Name: fast and accurate exhaled breath ammonia measurement
Uploaded: 2014-06-11T14:00:00.000+00:00
Duration: 6 min 27 s
Description: Watch this Scientific Journal Video about Fast and Accurate Exhaled Breath Ammonia Measurement at JoVE.com

Yazarlar, Ulusal Bilim Vakfı (NSF) mali destek &quot;Sağlık ve Çevre için Orta-Kızılötesi Teknolojileri (MIRTHE)&quot; başlıklı EEC-0540832 hibe kabul

Araçların 1. Hazırlanması <ol><li> Amonyak optik sensör platformu, lazer diyot denetleyici, özel inşa kontrol elektroniği ünitesi (CEU), nefes örnekleyici, hava pompası, ve dizüstü bilgisayar, harici güç kaynağı açın. </li><li> Amonyak sensörü egzoz ve soğutma fanları hem çalışıp çalışmadığını kontrol edin. NOT: Bir sensörün arka bulunan, ikinci kolayca erişilebilir sensör, içinde bulunur. </li><li> Akustik algılama modülü ve iğne vana sıcaklık amonyak sensörü kutusunun tarafında bulunan dijital göstergeyi kontrol ederek 38.0 ° C&#39;de olduğundan emin olun. Sensör stabilize etmek için sıcaklık için güç sağlanan zaman yaklaşık 35 dakika bekleyin. </li><li> Bir simge isim nefes numune masaüstünde bulunan &quot;değişimi t&quot; tıklayarak 55 ° C giriş tüp ve ağızlık sıcaklığı ayarlayın. Daha sonra sıcaklık &quot;Upd tıklayarak takip yukarı veya aşağı oku tıklayarak değiştirilebilir&quot;Temp yedik. Masaüstüne dönmek için &quot;Exit&quot; ı tıklayın. Sistem stabilize etmek için sıcaklık için en az 5 dakika izin verin. 55 ° C&#39;de numune ve boru ısısını amonyak yüzey kaybını en aza indirir. </li><li> Amonyak sensörü kontrol laptop yazılımını açın. Program masaüstünde &quot;NH 3 Nefes Sensör Programı&quot; adlı bir klasör içinde ulaşılabilir. Bu klasör içinde, kullanıcı simgesini &quot;ana labview yazılım&quot; seçmelisiniz. Bu klasör çeşitli uygulamaları içerir, ancak kullanıcı istenen arayüzüne erişmek için &quot;Mainsequence.vi&quot; seçmelisiniz. Ekranın sol üst köşesindeki &quot;Çalıştır&quot; seçeneğini seçin. NOT: Bu kalibrasyon dizisi kilitleme satır başlar. QEPAS monitörün Lazer otomatik hat-kilitleme prosedürü sırasında seçilmiş optimal akım, çalışır. Bu işlem yaklaşık 25 dakika sürer. </li><li> Örnekleyicideki yeni bir oturum oluşturma şekilde adetch konu oturumu bağlı bir flash sürücüye kaydedilir kendi dosyası vardır. NOT: Bu numune masaüstünde bulunan programı &quot;Nefes Sampler&quot; açarak yapılır. Uygun oturumu tanımlamak alanı var. Oturumu sırasında oluşturulan tüm veriler bu tanımlayıcı altında flash sürücüye kaydedilir. Deneyin tarih tipik olarak dosya adının bir parçası olarak kullanılır. Giriş ve ağızlık sıcaklığının nefes numune alma programı girmeden önce ayarlanmalıdır. </li><li> Giriş borusu yeni bir tek kullanımlık ağızlık yerleştirin. Parmaklardan amonyak ile ağızlık kirlenmesini önlemek için tek kullanımlık eldiven giyin. </li></ol> 2.. Nefes Örnek Toplama NOT: İlgili Kurumsal Değerlendirme Kurulu (Etik Kurulu), insan denekler içeren herhangi bir çalışma onaylaması gerekir. Büyük ölçüde nefes amonyak etkileyebilecek pek çok faktör vardır. Bu faktörler doğrudan tarafından nefes amonyak ölçümleri değiştirebilirsistemik amonyak seviyelerini ffecting veya enstrümantasyon akciğerlerden nefes metabolitleri yolculuk etkileyerek. <ol><li> Konular girişte yaklaşık 12 saat boyunca ve test öncesinde egzersiz sabah kaçındı var ki hiçbir yiyecek tüketmiş olan, bir açlık durumda laboratuara gelmesi emin olun. </li><li> Hiçbir madde, veri toplamadan önce en az 1 saat boyunca, ağız içine getirilmiştir emin olun. Denekler test 1 saat önce daha da dişlerin daha büyük fırça emin olun. </li><li> Amonyak sensörü önünde konuyu koltuk. Giriş borusunu tutun, ve onlar amonyak kontaminasyonu önlemek için ağızlığı dokunmayın emin olmak için konuyu söyleyin. </li><li> Örnekleyici arayüzünde &quot;Başlat&quot; düğmesine tıklayın. Konu sürece onlar gibi için ağızlık içine nefes, ya da operatör yeterli olması numuneyi gördüğü kadar var. NOT: Bu en az 10 saniye süren bir tek tam nefes olduğunu. Ağız basınç bir vekil olarak gerçek zamanlı olarak ölçülürakış hızı için. Bir renk kodlu basınç göstergesi özne üretmek yardımcı olur ve 50 ml / sn bir soluma akış hızını temsil suyun 10 cm istenilen soluk basıncını korumak. Bu Fe NO belirlemek için protokol için ATS / ERS tarafından kabul beri bu akış hızı seçildi. Bu soluma akış hızı çocuklar ve yetişkinler tarafından başarılabilir. Aynı şekilde, üç tekrarlanabilir ekshalasyonlar az% 10 farklı olduğu alınmalıdır. </li><li> Nefes örneği tamamlandığında örnekleyici arayüzünde &quot;Dur&quot; tıklayın. </li></ol> 3.. Nefes Numune Ölçümü <ol><li> Bir nefes örneği analiz edildikten sonra, monitör çalışırken laboratuar teknisyeni o nefes profilinin herhangi bir segment analiz yeteneğine sahiptir. Ilgi nefes kısmı faz III bölümdür. Bu karbon dioksit konsantrasyonunda bir &quot;yayla&quot; ile karakterize edilir ve bre geç aşamasında ortada bulunanath. </li><li> Doğru nefes basınç düşümü önce zaman karbondioksit yaylaları başlar ve durdurmak için örnekleyici arayüzünde dikey çizgileri sürükleyerek numunenin faz III bölümünü seçin. Açıklama için Bkz: Şekil 1.. </li><li> Örnekleyici dokunmatik ekran arayüzü üzerinde &quot;Mağaza&quot; tıklayarak flash sürücüye verileri kaydetmek. </li><li> Nefes verileri saklandıktan sonra, kullanıcı yeni bir nefes numunesi başlatmak için &quot;başlangıç&quot; seçebilirsiniz. </li></ol> 4. Nefes Amonyak Mouth durulayın ve pH etkilerini gösteren <ol><li> Temel amonyak seviyesini oluşturmak için 3. nefes Örnek. Nefesler birbirinden en az 5 dakika alınır emin olun. </li><li> 60 saniye için bir su 30 mi kısım ile iyice ağız çalkalayın. </li><li> Durulama (Bölüm 2) 60 saniye içinde bir nefes numunesi toplayın. Zaman içinde amonyak değişikliği gözlemek için bir sonraki saat boyunca nefes örnekleri toplamak. NOT: Samples her dakika kadar sık ​​alınabilir, fakat tipik olarak daha büyük zaman aralıkları kullanılır. </li><li> 60 saniye için bazik bir solüsyon 30 ml alikotu (su içinde sodyum bikarbonat) ile iyice yıkayın ve ağız 4.2.1 tekrarlayın. </li><li> 60 saniye için asidik çözelti bir 30 ml alikotu ile iyice yıkayın ve ağız 4.2.1 tekrarlayın. </li></ol> 5.. Nefes Amonyak Inlet ve Ulaştırma Boru Sıcaklıkların etkilerini gösteren <ol><li> Giriş sıcaklığı ile 15 dakikalık bir süre boyunca Örnek, üç nefes vücut sıcaklığı, yaklaşık 30 ° C&#39;nin altında ayarlanmış </li><li> Nefes sampler&#39;ın dokunmatik ekran arayüzü üzerinde bir masaüstü simgesini kullanarak sırasıyla 55 ° C giriş ve taşıma boru sıcaklıklarını artırın. Sistem en az 5 dk kararlı duruma ulaşmak için izin verin. </li><li> 5 dk arayla ısıtılmış girişine Numune 3 nefesler. </li></ol>

<ol>
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Dr. Risby serves as a consultant for Loccioni Humancare the manufacturer of the breath sampler.

Gerçek zamanlı izleme metabolitleri tespit edebilen bir non-invazif yararları açıktır. Ancak, nefes araştırma alanında bu potansiyeli yerine getirmek için mücadele etti. Nefes ölçüm birçok karıştırıcı faktörler savunmasız dinamik bir süreçtir. Bizim yaklaşım önemli artıları vardır: özellikle, nefes örnekleyiciye birleştiğinde Rice QEPAS dayalı amonyak monitörün hassasiyet ve hız doğru ölçümü germane nefes toplama faktörleri değerlendirmek ve tanımlamak için bize sağlamış...

Amonyak protein metabolizması 1 bir yerde yan ürünü. Amonyak ölçümü nedenle klinisyenler, çeşitli hastalık ve sağlık durumları 2 değerlendirmeye yardımcı olabilir. Ancak, amonyak çok reaktif olduğundan, kan ya da nefes yoluyla doğru ölçülmesi zordur. Yaygın olarak kullanılan rağmen, kan deneyleri, 3 doğruluğu ile ilgili temel sorunlardan dahil olmak üzere sayısız dezavantajları vardır. Ancak kan tahlilleri ile büyük sorun onlar sadece hiç episodically toplanan gerçektir. Amonyak fizyolojisi, çok kan glukoz ve diğer birçok metabolik süreçler gibi, akışkan ve sürekli 4 değişiyor, çünkü bu önemlidir. Buna karşılık, nefes deneyler böylece kolayca tekrarlanan önlemleri sağlayan, tamamen non-invaziv ve hızlı. Benzersiz bir şekilde ciddi bir karşılanmamış ihtiyaca hitap edebilir çünkü Böylece, nefes amonyak ölçüm çekici. Nefes toplama, ancak, benzersiz endişeleri sunuyor. Flebotomi doğal JEO taşır oysaçeşitli öngörülemeyen şekilde hata PARDY (örneğin, turnike zaman, ter kirlenme, kan hücresi hemoliz, laboratuar ölçümü gecikme, vb 5), nefes ölçüm araştırmacılar yeni zorluklar farklı bir grup ile uğraşmak gerekir: değişkenliği nefes, kirlenmeyi ve ağız mukozası ile ya bakteriyel amonyak, ortam havası ve cihaz nem ve sıcaklığın etkisi, vs 6. Gerçekten de, bu bilinmeyen biyoloji keşfetmek için deneysel yöntemler kullanılarak insanlarda deneysel ekipman bağlayan görevi hafife akılsızca. Nedeniyle bu engellere kısmen, nefes amonyak henüz potansiyelini bir araya geldi değil. Bu yazıda, hızlı ve doğru sonuçlar için bizim nefes amonyak ölçüm protokolü sunuyoruz. Monitör, arayüz sampler ve insan etkilerine dikkat: Bizim protokol üç alanda gücü vardır. Monitör, daha önce açıklandığı gibi 7 Rice Üniversitesi&#39;nde meslektaşları tarafından inşa edilmiştir. Mea temelisurement bir kuvars gelişmiş foto akustik spektroskopi bir akustik dönüştürücü olarak bir piezoelektrik diyapazonum istihdam (QEPAS) tekniğidir. Akustik dalgalar hedef izleme gaz türleri tarafından modüle Lazer radyasyonu emme tarafından üretilen zaman foto akustik etki meydana gelir. Izleme gaz ile modüle edilmiş frekans rezonant akustik bir akustik hücre kullanılarak tespit edilir. Amonyak için bir absorpsiyon dalga boyu o nefeste türlerin müdahale spektral müdahalelerden arınmış seçildi. İnsan Solunan nefes ölçüm amaçları için, monitörün ana özellikleri, geniş ölçüm aralığı (50 parça milyar başına ~, en az 5.000 ppb ppb) ve hız (1 sn ölçümleri) içerir. Monitörün hızı nefes döngüsü boyunca zaman çözünürlüğü sağlar. Monitör, özel olarak tasarlanmış bir nefes örnekleyici kuple edilir. Örnekleyici bir basınç sensörü ve kapnograf oluşur. Bu görüntüler ve gerçek zamanlı arşivlerağız basıncı ve karbon dioksit gibi, sensör tarafından belirlenen amonyak konsantrasyonlarının ölçümleri. Bu örneği, bu nedenle, nefes toplanır gibi nefes çaba kalitesini değerlendirmek için teknisyen sağlar. Bu Amerikan Toraks Derneği / Avrupa Solunum Derneği Görev Gücü (ATS / ERS) 8 önerdiği nefes nitrik oksit (NO Fe) analiz için öneriler aşmak için bize sağlar. Her nefes örneği alma için, tek tek yönlü sıralı valf nefes numune ağız noktası kullanıldı. Çünkü örnekleyici tarafından sağlanan monitör ve kalite kontrolleri hızı, dikkatle 9 insan etkilerini değerlendirmeyi başardık. Nefes talimatı deneklerin çoğu, örneğin, başlangıçta hyperventilate. Böyle bir oral pH ve ağız gibi diğer önemli etkiler, örnekleyici, monitör ve tüm ilişkili boru ve nefes modu sıcaklıkları, sonra çalışıldı çalkalanması ve temel fo vardırAşağıda r örnek deneyleri. Son olarak ve belki de en önemlisi, birden çok deneyimli gruplar tamamen farklı sensörler ve ölçüm yöntemleri kullanılarak nefes amonyak ölçüm olduğunu vurgulamak gerekir. Bu önemli avantaj ve geçerliliği olabilir. Tam bir karşılaştırma mevcut çalışma 10,11,12 kapsamı dışındadır.

<table><tbody><tr><td>Rice Ammonia Monitor System</td><td>N/A</td><td>N/A</td><td>Not available for commercial purchase</td></tr><tr><td>Loccioni Breath Sampler</td><td>Loccioni Humancare</td><td>N/A</td><td>Single breath version</td></tr><tr><td>Disposable Mouth Piece</td><td>WestPrime Healthcare</td><td>G011-200</td><td>Manufacturer is AlcoQuant</td></tr><tr><td>Laptop</td><td>Lenovo</td><td>N/A</td><td>Old model no longer sold by manufacturer</td></tr><tr><td>Acid Rinse</td><td>N/A</td><td>N/A</td><td>Household acidic drink (coffee, soft drink, citrus juices, etc)</td></tr><tr><td>Base Rinse</td><td>N/A</td><td>N/A</td><td>Water mixed with a nonexact amount of sodium bicarbonate (Arm &amp;amp; Hammer Baking Soda)</td></tr><tr><td>Neutral Rinse</td><td>N/A</td><td>N/A</td><td>Water</td></tr></tbody></table>

fast and accurate exhaled breath ammonia measurement

This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. 
Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. 
The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

Denekler bazal nefes amonyak seviyeleri geniş bir yelpazede üretmek beklenebilir. Sağlıklı bireyler 100-1.000 ppb bir nefes amonyak ölçümü ile gün başlayabilir. Herhangi bir sıvı ile ağız dışarı durulama hemen saptanabilir nefes amonyak miktarını değiştirir. Nötr ve asidik sıvılar genellikle yarıdan fazla gözlemlenebilir amonyak miktarı kesti. Durulama etkileri kapalı giyer gibi bu seviyeleri daha sonra başlangıca dönün. Suyun etkisi bir asit 2 saat boyunca fazla bir minimum bulgulanabil...

Watch this Scientific Journal Video about Fast and Accurate Exhaled Breath Ammonia Measurement at JoVE.com

Fast and Accurate Exhaled Breath Ammonia Measurement

Ammonia is an important physiologic metabolite relevant to various disease and wellness states. It is also a difficult molecule to measure in breath, which demands particular precautions be taken to obtain accurate results. Not all factors influencing ammonia are known, but progress can be difficult without accounting for these factors.

Hızlı ve Doğru Üfürükle Amonyak Ölçüm

This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that ...

fast-and-accurate-exhaled-breath-ammonia-measurement

Research

JoVE Journal

Medicine

13.2K Görüntüleme.  St. Luke's University Hospital. Ammonia is an important physiologic metabolite relevant to various disease and wellness states. It is also a difficult molecule to measure in breath, which demands particular precautions be taken to obtain accurate results. Not all factors influencing ammonia are known, but progress can be difficult without accounting for these factors.

Video: Fast and Accurate Exhaled Breath Ammonia Measurement

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia

Plasma enhanced chemical vapor deposition (PECVD) of perfluoroalkanes has long been studied for tuning the wetting properties of surfaces. For high surface area microporous materials, such as metal-organic frameworks (MOFs), unique challenges present themselves for PECVD treatments. Herein the protocol for development of a MOF that was previously unstable to humid conditions is presented. The protocol describes the synthesis of Cu-BTC (also known as HKUST-1), the treatment of Cu-BTC with PECVD of perfluoroalkanes, the aging of materials under humid conditions, and the subsequent ammonia microbreakthrough experiments on milligram quantities of microporous materials. Cu-BTC has an extremely high surface area (~1,800 m2/g) when compared to most materials or surfaces that have been previously treated by PECVD methods. Parameters such as chamber pressure and treatment time are extremely important to ensure the perfluoroalkane plasma penetrates to and reacts with the inner MOF surfaces. Furthermore, the protocol for ammonia microbreakthrough experiments set forth here can be utilized for a variety of test gases and microporous materials.

Herein the procedures for plasma enhanced chemical vapor deposition of perfluoroalkanes on microporous materials such as metal-organic frameworks to enhance their stability and hydrophobicity are described. Furthermore, breakthrough testing of milligram quantities of samples is described in detail.

Plazma ile Hidrofobik Metal-Organik Altyapıları hazırlanması Amonyak Kaldırma için perfluorobütanlar Kimyasal Buhar Kaplama Geliştirilmiş

Plasma enhanced chemical vapor deposition (PECVD) of perfluoroalkanes has long been studied for tuning the wetting properties of surfaces. For high ...

Kimya

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Agricultural ammonia (NH3) emissions (90% of total EU emissions) are responsible for about 45% airborne eutrophication, 31% soil acidification and 12% fine dust formation within the EU15. But NH3 emissions also mean a considerable loss of nutrients. Many studies on NH3 emission from organic and mineral fertilizer application have been performed in recent decades. Nevertheless, research related to NH3 emissions after application fertilizers is still limited in particular with respect to relationships to emissions, fertilizer type, site conditions and crop growth. Due to the variable response of crops to treatments, effects can only be validated in experimental designs including field replication for statistical testing. The dominating ammonia loss methods yielding quantitative emissions require large field areas, expensive equipment or current supply, which restricts their application in replicated field trials. This protocol describes a new methodology for the measurement of NH3 emissions on many plots linking a simple semi-quantitative measuring method used in all plots, with a quantitative method by simultaneous measurements using both methods on selected plots. As a semi-quantitative measurement method passive samplers are used. The second method is a dynamic chamber method (Dynamic Tube Method) to obtain a transfer quotient, which converts the semi-quantitative losses of the passive sampler to quantitative losses (kg nitrogen ha-1). The principle underlying this approach is that passive samplers placed in a homogeneous experimental field have the same NH3 absorption behavior under identical environmental conditions. Therefore, a transfer co-efficient obtained from single passive samplers can be used to scale the values of all passive samplers used in the same field trial. The method proved valid under a wide range of experimental conditions and is recommended to be used under conditions with bare soil or small canopies (&#60;0.3 m). Results obtained from experiments with taller plants should be treated more carefully.

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Ammonia emissions are a major threat to the environment by eutrophication, soil acidification and fine particle formation and stem mainly from agricultural sources. This method allows ammonia loss measurements in replicated field trials enabling statistical analysis of emissions and of relationships between crop development and emissions.

Kalibre Pasif Örnekleme - NH Çok arsa Arazi Ölçümleri<sub&gt; 3</subDinamik Tüp Yöntemi ve Pasif Numune bir kombinasyonu ile&gt; Emisyon

Agricultural ammonia (NH3) emissions (90% of total EU emissions) are responsible for about 45% airborne eutrophication, 31% soil acidification and 12% ...

Çevre

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Nitrogen oxides (NOx = NO + NO2) are a family of atmospheric trace gases that have great impact on the environment. NOx concentrations directly influence the oxidizing capacity of the atmosphere through interactions with ozone and hydroxyl radicals. The main sink of NOx is the formation and deposition of nitric acid, a component of acid rain and a bioavailable nutrient. NOx is emitted from a mixture of natural and anthropogenic sources, which vary in space and time. The collocation of multiple sources and the short lifetime of NOx make it challenging to quantitatively constrain the influence of different emission sources and their impacts on the environment. Nitrogen isotopes of NOx have been suggested to vary amongst different sources, representing a potentially powerful tool to understand the sources and transport of NOx. However, previous methods of collecting atmospheric NOx integrate over long (week to month) time spans and are not validated for the efficient collection of NOx in relevant, diverse field conditions. We report on a new, highly efficient field-based system that collects atmospheric NOx for isotope analysis at a time resolution between 30 min and 2 hr. This method collects gaseous NOx in solution as nitrate with 100% efficiency under a variety of conditions. Protocols are presented for collecting air in urban settings under both stationary and mobile conditions. We detail the advantages and limitations of the method and demonstrate its application in the field. Data from several deployments are shown to 1) evaluate field-based collection efficiency by comparisons with in situ NOx concentration measurements, 2) test the stability of stored solutions before processing, 3) quantify in situ reproducibility in a variety of urban settings, and 4) demonstrate the range of N isotopes of NOx detected in ambient urban air and on heavily traveled roadways.

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Previous work suggests that the nitrogen isotopic composition of atmospheric nitrogen oxides might distinguish the influence of different sources in the environment. We report on an automated, mobile, field-based method for the high collection efficiency of atmospheric NOx for N isotopic analysis at an hourly time resolution.

Yüksek çözünürlüklü Mobil Toplama Sistemi NO Azot İzotop Analizi için, Otomatik<sub&gt; X</sub

Nitrogen oxides (NOx = NO + NO2) are a family of atmospheric trace gases that have great impact on the environment. NOx concentrations directly influence ...

Design and Use of a Full Flow Sampling System (FFS) for the Quantification of Methane Emissions

The use of natural gas continues to grow with increased discovery and production of unconventional shale resources. At the same time, the natural gas industry faces continued scrutiny for methane emissions from across the supply chain, due to methane&#39;s relatively high global warming potential (25-84x that of carbon dioxide, according to the Energy Information Administration). Currently, a variety of techniques of varied uncertainties exists to measure or estimate methane emissions from components or facilities. Currently, only one commercial system is available for quantification of component level emissions and recent reports have highlighted its weaknesses.
In order to improve accuracy and increase measurement flexibility, we have designed, developed, and implemented a novel full flow sampling system (FFS) for quantification of methane emissions and greenhouse gases based on transportation emissions measurement principles. The FFS is a modular system that consists of an explosive-proof blower(s), mass airflow sensor(s) (MAF), thermocouple, sample probe, constant volume sampling pump, laser based greenhouse gas sensor, data acquisition device, and analysis software. Dependent upon the blower and hose configuration employed, the current FFS is able to achieve a flow rate ranging from 40 to 1,500 standard cubic feet per minute (SCFM). Utilization of laser-based sensors mitigates interference from higher hydrocarbons (C2+). Co-measurement of water vapor allows for humidity correction. The system is portable, with multiple configurations for a variety of applications ranging from being carried by a person to being mounted in a hand drawn cart, on-road vehicle bed, or from the bed of utility terrain vehicles (UTVs). The FFS is able to quantify methane emission rates with a relative uncertainty of &#177; 4.4%. The FFS has proven, real world operation for the quantification of methane emissions occurring in conventional and remote facilities.

Design and Use of a Full Flow Sampling System FFS for the Quantification of Methane Emissions

We have designed, developed, and implemented a novel full flow sampling system (FFS) for quantification of methane emissions and greenhouse gases from across the natural gas supply chain.

Metan Emisyonları Niceleme Tasarım ve Tam Debi Örnekleme Sistemi (FFS) Kullanımı

The use of natural gas continues to grow with increased discovery and production of unconventional shale resources. At the same time, the natural gas ...

Mühendislik

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry

Exhaled volatile organic compounds (VOCs) have aroused considerable interest, since they can serve as biomarkers for disease diagnosis and environmental exposure in a non-invasive manner. In this work, we present a protocol to characterize the exhaled VOCs in real time by using secondary nanoelectrospray ionization coupled to high resolution mass spectrometry (Sec-nanoESI-HRMS). The homemade Sec-nanoESI source was readily set up based on a commercial nanoESI source. Hundreds of peaks were observed in the background-subtracted mass spectra of exhaled breath, and the mass accuracy values are -4.0-13.5 ppm and -20.3-1.3 ppm in the positive and negative ion detection modes, respectively. The peaks were assigned with accurate elemental composition according to the accurate mass and isotopic pattern. Less than 30 s is used for one exhalation measurement, and it takes approximately 7 min for six replicated measurements.

A protocol for characterizing chemical composition of exhaled breath in real time by using secondary nanoelectrospray ionization coupled to high resolution mass spectrometry is demonstrated.

İkincil Nanoelectrospray iyonlaşma kullanarak gerçek zamanlı nefes analiz için yüksek çözünürlüklü kütle spektrometresi birleştiğinde

Exhaled volatile organic compounds (VOCs) have aroused considerable interest, since they can serve as biomarkers for disease diagnosis and environmental ...

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O

The importance of understanding the fate of nitrate (NO3&#8722;), which is the dominant N species transferred from terrestrial to aquatic ecosystems, has been increasing because global nitrogen loads have dramatically increased following industrialization. Dissimilatory nitrate reduction to ammonium (DNRA) and denitrification are both microbial processes that use NO3&#8722; for respiration. Compared to denitrification, quantitative determinations of the DNRA activity have been carried out only to a limited extent. This has led to an insufficient understanding of the importance of DNRA in NO3&#8722; transformations and the regulating factors of this process. The objective of this paper is to provide a detailed procedure for the measurement of the potential DNRA rate in environmental samples. In brief, the potential DNRA rate can be calculated from the 15N-labeled ammonium (15NH4+) accumulation rate in 15NO3&#8722; added incubation. The determination of the 14NH4+ and 15NH4+ concentrations described in this paper is comprised of the following steps. First, the NH4+ in the sample is extracted and trapped on an acidified glass filter as ammonium salt. Second, the trapped ammonium is eluted and oxidized to NO3&#8722; via persulfate oxidation. Third, the NO3&#8722; is converted to N2O via an N2O reductase deficient denitrifier. Finally, the converted N2O is analyzed using a previously developed quadrupole gas chromatography&#8211;mass spectrometry system. We applied this method to salt marsh sediments and calculated their potential DNRA rates, demonstrating that the proposed procedures allow a simple and more rapid determination compared to previously described methods.

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O

A series of methods to determine the potential DNRA rate based on 14NH4+/15NH4+ analyses is provided in detail. NH4+ is converted into N2O via several steps and analyzed using quadrupole gas chromatography&#8211;mass spectrometry.

14NH4+/15NH4+ Sıralı Dönüşüm Yoluyla N2O'ya Göre Amonyuma Nitrat Azaltma Nın Potansiyel Oranlarının Ölçülmesi

The importance of understanding the fate of nitrate (NO3&#8722;), which is the dominant N species transferred from terrestrial to aquatic ecosystems, has ...

Breath Collection from Children for Disease Biomarker Discovery

Breath collection and analysis can be used to discover volatile biomarkers in a number of infectious and non-infectious diseases, such as malaria, tuberculosis, lung cancer, and liver disease. This protocol describes a reproducible method for sampling breath in children and then stabilizing breath samples for further analysis with gas chromatography-mass spectrometry (GC-MS). The goal of this method is to establish a standardized protocol for the acquisition of breath samples for further chemical analysis, from children aged 4-15 years. First, breath is sampled using a cardboard mouthpiece attached to a 2-way valve, which is connected to a 3 L bag. Breath analytes are then transferred to a thermal desorption tube and stored at 4-5 &#176;C until analysis. This technique has been previously used to capture breath of children with malaria for successful breath biomarker identification. Subsequently, we have successfully applied this technique to additional pediatric cohorts. The advantage of this method is that it requires minimal cooperation on part of the patient (of particular value in pediatric populations), has a short collection period, does not require trained staff, and can be performed with portable equipment in resource-limited field settings.

This protocol describes a simple method for the acquisition of breath samples from children. Briefly, samples of mixed air are pre-concentrated in sorbent tubes prior to gas chromatography-mass spectrometry analysis. Breath biomarkers of infectious and non-infectious diseases can be identified using this breath collection method.

Çocuklar hastalık biyomarker keşif için derlemeden nefes

Breath collection and analysis can be used to discover volatile biomarkers in a number of infectious and non-infectious diseases, such as malaria, ...

Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment of end-tidal CO2 (ETCO2), its accuracy is commonly validated using commercial kits composed of a capnography monitor and its matching disposable nasal cannula sampling lines. The purpose of this study was to assess the compatibility and accuracy of cross-paired capnography sampling lines with a single portable bedside capnography monitor. A series of 4 bench tests were performed to evaluate the tensile strength, rise time, ETCO2 accuracy as a function of respiratory rate, and ETCO2 accuracy in the presence of supplemental O2. Each bench test was performed using specialized, validated equipment to allow for a full evaluation of sampling line performance. The 4 bench tests successfully differentiated between sampling lines from different commercial sources and suggested that due to increased rise time and decreased ETCO2 accuracy, not all nasal cannula sampling lines provide reliable clinical data when cross-paired with a commercial capnography monitor. Care should be taken to ensure that any cross-pairing of capnography monitors and disposable sampling lines is fully validated for use across respiratory rates and supplemental O2 flow rates commonly encountered in clinical settings.

The goal of this study was to evaluate the accuracy of capnography sampling lines used in conjunction with a portable bedside capnography monitor. Sampling lines from 7 manufacturers were evaluated for tensile strength, rise time, and ETCO2 accuracy as a function of respiratory rate or supplemental oxygen flow rate.

Taşınabilir Kapnografi Monitörü ile Kullanıldığında Kapnografi Örnekleme Hattı Uyumluluğunun ve Doğruluğunun Değerlendirilmesi

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment ...

Tıp

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Nitric oxide (NO) activity in vivo is the combined results of its direct effects, the action of its derivatives generated from NO autoxidation, and the effects of nitrosated compounds. Measuring NO metabolites is essential to studying NO activity both at vascular levels and in other tissues, especially in the experimental settings where exogenous NO is administered. Ozone-based chemiluminescence assays allow precise measurements of NO and NO metabolites in both fluids (including plasma, tissue homogenates, cell cultures) and gas mixtures (e.g., exhaled breath). NO reacts with ozone to generate nitrogen dioxide in an excited state. The consequent light emission allows photodetection and the generation of an electric signal reflecting the NO content of the sample. Aliquots from the same sample can be used to measure specific NO metabolites, such as nitrate, nitrite, S-nitrosothiols, and iron-nitrosyl complexes. In addition, NO consumed by cell-free hemoglobin is also quantified with chemiluminescence analysis. An illustration of all these techniques is provided.

Here, we present protocols for detecting nitric oxide and its biologically relevant derivatives using chemiluminescence-based assays with high sensitivity.

Nitrik Oksit ve Türevlerinin Otoksidasyon ve Nitroslu Bileşiklerden Tespiti için Kemilüminesans Bazlı Testler

Nitric oxide (NO) activity in vivo is the combined results of its direct effects, the action of its derivatives generated from NO autoxidation, and the ...

Egzersiz Sırasında Pulmoner Alveolar-Kapiller Rezervin Değerlendirilmesi

Dual Test Gas Pulmonary Diffusing Capacity Measurement During Exercise in Humans Using the Single-Breath Method

The combined single-breath measurement of the diffusing capacity of carbon monoxide (DL,CO) and nitric oxide (DL,NO) is a useful technique to measure pulmonary alveolar-capillary reserve in both healthy and patient populations. The measurement provides an estimate of the participant&#39;s ability to recruit and distend pulmonary capillaries. The method has recently been reported to exhibit a high test-retest reliability in healthy volunteers during exercise of light to moderate intensity. Of note, this technique permits up to 12 repeated maneuvers and only requires a single breath with a relatively short breath-hold time of 5 s. Representative data are provided showing the gradual changes in DL,NO and DL,CO from rest to exercise at increasing intensities&#160;of up to 60% of maximal workload. The measurement of diffusing capacity and evaluation of alveolar-capillary reserve is a useful tool to evaluate the lung&#39;s ability to respond to exercise both in the healthy population as well as in patient populations such as those with chronic lung disease.

Yazar Spotlight: Alveolar-kılcal rezerv ölçümlerinin egzersiz adaptasyonu ve terapötik stratejilere entegre edilmesi

This protocol presents a method to assess pulmonary alveolar-capillary reserve measured by combined single-breath measurement of the diffusing capacity to carbon monoxide (DL,CO) and nitric oxide (DL,NO) during exercise. Assumptions and recommendations for using the technique during exercise form the foundation of this article.

Tek Nefes Yöntemi Kullanılarak İnsanlarda Egzersiz Sırasında İkili Test Gazı Pulmoner Difüzyon Kapasitesi Ölçümü

The combined single-breath measurement of the diffusing capacity of carbon monoxide (DL,CO) and nitric oxide (DL,NO) is a useful technique to measure ...

Hızlı ve Doğru Üfürükle Amonyak Ölçüm

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