Windowed Fourier transform of two-dimensional quaternionic signals

In this paper, we generalize the classical windowed Fourier transform (WFT) to quaternion-\ud valued signals, called the quaternionic windowed Fourier transform (QWFT). Using\ud the spectral representation of the quaternionic Fourier transform (QFT), we derive several\ud important properties such as reconstruction formula, reproducing kernel, isometry, and\ud orthogonality relation. Taking the Gaussian function as window function we obtain quaternionic\ud Gabor filters which play the role of coefficient functions when decomposing\ud the signal in the quaternionic Gabor basis. We apply the QWFT properties and the\ud (right-sided) QFT to establish a Heisenberg type uncertainty principle for the QWFT.\ud Finally, we briefly introduce an application of the QWFT to a linear time-varying system

Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background: Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods: The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings: Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation: Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions. Funding: Bill & Melinda Gates Foundation

Dynamic simulation and control of an industrial surfactant reactor

This case study investigates the behaviour of a semi-batch surfactant reactor and seeks ways to improve the reactor's operating efficiency through the use of automatic control. The reaction involves adding ethylene oxide (EO) to nonylphenol to form oligomer (short chain polymer) with the assistance of potassium hydroxide acting as catalyst. The reactor was modelled using dynamic mass and energy balances plus a description of the kinetics of nonylphenol polyethoxylation. The pressure in reactor was calculated by applying Wilson's equation and the heat transfer coefficient of the heat exchanger was determined from plant data. The model was implemented in SPEEDUP flowsheeting package, and able to predict the length of oligomers in the reactor at any time. The model has been tested and compared with the performance of the actual plant. Due to the nature of the semi-batch reactor, it is difficult to manually operate at a fixed optimal condition. Therefore, an improved automatic control scheme is needed to maintain the system as close as possible to its optimum condition. This was investigated by using the model and was found to offer higher output from the reactor

Two Drosophila receptor-like tyrosine phosphatase genes are expressed in a subset of developing axons and pioneer neurons in the embryonic CNS

Cell674661-673CELL

Experimental intoxication by the leaves of Melia azedarach (Meliaceae) in cattle Intoxicação experimental pelas folhas de Melia azedarach (Meliaceae) em bovinos

Green leaves of Melia azedarach were administered at single doses ranging from 5 to 30 g/kg bw to 11 calves. Clinical signs were depression, ruminal stasis, dry feces with blood, ataxia, muscle tremors, sternal recumbency, hypothermia and abdominal pain. Serum AST and CPK were increased. Signs appeared from 8 to 24 hours after dosing, and the clinical course lasted from 2 to 72 hours. Three calves dosed with 30g/kg bw died. The macroscopic findings included intestinal congestion, yellow discoloration of the liver, brain congestion and dry feces with blood in the rectum. The liver showed swollen and vacuolated hepatocytes. Necrotic hepatocytes were scattered throughout the parenchyma or concentrated in the periacinar zone. Degenerative and necrotic changes were observed in the epithelium of the forestomachs. There was also necrosis of the lymphoid tissue. Skeletal muscles showed hyaline degeneration and fiber necrosis. The necrotic fragments contained floccular or granular debris with infiltration by macrophages and satellite cells.<br>Folhas verdes de Melia azedarach foram administradas em dose única a 11 bovinos nas doses de 5 a 30g/kg de peso vivo. Os sinais clínicos caracterizaram-se por depressão, atonia ruminal, fezes duras com sangue, incoordenação, tremores musculares, decúbito esternal, hipotermia e dores abdominais. Os níveis séricos de AST e CPK estavam aumentados. O aparecimento dos sinais clínicos foi observado entre 8-24 horas após a ingestão das folhas e o curso clínico durou entre 2 e 72 horas. Três animais que receberam 30g/kg morreram. Os achados macroscópicos caracterizaram-se por congestão dos intestinos e do cérebro, fígado amarelado e presença de fezes duras com sangue no reto. Os hepatócitos estavam tumefeitos e com vacuolização citoplasmática. Observaram-se hepatócitos necróticos distribuídos no parênquima ou próximos à veia centrolobular. Lesões degenerativas e necróticas foram observadas no epitélio dos pré-estômagos. Havia também necrose do tecido linfóide. Nos músculos esqueléticos observaram-se degeneração hialina e necrose das fibras. Os fragmentos necróticos apresentavam necrose flocular ou granular com infiltração de macrófagos e células satélites