• Experiments in analytical chemistry, including analysis of solution samples, titrimetric and electroanalytical methods. (sfu.ca)
  • You will carry out experiments in analytical and physical chemistry, and an integrated chemistry project as an introduction to research. (york.ac.uk)
  • What benefits did you anticipate by using OES over other analytical techniques for your intended analysis? (spectroscopyonline.com)
  • Here we speak about diagnostic rather than analytical techniques, because we did not (and could not) use OES for elemental analysis. (spectroscopyonline.com)
  • familiarity with the, Experience in analytical chemistry within a, Introduction to reviewing analytical documentation for analysis performed by other analysts…, High School Diploma with three (3) years' experience in a similar position in the. (thelittlebigshow.com)
  • The laboratory analytical methods available are capable of defining the qualitative existence of a variety of pharmaceuticals, drugs of abuse, and occupational/environmental toxicants. (cdc.gov)
  • In addition, the analytical techniques currently in use are capable of providing 'segmental analysis' of hair, which in turn can provide a historical picture of various qualitative (not quantitative) exposures over time. (cdc.gov)
  • e.g digestion of samples in an analytical laboratory using HNO 3 , catalyst in chemical reactions, acidic hydrolysis, pH adjustments, manufacturing of fertilizers, synthesis of nylon, etc). (itwreagents.com)
  • More importantly, this approach shows no loss of metabolic information in the commonly employed biofluids with highly abundant macromolecules, and exhibits the required reproducibility for metabolomics and other analytical studies, greatly improving the quantitative and qualitative NMR analytical assets while dramatically reducing the instrument time and resource required. (github.io)
  • Sugar composition analysis is another frequently employed analytical methods for quality control of polysaccharides [ 14 ]. (biomedcentral.com)
  • A series of experiments were conducted to quantify and characterize the optical and physical properties of combustion-generated aerosols during both flaming and smoldering combustion of three materials common to underground mines - Pittsburgh Seam coal, Styrene Butadiene Rubber (a common mine conveyor belt material), and Douglas-fir wood - using a combination of analytical and gravimetric measurements. (cdc.gov)
  • It involves tedious procedures such as acid hydrolysis and derivatization, followed by chromatographic qualitative and quantitative determination of sugar derivatives. (biomedcentral.com)
  • Do literature search then perform electrophoresis and kinetics experiments independently or as a team in a safe manner and report and results using scientific writing. (uaeu.ac.ae)
  • Conduct chemical and physical laboratory tests to assist scientists in making qualitative and quantitative analyses of solids, liquids, and gaseous materials for research and development of new products or processes, quality control, maintenance of environmental standards, and other work involving experimental, theoretical, or practical application of chemistry and related sciences. (estrellamountain.edu)
  • Cannabis extracts contain in addition to Δ-9 and Δ 8 -THC many other cannabinoids and chemical compounds, such as esters and alkaloids, the effects of which will have to be evaluated separately and in combination. (unodc.org)
  • Interested in developing chemical compounds? (kent.ac.uk)
  • He/she prepares test solutions and other needed compounds for lab personnel to conduct their experiments. (employeepedia.com)
  • In addition, they also get to undertake other roles such as writing technical papers and reports, confer with scientists and other project staff to conduct analyses of a research project, develop and improve lab processes so as to improve efficiency and undertaking various studies to determine the various effects of other compounds. (employeepedia.com)
  • It is a powerful tool that facilitates structure determination of pure compounds (and in some cases even of mixtures of compounds), offers insight into the characteristics of materials, and allows reaction monitoring to provide understanding of chemical reaction mechanisms. (ukri.org)
  • To educate and train students to have a sound knowledge of chemical compounds and processes. (edu.ng)
  • related chemical compounds, physical agents (such as radiation) and biological factors (such as viruses). (who.int)
  • Chemical analogues and compounds with biological or physical characteristics similar to those of suspected carcinogens may also be considered, even in the absence of data on a possible carcinogenic effect in humans or experimental animals. (who.int)
  • Several studies have shown that the Subsequent chemical analysis confirmed psychostimulant effects induced by chew- that the fresh leaves contain a number of ing khat leaves include a moderate degree compounds, including phenylalkylamine of euphoria and mild excitement resulting compounds (alkaloids) such as nor- in promotion of social interaction and lo- pseudoephedrine (cathine) and alpha ami- quacity [8,11,12]. (who.int)
  • Study the chemical composition or physical principles of living cells and organisms, their electrical and mechanical energy, and related phenomena. (estrellamountain.edu)
  • Consequently, the reports of toxicologic and pharmacologic effects of crude extracts or synthetic derivatives of cannabis published before 1968 lack precision and uniformity and preclude any quantitative correlation between physiological effects and chemical composition. (unodc.org)
  • LIBS will help derive the chemical composition and infer mineralogical composition to further our understanding of the lunar surface. (mosshimonaco.xyz)
  • Induce changes in composition of substances by introducing heat, light, energy, or chemical catalysts for quantitative or qualitative analysis. (monster.com)
  • The texts concern the qualitative and quantitative composition of medicines, the tests to be carried out on medicines, on the raw materials used in the production of medicines and on the intermediates of synthesis. (lu.se)
  • Subsequent more plicated by incomplete knowledge about the chemical systematic studies attributed the relaxation enhancement composition and supramolecular structure of most tissues. (lu.se)
  • G. S. Newth was the author of a number of popular books in chemistry, most notably Chemical Lecture Experiments [Reviewed in Nature 47, 97-98 (1 December 1892)]and Inorganic Chemistry. (wikipedia.org)
  • Chemical Lecture Experiments (one of 5 books by Newth published by Longman, Green & Company of London, England) first appeared in 1892 and is a collection of chemistry lecture experiments all of which the author had tried for himself. (wikipedia.org)
  • Newth also wrote A Manual of Chemical Analysis - Qualitative and Quantitative published in 1898 and Elementary Practical Chemistry first published about 1896 (earliest UK copy seen is 1904) which was for school chemistry classes. (wikipedia.org)
  • first published in 1892) G. S. Newth: "An apparatus for showing experiments with ozone", Journal of the Chemical Society, Transactions 69, 1298-1299, Royal Society of Chemistry, 1896. (wikipedia.org)
  • Kitchen chemistry experiments can supplement the in person experience in non-major and introductory chemistry sequences . (acs.org)
  • Enter the fascinating world of Chemistry at Kent to gain the knowledge and practical skills to help tackle global challenges such as developing renewable energy and biomaterials and combating chemical warfare. (kent.ac.uk)
  • The versatility of NMR spectrometers and associated types of NMR experiments has made them essential tools that are ubiquitous in chemistry departments. (ukri.org)
  • The instrument will provide very high sensitivity and a low limit of detection for multinuclear liquid samples, especially for detecting heteroatoms, and will underpin a broad range of research areas including Catalysis, Chemical Reaction Dynamics and Mechanisms, Synthetic Organic Chemistry, Synthetic Supramolecular Chemistry, Synthetic Coordination Chemistry, Synthetic Biology, Geochemistry, Medicinal Imaging and Chemical Biology and Biological Chemistry. (ukri.org)
  • This study aims to determine how chemistry teacher candidates use volumetric analysis problems and reveal the errors made. (mierjs.in)
  • Volumetric analysis and chemistry students' performance: Combined influence of study habit, physiological and psychological factors. (mierjs.in)
  • A comparison of chemistry instruction enriched with experiments and traditional problem solving activities of chemistry lesson achievement. (mierjs.in)
  • The effect of different problem-solving strategies on university students' problem-solving achievements of quantitative problems in chemistry. (mierjs.in)
  • The Division of Surface Chemistry of the Swedish Chemical Society. (lu.se)
  • Reaxys enables you to search by structure, substructure, reaction, text, and property data.Being based on the CrossFire Beilstein, CrossFire Gmelin and Patent Chemistry databases Reaxys has a long history beginning with chemical data from 1771. (lu.se)
  • SciFinder-N provides access to the world's most comprehensive and authoritative source of references, substances and reactions in chemistry, chemical engineering, food, biomedicine and related sciences. (lu.se)
  • The course consists of the following: -the environmental work at Chemistry Center and Lund University -hazards concerning chemicals -protection gear -safety regulations -laws and regulations for environmental safety -hazard evaluations -accidents. (lu.se)
  • The aim of this course is to provide students with a knowledge of the chemicals of life (carbohydrates, lipids, amino acids, proteins, nucleic acids etc.): their structures, characteristics, chemical reactions and functions in the body and an ability for their qualitative and quantitative analysis. (yeditepe.edu.tr)
  • This two-part column explains how lipids analysis has evolved and the variety of techniques and approaches currently used in lipidomics, including their advantages and disadvantages, such as sample preparation, separations and, of course, mass spectrometry. (chromatographyonline.com)
  • For years, biomedical research focused on analysing only a handful of lipids. (chromatographyonline.com)
  • Because lipids are present in all living organisms, other areas of applications such as plant, microbial and nutritional research could also benefit from improvements in lipid analysis and a better understanding of lipid metabolism. (chromatographyonline.com)
  • Some classes of lipids are more amenable to analysis by one type of ionization versus another, and the optimal conditions for each vary, such as gas flow, temperature, and voltage. (usda.gov)
  • Whenever possible, programs should do their best to reasonably accommodate student needs by modifying laboratory experiments or environments. (acs.org)
  • Laboratory experiments designed to reflect the topics taught in CHM 101 and CHM 102 such as qualitative and quantitative chemical analysis, acid-base titrations. (edu.ng)
  • Operate or tend equipment to control chemical changes or reactions in the processing of industrial or consumer products. (azwestern.edu)
  • May conduct research to further understanding of the complex chemical combinations and reactions involved in metabolism, reproduction, growth, and heredity. (estrellamountain.edu)
  • Curious about the structure of chemicals and the reactions they have with one another? (kent.ac.uk)
  • Study of chemical reactions on surfaces under controlled environments. (unizar.es)
  • Students' dilemmas in reaction Stoichiometry problem- solving: deducing the limiting reagent in chemical reactions. (mierjs.in)
  • It contains the PatentPak modul, which can quickly localize chemical information within patents, and chemical reactions are documented in greater details. (lu.se)
  • Analyze results of experiments and procedures using manual or computer techniques and, if necessary, develop special computer programs to facilitate analysis. (insidehighered.com)
  • Ability to design and conduct experiments, gather data, analyze and interpret results for investigating engineering problems. (yeditepe.edu.tr)
  • Experiments are also described in which two systems for separation of molecules (liquid chromatographs) are used in combination to analyze complex samples. (usda.gov)
  • The introduction of complementary DNA (cDNA) microarray technology in 1995 has helped to facilitate the identification and classification of DNA sequence information and the assignment of functions to these new genes by allowing investigators to analyze expression of thousands of genes simultaneously in a single experiment. (medscape.com)
  • For more than 15 years, the set experimental procedure for NMR analysis of biofluids such as these has consisted of a standard 1H-NMR experiment (e.g. 1D-NOESY), a pseudo 2D J-Res experiment for supporting small molecules assignment, and a spin-echo experiment (e.g. (github.io)
  • However, there is interest in the possibility of Peptide reactivity exploiting these same experimental approaches to distinguish between different forms of chemical aller- gens - as individual materials are primarily associated with one or the other form of sensitization in humans. (cdc.gov)
  • Quantitative extrapolation from experimental data to the human situation is not undertaken. (who.int)
  • The course covers the basics, principles and limitations for the most common methods for multivariate statistics (analysis of variance, principal component analysis and partial least squares regression), experimental design (super-saturated and factorial designs) and method validation with a focus on practical use. (lu.se)
  • You'll begin with themes of structure and bonding, and chemical change and reactivity, with practical courses complementing the lectures, and then take interdisciplinary modules that introduce key chemical principles in the areas of spectroscopic analysis, bonding and chemical change, and chemical reactivity and mechanisms. (york.ac.uk)
  • The main objectives of the project included the compilation, evaluation and generation of high quality in vitro and in vivo data on a set of reference chemicals for comparative analyses, and the identification of factors that influence the correlation between in vitro (concentration) and in vivo (dose) toxicity, particularly taking into consideration biokinetics, metabolism and organ toxicity (liver, central nervous system, kidney). (enhesa.com)
  • It is a simplicity of OES plus our previous experience in classification of materials by various chemometric techniques, like using correlation or principal component analyses. (spectroscopyonline.com)
  • Confer with scientists or engineers to conduct analyses of research projects, interpret test results, or develop nonstandard tests. (monster.com)
  • Prepare specimens or record data to assist scientists in biology or related life science experiments. (oregonstate.edu)
  • Chemists, geochemists, materials and life scientists require rapid and high-throughput access to methods that extract both qualitative and quantitative information from increasingly complex samples matrices. (ukri.org)
  • Qualitative assays Determine if specific substance is there or not, by color or some other quality Quantitative assays Determine the concentration of a substance Specifity and sensivity Sensitivity of an assay is a measure of how little of the analyte the method can detect Specificity of an assay relates to how good the assay is in Summarize the results and observations from an experiment into a short laboratory report. (iyama.org)
  • The amount of hair needed for analysis may be dependent on the specific analyte sought as well as the temporal relationship between exposure and hair harvest. (cdc.gov)
  • As a researcher, you MUST understand how qualitative data analysis differs from quantitative data analysis. (iyama.org)
  • Second, qualitative and quantitative characterization of the extracted HPMs was performed using high performance gel permeation chromatography (HPGPC). (biomedcentral.com)
  • The Lander and the Rover have scientific payloads to carry out experiments on the lunar surface. (mosshimonaco.xyz)
  • Gravimetric analysis. (edu.ng)
  • Laser photometers were utilized in the experiments for continuous measurement of aerosol mass concentrations and for comparison to measurements made using gravimetric filter samples. (cdc.gov)
  • The aim of the course is to provide students with an opportunity (after a successful review of the chemical literature) to apply their biochemical knowledge and skills to an area of research without the restrictions of a planned practical. (uaeu.ac.ae)
  • Prepare data summaries, reports, or analyses that include results, charts, or graphs to document research findings and results. (oregonstate.edu)
  • May specialize in a field of computer science, such as the design and function of computers or operations and research analysis. (alabamanow.com)
  • The first thing that comes in mind while writing a research paper is whether it is qualitative or quantitative in nature. (iyama.org)
  • Choosing between qualitative vs. quantitative research can be challenging, especially if you do not know their differences. (iyama.org)
  • Although there are many books about traditional medicines research, they mostly focus on either chemical or pharmacological study results of certain plants. (chipsbooks.com)
  • Greater investment inflows and a surge of activity, especially in the field of drug and biomarker discovery, is fuelling the growth of global lipid analysis - lipidomics - making it a standard research tool in academic, pharmaceutical and biotechnology sectors. (chromatographyonline.com)
  • In 1969, the International Agency for Research on Cancer (IARC) initiated a programme to evaluate the carcinogenic risk of chemicals to humans and to produce monographs on individual chemicals. (who.int)
  • Apply Theoretical Principles To Perform And Interpret Experiments In Biochemistry. (uaeu.ac.ae)
  • Certainly these facts limit the clinician's ability to interpret and utilize hair-derived values beyond the potential qualitative information that might come from hair testing of any individual. (cdc.gov)
  • ACuteTox set the very ambitious overall objective of developing an in vitro test strategy sufficiently robust and powerful to completely replace in vivo testing of acute toxicity of chemicals. (enhesa.com)
  • In the latter case, clearly specified quantitative benchmarks, such as median lethal doses (LD50s) for acute toxicity and no- observed-adverse-effect levels (NOAELs), or equivalent point of departure such as benchmark dose lower confidence limit (BMDL), for STOT-RE, are used. (cdc.gov)
  • Acids and bases are important groups within the classification of chemical substances, since they are widely used in any type of laboratory or industrial process due to their multiple applications. (itwreagents.com)
  • Student difficulties with volumetric analysis. (mierjs.in)
  • Apply fundamental theories of physical, chemical, and life sciences to construct models to demonstrate an understanding of fundamental biochemical principles, such as the structure/function of biomolecules, metabolic pathways, and the regulation of biological/biochemical processes. (estrellamountain.edu)
  • From the extrapolated results of those narrowly focused analyses, we sought to understand more than we could reasonably expect to know: the multifaceted mechanisms of action and the effects of drugs, the causes of complex diseases and the intricate biological alterations associated with those diseases. (chromatographyonline.com)
  • According to the both chemical and biological results, fengdou by boiling with water for 4 h is the most recommended specification and edible method for DC. (biomedcentral.com)
  • However, a systems biological analysis of the lipidome, by incorporating pathway information remains challenging, leaving lipidomics behind compared to other omics disciplines. (mdpi.com)
  • At our microscopy platform in Lund, you meet personnel with expertise and long experience working with biological material and microscopy, imaging, and analysis. (lu.se)
  • These quantitative experiments do replicate to a great extent the qualitative results obtained with cannabis extracts. (unodc.org)
  • Abstract -This study aims to determine the impact of learning with the Project-Based Learning (PjBL) integrated with Instagram social media in increasing learning motivation and students' creative thinking abilities in chemical material reaction rate. (ijiet.org)
  • Transcriptome analyses revealed that genes involved in defense pathways are generally downregulated in progeny of nematode-infected plants under uninfected conditions but show a stronger induction upon nematode infection. (bvsalud.org)
  • Chandra's Surface Thermophysical Experiment (ChaSTE) will carry out the measurements of thermal properties of the lunar surface near the polar region. (mosshimonaco.xyz)
  • A key requirement for these measurements (particularly applications requiring analysis of trace quantities) is a push to lower the limit of detection by increasing instrument sensitivity. (ukri.org)
  • Quantitative local electrical resistance measurements. (unizar.es)
  • Qualitative measurements of local charge distribution. (unizar.es)
  • The data produced from a microarray experiment typically constitute a long list of measurements of spot intensities and intensity ratios, generated either by a pair-wise comparison of 2 samples or by a comparison of several samples with a common control. (medscape.com)
  • Gene ontology analysis was performed on 844 differentially expressed genes and confirmed the shift in metabolic fuel utilization, inhibition of RNA transcription and cell cycle regulation as found in seasonal hibernators. (bvsalud.org)
  • Removal of the melanin from hair digests prior to hair analysis may reduce the effect of melanin on the total chemical concentration by excluding the drug bound to the pigment. (cdc.gov)
  • As described in the applications section, spectrophotometry can be used in both qualitative and quantitative analysis of DNA, RNA, and proteins. (iyama.org)
  • This latter experiment is the only commonly applied method for mitigating the strongly confounding signals from proteins and other large biochemical structures, to reveal the underlying signals from small molecules. (github.io)
  • The team says while they still cannot fully identify specific health effects, the findings are worrisome because infants are vulnerable to chemical toxins and chemical exposures. (blogsocialnews.com)
  • In addition, hair analysis may help to derive an essential time frame which may indicate, based on the average rate of hair growth, the time of inception for various exposures. (cdc.gov)
  • The Monographs programme has since been expanded to include consideration of exposures to complex mixtures of chemicals (which occur, for example, in some occupations and as a result of human habits) and of exposures to other agents, such as radiation and viruses. (who.int)
  • This book covers the systematic study and analysis of herbal medicines in general - including chemical isolation and identification, bioassay and mechanism study, pharmacological experiment, and quality control of the raw plant material and end products. (chipsbooks.com)
  • As we move into a new era of lipid analysis, the potential to accurately and rapidly measure hundreds of individual molecular species provides the opportunity to use more complex lipid profiles for drug discovery and disease diagnostics. (chromatographyonline.com)
  • Liquid chromatography (LC) coupled to mass spectrometry (MS) has become the method of choice for analysis of complex lipid samples. (usda.gov)
  • Thus, there is no single LC-MS technique that is ideal for analysis of all lipid classes. (usda.gov)
  • The questions should be answered on a separate (new) page of your lab … It includes a qualitative analysis of phosphates and nitrogen in fertilizer products. (iyama.org)
  • It produces a spectrum which replaces and improves on weaknesses of, for example, CPMG, providing complete suppression of the macromolecular signals and enhanced spectral resolution, while retaining the quantitative nature of the original 1H-NMR data. (github.io)
  • With Supplement 6 (IARC, 1987a), the title of the series was modified from IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans to IARC Monographs on the Evaluation of Carcinogenic Risks to Humans , in order to reflect the widened scope of the programme. (who.int)
  • Detailed, quantitative evaluations of epidemiological data may be made in the Monographs , but without extrapolation beyond the range of the data available. (who.int)
  • Ltd. Chemical mixtures absorb, transmits and reflect light in a particular range of wavelength. (iyama.org)
  • Two types of ionization sources have emerged as the most commonly used to couple LC to MS: atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI). (usda.gov)
  • Teach courses pertaining to the chemical and physical properties and compositional changes of substances. (azwestern.edu)
  • The successful candidate will be responsible for performing chemical and physical testing of new products. (thelittlebigshow.com)
  • Biochemistry and Biophysics involves life science, quantitative work, and physical science training. (oregonstate.edu)
  • The first experiment uses a batch column operated at total reflux to introduce students to multistage distillation including efficiency and energy balances at total reflux. (aiche.org)
  • This project engages students in process dynamics and challenges them to compare analysis using the Rayleigh equation methodology to actual data, for a batch column operated at a constant external reflux ratio. (aiche.org)
  • Certificates of analysis should be included for the biobatch of the proposed product and the relevant batch of the comparator product, analysed at a time near the time of the BE study. (who.int)
  • However, completing the Tier 2 process could be beneficial even in this situation, as the user may gather more detailed chemical information and possibly move the chemical into a different band. (cdc.gov)
  • Apply and effectively communicate scientific reasoning and data analysis in both written and oral forums. (estrellamountain.edu)
  • Calculation, data analysis and presentation. (edu.ng)
  • Data analysis used qualitative and quantitative descriptive tests with independent sample t-tests and N-Gain. (ijiet.org)
  • Because of the complexity of the data sets generated by microarray experiments, the use of data-analysis software is essential. (medscape.com)
  • And, there are only a few studies of chemical engineering systems. (aiche.org)
  • In vitro methodology have focused primarily on skin sensitizing chemicals. (cdc.gov)
  • Small-scale fermentations and sensory and chemical analysis can also help assess for smoke-exposure characteristics. (mossadams.com)
  • Earlier, unpublished versions of the NIOSH Occupational Exposure Banding process included band-specific ranges that approximate the GHS hazard categories, but has refined these cut points based on exposure response analyses, comparisons of OEBs to current OELs, and technical expertise. (cdc.gov)
  • To ensure the cut points reflect a range of potencies, the fraction of chemicals covered by each occupational exposure band was determined and compared to the potency distribution of a diverse set of chemicals for some endpoints. (cdc.gov)
  • The Tier 2 process for occupational exposure banding also assesses the sufficiency of toxicity data to ensure that adequate information is available to reliably band a chemical. (cdc.gov)
  • Primary microplastics are small pieces of plastics manufactured by humans for a certain purpose, mainly from synthetic textile fiber shedding, synthetic rubber wear, road marking materials, ship coatings, daily chemical plastic beads and so on. (blogsocialnews.com)
  • The AJCSD includes chemical regulatory information, GHS classification results, risk and hazard information, etc. (enhesa.com)
  • Laboratory includes both quantitative and qualitative experiments. (laspositascollege.edu)
  • One of the most important shortcomings for hair analysis, as it currently exists, is the fact that reference ranges may often be unreliable. (cdc.gov)
  • The data demonstrate how the shortcomings of any single instrument are overcome by employing mass spectrometers that acquire complementary data from the same analytes, and demonstrate that such an arrangement provides a greater degree of confidence in both qualitative and quantitative results. (usda.gov)
  • Lastly, an analysis of upstream regulators identified RE1-Silencing Transcription factor (REST) as a potential mediator of this DNA methylation signature. (bvsalud.org)
  • Recently, Alem and Shibre considered the differences in the effect of khat and khat as a substance of abuse and noted that amphetamine are quantitative rather than chewing had the potential to complicate qualitative [20,21]. (who.int)
  • Laboratory emphasizes quantitative techniques, including instrumentation, and qualitative analysis. (laspositascollege.edu)
  • In our laboratories, you can use both standard microscope techniques, like scanning electron microscopy (SEM), transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM), as well as infra-red based analysis techniques and micro-computed tomography (micro-CT). (lu.se)
  • With an associate`s degree, students may qualify as a chemical technician. (estrellamountain.edu)
  • Core value to provide access to a high-quality chemical education to all students. (acs.org)
  • Sampling was taken using a random sampling technique involving two XI classes at State High School 1 Singosari, namely 29 students for the class of control and 33 students for the class of experiment. (ijiet.org)
  • Students have to work in combined teams of 8-10 people (not at all conducive to learning), or run experiments during times when safety and lab monitoring because serious issues. (aiche.org)