results showed that ultrasonic irradiation of the catalyst led to observable alterations in its morphology: surfaces of the particles were noticeably smoothed and an increased in amorphicity was detected. Furthermore, ultrasonic irradiation has shown to enhance the catalytic activity of Hopcalite, achieving a higher conversion of methane relative to non-sonicated samples. Varying the ultrasonic intensity also produced appreciable effects, whereby an increase in intensity results in a higher conversion rate. The catalyst sonicated at the highest intensity of 29.7W/cm2has a methane conversion rate of 13.5% at 400°C, which was the highest among all the samples tested.
Fulltext Propagating variational model uncertainty for bioacoustic call label smoothing

Rizos G, Lawson J, Mitchell S, Shah P, Wen X, Banks-Leite C, et al.

Patterns (N Y), 2024 Mar 08;5(3):100932.
PMID: 38487806 DOI: 10.1016/j.patter.2024.100932

Along with propagating the input toward making a prediction, Bayesian neural networks also propagate uncertainty. This has the potential to guide the training process by rejecting predictions of low confidence, and recent variational Bayesian methods can do so without Monte Carlo sampling of weights. Here, we apply sample-free methods for wildlife call detection on recordings made via passive acoustic monitoring equipment in the animals' natural habitats. We further propose uncertainty-aware label smoothing, where the smoothing probability is dependent on sample-free predictive uncertainty, in order to downweigh data samples that should contribute less to the loss value. We introduce a bioacoustic dataset recorded in Malaysian Borneo, containing overlapping calls from 30 species. On that dataset, our proposed method achieves an absolute percentage improvement of around 1.5 points on area under the receiver operating characteristic (AU-ROC), 13 points in F1, and 19.5 points in expected calibration error (ECE) compared to the point-estimate network baseline averaged across all target classes.
Heart Disease and Stroke Statistics-2019 Update: A Report From the American Heart Association

Benjamin EJ, Muntner P, Alonso A, Bittencourt MS, Callaway CW, Carson AP, et al.

Circulation, 2019 03 05;139(10):e56-e528.
PMID: 30700139 DOI: 10.1161/CIR.0000000000000659
Fulltext Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association

Tsao CW, Aday AW, Almarzooq ZI, Alonso A, Beaton AZ, Bittencourt MS, et al.

Circulation, 2022 Jan 26.
PMID: 35078371 DOI: 10.1161/CIR.0000000000001052

BACKGROUND: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).
METHODS: The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.
RESULTS: Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.
CONCLUSIONS: The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.
Fulltext Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

Virani SS, Alonso A, Aparicio HJ, Benjamin EJ, Bittencourt MS, Callaway CW, et al.

Circulation, 2021 Feb 23;143(8):e254-e743.
PMID: 33501848 DOI: 10.1161/CIR.0000000000000950

BACKGROUND: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).
METHODS: The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.
RESULTS: Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.
CONCLUSIONS: The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.
100 Questions in Livestock Helminthology Research

Morgan ER, Aziz NA, Blanchard A, Charlier J, Charvet C, Claerebout E, et al.

Trends Parasitol, 2019 01;35(1):52-71.
PMID: 30477758 DOI: 10.1016/j.pt.2018.10.006

An elicitation exercise was conducted to collect and identify pressing questions concerning the study of helminths in livestock, to help guide research priorities. Questions were invited from the research community in an inclusive way. Of 385 questions submitted, 100 were chosen by online vote, with priority given to open questions in important areas that are specific enough to permit investigation within a focused project or programme of research. The final list of questions was divided into ten themes. We present the questions and set them briefly in the context of the current state of knowledge. Although subjective, the results provide a snapshot of current concerns and perceived priorities in the field of livestock helminthology, and we hope that they will stimulate ongoing or new research efforts.
Thresholds for adding degraded tropical forest to the conservation estate

Ewers RM, Orme CDL, Pearse WD, Zulkifli N, Yvon-Durocher G, Yusah KM, et al.

Nature, 2024 Jul;631(8022):808-813.
PMID: 39020163 DOI: 10.1038/s41586-024-07657-w

Logged and disturbed forests are often viewed as degraded and depauperate environments compared with primary forest. However, they are dynamic ecosystems1 that provide refugia for large amounts of biodiversity2,3, so we cannot afford to underestimate their conservation value4. Here we present empirically defined thresholds for categorizing the conservation value of logged forests, using one of the most comprehensive assessments of taxon responses to habitat degradation in any tropical forest environment. We analysed the impact of logging intensity on the individual occurrence patterns of 1,681 taxa belonging to 86 taxonomic orders and 126 functional groups in Sabah, Malaysia. Our results demonstrate the existence of two conservation-relevant thresholds. First, lightly logged forests (<29% biomass removal) retain high conservation value and a largely intact functional composition, and are therefore likely to recover their pre-logging values if allowed to undergo natural regeneration. Second, the most extreme impacts occur in heavily degraded forests with more than two-thirds (>68%) of their biomass removed, and these are likely to require more expensive measures to recover their biodiversity value. Overall, our data confirm that primary forests are irreplaceable5, but they also reinforce the message that logged forests retain considerable conservation value that should not be overlooked.