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From grid to field: Assessing quality of gridded weather data for agricultural applications
No full textAbstractHigh quality measured weather data (MWD) are not available in many agricultural regions across the globe. As a result, many studies that dealt with global climate change, land use, and food security scenarios and emerging agricultural decision support tools have relied on gridded weather data (GWD) to estimate crop phenology and crop yields. An issue is the agreement of GWD with MWD and the degree to which this agreement may influence the utility of GWD for agricultural research. The objectives of this study were: (i) to compare the agreement of two widely used gridded weather databases (GWDs) (Daymet and PRISM) and MWD, (ii) to evaluate their robustness at simulating maize growth and development, and (iii) to examine how GWD compare relative to weather data interpolated from existing meteorological stations for which MWD are available. The U.S. Corn Belt, a region that accounts for 43 and 34% of respective global maize and soybean production, was used as a case of study because of its dense weather station network and high-quality MWD. Historical daily MWD were retrieved from 45 locations across the region, resulting in ca. 1300 site-years. To test the accuracy of GWDs, separate simulations of maize yield and development were performed, separately for the two GWDs and MWD, using a well-validated maize crop model. For both GWDs, small biases were observed for temperature and growing degree-days in relation with MWD. However, accuracy was much lower for relative humidity, precipitation, reference evapotranspiration, and degree of seasonal water deficit. There was close agreement in duration of vegetative and reproductive phases between GWD and MWD, with root mean square error (RMSE) ranging from 3 to 7days for the different crop phases and GWDs. However, robustness of GWDs to reproduce maize yields simulated using MWD was lower as indicated by the RMSE (18 and 24% of average yield for Daymet and PRISM, respectively). There was also a high proportion of site-years (20 and 32% for Daymet and PRISM, respectively) exhibiting a yield deviation >15% in relation to the yield simulated using MWD. Data interpolation using a dense weather station network resulted in lower RMSE% for simulated phenology and yields relative to GWDs. Findings from this study indicate that GWD cannot replace MWD as a basis for field-scale agricultural applications. While GWD appear to be robust for applications that only require temperature for prediction of crop stages, GWD should not be used for applications that depend on accurate estimation of crop water balance, crop growth, and yield. We propose that the evaluation performed in this study should be taken as a routinary activity for any research or agricultural decision tool that relies on GWD
BundleMAP: Anatomically localized classification, regression, and hypothesis testing in diffusion MRI
No full textAbstractDiffusion MRI (dMRI) provides rich information on the white matter of the human brain, enabling insight into neurological disease, normal aging, and neuroplasticity. We present BundleMAP, an approach to extracting features from dMRI data that can be used for supervised classification, regression, and hypothesis testing. Our features are based on aggregating measurements along nerve fiber bundles, enabling visualization and anatomical interpretation. The main idea behind BundleMAP is to use the ISOMAP manifold learning technique to jointly parametrize nerve fiber bundles. We combine this idea with mechanisms for outlier removal and feature selection to obtain a practical machine learning pipeline. We demonstrate that it increases accuracy of disease detection and estimation of disease activity, and that it improves the power of statistical tests
Elastofibroma dorsi: Clinical evaluation of 61 cases and review of the literature
No full textAbstractObjectiveElastofibroma dorsi (ED) is a rare, benign, soft tissue tumor typically located between inferior corner of scapula and posterior chest wall causing mass, scapular snapping, and pain. When classic symptoms and localization are present, it is diagnosed without biopsy and treated with marginal resection. This study retrospectively analyzed patients operated on for ED to evaluate presenting symptoms, tumor size, complications, and clinical results, and to suggest optimal treatments.MethodsThis study included 51 patients who underwent surgery for ED in 2 different clinics between 2005 and 2015. Patient age, gender, profession, side affected, symptoms, average duration of symptoms, and tumor size were researched. Radiological examinations of patients were evaluated. Patients with lesions larger than 5 cm in size were operated on. Postoperative complications, recurrence, and functional results were evaluated using Constant score and compared to preoperative values.ResultsA total of 61 operated lesions of 51 patients clinically and radiologically diagnosed with ED were retrospectively evaluated. Average length of time patient experienced symptoms was 11.21 months. Lesions in 19 (37.2%) patients were bilateral, 10 of which were symptomatic and larger than 5 cm in size, meeting indication for surgery. Average lesion diameter was 8.7 cm. Average follow-up was 26.89 months. Average of preoperative Constant score of 67.28 subsequently increased to 92.88 (p < 0.05). Seroma and hematoma were observed in 11.5% of patients.ConclusionGenerally, good clinical results can be obtained with marginal resection without requiring a biopsy, considering classic complaints and radiological appearance of ED.Level of evidenceLevel IV, Therapeutic study
Comprehensive multiphysics modeling of photocatalytic processes by computational fluid dynamics based on intrinsic kinetic parameters determined in a differential photoreactor
No full textAbstractThis work describes the procedure for the simulation of the operation of a photocatalytic reactor by using a multiphysics computational fluid dynamics (CFD) model based on the determination of the intrinsic kinetics parameters in an optically differential photoreactor. The model includes the rigorous description of the hydrodynamics, radiation transfer, mass transport and chemical reaction rate based on a mechanistic kinetic model. Possible existence of dead and recirculation zones has been identified from the flow field, showing a non-uniform flow through the reactor domain. The theoretical laminar profile is not reached due to the short length of the annular core and the departure from the ideal models has been quantified. The predicted velocity field has been experimentally validated with good agreement by injecting a tracer. The radiation field was simulated for slurry TiO2 suspensions with concentrations between 0.005 and 5g·L−1, showing an optimum catalyst loading around 0.1–0.2g·L−1. Above this value, the increase in the absorption of radiation is negligible, whereas a more non-uniform radiation profile develops, keeping the most external regions of the reactor in the dark. The results of photocatalytic activity, using methanol oxidation as test reaction, showed good agreement between model predictions and experimental data, with errors between 2% and 10% depending on the catalyst concentration. The successful validation confirms not only the scientific background of the model, but also supports its applicability for engineering purposes in the design and optimization of large scale photocatalytic reactor to overcome some of limitations hindering the industrial development of this technology
Secukinumab shows significant efficacy in palmoplantar psoriasis: Results from GESTURE, a randomized controlled trial
No full textBackgroundPlaque psoriasis affecting palms and soles is disabling and often resistant to treatment.ObjectiveEvaluate the efficacy and safety of secukinumab, an anti-interleukin 17A antibody, in subjects with palmoplantar psoriasis.MethodsIn this double-blinded, randomized controlled trial, 205 subjects were randomized 1:1:1 to secukinumab 300 mg, 150 mg, or placebo. The primary endpoint was Palmoplantar Investigator's Global Assessment (ppIGA) 0 (clear) or 1 (almost clear/minimal) response at week 16.ResultsAt week 16, the percentage of subjects who achieved clear or almost clear palms and soles (or ppIGA 0/1) with secukinumab 300 mg (33.3%) and 150 mg (22.1%) was superior to the percentage achieved with placebo (1.5%, P < .001). Palmoplantar Psoriasis Area and Severity Index (ppPASI) was significantly reduced with secukinumab 300 mg (−54.5%) and 150 mg (−35.3%) compared with placebo (−4.0%, P < .001). Dermatology Life Quality Index (DLQI) 0/1 responses from subjects in the secukinumab groups were also significantly higher compared with placebo at week 16 (P < .01) and pain and function of palms and soles was markedly improved with secukinumab as measured by the palmoplantar Quality-of-Life Instrument. Secukinumab 300 mg consistently showed the best outcomes. The safety profile was favorable and similar to previous studies.LimitationsLack of active comparator.ConclusionIn GESTURE, the largest randomized controlled trial in palmoplantar psoriasis, secukinumab demonstrated the greatest efficacy to date for treating difficult-to-treat psoriasis
Detection of minor and trace elements in powdered milk
No full textAbstractPassive gamma ray spectrometry and neutron capture prompt gamma activation analysis (PGAA) were used to investigate powdered cow's milk samples [termed optimal (1), optimal (2) and optimal (3)] collected from local markets in the city of Cairo, Egypt. Standard material with a total average activity of 0.830±0.2μCi and a certified reference material [IAEA (A-14)] were used to study the accuracy of a passive multi-gamma ray measurement method. Three powdered milk samples of the same geometry and volume were used in this analysis. The specific activity of 226Ra ranged from 24.5±2.1 to 114±1.2Bq/kg, 232Th from 8±1 to 14±1.2Bq/kg and 40K from 444±28 to 1826.1±3.1Bq/kg, all of which were higher than the activities corresponding to the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR) (50, 50 and 500Bq/kg for 226Ra, 232Th and 40K, respectively). The average dose rate at 1cm for 40K ranged from 8.21E−02±0.12 to 3.3E−1±0.22mSv/h/cm. We also showed that 208Tl81, 212Pb82 and 212Bi83 should be considered products of thorium. k0-PGAA was carried out using an integrated and calibrated prompt gamma ray system with a neutron flux of 106n/cm2 per second. The thermal to epithermal neutron flux ratio (f) and cadmium ratio were measured using a thin gold foil technique (ration=160). Different Cl concentrations were prepared as standards for k0-PGAA. The elemental concentrations of Na, Mg, Al, Ca, Mn, Fe, Cu, Ga, Zn, As, Se, Cs, Cd, In, Th and I were measured in the three powdered milk samples. The mean±standard deviation ranges of the elements were as follows: Na=1069±49–1583±53ppm, Mg=347±13.64–385±16.71ppm, Al=45±1.30–72±2.40ppm, Fe=5500±110–7123±130ppm, Zn=107±3–123±6ppm, Ca=4200±72–5483±81ppm, Mn=1269±69–1784±72ppm, Pr=1.7±0.02–2.6±0.07ppm, Ga=265±5–293±8ppm, Cu=57±0.5–64±0.9ppm, In=1000± 38.64–1574±41.34ppm, Cd=6.1±2.71–12.6±4.11ppm, I=53±0.09–62±1.18ppm, Cs=4±1.56–11±4.22ppm, As=26±0.66–29±0.89ppm, Se=126±4.8–144±5.7ppm, Th=47±1.0–78±6.0ppm
Preparation, characterization and catalytic activity of WO3 supported on sulfated tin oxide catalysts
No full textAbstractSolid acid catalysts of 15wt.%SO4/SnO2 loaded with 5–45wt.%WO3 were prepared, calcined at 400–800°C, and then characterized by TG–DTA, XRD, FT-IR spectra and nitrogen adsorption techniques. The surface acidity was determined by potentiometric titration with n-butylamine in acetonitrile and FT-IR spectra of chemisorbed pyridine.The presence of sulfate ions together with WO3 hindered the crystallization of tin oxide and the products at a lower temperature of ⩽500°C found amorphous. The crystallinity of tin oxide increased with raising the calcination temperature to provide nanocrystalline cassiterite structure, whereas, increasing WO3 loading up to 25wt.% decreases the process. Careful control of calcination temperature and WO3 loading was found to have a critical effect on the specific surface area and therefore on the resulted surface acidity.The surface acidity measurements indicate that the catalysts possess very strong acid sites that designate both of Brønsted and Lewis acid sites.Catalytic application toward esterification of propionic acid with n-butanol was tested and the effect of various parameters, i.e., reaction temperature, reactant molar ratio, weight of the catalyst, WO3 loading and calcination temperature was also investigated. The highest conversion level was found for products loaded with 25wt.%WO3 and calcined at 400°C. Although both of Brønsted and Lewis acid sites are responsible for the reaction, the former acid sites found more effective on catalyzing the esterification reaction
Biomarker of exposure level data set in smokers switching from conventional cigarettes to Tobacco Heating System 2.2, continuing smoking or abstaining from smoking for 5 days
No full textAbstractLevels of biomarkers of exposure to selected harmful and potentially harmful smoke constituents found in cigarette smoke, in addition to nicotine were measured in 160 smokers randomized for 5 days to continuing smoking conventional cigarettes (41 participants), switching to Tobacco Heating System 2.2 (THS 2.2) (80 participants), or abstaining from smoking (39 participants). The data reported here are descriptive statistics of the levels of each biomarker of exposure expressed as concentrations adjusted to creatinine; at baseline, and at the end of the study, and their relative change from baseline. Reductions in the levels of biomarkers of exposure when expressed as quantity excreted, are also reported. Detailed descriptions of bioanalytical assays used are also provided. The data presented here are related to the article entitled “Evaluation of the Tobacco Heating System 2.2. Part 8: 5-Day randomized reduced exposure clinical study in Poland” (Haziza et al., 2016) [1]
Alpha-ketoglutarate protects Streptomyces coelicolor from visible light-induced phototoxicity
No full textAbstractIt has been known that some Streptomyces species, including the model strain Streptomyces coelicolor, are vulnerable to visible light. Much evidence demonstrated that the phototoxicity induced by visible light is a consequence of the formation of intracellular reactive oxygen species (ROS), which are potentially harmful to cells. In this study, we found that α-ketoglutarate (α-KG) has a protective role against the phototoxicity in S. coelicolor. It could be because that α-KG can detoxify the ROS with the concomitant formation of succinate, which mediates the cells getting into anaerobiosis to produce more NADH and maintain intracellular redox homeostasis, a situation that was demonstrated by overexpressing gdhA in S. coelicolor. This finding, therefore, connects the central metabolites with the bacterial resistance against phototoxicity effect induced by visible light