33 research outputs found

    Examining wheat yield sensitivity to temperature and precipitation changes for a large ensemble of crop models using impact response surfaces

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    Impact response surfaces (IRSs) depict the response of an impact variable to changes in two explanatory variables as a plotted surface. Here, IRSs of spring and winter wheat yields were constructed from a 25-member ensemble of process-based crop simulation models. Twenty-one models were calibrated by different groups using a common set of calibration data, with calibrations applied independently to the same models in three cases. The sensitivity of modelled yield to changes in temperature and precipitation was tested by systematically modifying values of 1981-2010 baseline weather data to span the range of 19 changes projected for the late 21st century at three locations in Europe

    Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

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    Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

    Bioavailability of different iron amounts and speciations and EDTA-iron complexes for Emiliania huxleyi (Prymnesiophyceae)

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    The purpose of this study was to determine the effects of daily and/or initial additions of varying Fe(II) and Fe(III) amounts, in combination with or without EDTA, on Emiliania huxleyi cultures. Pertaining to this specific aim, the growth rate (µ), cell abundance (x104 cells L-1), total chl a concentration (µg L-1), chl a quota (pg cell -1), chl a:C ratio, Fe content (amol cell-1), Fe:C and Fe:chl a (pmol:ng) ratios, as well as pH values were observed. During the experiment, iron-free seawater was obtained by using a Chelex-100 column for iron-cleaning. The results revealed that the cell densities, growth rates, chlorophyll a concentrations, Fe contents, the calculated Fe:C ratios, and pH values were higher in the cultures containing 5000 nM Fe(III) ± EDTA than those of 5 nM Fe(III) and Fe(II). The growth rate, cell abundance, and total chl a concentration, on the other hand, were higher with daily additions of 5 nM Fe(II) instead of 5 nM Fe(III). Furthermore, cellular Fe quota was higher in the cultures with Fe(III). Cell abundance, chlorophyll a concentration and Fe:Chl a ratio were similar in 5 nM Fe(III)+ EDTA cultures (initially or daily added), possibly be due to the negative effects of EDTA on both. The growth rate, cell abundance, total chl a concentration, and Fe quota were higher in cultures with inorganic Fe(II) and Fe(III) contents, compared to those treated with EDTA containing Fe(II) and Fe(III). E. huxleyi cells seemed not to have used EDTA-bound iron, but their own released ligand to bind iron. Unexpectedly, while cellular iron content of cultures daily supplemented with Fe(II) was low, they exhibited the highest chl a content. The cell-chl a level was higher in daily supplemented cultures, with regard to those supported only initially with iron, evidencing the importance of continuous iron supply in chl a synthesis. © by PSP. 2007

    Optimization of Climatic Conditions Affecting Determination of the Amount of Water Needed by Plants in Relation to Their Life Cycle with Particle Swarm Optimization, and Determining the Optimum Irrigation Schedule

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    Plants' need for water has become a topic of research for the agriculture industry. The fact that plant species are very diverse and each plant's need for water varies makes it difficult to plan programs with conventional irrigation methods. Plants exhibit different stages from their seed time to harvest season. Each stage is defined within as days, and the amount of water needed by the plant throughout these stages varies. In this study, optimization of the irrigation schedule for each stage of a plant is provided. The amount of water needed by the plant was first figured out by using climatic data, and then, these values were recalculated in relation to the plant type. The amount of water needed at each stage was related to the plant type by using particle swarm optimization. The obtained results revealed the optimal irrigation schedule for each stage with the obtained data

    Sedation Practice Outside the Operating Room for Pediatric Gastrointestinal Endoscopy

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    Medical records of the 575 children who underwent gastrointestinal endoscopy outside the operating room were investigated retrospectively. The most frequently used combinations were propofol-midazolam-fentanyl in 83.2% of the procedures and propofol-midazolam in 13.8% of the procedures. 24 (3.4%) of 703 procedures had complications due to sedation anesthesia; 11 had hypoxia and 8 had pain in the injection area. Sedation anesthesia practice provided by an anesthesiologist outside the operating room enables gastrointestional endoscopic procedures to be carried out more safely

    Effects of climatic factors, drought risk and irrigation requirement on maize yield in the northeast farming region of China over 1961 to 2010

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    The Northeast Farming Region (NFR) is the most important and the largest rain-fed maize production region in China, accounting for 30% of China’s maize. We investigated the effects of climatic factors, drought risk and irrigation requirement on maize yield in different maize growth phases during 1961 to 2010 using a statistical analysis of observed yield from 44 stations in NFR. We divided the maize growing season into four growth phases, comprising seeding, vegetative, flowering and maturity. The dual crop coefficient was used to calculate crop evapotranspiration and soil water balance during the maize growing season. The effects of mean temperature, radiation, effective rainfall, water deficit, drought stress days, actual crop evapotranspiration (ETa) and irrigation requirement in different growth phases were included in the statistical model to predict maize yield. During the period 1961 to 2010, mean temperature increased significantly in all growth phases in NFR, while radiation decreased significantly in southern NFR in the seeding, vegetative and flowering phases. Effective rainfall increased in the seeding and vegetative phases leading to less water deficit, whereas decreased effective rainfall in the flowering and maturity phases enhanced water deficit. More days with drought stress were concentrated in western NFR where larger volumes of irrigation were needed. Our results indicate that the increase of mean temperature in the seeding and maturity phases was beneficial for maize yield, higher ETa in each growth phase would lead to yield increase, but too high rainfall would damage maize yield. The results also show that water deficit and drought stress days had significant negative effects on maize yield, and the absence of irrigation would manifest such effects on maize production in NFR. Therefore, the development of irrigation and drainage systems is highly needed for ensuring the stability of maize production in NFR. In addition, other adaptation measures like introducing new cultivars and optimizing soil and crop management to better conserve soil water would be beneficial for future maize production

    Transition Metal (II) Complexes with a Novel Azo-azomethine Schiff Base Ligand: Synthesis, Structural and Spectroscopic Characterization, Thermal Properties and Biological Applications

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    The pyrimidine based azo-linked Schiff base ligand, 5-benzoyl-1-((E)-(2-hydroxy-3-methoxy-5-((E)phenyldiazenyl)benzylidene)amino)-4-phenylpyrimidin-2(1H)-one (HL), and its transition metal (II) complexes were synthesized and defined by using H-1-NMR, C-13-NMR, Elemental analysis, FT-IR, MS, UV-vis, molar conductance, magnetic susceptibility and thermal analysis techniques. According to the conductance data obtained indicate all of the metal complexes have non-electrolytic nature. Square pyramidal geometry for Pd(II) and octahedral geometry for all the other complexes synthesized was concluded from the electronic absorption spectra and magnetic susceptibility measurements of the complexes. Investigation of the significant infrared bands of the active groups in the ligand and the solid complexes alludes that HL is coordinated to the metal ions ONO tridentate manner. Moreover, the absorption and emission properties of the azo-azomethine based ligand and its complexes were investigated. The results obtained show that fluorescence emissions of the ligand and its metal (II) complexes depend on the type of transition metal ions and the derivatives displayed moderate Stokes' shift values between 44 and 107 nm. All the compounds exhibited superb photostability. Further, antioxidant, antimicrobial and pBR322 plasmid DNA cleavage activities were investigated. All compounds showed good DPPH center dot (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity and complexes of [MnL2]center dot H2O and [NiL2]center dot H2O exhibited excellent metal chelating activity. All the compounds tested demonstrated two strand DNA cleavage activities
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