Name: measuring protein concentration with absorbance
Uploaded: 2023-04-30T06:31:14.000Z
Duration: 8 min 49 s
Channel: JoVE

K12 Standards

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Waves and Their Applications in Technologies for Information Transfer

HS-PS4-4

Photometric Protein Determination

タンパク質の吸光光度定量

濃度の測定は、多くの生化学的な試金の基本的なステップです。タンパク質の吸光光度定量活用という事実をサンプルに光吸収物質が含まれていますより多く、少ない光は、それを送信します。濃度と吸収との関係は線形なのでこの現象使用できます試料中濃度を測定する不明です。
このビデオでは、タンパク質の吸光光度定量法の基本を解説し、ブラッドフォードの試金および Lowry 方法を紹介します。ビデオの手順は一般的なブラッドフォードの試金をカバーします。覆われているアプリケーションには、核酸濃度・純度を特徴付けるための量が非常に少ない、バイオミメティック材料の効率と Remazol 色素を用いたタンパク質の吸光光度定量の別のバリエーションを結合の決定の直接測定が含まれます。
<div class="chapter_text" id="script_0">
	多くの生化学的な試金の基本的なステップは、サンプル中のタンパク質の濃度を決定します。小さなサンプル サイズの吸光光度定量を行うことができます。サンプルに光吸収物質が含まれていますより多く、それを介して光を送信少ない。これは吸収物質の量的な測定を提供します。これらの概念は、2 つのテクニックを紹介する記事は、すべての時間の 3 つの最も引用されたペーパー科学にとても基本的です。定量方法、実行方法、および収集したデータの分析方法、このビデオは最も一般的な吸光光度タンパク質のいくつかの背後にある概念が表示されます。
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<div class="chapter_text" id="script_1">
	フォト メトリックのタンパク質の定量は、濃度と光の吸収との関係に基づきます。これは光吸収の種の集中はその吸光度に比例してビール-ランベルトの法則として知られています。
	この原則は、すべてのタンパク質の吸光光度定量法を基づいています。
	直接吸光分析、不変の蛋白質のサンプルの吸光度値が計測されます。トリプトファンとチロシン残基、芳香族の側鎖のため波長 280 で最高の吸光度の測定値に与える nm。
	ただし、これらのアミノ酸を 2 つの最も頻繁に見られるタンパク質は各決定がユニークなのですべての蛋白質のさまざまな量で存在します。この制限より複雑なアッセイを克服するために-これらのアミノ酸に依存していない-を開発しました。
	1 つの例はサンプルに着色された染料を追加する位置のブラッドフォードの試金です。という Coomassie 青い染料は、それに比例してより多くのタンパク質、染付詳細バインド イベントを応答します。
	594 で光を吸収するバインドされた Coomassie 青い色素の吸光度を測定することによって蛋白質の集中の決定、nm。しかし、ブラッドフォードの試金は集中の短い範囲に線形希釈はしばしば解析の前に必要なのでです。
	Lowry 法は、ビウレットの試薬、ペプチド結合と反応して銅イオンと芳香族アミノ酸の酸化 Ciocâlteu Folin 試薬のアルカリ溶液を組み合わせたものです。サンプルの結果の色の変化はタンパク質濃度に比例します。
	750 に減らされた Folin 試薬の吸光度を判断できる nm。直接吸収のような各蛋白質はユニークな応答には、興味の蛋白質のためにキャリブレーションする必要があります。今、我々 は、最も一般的なアッセイの背後にある基本的な原則を確認したところ、吸収とブラッドフォードの試金の実行方法直接見てみましょう。
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<div class="chapter_text" id="script_2">
	直接吸光分析するには、ゼロの吸光度を決定する空白を分光光度計を校正します。標準的なソリューションは、検量線の作成に使用、調理されます。その後、最初の標準の因数は、キュベットに追加、分光光度計に配置。
	吸光度値 280 nm が記録されます。このプロセスは、実行ごとにきれいなキュベットを使用して、それぞれの標準の繰り返されます。完了すると、検量線は濃度と吸光度をプロットすることによって作成されます。この直線の傾きは、濃度を吸光度を関連するモル減衰係数です。
	次に、未知のサンプルは、キュベットに追加され、吸光度値が記録されます。同様に別の吸光光度定量法のデータ解析と同様、ブラッドフォードの試金を見ているカバーします。
	ここでは、ブラッドフォード蛋白質の試金は 96 ウェル プレートに BSA の標準で実行されます。まず、BSA 在庫ソリューションを用意しています。
	未知のソリューションは、濃度の試金の範囲内で確実に脱イオン水で希釈しました。キットによって Coomassie の染料はまた希釈を必要があります。その後、検量線は 96 ウェル プレートに BSA の基準を追加することによって設定されます。
	脱イオン水は、標準曲線の生成に必要な濃度に達するに追加されます。未知のサンプルは、トリプリケート正確な測定を使用するために、プレートを追加必要があります。Coomassie 色素が追加されます次に、ピペットを混ぜて、各ウェルに。
	脱イオン水は、空白、吸光度を測定すると、空のウェルに追加されます。590 でプレート リーダーにバインドする染料のための 5 分を待機した後、吸光度を測定 nm。
</div>
<div class="chapter_text" id="script_3">
	今では、いくつかのアッセイを実行した、データを分析する方法を見てみましょう。各フォト メトリック タンパク質定量法は、ビール ランベルトの法則に基づいています。
	基準の測定した吸光度を使用を使用して、未知試料の濃度を決定する検量線を作成します。この曲線は、プロットされます手動で、すべての標準を測定した後、新しい吸光光度ツールは較正曲線を作成する作業も。未知サンプルを分析、これらのシステムはまた蛋白質の集中を計算します。
</div>
<div class="chapter_text" id="script_4">
	今ではタンパク質の吸光光度定量データを分析する方法を確認しましたところ、いくつかのこれらの手順は、利用方法を見てみましょう。
	核酸濃度を直接測定するため、タンパク質の吸光光度定量の原理を使用もできます。Nanodrop 分光光度計は、光学活性な台座の上に非常に少量の試料を受け入れます。吸光度を測定し、システムは自動的に核酸の濃度を決定します。サンプルの純度が 280 に 260 の分析によって決定されます測定蛋白質と他の情報源を妨害することができます、ため nm と 230 に 260 nm の吸光度比。純粋な核酸通常降伏比約 1.8 と 2.0 約 DNA および RNA のそれぞれ。
	フォト メトリックのタンパク質の定量は、細胞の特定の応答を引き出すために自然からインスピレーションを得た、バイオミメティック材料の生産にも使用できます。組換えアドヘシンは宿主細胞に細菌の付着をシミュレートするポリスチレンのビードにバインドされます。ブラッドフォードの試金は、バイオミメティック材料の生産にビーズに組換えの接着結合効率を決定するためです。
	代替測光蛋白質の試金は、検出と抗菌剤タンパク質の解析で使用できます。鮮やかなブルーの Remazol R 染料は熱殺された細菌を帯び。抗菌蛋白質は染めのソリューションで孵化します。その後、サンプルを遠心分離すると、595 で上清の吸光度とマイクロ プレート分光光度計を用いて nm。増加吸光度、培養上清をラベル付きの細菌からリリースされた水溶性色素、酵素活性の定量測定。
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<div class="chapter_text" id="script_5">
	タンパク質の吸光光度定量にゼウスのビデオを見てきただけ。このビデオ吸光光度定量の基本原則を説明したいくつかの一般的な試金のための一般的な手順を行って、技術のいくつかの新しい進歩をカバーします。見てくれてありがとう!
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Measuring the concentration is a fundamental step of many biochemical assays. Photometric protein determination takes advantage of the fact that the more ...

サンプル中のタンパク質の濃度を測定することは、多くの生化学アッセイにおける基本的なステップです。測光測定は、小さなサンプルサイズで行うことができます。サンプルに含まれる光吸収物質が多いほど、光がサンプルを通過する光は少なくなります。これにより、吸収物質の定量的測定が可能になります。これらの概念は科学にとって非常に基本的なものであり、そのうちの2つの手法を紹介した記事は、史上最も引用された3つの論文に含まれています。このビデオでは、最も一般的な測光タンパク質測定技術の背後にある概念、それらがどのように実行されるか、および収集されたデータがどのように分析されるかを示します。フォトメトリックタンパク質の測定は、濃度と光吸収性の関係に基づいています。これはランベルトベールの法則として知られており、光を吸収する種の濃度はその吸光度に比例すると述べています。この原理は、すべての測光タンパク質測定法の基礎となっています。直接吸収分析では、未修飾のタンパク質サンプルの吸光度値が測定されます。トリプトファン残基とチロシン残基は、芳香族側鎖があるため、280nmの波長で最高の吸光度測定値が得られます。しかし、これらのアミノ酸は、タンパク質の中で最も頻度の低い2つであり、すべてのタンパク質に異なる量で存在するため、各測定は異なります。この制限を克服するために、これらのアミノ酸に依存しない、より複雑なアッセイが開発されました。一例は、着色色素をサンプルに添加するBradford Assayです。クマシーブルーとして知られるこの染料は、タンパク質が多ければ多いほど、色素との結合イベントが多くなるほど、比例して反応します。次に、594 nmで光を吸収する結合したCoomassie Blue色素の吸光度を測定することにより、タンパク質濃度を決定します。ただし、Bradfordアッセイは短範囲の濃度で直線的であるため、分析前に希釈が必要になることがよくあります。Lowry法は、銅イオンをアルカリ性にしてペプチド結合と反応させるBiuret試薬と、芳香族タンパク質残基を酸化するFolin-Cioc?lteu試薬を組み合わせたものです。結果として生じるサンプルの色の変化は、タンパク質濃度に比例します。還元されたFolin試薬の吸光度は、750 nmで測定できます。直接吸収と同様に、各タンパク質には独自の応答があり、目的のタンパク質に合わせて調整する必要があります。さて、最も一般的なアッセイのいくつかの背後にある基本原理を確認したので、直接吸収とブラッドフォードアッセイがどのように行われるかを見てみましょう。直接吸収分析を開始するには、分光光度計をブランクで校正して吸光度がゼロかどうかを判断します。検量線の作成に使用するための標準溶液が用意されています。次に、最初の標準のアリコートをキュベットに加え、分光光度計に入れます。次に、280 nmでの吸光度値を記録します。このプロセスは、各標準に対して繰り返され、実行ごとに清潔なキュベットを使用します。完了すると、吸光度と濃度をプロットして検量線が作成されます。この線の傾きはモル減衰係数であり、吸光度と濃度を関連付けます。次に、未知のサンプルをキュベットに加え、吸光度値を記録します。異なる測光測定法のデータ分析は類似しているため、Bradfordアッセイを見た後にそれについて説明します。ここでは、Bradfordタンパク質アッセイをBSA標準試料を用いて96ウェルプレートで実施します。まず、BSAストック溶液を準備します。未知化合物の溶液を脱イオン水で希釈し、濃度がアッセイの範囲内にあることを確認します。キットによっては、クマシー染料も希釈が必要な場合があります。次に、BSA標準試料を96ウェルプレートに添加することにより、検量線を設定します。脱イオン水は、標準曲線を生成するために必要な濃度に達するまで追加されます。未知のサンプルは、正確な測定が行われるように、プレートに3回で追加する必要があります。次に、クマシー染料を各ウェルに加え、ピペットと混合します。脱イオン水は、吸光度を測定するために、空の井戸にブランクとして加えられます。色素が結合するまで5分間待った後、吸光度をプレートリーダーで590nmで測定します。いくつかのアッセイを実行したので、データの分析方法を見てみましょう。各測光タンパク質測定法は、ランベルトベールの法則に基づいています。測定された標準試料の吸光度は、検量線を作成するために使用され、その後、未知のサンプルの濃度を決定するために使用されます。この曲線は手動でプロットできますが、すべての標準が測定されると、新しい分光光度ツールによって検量線が作成されます。これらのシステムは、未知のサンプルが分析されるときにタンパク質濃度も計算します。フォトメトリックタンパク質測定データの解析方法を確認したところで、これらの手順がどのように活用されているかを見てみましょう。光度タンパク質測定の原理は、核酸濃度を直接測定するためにも使用できます。nanodrop分光光度計は、光学的に活性な台座に非常に少量のサンプルを受け入れます。その後、吸光度が測定され、システムが自動的に核酸濃度を決定します。タンパク質やその他の供給源が測定に干渉する可能性があるため、サンプルの純度は、260 nm から 280 nm と 260 から 230 nm の吸光度比を分析することによって決定されます。純粋な核酸は、通常、DNAとRNAでそれぞれ約1.8と約2.0の比率をもたらします。光度タンパク質測定は、特定の細胞応答を誘発するために自然から着想を得た生体模倣材料の製造にも使用できます。組換えアドヘシンはポリスチレンビーズに結合し、宿主細胞への細菌の付着をシミュレートします。Bradfordアッセイは、生体模倣材料の製造におけるビーズへの組換え接着の結合効率を決定するために使用されます。代替のフォトメトリックタンパク質アッセイは、タンパク質抗菌薬の検出と特性評価に使用できます。レマゾールブリリアントブルーR色素は、熱死菌に共有結合しています。タンパク質抗菌剤は、染色溶液中でインキュベートされます。次に、サンプルを遠心分離し、マイクロプレート分光光度計を使用して595nmの上清の吸光度を測定します。標識された細菌から上清に放出される可溶性色素による吸光度の増加は、酵素活性の定量的測定です。JoVEのフォトメトリックタンパク質測定に関するビデオをご覧になりました。このビデオでは、測光測定の基本原理を説明し、いくつかの一般的なアッセイの一般的な手順について説明し、技術の新たな進歩を取り上げました。ご覧いただきありがとうございます!

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measuring protein concentration with absorbance

Measuring protein concentration with absorbance is a key step in many biochemical assays. Photometric methods use the fact that samples with more light-absorbing material transmit less light. Because concentration and absorption are directly related, this makes it possible to measure an unknown sample.

The core idea comes from the Beer-Lambert Law. This law states that the concentration of a light-absorbing species is proportional to its absorbance. The video also introduces the Bradford assay and the Lowry method, which are two common ways to measure protein without relying only on direct absorption.

Direct absorption analysis measures the absorbance of an unaltered protein sample. At 280 nm, tryptophan and tyrosine give the strongest readings because of their aromatic side chains. However, these amino acids are present in different amounts in different proteins, so each sample has to be treated on its own.

The Bradford assay solves that limitation by adding Coomassie Blue dye to the sample. The dye binds to protein, and the more protein present, the more dye binds. The bound dye is read at 594 nm, but the assay is linear only over a short range, so samples often need dilution before analysis.

The Lowry method uses two reagents. The Biuret reagent contains alkaline copper ions that react with peptide bonds, and the Folin-Ciocalteu reagent oxidizes aromatic residues. The resulting color change is proportional to protein concentration, and the reduced Folin reagent is measured at 750 nm. Like direct absorption, the method must be calibrated for the protein being tested.

A direct absorption run starts by blanking the spectrophotometer to set zero absorbance. Standard solutions are then measured in clean cuvettes at 280 nm, and the absorbance values are plotted to make a calibration curve. The slope of that line is the molar attenuation coefficient, and the unknown sample is measured against the same curve.

The Bradford assay is often done on a 96-well plate using BSA standards. The unknown samples are diluted with deionized water so they fall within the assay range, and the standards are added to build a standard curve. The unknowns are usually added in triplicate, Coomassie dye is mixed into each well, a blank well contains deionized water, and the plate is read after 5 min at 590 nm.

Data analysis for these assays is based on the same Beer-Lambert relationship. The standard readings create a calibration curve that is used to find the concentration of unknown samples. Some newer spectrophotometric systems build this curve automatically and calculate protein concentration as samples are analyzed.

These ideas also apply to other measurements. Very small amounts of nucleic acids can be measured with a Nanodrop spectrophotometer, which reads absorbance on an optically active pedestal and estimates concentration automatically. Sample purity is checked with the 260/280 and 260/230 absorbance ratios, which are typically about 1.8 and 2.0 for pure DNA and RNA, respectively.

Photometric methods are also used in biomimetic materials, which are inspired by nature to trigger specific cellular responses. In one example, recombinant adhesins are attached to polystyrene beads to mimic bacterial binding to host cells, and the Bradford assay measures coupling efficiency. Another variation uses Remazol brilliant blue R dye on heat-killed bacteria to detect protein antimicrobials by measuring dye released into the supernatant at 595 nm after centrifugation.

Measuring Protein Concentration with Absorbance

measuring-protein-concentration-with-absorbance

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electrophoretic-mobility-shift-assay-emsa

Detecting Protein-DNA Binding by EMSA

Electrophoretic mobility shift assay, or EMSA, is a biochemical method used to detect binding between proteins and nucleic acids. It is also called a gel shift assay. The test compares how a labeled nucleic acid moves through a gel before and after it binds a protein. EMSA is used to see whether a specific protein binds to a specific nucleic acid. First, the nucleic acid is labeled to make a probe. The transcript describes radioactive phosphorus-32 as a common label. The probe is then mixed...

photometric protein determination

Measuring protein concentration with absorbance is a key step in many biochemical assays. Photometric methods use the fact that samples with more light-absorbing material transmit less light. Because concentration and absorption are directly related, this makes it possible to measure an unknown sample. The core idea comes from the Beer-Lambert Law. This law states that the concentration of a light-absorbing species is proportional to its absorbance. The video also introduces the Bradford assay...

density gradient ultracentrifugation

Sucrose Gradient Separation in an Ultracentrifuge

Sucrose gradient separation in an ultracentrifuge is a lab method for isolating cell parts and biomolecules. It uses differences in density to make particles sink or rise in a liquid. A high-speed ultracentrifuge speeds up this process so components can be separated without destroying them. The basic idea starts with a suspension, which is particles mixed in a liquid solvent. Particles that are denser than the solvent sediment, while less dense particles float. A rotor inside the...

co-immunoprecipitation and pull-down assays

co-immunoprecipitation-and-pull-down-assays

Protein Interaction Capture Methods in Cells

Co-immunoprecipitation and pull-down assays are laboratory methods used to capture stable protein-protein interactions. Protein-protein interactions help control many biological functions, but many of them have not yet been identified. These assays are related to immunoprecipitation, which isolates a target protein from a mixed sample using an antibody. In co-immunoprecipitation, or CoIP, an antibody binds the target protein, and that protein is already attached to another protein that the...

reconstitution of membrane proteins

Membrane Proteins in Liposome Models

Membrane proteins can be moved into liposome models so their function can be studied outside a cell. Reconstitution means restoring an isolated biomolecule to a working form. For membrane proteins, that usually means placing a purified protein into an artificial lipid membrane. Cell membranes are made mainly of phospholipids and membrane proteins. The phospholipids form a bilayer with hydrophilic phosphate heads facing water and hydrophobic fatty acid tails facing inward. Some membrane...

f&#246;rster resonance energy transfer (fret)

FRET as a Molecular Ruler in Cells

Föster resonance energy transfer, or FRET, is a way to study close-range biochemical interactions using light-emitting molecules. A donor fluorophore can pass energy to an acceptor fluorophore when their emission and absorption spectra overlap. This transfer happens only when the pair is very close together, usually within 10 nm. Because FRET depends on distance, it is often called a molecular or spectroscopic ruler. The strength of the signal is measured as FRET efficiency, which describes...

surface plasmon resonance (spr)

SPR Biosensors for Tracking Binding Kinetics

Surface plasmon resonance, or SPR, is a way to track biomolecular binding on a label-free biosensor. It is used to measure molecular affinity, kinetics, specificity, and concentration. The method works with a thin metal layer on a prism, where changes in reflected light reveal interactions in real time. SPR sensors use a thin layer of a noble metal on the face of a prism. Light is reflected from the prism-metal interface into a photodetector. At one specific angle, called the surface plasmon...

biochemistry

このコレクションでは、親和性クロマトグラフィーなどの一般的に使用される精製方法や、MALDI-TOFなどの分析方法について紹介します。さらに、共同免疫沈降法や代謝標識法など、生体分子の相互作用や機能を評価する方法も紹介します。

Learn how absorbance helps measure protein concentration with the Bradford assay, Lowry method, and direct absorption, plus related nucleic acid and biomaterial uses.

Measuring Protein Concentration with Absorbance | JoVE K12

HS-PS4-5

new-york-state-science-learning-standards

New York State Science Learning Standards

HS. Structure and Properties of Matter

HS-PS1-10.

HS. Waves and Electromagnetic Radiation

HS-PS4-4.

HS-PS4-5.

Life Science

Structure and Function

HS-LS1-1.

matter-and-energy-in-organisms-and-ecosystems

Matter and Energy in Organisms and Ecosystems

HS-LS1-6.

Inheritance and Variation of Traits

HS-LS3-1.

Overview

Principles of Photometric Protein Determination

Execution of Assays

Data Analysis

Applications

Summary

Travelling Waves

A wave is a disturbance that propagates from its source, repeating itself periodically, and is typically associated with simple harmonic motion. ...

Wave Parameters

The simplest mechanical waves are associated with simple harmonic motion and repeat themselves for several cycles. These simple harmonic waves can be ...

Equations of Wave Motion

Mathematically, the motion of a wave can be studied using a wavefunction. Consider a string oscillating up and down in simple harmonic motion, having a ...

Graphing the Wave Function

Consider the wave equation for a sinusoidal wave moving in the positive x-direction. The wave equation is a function of both position and time. From the ...

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Velocity and Acceleration of a Wave

A wave propagates through a medium with a constant speed, known as a wave velocity. It is different from the speed of the particles of the medium, which ...

Speed of a Transverse Wave

The speed of a wave depends on the characteristics of the medium. For example, in the case of a guitar, the strings vibrate to produce the sound. The ...

/files/media/science-education/science-education-thumbs/14722.jpg

Kinetic and Potential Energy of a Wave

All forms of waves carry energy; this is directly visualized in nature. For instance, the waves of earthquakes are so intense that they can shake huge ...

Energy and Power of a Wave

The total energy associated with a wavelength is the sum of the potential energy and the kinetic energy. The average rate of energy transfer associated ...

Propagation of Waves

When a wave propagates from one medium to another, part of it may get reflected in the first medium, and part of it may get transmitted to the second ...

Sound Waves

Sound waves can be thought of as fluctuations in the pressure of a medium through which they propagate. Since the pressure also makes the medium&#39;s ...

Sound as Pressure Waves

Sound waves, which are longitudinal waves, can be modeled as the displacement amplitude varying as a function of the spatial and temporal coordinates. As ...

/files/media/science-education/science-education-thumbs/14724.jpg

Speed of Sound in Solids and Liquids

Most solids and liquids are incompressible&#8212;their densities remain constant throughout. In the presence of an external force, the molecules tend to ...

Speed of Sound in Gases

The speed of sound in a gaseous medium depends on various factors. Since gases constitute molecules that are free to move, they are highly compressible. ...

Doppler Effect - I

The Doppler effect and Doppler shift were named after the Austrian physicist and mathematician Christian Johann Doppler in 1842, who conducted experiments ...

Doppler Effect - II

The Doppler effect has several practical, real-world applications. For instance, meteorologists use Doppler radars to interpret weather events based on ...

Shock Waves

While deriving the Doppler formula for the observed frequency of a sound wave, it is assumed that the speed of sound in the medium is greater than the ...

Echo

The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More ...

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Electromagnetic Waves

James Clerk Maxwell formulated a single theory combining all the electric and magnetic effects scientists knew during that time, calling the phenomena his ...

Generating Electromagnetic Radiations

The German physicist Heinrich Hertz (1857&#8211;1894) was the first to generate and detect certain types of electromagnetic waves in the laboratory. ...

Electromagnetic Wave Equation

Maxwell&#39;s equations for electromagnetic fields are related to source charges, either static or moving. These fields act on a test charge, whose ...

propagation-speed-of-electromagnetic-waves

Propagation Speed of Electromagnetic Waves

Electromagnetic waves are consistent with Ampere&#39;s law. Assuming there is no conduction current Ampere&#39;s law is given as:


Consider a plane ...

Electromagnetic Waves in Matter

Electromagnetic waves can travel in the vacuum as well as in matter. For example light, which is an electromagnetic wave, can travel through air, water, ...

Energy Carried By Electromagnetic Waves

Anyone who has used a microwave oven knows there is energy in electromagnetic waves. Sometimes, this energy is obvious, such as in the summer sun&#39;s ...

The Wave Nature of Light

The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms ...

Use mathematical representations to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media. [Clarification Statement: Examples of data could include electromagnetic radiation traveling in a vacuum and glass, sound waves traveling through air and water, and seismic waves traveling through the earth.] [Assessment Boundary: Assessment is limited to algebraic relationships and describing those relationships qualitatively.]

HS-PS4-1

The Electromagnetic Spectrum

Electromagnetic waves are categorized according to their wavelengths and frequencies, giving the electromagnetic spectrum. These waves are classified as ...

Classification of Signals

Signals are categorized as Continuous-time or discrete-time, Periodic or aperiodic, Analog or digital, and Causal or noncausal.
A continuous-time signal ...

Discrete Fourier Transform

Consider a vibration sensor that continuously captures data in the form of a continuous time-dependent signal.
However, in reality, the sensor can only ...

Discrete-Time Fourier Series

The Discrete-Time Fourier Series is a counterpart to the Fourier-series expansion of continuous-time periodic signals.
Calculating the expansion ...

Sampling Theorem

Consider the continuous-time signal x(t), and a train of impulses where Ts,&#xA0; is the sampling interval, and fs, is the sampling frequency.
Multiplying ...

Properties of Fourier Transform I

In radio broadcasting, Fourier Transform properties are applied in simultaneous multi-channel transmission, adjusting audio clip speeds, live broadcast ...

Signal and System

Signals are sets of data or information.
One-dimensional signals include single-variable functions, such as the variations in air pressure over time in ...

Methods of Documentation VII: EMR

Electronic Medical Records (EMRs) primarily center around electronically documenting patients&#39; health information within a single healthcare ...

Fast Fourier Transform

The Fast Fourier Transform, FFT, is a computational algorithm for calculating the Discrete Fourier Transform by breaking the calculations into smaller, ...

reconstruction-of-signal-using-interpolation

Reconstruction of Signal using Interpolation

Consider a continuous signal and its sampled counterpart with a sampling period T.
Applying a zero-order hold to the sampled signal results in a piecewise ...

Downsampling

Consider a sampled sequence with zero values between sampling instants. Replace it by taking every N-th value of the sampled sequence.
The original and ...

Design Example

An engineer designs a circuit for a speaker system with a 2 kHz crossover frequency requirement, considering the speaker&#39;s resistance of 8 ohms.
The ...

Upsampling

Consider a decimated signal with a reduced frequency range due to its lower sampling rate.
Insert zeros between each sample to upsample, that introduces ...

Properties of DTFT I

Consider two discrete-time signals, each with their respective Discrete-Time Fourier Transforms DTFTs.
The signals are first multiplied by constants a and ...

Relation of DFT to z-Transform

The Discrete Fourier Transform (DFT) analyzes the frequency content of discrete-time signals.
It maps the N-sampled discrete time-domain sequence to its ...

Feedback control systems

Feedback control systems are categorized as linear or nonlinear, time-varying or time-invariant, and classified by signal types as continuous or ...

Properties of the z-Transform I

Certain properties provide a solid foundation for analyzing discrete-time systems using the Z-transform.
Considering two discrete-time signals, the ...

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is a noninvasive medical imaging technique based on a phenomenon of nuclear physics discovered in the 1930s, in which ...

Evaluate questions about the advantages of using digital transmission and storage of information. [Clarification Statement: Examples of advantages could include that digital information is stable because it can be stored reliably in computer memory, transferred easily, and copied and shared rapidly. Disadvantages could include issues of easy deletion, security, and theft.]

HS-PS4-2

Interference and Superposition of Waves

When two waves of the same nature occur in the same region simultaneously, they result in interference. Interference of waves implies that the net effect ...

Sound Waves: Interference

Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure ...

Interference: Path Lengths

Consider two sources of sound, that may or may not be in phase, emitting waves at a single frequency, and consider the frequencies to be the same.
Two ...

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concept-of-resonance-and-its-characteristics

Concept of Resonance and its Characteristics

If a driven oscillator needs to resonate at a specific frequency, then very light damping is required. An example of light damping includes playing piano ...

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Sound Waves: Resonance

Resonance is produced depending on the boundary conditions imposed on a wave. Resonance can be produced in a string under tension with symmetrical ...

Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be described either by a wave model or a particle model, and that for some situations one model is more useful than the other. [Clarification Statement: Emphasis is on how the experimental evidence supports the claim and how a theory is generally modified in light of new evidence. Examples of a phenomenon could include resonance, interference, diffraction, and photoelectric effect.] [Assessment Boundary: Assessment does not include using quantum theory.]

HS-PS4-3

Measuring Protein Concentration with Absorbance

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