Posted: February 19th, 2022

Lab 1 – The Scientific Method

Revised: August 7, 2019 1

ENVR 1401 – BACKGROUND

Lab 1 – Scientific Method

Studying Aims:

1. Define the steps to the scientific methodology.

2. Establish testable observations.

three. Distinguish between dependent and unbiased variables.

four. Gather, manage, and current scientific knowledge.

Overview

This exercise explores the idea and utility of the scientific methodology. To differentiate true cause- impact

relationships from associations or perceptions, phenomena should be investigated utilizing designed experiments

and cautious observations that may be repeated by others.

The scientific methodology is often mentioned as a standardized, linear course of that features the next steps and entails particular abilities:

1. Make observations or collect knowledge ➔ typically results in a Question Assignment

2. Formulate a speculation which results in an related prediction

three. Design an applicable take a look at/experiment to evaluate the speculation/prediction

four. Conduct take a look at/experiment, file and analyze the outcomes (together with mathematical and statistical analysis)

5. Interpret the outcomes and draw conclusions ➔ settle for, revise, or reject the speculation

6. Reporting the outcomes (e.g., laboratory report, formal memorandum, peer reviewed article)

Revised: August 7, 2019 2

However, as proven within the circulate chart, the method is just not linear. It’s cyclical as a result of good science stimulates

additional thought and mandates that concepts be challenged and additional examined to reveal that the outcomes will be repeated (iterative course of). A scientific speculation is an knowledgeable, testable, and predictive rationalization

of a pure phenomenon, course of or occasion. If, upon testing, the scientific speculation fails the take a look at, it should be

rejected or could also be modified and topic to additional testing. Fashions are mathematical or conceptual

hypotheses that present helpful views, although typically restricted by oversimplification of the method they characterize.

If, nonetheless, a scientific speculation continues to move repeated assessments and the predictions have been verified,

then it’s thought-about a corroborated speculation. A extremely corroborated speculation which has been repeatedly examined and is supported by vital dependable proof is taken into account a scientific truth or pure

legislation, such because the existence of gravity as a property of all matter.

A unifying and constant rationalization of elementary pure processes or phenomena that’s constructed of

corroborated hypotheses and scientific info is a scientific idea. Scientific theories, corresponding to quantum

mechanics, thermodynamics, plate tectonics, evolution, or relativity, are probably the most dependable and complete type of human data. And, as we achieve extra data via the appliance of the

scientific methodology, our understanding of the universe through which we stay and our theories on the way it capabilities

and evolves should proceed to be refined.

Additional worth of the scientific methodology is derived from honing and making use of crucial abilities to develop

scientific data:

◼ making, recording, and reporting unbiased measurements

◼ classifying knowledge

◼ translating and analyzing data

◼ making use of deductive and inductive logic

◼ essential, interpretive, and artistic pondering

◼ figuring out and controlling variables

The scientific methodology established an strategy to an issue and enforces scientific thought that makes an attempt to

remove bias within the ensuing knowledge and conclusions. Science depends upon empirical proof which is

observable and measurable by multiple researcher. However as people, we are inclined to view the world and

options to issues inside our private framework. For instance, if a city alongside the river is repeatedly

flooded, then the structural engineer believes the issue can be solved by constructing a dam and the politician might consider than any resolution is just too costly or unpopular and could be detrimental to being re-elected. In

distinction, the pure useful resource supervisor might want limiting city improvement and re- establishing native

habitat. The propensity of people to understand the world from their perspective is sweet motive to have a wholesome dose of skepticism — to consistently Question Assignment your beliefs, observations, and conclusions.

Scientific methodology has an extended historical past that dates again over 1,000 years, with many cultures and

people contributing to its improvement. Historic Egyptian papyri describe strategies of medical prognosis and empiricism. Empirical proof present in nature permits us to explain and clarify pure processes and

pure legal guidelines. The first experimental scientific methodology was developed by Muslim scientists. Alhazen (Ibn al-

Haytham, 965-1039) is credited with introducing experimentation and quantification in his work on optics, amongst his vital contributions to astronomy, engineering, physics, medication, and science typically. In

Europe the Renaissance resulted in renewed curiosity within the concepts and science developed through the Greek and

Roman empires.

The logic and philosophical approaches of Aristotle and Socrates had been improved upon by Francis Bacon in

the early 1600s. Descartes formalized the guiding rules for the scientific methodology, strengthening the hyperlink between science and arithmetic. Galileo additionally confirmed the significance of testing or experimenting to look

for the alternative of a consequence to probably disprove an concept. Within the late 1800s, Peirce outlined goal

strategies utilizing deduction and induction as complementary approaches, in addition to outlining the fundamental scheme for speculation and testing that we at the moment use.

Revised: August 7, 2019 three

Deduction and induction are varieties of argument or logical approaches. Deduction, in easiest phrases, is the

logical means of arriving at a conclusion primarily based on premises (e.g., info, statements, legal guidelines) which have been verified. Induction, in easiest phrases, is the logical means of arriving at a conclusion primarily based on premises

which can be assumed to be true; subsequently, some conclusions of inductive thought processes could also be false.

Deduction is usually described as shifting from the extra normal to the extra particular. For instance, the Legislation of Gravity expresses the power that draws objects to one another. In frequent phrases, it explains why

objects fall towards Earth or, within the setting, why water flows downhill. Primarily based on the Legislation of Gravity we

would deduce that weathered soil supplies would additionally transfer down slope. Induction is usually described

as shifting from particular observations or particulars to a normal assertion. For instance, we start by making observations or measurements, detect patterns or regularities, and develop a normal conclusion. In

utility, for those who contact a range ten occasions and every time you contact the range, you burn your hand. You

would possibly conclude that the range is at all times sizzling. However this conclusion might or will not be true.

The scientific methodology can by no means “completely show” or present “fact” to grasp. To paraphrase

Einstein, “No quantity of experimentation can ever show me proper; a single experiment can show me

incorrect.” For that reason, and to beat the human bias for seeing what we wish to see, we have to contemplate trigger-impact relationship exists (speculation) AND contemplate perceived trigger-impact

relationship doesn’t exist (null speculation).

Step 1 – Make observations or collect knowledge

Consciousness of the environment might result in posing a Question Assignment. Such consciousness might end result from making

observations round us, gathering preliminary knowledge that mirror environmental situations, or by researching

and studying printed work of others. This strategy typically results in the popularity of a broad drawback that warrants additional investigation. For instance, “Is our water reservoir clear and secure?” Exploring this Question Assignment

by additional studying and analysis might permit refinement of the Question Assignment. For instance, “Is chemical “A” in our

water provide reservoir?” The Question Assignment will present a foundation for additional investigation.

Step 2 – Formulate a speculation which results in an related prediction

To formulate a speculation, you will need to focus the posed Question Assignment and to outline a particular parameter to

be investigated with an anticipated end result. The prediction could also be 1) there can be a particular final result within the

experiment, 2) there can be a statistical distinction between the examined topic and a management, or three) there’ll

be no distinction between the examined topic and the management. Formulation of the speculation is essential as a result of it is going to Help to outline and description the experiment by way of the precise parameters (unbiased and

dependent variables) which can be being assessed.

The speculation is a press release of the almost definitely final result of the experiment. Extra appropriately, the

speculation (designated by HA) must be considered as a prediction that may be examined, is just not ambiguous, and is dichotomous (a “sure” or “no” assertion).

HA: Lower than 5 mg/l of chemical “A” within the reservoir water can be deadly to bluegill minnows.

However keep in mind that the prediction might be faulty. Due to this fact, a null speculation (designated by H0) should even be developed:

H0: Lower than 5 mg/l of chemical “A” within the reservoir water is not going to be deadly to bluegill minnows.

Vary of tolerance — In environmental science, we frequently examine the connection between organisms

and the abiotic (non-dwelling or bodily) traits of the setting, corresponding to temperature, moisture,

nutrient availability, and nutrient toxicity. Most organisms thrive beneath optimum environmental situations. There’s a small proportion of every species that may survive beneath much less-than-superb situations regardless of being

physiologically confused. Such organisms will extra readily adapt to altering environmental situations and

thus make sure the survival of the species. Sometimes called the Legislation of Tolerance, this relationship between inhabitants dimension and environmental situation is mirrored within the following determine. This curve may mirror

the connection between, for instance, numbers of predators and the prey inhabitants.

Revised: August 7, 2019 four

Idealized Vary of Tolerance Curve

Step three – Design an applicable take a look at/experiment to evaluate the speculation/prediction

A nicely-designed experiment must have an unbiased variable and a dependent variable. The

unbiased variable is what the scientist manipulates within the experiment. The dependent variable

responds to the manipulation of the unbiased variable. Due to this fact, the dependent variable offers the information for the experiment. Mentioned one other manner, the unbiased variable causes a response that’s measured as

the dependent variable…. or…the unbiased variable could also be thought-about as an motion that ends in a

response (dependent variable). Think about, for instance, a hearth alarm in a constructing. It isn’t till the alarm

rings that folks will shortly evacuate the constructing. Due to this fact, it’s the ringing of the alarm that is the unbiased variable that causes the dependent response of individuals shortly evacuating the constructing.

Variables which can be held fixed are known as managed variables. For instance, if we needed to check the

results of various the extent of dissolved oxygen on the survival of fish, then we’d keep different

environmental elements (corresponding to temperature, mild, availability of meals) fixed to make sure that they weren’t affecting whether or not the fish survived.

A nicely-designed experiment ought to distinguish between the remedy (the experimental situation) and

the management (reference for comparability). All variables are held fixed for the management. For the remedy,

solely the unbiased variable is modified to find out the ensuing final result (dependent variable). The management is a supply of reference and, since no variables are manipulated for the management, then no response or

change must be famous. If the management stays fixed, then modifications that end result from the manipulation of

the unbiased variable for the remedy are attributed to the experimental issue.

If modifications are famous within the management, then such modifications are attributed to a number of confounding variables. The issue with confounding variables is that they aren’t readily recognized earlier than or throughout

the examine and sometimes resulting in misinterpreted or incorrect outcomes.

Step four – Conduct take a look at/experiment, file and analyze the outcomes

The knowledge could also be qualitative (a verbal description of noticed outcomes of the experiment) or quantitative (involving the gathering of numerical values that may be mathematically assessed or utilized

to a statistical mannequin). Commentary should be thorough and neutral. However, be cautious to current your knowledge

in a factual method. Your interpretations, opinions and conclusions are NOT a part of presenting and analyzing the outcomes – they correctly belong to Step 5.

Devices used to gather knowledge must be correctly calibrated. Testing gear and strategies must be

constant all through the investigation. A number of assessments must be carried out on every take a look at parameter, and the

existence of outliers (uncommon values) must be famous. When outliers are noticed, the testing strategies

and gear must be checked rigorously for malfunctions and recording errors. Lastly, all observations

Revised: August 7, 2019 5

should be famous in everlasting written documentation in order that it may be evaluated later and by others.

Sources of Error – To evaluate validity of scientific work, sources of error must be recognized and evaluated. Widespread sources of error might end result from measurements, testing procedures and human error.

Precision is a measure of the scatter, dispersion, or potential to duplicate the measurements. Low-precision (excessive-scatter) measurements are known as noisy knowledge. Smaller common distinction between repeat

(replicate) measurements means increased precision. For instance, if a sheet of paper is measured a number of

occasions with a ruler, we would get measurements corresponding to 10.9, 11.zero, 10.9, and 11.1 inches. If a micrometer is

used as an alternative, we would get measurements corresponding to 10.97, 10.96, 10.98, and 10.97 inches. These estimates present random variation whatever the measuring machine, however the micrometer provides a extra exact

measurement than does the ruler. If the ruler or micrometer is poorly made, it might yield measurements

which can be persistently offset, or systematically biased, from the true lengths. Accuracy is the extent to which the measurements are a dependable estimate of the ‘true’ worth. Each random errors and systematic

biases scale back accuracy. To scale back errors of measurement, many measurements could also be obtained after which

averaged to aim to reduce bias and obtain accuracy.

A consultant pattern is a small subset of the general inhabitants, exhibiting the identical traits as

that total inhabitants. Additionally it is a prerequisite to legitimate statistical induction, or quantitative generalization. Consultant sampling is crucial for profitable averaging of random errors and avoidance of

systematic errors, or bias. With random sampling, each specimen of the inhabitants ought to have an equal

probability of being included within the pattern. There are standardized strategies for conducting random sampling to acquire a consultant pattern. Generally, nonetheless, random sampling is just not possible, and the

outcomes might subsequently not be in keeping with the general inhabitants and be freed from bias.

Presenting and Analyzing Outcomes — Trendy science virtually at all times employs a statistical Assessment to

interpret knowledge. Reference the Lab 1 background for steering on choosing applicable graphic methodology and mathematical Assessment of the information. These interpretations are quantitative in nature and permit the scientist to

decide whether or not the experimental outcomes point out a constant development or situation.

Interpretations may be qualitative in nature. As an illustration, a speculation predicted that there was fecal

coliform in a neighborhood stream and, after repeated testing, none was discovered. This might be qualitatively

interpreted that there’s an insignificant quantity of fecal coliform within the stream. Any such qualitative interpretation leaves room for errors in judgment.

Step 5 – Interpret the outcomes and draw conclusions ➔ settle for, revise, or reject the speculation

When statistical analysis of experimental outcomes is carried out, there’ll both be a statistical distinction

between the examined topic and a management group (helps speculation HA) or there can be no distinction

between the examined topic and the management group (helps null speculation H0). Missing statistical

analysis requires that the mathematical Assessment and/or qualitative outcomes be interpreted to find out

whether or not the speculation is accepted, modified, or rejected.

For instance, the dedication of an insignificant quantity of fecal coliform in a stream might be interpreted because the water is secure to drink. However would you are feeling secure consuming the stream water?

• Speculation Accepted – If the speculation is accepted, the coed will write a proper report and

contribute this work to the present scientific literature. The report will make it doable for different scientists (on this case, different college students, or the trainer) to guage work for scientific soundness

and to repeat the experiment to confirm the outcomes. This course of is called peer evaluate.

• Speculation Rejected – If the speculation is rejected, the coed will write a proper report and

contribute this work to the present scientific literature. Vital data will be gained from concepts that fail. This makes it doable for the unique researcher or different college students to research the

similar matter and to construct upon the rejected speculation from the previous investigation. Edison, for

instance, didn’t invent the sunshine bulb. Over a yr and a half, Edison considerably improved upon a

fifty-yr previous concept. In creating an electrical lighting system that contained all the weather essential to make the incandescent mild sensible, secure, and economical for dwelling use, Edison discovered 10,000 methods

that might not work.

Revised: August 7, 2019 6

Step 6 – Reporting the outcomes

Outcomes of scientific analysis should be shared to finish the cycle of the scientific methodology and stimulate

additional thought, permit testing of the strategies and outcomes, and make sure the alternative for potential improvement from speculation to corroborated speculation to scientific idea or maybe even recognition

of a scientific truth or pure legislation. A number of frequent strategies of reporting are used:

◼ Formal memorandum

◼ Formal laboratory reviews

◼ Peer reviewed scientific articles

Formal Memorandum

The customary reporting format for a lot of state and federal businesses, in addition to in trade, is a proper

memorandum. An extended report format can also be frequent. The formal memorandum follows the next

format. You should definitely point out the content material of every part of the memo by utilizing the respective labels (i.e.,

Label sections as: Background, Investigation, Conclusions and Suggestions).

MEMORANDUM

To: (point out the identify of the receiver – if an company, additionally embrace formal title and company

identify)

From: (point out your identify)

Date: (date memorandum is being submitted)

Topic: (description of the content material of the memo, for instance: Assessment of fecal coliform content material

of Turtle Creek, Dallas County, Texas)

Background: Concise paragraph (or extra if wanted) to stipulate:

◼ The place (reference map), when and why the examine was carried out

◼ present normal background data on the examine space

Investigation: Paragraphs factually outlining and presenting the next:

◼ what assessments had been carried out

◼ summarize the outcomes and current in desk and or graphic kind – NOTE: these must be labeled appropriately and referenced in your abstract

◼ uncertainties

Conclusions: Concise abstract of your interpretations and conclusions, together with whether or not there

is sufficient proof to behave.

Advice(s): Itemize and help your suggestions (for instance, what motion must be undertaken to reply to the state of affairs or what additional motion could also be

wanted to develop sufficient proof to help taking actions)

Attachment(s): An inventory of connected paperwork (e.g., figures, tables, graphs) which can be connected in

order on the finish of the memorandum – NOTE: all included figures, tables,

graphs or maps MUST be appropriately referenced and defined within the

doc.

Revised: August 7, 2019 7

Formal Laboratory Experiences

Normal Feedback: Writing is among the most essential issues you’ll do within the laboratory. All formal

laboratory reviews should be typed and submitted in exhausting copy. Good communication is crucial. Due to this fact, good grammar, appropriate spelling and phrase selection, in addition to paragraph construction are crucial. When you

have written your laboratory report, re-learn and edit it to develop a nicely-written doc. Make use of

the Faculty Writing Lab that can Help you edit your written doc and enhance your writing abilities.

Every of the next sections must be included in your report. Every part ought to start with the identify

of the part in ALL CAPS. It’s possible you’ll evaluate “Labwrite” as a useful resource that can Help you put together, manage, interpret and write a proper laboratory report < http://labwrite.ncsu.edu/ >

1. TITLE – Select a title that describes the speculation you might be testing. It’s possible you’ll wish to use the unbiased variable and the dependent variable in your title (e.g., The Results of Ozone on

Ultraviolet Radiation).

2. INTRODUCTION – Establish the phenomenon you studied/examined and supply related background data (e.g., why are you doing this experiment, what preliminary observations or

questions led to this line of analysis and to your particular experiment, what’s the environmental

significance?) This dialogue will possible embrace data from different

research/paperwork/sources which should be correctly referenced and cited.

three. HYPOTHESIS – State the speculation that your experiment was designed to check; the speculation must be particular, presenting the unbiased variable and the anticipated end result within the dependent variable. For instance: Precipitation with a pH of three.6 will lead to 20 p.c decrease charges of seed

germination of purple maple (Acer rubrum). Presentation of the speculation might use the formal IF-

THEN speculation assertion indicating the anticipated relationship between the dependent variable and the unbiased variable (e.g., If there’s extra ozone within the higher environment, then much less

ultraviolet mild will attain the floor of the earth.). The speculation might mirror a predicted

rating of outcomes. For instance, For brine shrimp uncovered to growing concentrations of three

chemical substances, Chemical A may have the bottom LC-50 (most poisonous), Chemical B may have the very best LC50 (least poisonous), and Chemical C may have intermediate toxicity.

four. MATERIALS AND METHODS – Describe precisely how and while you carried out your experiment. Embrace sufficient element on experimental design, experimental equipment/gear, strategies of gathering and analyzing knowledge, and varieties of experimental management so that somebody

studying your report might precisely repeat your experiment. Steps must be mentioned in

chronological order. Use diagrams or drawings if they might Help the reader perceive and replicate the experiment (see feedback beneath 5. RESULTS for easy methods to establish such illustrations).

Describe any supplies or gear you used, once more with sufficient element to allow somebody to

repeat your experiment. This part must be written in previous tense and lively voice as work

accomplished (e.g., We crammed every of three petri dishes with 20 ml of faucet water.).

5. RESULTS – Report the outcomes of your experiment. Current your observations / knowledge with NO interpretations or conclusions about what they imply. You need to have textual content on this part,

supported utilizing tables, graphs and/or charts to help in presenting the outcomes. Embrace a dialogue of uncertainties.

You should definitely make particular reference to all such tables, graphs, pictures, drawings, diagrams,

maps, and so forth. Additionally report the outcomes of any statistical assessments. All tables or different varieties of illustrations

must be numbered (within the order through which they’re referenced within the textual content and may have an applicable title. Tables are recognized above the desk. All different illustrations are known as

figures and are captioned beneath the illustration. This part must be written in previous tense as

work accomplished.

Embrace in a desk each knowledge level you collected in your experiments, except you collected

greater than 100 knowledge factors. If there have been greater than 100 knowledge factors, you might save area and report

solely the variety of factors and the related averages or means.

http://labwrite.ncsu.edu/
Revised: August 7, 2019 eight

6. DISCUSSION – Clarify what your knowledge and outcomes imply. Describe patterns and relationships that emerged. Clarify how any modifications to or issues with the experimental design/process might have affected the outcomes. Think about the next questions: is it conclusive as a take a look at of your

speculation? Focus on doable sources of error in your experiment? Does the experiment should be

repeated earlier than drawing conclusions about your speculation? How do your outcomes evaluate with

the outcomes of earlier analysis on the identical topic? What additional questions do the outcomes of your experiment elevate? What experiment(s) must be performed subsequent?

7. CONCLUSION – Briefly summarize what you probably did, why you probably did it, and what occurred. This could embrace a quick assertion indicating whether or not your speculation was supported or not supported. If applicable, suggest a modified speculation.

eight. LITERATURE CITED – Alphabetical record of books, publications, paperwork, or web pages you consult with that help statements you make in your report. Within the physique of the report, in-textual content

referencing to those sources is given by giving the creator and yr of publication inside parentheses on the finish of the sentence which incorporates the cited data.

• Within the reference citations, for an internet site, you’ll want to give the COMPLETE URL for the webpage (do NOT simply record the principle web site) from which you obtained your

data!!! DO NOT put the URL within the in-textual content reference. For instance, the data that “17,694 mills produced 30 million tons of hazardous waste within the

United States” is derived from the U.S. Environmental Safety Company however it is going to NOT

be discovered at: http://www.epa.gov/ and this essential EPA web site ought to NOT be cited because the supply. Relatively, the statistic is discovered at: http://www.epa.gov/epaoswer/osw/tsds.htm and

that is the whole URL that must be included in your reference quotation.

Examples are offered under for the format you must use within the precise alphabetical record of all literature cited.

BOOK:

Junger, S. 1997. The Excellent Storm. HarperCollins, New York. 301pp. (record particular pages or a chapter for those who

solely used the e book to consult with particular data on a couple of pages, eg., if we had been itemizing this e book just for its reference to the tragedy of the commons and the swordfish fishery, we would add “see p. 83-84”)

CHAPTER IN EDITED BOOK WITH DIFFERENT AUTHOR FOR EACH CHAPTER:

Miller, J.E. 1988. Results on photosynthesis, carbon allocation, and plant development related to air pollutant

stress. Pages 287-316 in Heck, W.W., O.C. Taylor, and D.T. Tingey (eds.), Assessment of Crop Loss

from Air Pollution. Elsevier Utilized Science, New York. 552pp.

ARTICLE IN MAGAZINE OR JOURNAL:

DuBay, D.T. 1996. Work your plan, plan your work: North Carolina’s Environmental Schooling Plan. Pal

of Wildlife – The Journal of the North Carolina Wildlife Federation 44(three):10-11. (Summer time 1996)

Ehrlich P.R., Murphy D.D., M. C. Singer, M.C., Sherwood, C.B., White, R.R. and Brown, I.L. 1980.

Extinction, discount, stability and enhance: The responses of checkerspot butterfly (Euphydryas) populations to the California drought. Oecologia 46(1): 101-105. (July 1980

INTERNET WEB SITE (Citations for Web web sites must be like print media citations, together with

creator or sponsoring company, publication date, article title, web site title, URL, the date the data was

posted, and the date when the net deal with was accessed to acquire the data.):

North Carolina State College. 2004. Labwrite for College students – Enhancing Lab Experiences. Sponsored and

funded by Nationwide Science Basis. http://labwrite.ncsu.edu/index.html

Plaisance, S. 2006. Wasps Launched in Louisiana to Fight Bugs. Environmental Information Community, Inc., San Francisco. < http://www.enn.com/right now.html?id=11430 > posted October 12, 2006, accessed November

four, 2006.

http://www.epa.gov/
http://www.epa.gov/epaoswer/osw/tsds.htm
http://labwrite.ncsu.edu/index.html
http://www.enn.com/right now.html?id=11430

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seventh of August, 2019 1st of August, 2019 1st of August, 2019 1

ENVR 1401 – INTRODUCTION

1st Lab – Scientific Method

Aims of Studying:

1. Describe the scientific methodology’s steps.

2. Establish and doc testable observations.

three. Separate dependent and unbiased variables.

four. Arrange, acquire, and current scientific knowledge.

Overview

This exercise investigates the scientific methodology’s idea and implementation. To discern between precise trigger and impact

Relationships derived from associations or perceptions, in addition to phenomena, should be studied via the usage of nicely-designed experiments.

making thorough observations that others can replicate

The scientific methodology is often known as a structured, linear process that entails the next steps and requires specialised abilities:

1. Make observations or acquire knowledge, which continuously results in a Question Assignment

2. Assemble a speculation that results in a prediction.

three. Design an applicable take a look at/experiment to

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