Empirical evaluation of confidence and prediction intervals for spatial models of forest structu
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英语作文对比评价语Title: Comparative Evaluation of English Essays。
In the realm of English composition, assessing and contrasting essays involves a meticulous examination of various aspects such as structure, coherence, language proficiency, and argumentative prowess. This comparative evaluation aims to dissect two distinct essays without divulging the prompt provided.Essay A。
Strengths:1. Structural Coherence: Essay A demonstrates a clear and logical structure, with each paragraph seamlessly transitioning to the next. The introduction sets the stage by providing context and a succinct thesis statement, followed by well-developed body paragraphs that support the main argument. The conclusion effectively summarizes keypoints without introducing new information.2. Language Proficiency: The language used in Essay A is sophisticated and appropriate for the intended audience. The writer employs a diverse vocabulary, varied sentence structures, and precise terminology to convey ideas effectively. Moreover, the essay showcases a strong command of grammar and mechanics, enhancing readability.3. Argumentative Depth: This essay excels in presentinga nuanced argument supported by relevant evidence and analysis. Each claim is substantiated with examples, quotations, or data, demonstrating thorough research and critical thinking skills. Additionally, the writer anticipates counterarguments and addresses them thoughtfully, further strengthening the overall argumentative framework.Weaknesses:1. Lack of Originality: While Essay A effectively synthesizes existing research and opinions, it lacksoriginal insights or unique perspectives. The arguments presented are somewhat conventional and fail to offer innovative solutions or fresh interpretations of the topic.2. Limited Engagement: Despite its coherent structure and well-developed arguments, Essay A could benefit from deeper engagement with opposing viewpoints or alternative perspectives. The writer tends to prioritize supporting evidence that aligns with their thesis, potentially overlooking contradictory evidence that could enrich the discourse.Essay B。
Master Your Data to Get to the Answer, View Results with Ease and ConfidenceUsing TripleTOF® Technology and MasterView™ Software to Quickly Identify Unknown Compounds André Schreiber and David CoxAB SCIEX Concord, Ontario (Canada)OverviewHere we present results using a novel data processing approachto quickly and automatically identify unknown and unexpectedcompounds, such as residues and contaminants, in complexfood samples. The data analysis workflow combines non-targetpeak finding, sample-control-comparison, empirical formulafinding, MS/MS library searching, and ChemSpider searchcombined with MS/MS interpretation – and most of these stepsare automated, making data processing fast and easy for theuser. Food samples were prepared using a simple solventextraction or QuEChERS extraction and analyzed with reversedphase LC. High resolution and accurate mass MS and MS/MSinformation was collected in a single injection on AB SCIEXTripleTOF® 4600 and 5600 systems. Data were processed usingthe new MasterView™ software.IntroductionLC-MS/MS is a powerful analytical tool for the analysis of food residues and contaminants. In particular, triple quadrupole based mass analyzers are popular for targeted quantitation of hundreds of food contaminants in a single analysis because of their extra degree of selectivity and sensitivity when operated in Multiple Reaction Monitoring (MRM) mode.Advancements in LC-MS/MS technology, including hybrid systems like triple quadruple linear ion trap (QTRAP®) and quadrupole-quadrupole Time-of-Flight (TripleTOF®), now provide the ability to perform both targeted and non-targeted screening in food samples on a routine basis. However, full scan chromatograms are very rich in information and contain easily thousands of ions from both chemical compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore the high resolution and accurate mass data generated to get answers and results from these complex data.MasterView™ software utilizes a powerful non-target peak finding algorithm to find chromatographic features. Sample-control-comparison was performed to separate matrix and sample-specific signals from true contaminations. Ions of interest were processed using automatic MS/MS library searching, empirical formula finding, and ChemSpider searching to tentatively identify the molecular formula and structure of the unknown compound. The accurate mass MS/MS information was utilized to reduce the number of potential formulae during the formula finding step and to compare the experimentalMS/MS pattern with a theoretical fragmentation pattern of structures proposed by ChemSpider.The new MasterView™ software offers an intuitive workflow to tentatively identify unexpected compounds in complex samples. The software allows quick processing, easy results review, and reporting.Experimental•Food samples from a local supermarket. Organic produce was used for sample-control-comparison.•QuEChERS extraction of fruit and vegetable samples following guideline EN 15662/2007 using commercialQuEChERS kits and solvent extraction of cereal samplesusing acetonitrile/water (80/20) + 1% formic acid•5-20x dilution of sample extracts to minimize possible matrix effects•UHPLC using a Shimadzu UFLC XR system with Restek Ultra Aqueous C18 (100 x 2.1 mm) 3 µm column•Gradient of water and methanol with 10 mM ammonium formate at a flow rate of 0.5 mL/min and injection volume of10 µL•AB SCIEX TripleTOF® 4600 and 5600 system with DuoSpray™ source operated in ESI mode•Continuous recalibration between injections using the Calibrant Delivery System (CDS)•Information Dependent Acquisition (IDA) using a TOF-MS survey scan 100-1000 Da (100 ms) and up to 10 or 20dependent TOF-MS/MS scans 50-1000 Da (100 ms) using Collision Energy (CE) of 35 V with Collision Energy Spread (CES) of ± 15 V•Dynamic background subtraction (DBS) was activated for best IDA coverage, no inclusion list was used to allow unknownidentification without the need for a second injection to acquire MS/MS dataLC-MS/MS data were processed using the new MasterView™ software version 1.0.Results and DiscussionTripleTOF® System Performance CharacteristicsResolution > 20,000 (at full width half height) and mass accuracy <5 ppm are often sufficient to separate the analytes of interest from interfering matrices and, thus, are identified as the set requirements for compound identification in various guidelines.1, 2 The TripleTOF® 4600 and 5600 system provides resolving power of up to 35,000 and 40,000, respectively, dependent on the mass detected and stable mass accuracy of ~2 ppm at fast acquisition speed in MS and MS/MS mode.3, 4Data Analysis Workflow for Non-Targeted ScreeningExtracted Ion Chromatograms (XIC) are generated using a non-target peak finding algorithm. Sample-control-comparison is used to differentiate matrix and sample specific signals from true contaminations. High resolution and accurate mass MS andMS/MS data are used to automatically calculate matching molecular formulae. Formulae are searched against ChemSpider to find matching structures. The theoretical fragmentation pattern of these structures is automatically compared with the experimental MS/MS pattern to rank confidence in identification. In addition, all acquired MS/MS spectra are searched against available MS/MS spectral libraries to identify compounds present in these libraries. AB SCIEX offers true MS/MS spectral libraries for over 2500 compounds, including pesticides, toxins, pharmaceuticals, veterinary drugs, and drugs of abuse.Figure 1.Data analysis workflow for non-targeted screening inMasterView™ software, XIC are generated by a non-target peak findingalgorithms and sample-control-comparison is used to identify relevant chromatographic features, empirical formula finding, ChemSpidersearching and MS/MS information is used to tentatively identifycompoundsNon-Target Identification in MasterView™ Software1.Open data files and select contaminated and controlsample.Evaluation of TOF-MS (Formula Finder)Evaluation of TOF-MS/MS (Search)MS MS/MS TIC of Sample and ControlNon-T arget XIC Generation and Sample-Control-ComparisonSample ControlTICFormula C15H17N3OCl2üüMS/MSüControl sampleSample2. Define parameters for peak finding, formula finding, andlibrary searching. Start processing by clicking ‘Process’.MasterView™ software will now automatically find peaks,compare signal intensity and perform formula finding and library searching. This can take several minutes depending on samples’ complexity and processing settings. For example, the complete processing of two QuEChERS extracts took ~8:30 min (using a Win7, 64 bit, 4 core, 8 GB memory computer).3. Review results using ‘traffic lights’ and display of MS andMS/MS spectra.4. Review details of formula finding and MS/MS librarysearching. The hyperlink of the molecular formula starts a ChemSpider search and MS/MS interpretation.5.Review ChemSpider search results. The theoretical MS/MSpattern is automatically compared with the experimentalMS/MS spectrum and ranked by a confidence score. Thepredicted structure of a selected product ion is highlighted in the structure display to allow result evaluation.Control sampleSampleControl sampleSampleControl sampleSampleEmpirical Formula Finding AlgorithmMasterView™ software automatically uses the accurate mass MS and MS/MS to automatically predict possible molecular formulae. Details on the formula finding algorithm are illustrated in Figure 2.Figure 2. Empirical formula finding – mass accuracy and isotope pattern are used to calculate possible molecular formulae, theoretical MS/MS fragments are calculated and compared against to TOF-MS/MS spectrum to reduce the list of matching formulae, finally the software algorithm finds other adducts to predict the correct molecular formula of the uncharged species, C 12H 6N 2O 2F 2 ranked highest in the combined MS and MS/MS scoreCombining all available accurate mass MS and MS/MSinformation is crucial to minimize the list of potential formulae. Figure 3 and Table 1 illustrate that the number of formulae can be reduced from over 100 to a single match by not only using the accurate mass of the molecular ion but also including isotope pattern matching and MS/MS evaluation. The formula finding algorithm also checks for possible adducts to predict the correct molecular formula of the uncharged species.The molecular ion shown in Figure 2 was identified as anM+NH 4+ion based on the presence of 4 additional ions.Figure 3. Number of matching molecular formulae depending on the information used for empirical formula finding (elements allowed C 100H 200N 10O 10S 5F 5Cl 5Br 5)Table 1. Ranking of found formulae using MS and MS/MS information, the MS rank combines mass accuracy and isotope pattern matching and the MS/MS rank combines mass accuracy and number of ions (n) Hit Formula MS Rankppm MS/MS Rank ppm (n) 1 C 12H 6N 2O 2F 2 4 -1.4 1 2.2 (7) 2 C 8H 15N 2OP 3 1 -1.3 5 33.5 (4) 3 C 8H 10OF 5P 2 16 4 17.8 (7) 3C 7H 11N 4OFP 230.633.9 (7)This formula finding process is completely automated in the MasterView™ software.Tentative Identification based on ChemSpider Searching and MS/MS InterpretationMasterView™ software allows searching of molecular formulae against ChemSpider to find matching structures. ChemSpider can rank the found structures based on the number of referencesmaking it easy to identify the most likely structure.5The structure is automatically compared against the measured accurate mass MS/MS spectrum using common knowledge on breaking and closing bonds, and re-arrangement. A match factor is calculated to describe the matching of experimental MS/MS pattern with a theoretical fragmentation pattern using theproposed structures. Fragment ions which can be explained by theoretical fragmentation are displayed in blue and fragment ions which cannot be explained are displayed in red in the MS/MS spectrum. The predicted structure of a selected product ion is*******M+H +M+NH 4+M+Na +2040608010012020 ppm10 ppm 5 ppm2 ppmN u m b e r o f m a t c h i n g f o r m u l a eMass accuracyusing the accurate mass molecular ion onlyplus using the isotope pattern (10%)plus using the MS/MS fragment ionshighlighted in the structure display to allow result evaluation. Figures 4 and 5 show examples of identification of Pyraclostrobin and Boscalid with an MS/MS match of 99.4% and 100%, respectively.Figure 4. ChemSpider search results performed in MasterView™ software suggesting Pyraclostrobin being present in a tomato sample, the MS/MS match of 99.4% further confirms the finding of the pesticide Figure 5. ChemSpider search results performed in MasterView™ software suggesting Boscalid being present in a tomato, the MS/MS match of 100.0% further confirms the finding of the pesticideAdditional Results of Non-target ScreeningFigures 6, 7, and 8 show additional results of non-targeted data processing on a series of different food samples. Figure 6. Automatic non-target screening of orange samples, sample-control-comparison reduce the number of chromatographic signals from 1098 to 32 relevant signals, Thiabendazole and Imazalil were identify with high confidenceFigure 7. Automatic non-target screening of trail mix samples, sample-control-comparison reduce the number of chromatographic signals from 2052 to 142 relevant signals, several pesticides were identify with high confidenceControl sampleSampleControl sampleSampleFigure 8. Identification of Niacinamide (vitamin B3) with 99.4% score after sample-control-comparison, formula finding, ChemSpider searching and automatic interpretation of the MS/MS patternFor Research Use Only. Not for use in diagnostic procedures.© 2013 AB SCIEX. The trademarks mentioned herein are the property of AB Sc Publication number: 7830613-01Headquarters353 Hatch Drive Foster City CA 500 Old Connecticut Path SummaryA novel approach of comparative non-target screening to i unexpected and unknown chemicals in food samples was developed and successfully applied to a wide variety of samples. Samples were extracted using a QuEChERS procedure and analyzed with reversed phase LC. High res and accurate mass MS and MS/MS information was collec a single run using information dependent acquisition on the SCIEX TripleTOF ®4600 and 5600 system. Data were proc using MasterView™ software.Sample-control-comparison was performed to differentiate and sample specific signals from true contaminations. Ions interest were automatically searched against mass spectra libraries and processed using automatic formula finding an ChemSpider searching for identification. The new MasterV software offers an easy to use and intuitive workflow to tentatively identify unexpected chemicals in food.References1EU Commission Decision ‘concerning the performance analytical methods and the interpretation of results’ #2002/657/EC2SANCO Document: ‘Method Validation and Quality Co Procedures for Pesticide Residues Analysis in Food an Feed’ #SANCO/12495/20113A. Schreiber and C. Seto: ‘Target and Non-Target Scre for Chemical Residues in Food Samples using the AB TripleTOF ®4600 System and Intuitive Data Processing Tools’ Application Note AB SCIEX (2012) #5680212-4A. Schreiber and C. Borton: ‘Target and Non-Target Screening for Pesticide Residues in Food Samples usi AB SCIEX TripleTOF ®5600 System’ Application Note SCIEX (2010) #0460110-025J. Little et al.: ’Identification of "known unknowns" utilizi accurate mass data and ChemSpider’ J Am Soc Mass Spectrom 23 (2012) 179-185B Sciex Pte. Ltd. or their respective owners. AB SCIEX™ is being used under license.International SalesPath, Framingham, MA 01701 USA For our office locations please call g to identify was of food h resolution collected in on the ABprocessed ntiate matrix . Ions of pectral ng and sterView™ mance ofy Control od and Screening e AB SCIEXessing -01get s using theNote AB utilizing Mass The Complete Series of MasterVie Software Workflow Demos:Video 1:Screen for targeted compounds in your unknownClick /MasterVideo1 to watchVideo 2:Easy set-up of data processing and data review Click /MasterVideo2 to watchVideo 3:Screen for non-targeted compounds in your unk Click /MasterVideo3 to watchse.e call the division View™ known samples atch the video.eview parameters atch the video.r unknown samples atch the video.。
一种实验验证方法英文IntroductionExperimental verification is a crucial process in scientific research, as it provides empirical evidence to support or refute hypotheses. It allows researchers to test their ideas and theories in a controlled environment, providing insights into the underlying mechanisms of natural phenomena. This article presents a method for conducting experimental verification, outlining the necessary steps and considerations for ensuring reliable and valid results.MethodologyStep 1: Formulate a HypothesisThe first step in experimental verification is to formulate a hypothesis. This involves proposing an explanation or a prediction about the relationship between variables. The hypothesis should be specific, testable, and should aim to answer a research question.Step 2: Design the ExperimentDesigning a well-structured experiment is vital to obtaining accurate and meaningful results. The experiment should be carefully planned, ensuring that all relevant variables are identified and controlled. Considerations such as sample size, experimental conditions, and data collection methods should be taken into account during this step.Step 3: Identify VariablesIdentifying and controlling variables is crucial to minimize confounding factors and ensure that the observed effects are due to the manipulated variables. Variables can be classified as independent, dependent, or controlled. Independent variables are manipulated by the researcher, dependent variables are the outcomes or the observed effects, and controlled variables are kept constant to prevent their influence on the results.Step 4: Conduct the ExperimentOnce the experiment has been designed and variables have been identified, it is time to conduct the experiment. Follow the established protocol, collecting relevant data and observations. Take into consideration the ethical guidelines and safety precautions to ensure the integrity of the experiment and the well-being of participants.Step 5: Analyze and Interpret the ResultsAfter data collection, it is important to analyze and interpret the obtained results. Statistical analysis methods can be employed to determine the significance of the observed effects. Consider factors such as margin of error, confidence intervals, and p-values to draw meaningful conclusions.Step 6: Draw ConclusionsBased on the results obtained, draw conclusions regarding the hypothesis. If the data supports the hypothesis, it provides evidence tovalidate the proposed explanation. However, if the data contradicts the hypothesis, it suggests a revision of the initial hypothesis or the formulation of a new one. Ensure that the conclusions are based on sound scientific reasoning and are supported by the empirical evidence obtained from the experiment.Considerations and Potential Challenges- Sample size: Ensure that the sample size is sufficient to achieve statistical power and accurately capture the effects of variables.- Control group: Create a control group to serve as a basis of comparison, allowing the evaluation of the impact of the independent variable.- Replicability: Conduct the experiment multiple times to ensure the reliability of the results. Replicability adds strength to the validity of the findings.- Ethical considerations: Adhere to ethical guidelines and obtain necessary consent from participants to maintain the ethical integrity of the experiment.- External validity: Consider the generalizability of the results to the broader population or other settings. It is important to acknowledge any limitations or potential biases that might affect the external validity. ConclusionExperimental verification is a foundational aspect of scientific research. By following the outlined methodology and taking into account theconsiderations and potential challenges, researchers can conduct experiments that generate reliable and valid results. Through rigorous experimentation, scientists are able to advance knowledge, inspire further research, and make important contributions to their respective fields.。
新视野⼤学英语4:Unit1TextB(课⽂+译⽂) 新视野4:Unit1 Text B的科⽬题⽬是聪明的⼈为何会做蠢事。
下⾯是yjbys⼩编为⼤家带来的新视野4:Unit1 Text B (课⽂+译⽂),欢迎阅读。
Why do smart people do dumb things? 聪明的⼈为何会做蠢事? 1.Orthodox views prize intelligence and intellectual rigor highly in the modern realm of universities and tech industry jobs. One of the underlying assumptions of this value system is that smart people,by virtue of what they’ve learned,will formulate better decisions.Often this is true.Yet psychologists who study human decision-making processes have uncovered cognitive biases common to all people,regardless of intelligence,that can lead to poor decisions in experts and laymen alike. 1.传统观念将智⼒和思维的缜密性看作现在⼤学领悟和科技产业⼯作的重要素质。
这⼀价值体系所隐含的前提是,聪明⼈借助⾃⼰的学识会做出更⾼明的决定。
在⼤多数情况下,的确如此。
但是,研究⼈类决策过程的⼼理学家们却发现了每个⼈⾝上都常见的“认知偏差”。
不管智⼒⽔平如何,这些认知偏差都会引导们作出错误的决定,不论他们是专家还是门外汉。
2.Thankfully these biases can be avoided.Understanding how and in what situations they occur can give you an awareness of your own limitations and allow you to factor them into your decision-making. 2.好在这些偏差是可以避免的。