Differentiable Physics-based Greenhouse Simulation

We present a differentiable greenhouse simulation model based on physical processes whose parameters can be obtained by training from real data. The physics-based simulation model is fully interpretable and is able to do state prediction for both climate and crop dynamics in the greenhouse over very a long time horizon. The model works by constructing a system of linear differential equations and solving them to obtain the next state. We propose a procedure to solve the differential equations, handle the problem of missing unobservable states in the data, and train the model efficiently. Our experiment shows the procedure is effective. The model improves significantly after training and can simulate a greenhouse that grows cucumbers accurately.Comment: Accepted at the Machine Learning and the Physical Sciences workshop, NeurIPS 2022. 7 pages, 2 figure

A comprehensive evaluation of polygenic score and genotype imputation performances of human SNP arrays in diverse populations

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Study of the Correlation Between Bronchial Hyperresponsiveness and Exhaled Nitric Oxide in Subjects with Suspected Symptoms of Asthma

Background: Bronchial hyperresponsiveness (BHR) is one of main features of asthma within chronic inflammation and reversible bronchoconstriction. Actually, methacholine challenge is useful method to detect BHR in subjects with suspected asthma symptoms. However, this method has some limitations due to its safety and side effects. The measure of exhaled nitric oxide (NO) demonstrates currently as the alternative method for methacholine challenge. Methods: Ninety-five subjects had at least one of the following symptoms were included in this study: wheezing or chest tightness during exercise, chronic cough, or nocturnal coughing. They were divided into two groups depending on the positivity or negativity of BHR. Lung function test, exhaled NO measurement, and methacholine challenge were done for each study subject. Results: There were no significant differences between two groups for age and male/female ratio (41 ± 22 vs 38 ± 23 years old and 0.9 vs 1.1; P > 0.05 and P > 0.05; respectively). The percentage of wheezing and nocturnal coughing in subjects with positive BHR (BHR+) was significantly higher than that in subjects with negative BHR (BHR-: 70.9% and 64.5% vs 31.2% and 45.1%; P<0.001 and P<0.01; respectively). FENO measured at 50 mL/s in subjects with BHR+ was significantly higher subjects with BHR- (36 ± 10 ppb vs 11 ± 9 ppb; P<0.001). There was a significant correlation between FENO-50 mL/s and methacholine dose in subjects with BHR+ (R= -0.695; P<0.001). FENO-50 mL/s at 35 ppb had 86.7% of sensibility and 82.9% of specificity for diagnosis of BHR. Conclusion: FENO is a useful biomarker for diagnosis of asthma in subjects with suspected symptoms of asthma. FENO level has a high sensitivity and specificity for screening out subjects with BHR. The measurement of exhaled NO may be an alternative method for detecting BHR in diagnosis of asthma in clinical practice

Synthesis and Photocatalytic Activity for Toluene Removal of CDs/TiO2 - Zeolite Y

Hydrothermally synthesized carbon nanodots (CDs) were impregnated on TiO2. The product (CDs/TiO2) was mechanically mixed with zeolite Y for application in toluene photocatalytic oxidation reaction under UV radiation. Material properties of the samples were investigated by different methods. Toluene vapor was chosen as a typical volatile organic compound to investigate the performance of CDs/TiO2 – zeolite Y photocatalyst when these technological parameters were changed: toluene concentration, gas flow rate, humidity and UV light intensity. In each reaction, only one parameter was changed and the remaining conditions were fixed. The toluene concentrations at the beginning and the end of each reaction were analyzed with the use of gas chromatography (GC). The results of different reaction conditions show the trends for toluene treatment of the CDs/TiO2 – zeolite Y catalyst, thereby providing specific explanations for these trends. The experiments also show that toluene removal is highest when the toluene concentration in the inlet gas is 314 ppmv, the flow rate is 3 L/h, the humidity is 60%, and the catalyst (CDs/TiO2 – zeolite Y composite with 70% zeolite in weight) is illuminated by 4 UV lamps. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Fabrication and hardness of in-situ Al3Ti–Al2O3 composite

In this work, an in-situ Al3Ti–Al2O3 composite was optimally synthesized from raw powders via mechanical milling and conventional sintering processes. The strong influence of milling time on the promotion of the phase reaction between the initial TiO2 and Al materials was proven by using X-ray diffraction and surface morphology analysis. The obtained results showed that the milling process did not initiate any reaction between the raw TiO2 and Al materials. However, the milling process was important for creating a homogeneous powder mixture and refining the particle size of the powders. The Al3Ti–Al2O3 composites were completely formed after conventional sintering at 750°C for 30 min for a milling time of over 4 h. The highest obtained microhardness of the composite was approximately 130 HV, which was suggested to be related to the microstructure of the bulk composite specimen consisting of two main phases, the Al3Ti matrix and the Al2O3 particles dispersed in the matrix. A small portion of an unidentified phase, a Ti-rich compound, was found in the matrix together with a tiny fraction of AlTi3. We suggest that the optimal sintering process and mechanical milling are important key factors in fabricating bulk hardness Al3Ti–Al2O3 composite materials

Secular trend, seasonality and effects of a community-based intervention on neonatal mortality: follow-up of a cluster-randomised trial in Quang Ninh province, Vietnam.

BACKGROUND: Little is know about whether the effects of community engagement interventions for child survival in low-income and middle-income settings are sustained. Seasonal variation and secular trend may blur the data. Neonatal mortality was reduced in a cluster-randomised trial in Vietnam where laywomen facilitated groups composed of local stakeholders employing a problem-solving approach for 3 years. In this analysis, we aim at disentangling the secular trend, the seasonal variation and the effect of the intervention on neonatal mortality during and after the trial. METHODS: In Quang Ninh province, 44 communes were allocated to intervention and 46 to control. Births and neonatal deaths were assessed in a baseline survey in 2005, monitored during the trial in 2008-2011 and followed up by a survey in 2014. Time series analyses were performed on monthly neonatal mortality data. RESULTS: There were 30 187 live births and 480 neonatal deaths. The intervention reduced the neonatal mortality from 19.1 to 11.6 per 1000 live births. The reduction was sustained 3 years after the trial. The control areas reached a similar level at the time of follow-up. Time series decomposition analysis revealed a downward trend in the intervention areas during the trial that was not found in the control areas. Neonatal mortality peaked in the hot and wet summers. CONCLUSIONS: A community engagement intervention resulted in a lower neonatal mortality rate that was sustained but not further reduced after the end of the trial. When decomposing time series of neonatal mortality, a clear downward trend was demonstrated in intervention but not in control areas. TRIAL REGISTRATION NUMBER: ISRCTN44599712, Post-results