Academic literature on the topic 'Reversible losse'
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Journal articles on the topic "Reversible losse"
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Çelik, Kenan, Abdullah Sakin, Savaş Öztürk, Mehmet Yılmaz, Namık Yiğit, Hikmet Feyizoğlu, and Mihriban Gürbüzel. "Çölyak Hastalığında Geçici Sensorinöral İşitme Kaybı: Rastlantısal Bir Bulgu Mu?" Haseki Tıp Bülteni 51, no. 4 (2013): 190–92. http://dx.doi.org/10.4274/haseki.1058.
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Lee, C., P. Robinson, and J. Chelladurai. "Reversible sensorineural hearing loss." International Journal of Pediatric Otorhinolaryngology 66, no. 3 (December 2002): 297–301. http://dx.doi.org/10.1016/s0165-5876(02)00202-1.
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&NA;. "Bone loss with prednisone reversible." Inpharma Weekly &NA;, no. 876 (February 1993): 22. http://dx.doi.org/10.2165/00128413-199308760-00044.
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Ridley, J. K., J. A. Lowe, and H. T. Hewitt. "How reversible is sea ice loss?" Cryosphere Discussions 5, no. 5 (September 8, 2011): 2349–63. http://dx.doi.org/10.5194/tcd-5-2349-2011.
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Abstract. It is well accepted that increasing atmospheric CO2 results in global warming, leading to a decline in polar sea ice area. Here, the specific question of whether there is a tipping point in the sea ice cover is investigated. The global climate model HadCM3, is used to map the trajectory of sea ice area under idealised scenarios. The atmospheric CO2 is first ramped up to four times pre-industrial levels (4 × CO2) then ramped down back to pre-industrial levels. We also examine the impact of stabilising climate at 4 × CO2 prior to ramping CO2 down to pre-industrial levels. Against global mean temperature Arctic sea ice area has little hysteresis while the Antarctic sea ice shows significant hysteresis – its rate of change slower, with falling temperatures, than its rate of change with rising temperatures. However, we show that the driver of the hysteresis is the hemispherical differences in temperature change between transient and stabilisation periods. We find no irreversible behaviour in the sea ice cover.
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Ridley, J. K., J. A. Lowe, and H. T. Hewitt. "How reversible is sea ice loss?" Cryosphere 6, no. 1 (February 13, 2012): 193–98. http://dx.doi.org/10.5194/tc-6-193-2012.
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Abstract. It is well accepted that increasing atmospheric CO2 results in global warming, leading to a decline in polar sea ice area. Here, the specific question of whether there is a tipping point in the sea ice cover is investigated. The global climate model HadCM3 is used to map the trajectory of sea ice area under idealised scenarios. The atmospheric CO2 is first ramped up to four times pre-industrial levels (4 × CO2), then ramped down to pre-industrial levels. We also examine the impact of stabilising climate at 4 × CO2 prior to ramping CO2 down to pre-industrial levels. Against global mean temperature, Arctic sea ice area is reversible, while the Antarctic sea ice shows some asymmetric behaviour – its rate of change slower, with falling temperatures, than its rate of change with rising temperatures. However, we show that the asymmetric behaviour is driven by hemispherical differences in temperature change between transient and stabilisation periods. We find no irreversible behaviour in the sea ice cover.
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Kumar, L., and V. Kochupillai. "Reversible Nail Loss after Cancer Chemotherapy." Acta Oncologica 29, no. 4 (January 1990): 471. http://dx.doi.org/10.3109/02841869009090033.
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Cockey, Carolyn Davis. "Bone Loss From Depo‐Provera Reversible." AWHONN Lifelines 6, no. 6 (December 2002): 491. http://dx.doi.org/10.1111/j.1552-6356.2002.tb00310.x.
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Hood, Linda J., and Douglas B. Webster. "Reversible Conductive Hearing Loss in Mice." Annals of Otology, Rhinology & Laryngology 97, no. 3 (May 1988): 281–85. http://dx.doi.org/10.1177/000348948809700314.
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Fibrin tissue adhesive was injected into the right ears of four 7-week-old CBA/J mice. Auditory brain stem responses (ABRs) were used to monitor changes in auditory sensitivity over the next 26 days, after which the middle ears and cochleas were examined histologically. Mean maximum ABR threshold shifts were as great as 36 dB, and were larger for higher frequencies than for lower. Maximum shifts occurred between 1 and 8 days; by 26 days, thresholds had returned to intensity levels observed before injection.
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Treasure, J. L., G. F. Russell, I. Fogelman, and B. Murby. "Reversible bone loss in anorexia nervosa." BMJ 295, no. 6596 (August 22, 1987): 474–75. http://dx.doi.org/10.1136/bmj.295.6596.474-a.
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Matos, Janini Oliveira, Andréia Migueres Arruda, Shiro Tomita, Patricia de Pinho Marques Araujo, Felipe Barbosa Madeira, and Krishnamurti Matos de Araujo Sarmento Junior. "Cryptococcus Meningitis and reversible hearing loss." Brazilian Journal of Otorhinolaryngology 72, no. 6 (November 2006): 849. http://dx.doi.org/10.1016/s1808-8694(15)31055-7.
Full textDissertations / Theses on the topic "Reversible losse"
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KHAN, BILAL ALAM. "Measurement methods of Gas-Solid Interactions." Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2942142.
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Kos, Cristoffer, and Kristoffer Hermansson. "BUILDING AND SIMULATING DYNAMIC MODELS OF DISTRICT HEATING NETWORKS WITH MODELICA : Using Matlab to process data and automate modelling and simulation." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-36107.
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District heating systems are common in Nordic countries today and accounts for a great portion of the heat demand. In Sweden, total district heating end use in the last years has been around 50 TWh and district heating accounts for roughly 50 % of the total heat demand. Suppliers of district heating must balance demand and supply, often in large and complex networks. Heat propagation can be in the range of hours and it is not known in detail how the heat will propagate during transient conditions. A dynamic model has been developed in OpenModelica and a method for modeling, handling data, simulating and visualizing the results of a district heating network was developed using Matlab as core. Data from Mälarenergi AB, a district heating producer and grid operator, was used for validation of the model. Validation shows that the model works well in predicting heat propagation and temperature distribution in the network and that the model can be scaled up to a large number of heat exchangers and pipes. The model is robust and can handle bi-directional and reversing flows in complex ring structures. It was concluded that OpenModelica together with Matlab is a good combination for creating models of district heating networks, as a high degree of standardization and automation can be achieved. This, together with visualization of the heat propagation, makes it useful for the understanding of the district heating network during transient conditions.Smarta Flöden
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Рєзва, Ксенія Сергіївна. "Удосконалення проточних частин високонапірних оборотних гідромашин на основі чисельного моделювання їх гідродинамічних характеристик." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/40009.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.05.17 – гідравлічні машини і гідропневмоагрегати. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2019 р.
Дисертацію присвячено вирішенню науково-практичної задачі удосконалення проточних частин високонапірних оборотних гідромашин за рахунок розробки методів розрахунку та аналізу їх гідродинамічних характеристик. На підставі розгляду тенденцій розвитку гідроенергетики України, з урахуванням ролі високонапірних оборотних гідромашин в об'єднаній енергетичній системі, відмічено актуальність проектування нових проточних частин. Визначено переваги та недоліки існуючих методів дослідження гідродинамічних процесів у проточних частинах оборотних гідромашин. Наведені результати розрахунку гідродинамічних характеристик елементів проточної частини на основі методу осереднених безрозмірних параметрів для оборотних гідромашин ОРО200-В-100 та ОРО500-В-100. Застосована математична модель робочого процесу гідромашини на основі блочно-ієрархічного підходу для проведення дослідження балансу енергії. Визначено вплив геометричних параметрів елементів проточної частини на показники роботи. Проведено чисельне дослідження просторової течії рідини в проточній частині високонапірних оборотних гідромашин за допомогою CFD, що дозволило визначити та візуалізувати картину течії. Складено баланси енергії гідромашин ОРО200-В-100 та ОРО500-В-100. Відмічено, що розподіл втрат по елементам проточної частини нерівномірний: для ОРО200-В-100 найбільшу частину втрат складають втрати в робочому колесі (близько 56 %), для ОРО500-В-100 – втрати у підводі (близько 62 %). Описано основні положення визначення оптимального режиму роботи оборотної гідромашини. Запропоновано та досліджено модифікований підвід для тихохідної оборотної гідромашини ОРО500-В-100, щоб підвищити її енергетичні показники: краще узгоджені елементи ПЧ та гідравлічний ККД збільшився на 2 %.Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.05.17 – Hydraulic machines and hydropneumatic units. – National Technical University "Kharkiv Polytechnic Institute", 2019. The tеhesis is devoted to the solution of the scientific and practical problem of improvement of the water passages of the high-pressure reversible hydraulic due to calculation and analysis their hydrodynamic characteristics. Based on the review of the trends in the development of hydropower engineering in Ukraine and given the role of high-pressure reversible hydraulic machines in the United Power System, it was noted that the designing a new flow parts is topical task. Advantages and disadvantages of the existing methods for research hydrodynamic processes in water passages of reversible hydraulic machines were identified after their analysis. The results of the calculation of the hydrodynamic characteristics of the elements of the water passages based on the method of averaged dimensionless parameters using the example of reversible hydraulic machines OPO200-B-100 and OPO500-B-100 were demonstrated. The mathematical model of the hydraulic machine working process based on a block-hierarchical approach was used to study the energy balance in the turbine and pump modes of hydraulic machines. The influence of the geometrical parameters of the elements of the water passage on the performance was determined: how the angle of flow in the spiral casing (cп ), the height of the wicket gate (b0 D) and the shape of the wicket gate profile influence the value of the coefficient resistance in the wicket gate. A numerical study of the three-dimensional flow of fluid in the water passage of high-pressure reversible hydraulic machines was carried out using the CFD software. This program allows determining the character of the flow and presenting the fields of distribution of velocity components, pressure and streamlines. The balances of energy were compiled: for the OPO200-B-100 in the turbine and pump operation modes, for the OPO500-B-100 in the turbine operation mode. It is noted that the distribution of losses on the elements of the water passage is not uniform: for the OPO200-B-100, the greatest part of the total losses are losses in the runner (about 56%), for OPO500-B-100 - losses in the inlet (about 62%). The main points for determining the optimal operating mode of the reversible hydraulic machine are described. The modified inlet for low-speed high-pressure hydraulic machine OPO500-B-100 was proposed and investigated to increase energy performance of hydraulic machine. The spiral casing was expanded, the number of stay vane blades and wicket gate blades were reduced to 16. As a result of the calculations of the modified inlet, the obtained results showed that the second variant made it possible to better align the elements of the water passage and the hydraulic efficiency increased by 2 %.
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Рєзва, Ксенія Сергіївна. "Удосконалення проточних частин високонапірних оборотних гідромашин на основі чисельного моделювання їх гідродинамічних характеристик." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/40011.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.05.17 – гідравлічні машини і гідропневмоагрегати. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2019 р.
Дисертацію присвячено вирішенню науково-практичної задачі удосконалення проточних частин високонапірних оборотних гідромашин за рахунок розробки методів розрахунку та аналізу їх гідродинамічних характеристик. На підставі розгляду тенденцій розвитку гідроенергетики України, з урахуванням ролі високонапірних оборотних гідромашин в об'єднаній енергетичній системі, відмічено актуальність проектування нових проточних частин. Визначено переваги та недоліки існуючих методів дослідження гідродинамічних процесів у проточних частинах оборотних гідромашин. Наведені результати розрахунку гідродинамічних характеристик елементів проточної частини на основі методу осереднених безрозмірних параметрів для оборотних гідромашин ОРО200-В-100 та ОРО500-В-100. Застосована математична модель робочого процесу гідромашини на основі блочно-ієрархічного підходу для проведення дослідження балансу енергії. Визначено вплив геометричних параметрів елементів проточної частини на показники роботи. Проведено чисельне дослідження просторової течії рідини в проточній частині високонапірних оборотних гідромашин за допомогою CFD, що дозволило визначити та візуалізувати картину течії. Складено баланси енергії гідромашин ОРО200-В-100 та ОРО500-В-100. Відмічено, що розподіл втрат по елементам проточної частини нерівномірний: для ОРО200-В-100 найбільшу частину втрат складають втрати в робочому колесі (близько 56 %), для ОРО500-В-100 – втрати у підводі (близько 62 %). Описано основні положення визначення оптимального режиму роботи оборотної гідромашини. Запропоновано та досліджено модифікований підвід для тихохідної оборотної гідромашини ОРО500-В-100, щоб підвищити її енергетичні показники: краще узгоджені елементи ПЧ та гідравлічний ККД збільшився на 2 %.Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.05.17 – Hydraulic machines and hydropneumatic units. – National Technical University "Kharkiv Polytechnic Institute", 2019. The tеhesis is devoted to the solution of the scientific and practical problem of improvement of the water passages of the high-pressure reversible hydraulic due to calculation and analysis their hydrodynamic characteristics. Based on the review of the trends in the development of hydropower engineering in Ukraine and given the role of high-pressure reversible hydraulic machines in the United Power System, it was noted that the designing a new flow parts is topical task. Advantages and disadvantages of the existing methods for research hydrodynamic processes in water passages of reversible hydraulic machines were identified after their analysis. The results of the calculation of the hydrodynamic characteristics of the elements of the water passages based on the method of averaged dimensionless parameters using the example of reversible hydraulic machines OPO200-B-100 and OPO500-B-100 were demonstrated. The mathematical model of the hydraulic machine working process based on a block-hierarchical approach was used to study the energy balance in the turbine and pump modes of hydraulic machines. The influence of the geometrical parameters of the elements of the water passage on the performance was determined: how the angle of flow in the spiral casing (cп ), the height of the wicket gate (b0 D) and the shape of the wicket gate profile influence the value of the coefficient resistance in the wicket gate. A numerical study of the three-dimensional flow of fluid in the water passage of high-pressure reversible hydraulic machines was carried out using the CFD software. This program allows determining the character of the flow and presenting the fields of distribution of velocity components, pressure and streamlines. The balances of energy were compiled: for the OPO200-B-100 in the turbine and pump operation modes, for the OPO500-B-100 in the turbine operation mode. It is noted that the distribution of losses on the elements of the water passage is not uniform: for the OPO200-B-100, the greatest part of the total losses are losses in the runner (about 56%), for OPO500-B-100 - losses in the inlet (about 62%). The main points for determining the optimal operating mode of the reversible hydraulic machine are described. The modified inlet for low-speed high-pressure hydraulic machine OPO500-B-100 was proposed and investigated to increase energy performance of hydraulic machine. The spiral casing was expanded, the number of stay vane blades and wicket gate blades were reduced to 16. As a result of the calculations of the modified inlet, the obtained results showed that the second variant made it possible to better align the elements of the water passage and the hydraulic efficiency increased by 2 %.
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Karasad, Mohamed. "Tatouage des images médicales partagées." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0076.
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L'évolution rapide des technologies du multimédia et des communications s'exprime dans le domaine de la santé par la mise à disposition de nouveaux moyens de partage et d'accès distant aux données d'imagerie des patients. Ces moyens prennent désormais une place importante dans la pratique quotidienne médicale. Pour les professionnels de santé, ils facilitent la prise en charge des patients et permettent d'améliorer la gestion de l'information médicale. Dans un tel contexte, la question de la sécurité des données est particulièrement sensible, notamment en termes d'intégrité, d'authenticité et de traçabilité. Aujourd'hui, la plupart des mécanismes de sécurité existants comme les techniques cryptographiques et le contrôle d'accès offre une protection permettent d'empêcher les utilisateurs non-autorisés d'accéder au contenu des données ; des images pour ce qui nous concerne. Cependant, ils n'offrent qu'une protection de type « a priori » dans le sens où l'image est seulement protégée avant que l'accès à son contenu soit donné. Le tatouage numérique a été proposé comme un mécanisme de sécurité complémentaire à ces solutions « a priori ». Il fournit une protection de type « a posteriori » permettant ainsi à l'utilisateur d'accéder au contenu de l'image tout en le maintenant protégée par une « marque » imperceptible. En effet, dans le cas des images, le tatouage modifie ou module les valeurs de niveaux de gris des pixels de celles-ci de manière imperceptible pour coder ou insérer un message (i.e. une marque). Ce message peut être utilisé pour vérifier l'intégrité de l'image, son authenticité ou à des fins de traçabilité. Le tatouage offre ainsi une protection pérenne, indépendante du format de stockage de l'image tatouée. Du fait de la sensibilité des images médicales, l'imperceptibilité est évidemment la contrainte la plus forte à considérer pour le tatouage des images médicales. En effet, la modification des niveaux de gris de l'image peut introduire un doute sur sa validité. C'est dans ce cadre que s'inscrivent les travaux de recherche menés dans cette thèse. Ils visent à développer des nouvelles méthodes de tatouage plus appropriées aux images médicales, c'est-à-dire des méthodes permettant de préserver au mieux la qualité de l'image. Ainsi, nous avons proposé trois solutions originales, qui profitent du bruit d'acquisition inhérent dans les images radiographiques pour y masquer une marque de la même puissance que le bruit. Ainsi, l'image sera protégée et l'information utile pour le diagnostic reste inchangée. La première solution, se base sur des techniques de débruitage pour identifier le bruit dans une image. On parle ici d'identification globale du bruit, par la suite une marque est insérée en respectant la distribution du bruit. La mise à jour de la marque dans cette solution nécessite l'introduction d'une nouvelle distorsion. Pour pallier à cela, nous avons amélioré notre système dans une deuxième solution, pour qu'il devienne réversible, c'est-à-dire à l'extraction de la marque l'image est reconstruite sans pertes de données. Dans la troisième solution, nous nous sommes basés sur une modélisation local du bruit dans les images radiographiques afin d'adapter la marque localement dans l'image. On parle ici du masquage psychovisuel. Ce type de tatouage dès lors était réservé aux images grands public, son utilisation en médicale est une première. Nous avons également mise en place un protocole de validation subjectif en collaboration avec des radiologues afin d'étudier l'impact de tatouage sur la qualité diagnostique des images tatouéesThe rapid evolution of multimedia and communications technologies is emerging in the healthcare field by providing new means of sharing and remote access to patient data. This plays an important role in daily medical practice since it facilitates the care of patients and improves the management of medical information. In this context, the issue of data security is particularly sensitive, in terms of integrity, authenticity and traceability. Nowadays, the most existing security mechanisms, such as cryptographic techniques and access control, provide protection to prevent unauthorized users from accessing data content; images in ours case. However, they offer only an "a priori" protection; which means that the image is only protected before the access to its content is given. Digital watermarking has been proposed as a safety mechanism complementary to these "a priori" solutions. It provides a "posterior" protection, allowing the user to access the content of the image while keeping it protected by an imperceptible "mark". Indeed, in the case of images, the watermark modifies, or modulates, the pixels values in order to encode, or insert, a message (i.e. a mark). This message can be used to check the integrity of the image, its authenticity, or for traceability purposes. Because of the sensitivity of medical images content, imperceptibility is obviously the strongest constraint to consider for watermarking medical images. Indeed, changing the gray levels of the image may introduce a doubt about its validity.The research work carried out in this thesis falls within this context. The objective is to develop new watermarking methods, more appropriate to medical images, which preserve the quality of the image. We have proposed three original solutions, which take advantage of the acquisition noise inherent in radiographic images in order to mask a mark of the same power as the noise. In this manner, the image will be protected and the information, which is useful for the diagnosis, remains unchanged. The first solution aims to globally identify the noise in the image, based on denoising techniques. Afterwards, a mark is inserted, taken in consideration the noise distribution. Updating the mark in this solution may introduce new distortions. To overcome this problem, we have proposed a second solution, which improves our system by making it reversible. Moreover, the mark's extraction will be performed without any loss of data. Our third proposed solution relies on local noise modeling in radiographic images in the purpose of locally adapting the mark in the image. We are referring here to psychovisual masking. This type of watermarking was applied in the case of natural images only. A subjective validation protocol has been performed, in collaboration with radiologists, to study the impact of watermarking on the diagnostic quality of watermarked images
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Tognan, Malik. "Etude de dégradations des performances de Piles à Combustible PEM BT alimentées en H2/O2 lors de campagnes d'endurance : du suivi de l'état de santé en opération à la modélisation du vieillissement." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0047/document.
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Les travaux développés dans cette thèse traitent de la thématique du vieillissement des Piles à Combustible (PàC) à Membranes Echangeuses de Protons Basse Température (PEM BT). L’utilisation d’une PàC dans un contexte stationnaire à l’intérieur d’une batterie H2 (tandem PàC/Electrolyseur avec un étage de stockage H2 voire O2) est envisagée dans le cadre du déploiement d’un micro-réseau insulaire basé sur des sources d’énergie renouvelables (éolien et photovoltaïque). Deux aspects connexes associés à l’utilisation de la PàC et à son vieillissement dans cet environnement sont investigués dans ce travail de thèse : d’une part la manière dont les performances de la PàC et son rendement vont se dégrader au cours du temps et d’autre part les méthodes et outils qui vont être utilisés pour évaluer son état de santé durant sa période d’activité. La première de ces deux thématiques est abordée via l’étude d’une base de données d’essais en endurance à courant constant effectués sur des prototypes de stack PEM BT fonctionnant en H2/O2. L’hétérogénéité du vieillissement pour les différents stacks testés est mise en avant, de même que le découplage entre les pertes d’étanchéité interne et les dégradations des performances en tension au courant nominal durant les différentes campagnes. Une méthodologie proposant une dissociation des dynamiques réversibles et irréversibles de décroissance de la tension de la PàC au cours du temps est ensuite exposée et sert de base à la construction d’un modèle de dégradation de la tension sur un fonctionnement à courant fixe. Le modèle montre des résultats encourageants et une perspective liée à son utilisation dans le cadre du pronostic est suggérée. La question de la sensibilité du vieillissement aux variations dynamiques de la charge est ensuite abordée de manière complémentaire à ces essais d’endurance (effectués à charge constante) via une campagne de vieillissement effectuée sur des monocellules hybridées ou non directement par des supercondensateurs et cyclant sur un profil de courant dynamique. Une comparaison des évolutions des performances des monocellules au cours du temps dans les deux cas (hybridé et non-hybridé) est effectuée et met en avant l’effet du cyclage dynamique sur la dégradation des performances des PàC. La deuxième thématique touchant les méthodes et outils dédiés à l’évaluation de l’état de santé de la PàC durant son fonctionnement est introduite dans la suite de ces travaux en se penchant notamment sur une des causes majeures de la fin de vie des PàC : l’accroissement du crossover d’H2 vers l’O2 lié à la perte d’étanchéité interne de la membrane. Des mesures de tension à vide (OCV) effectuées lors de phases d’arrêt/démarrage sont scrutées a posteriori pour une des campagnes de la base de données d’essais en endurance. L’objectif est de rechercher des éventuelles corrélations entre l’accroissement des fuites internes et l’évolution de ces mesures au cours du temps afin de développer des potentiels indicateurs des fuites internes. Une séquence opératoire de mise en gaz mettant en avant un lien entre le niveau de crossover d’H2 et la vitesse d’effondrement de l’OCV pour certaines cellules du stack est identifiée et reproduite à l’occasion d’une campagne complémentaire d’essais. Une dernière partie du manuscrit est finalement consacrée à une approche théorique prospective dédiée à l’intégration d’un phénomène parasite, l’oxydation du Pt, dans la modélisation des performances statiques et dynamiques d’une PàC. Les retombées attendues portent sur l’amélioration de l’interprétation des caractérisations menées régulièrement (EIS, OCV, balayages sinus de forte amplitude aux très basses fréquences…), permettant le suivi du vieillissementThis thesis work deals with the thematic of the Low Temperature Proton Exchange Membrane (PEM LT) Fuel Cell (FC) aging. The use of a FC inside a H2 battery (association of a FC, an electrolyzer and H2 / O2 tanks) in a stationary context is considered in an island micro-grid based on renewable energies (wind and solar power). Two axes linked with the FC use and aging in this context are investigated in this work: one of the axes is centered in the study of the FC performance decrease dynamics over time and the other on the development of methods and tools dedicated to the state of health monitoring during the FC operation. The first thematic is introduced through the exploitation of several aging campaigns performed on PEM FC stack prototypes under constant current solicitations. The stacks considered are fed with pure O2 on the cathode side. A focus is made on the aging heterogeneity inside the stacks and a decoupling between the nominal voltage degradation dynamics and the development of the H2 internal leak with time is highlighted for the different stacks and campaigns. A generic methodology dissociating the reversible and the irreversible voltage losses dynamics is proposed and is further used as a basis to model the nominal voltage degradation with time. The model built in this way is showing encouraging results and its potential use for prognostic purpose is suggested. Whereas these investigations focus on the FC performance degradations under constant current solicitation, the impact of load current dynamic variations on the FC aging is also treated with an experimental study performed on single cells. An ageing campaign under a dynamic load profile is performed on several single cells directly hybridized or not by supercapacitors. The hybridized cells are cycling on an almost-constant current profile whereas the non-hybridized cells are cycling on a dynamic one. A comparison of the performances evolution with time in both cases (hybridized and nothybridized) is done and highlights the effect of the dynamic cycling on the FC performance degradation. The second thematic dealing with the FC state of health evaluation is introduced with one of the main causes of the FC end-of-life: the development of the H2 internal leak between the anode and cathode compartments. Open Circuit Voltage (OCV) measurements performed during start-up and shut-down routines phases are scanned a posteriori in one of the aging campaign of the database. The objective is to seek some potential correlations between those OCV measurements and the H2 internal leak increase over time in order to develop internal leak indicators. A gases introduction operating sequence highlighting a link between the internal leak level and the OCV drift for some stack’s cells is identified during some start-up phases and reproduced during a complementary campaign. A last part of the manuscript is finally dedicated to the integration of a parasitic mechanism (the Pt oxidation) into the FC theoretical quasi-static and dynamic performance modeling. The model integrating this phenomenon is showing some abilities to explain and analyze several experimental features observed on classical performance characterization measurements (EIS, OCV measurements, large amplitude sinus sweep at very low frequency…), opening some perspectives for the FC state of health monitoring
Books on the topic "Reversible losse"
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Year of reversible loss. Berkeley, CA: El Leon Literary Arts/Andrea Young Arts, 2012.
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Kra, Siegfried J. Aging myths: Reversible causes of mind and memory loss. New York: McGraw-Hill, 1986.
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Kra, Siegfried J. Aging myths: Reversible causes of mind and memory loss. New York: McGraw-Hill, 1986.
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Abrahim, Mohammed. Reversible: ABRAHIM MD PROTOCOL for Sustained Weight Loss and Reversal of Chronic Diseases. Independently Published, 2020.
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Ariana, Morteza. Type 2 Diabetes Is Reversible: Lose Weight and Heal Type 2 Diabetes by Intermittent Fasting. Independently Published, 2020.
Find full textBook chapters on the topic "Reversible losse"
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Przelaskowski, Artur. "Lifting-Based Reversible Transforms for Lossy-to-Lossless Wavelet Codecs." In Computer Analysis of Images and Patterns, 61–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/3-540-44692-3_8.
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Wu, Jiaji, Lei Wang, Yong Fang, and L. C. Jiao. "Multiplierless Reversible Integer TDLT/KLT for Lossy-to-Lossless Hyperspectral Image Compression." In Satellite Data Compression, 185–213. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-1183-3_9.
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"of sensory hearing loss seem to be reversible. For." In Hearing Loss, 225–26. CRC Press, 2005. http://dx.doi.org/10.1201/b21609-38.
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Naskar, Ruchira, Rajat Subhra Chakraborty, Dev Kumar Das, and Chandan Chakraborty. "Digital Image Watermarking." In Research Developments in Computer Vision and Image Processing, 195–207. IGI Global, 2014. http://dx.doi.org/10.4018/978-1-4666-4558-5.ch011.
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With the advent of telemedicine, Digital Rights Management of medical images has become a critical issue pertaining to security and privacy preservation in the medical industry. The technology of telemedicine makes patient diagnosis possible for physicians located at a remote site. This technology involves electronic transmission of medical images over the internet, thus raising the need for ensuring security and privacy of such information. Digital watermarking is a widely used technique for the authentication and protection of multimedia data such as images and video against various security and privacy threats. But such digital rights management practices as watermarking often lead to considerable distortion or information loss of the medical images. The medical images being highly sensitive and legally valuable assets of the medical industry, such information loss are often not tolerable. Most importantly, such information loss may lead to incorrect patient diagnosis or reduced accuracy of disease detection. In this chapter we investigate the impact of digital watermarking, and its effect on the accuracy of disease diagnosis, specifically diagnosis of malarial infection caused by Plasmodium vivax parasite. We have used a computer–aided, automatic diagnostic model for our work in this chapter. Our experimental results show that although general (lossy) digital watermarking reduces the diagnostic accuracy, it can be improved with the use of reversible (lossless) watermarking. In fact, the adverse effect(s) of watermarking on the diagnostic accuracy can be completely mitigated through the use of reversible watermarking.
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Samec, Pavel, Aleš Kučera, and Gabriela Tomášová. "Soil Degradation Processes Linked to Long-Term Forest-Type Damage." In Sustainable Development. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.106390.
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Forest degradation impairs ability of the whole landscape adaptation to environmental change. The impacts of forest degradation on landscape are caused by a self-organization decline. At the present time, the self-organization decline was largely due to nitrogen deposition and deforestation which exacerbated impacts of climate change. Nevertheless, forest degradation processes are either reversible or irreversible. Irreversible forest degradation begins with soil damage. In this paper, we present processes of forest soil degradation in relation to vulnerability of regulation adaptability on global environmental change. The regulatory forest capabilities were indicated through soil organic matter sequestration dynamics. We devided the degradation processes into quantitative and qualitative damages of physical or chemical soil properties. Quantitative soil degradation includes irreversible loss of an earth’s body after claim, erosion or desertification, while qualitative degradation consists of predominantly reversible consequences after soil disintegration, leaching, acidification, salinization and intoxication. As a result of deforestation, the forest soil vulnerability is spreading through quantitative degradation replacing hitherto predominantly qualitative changes under continuous vegetation cover. Increasing needs to natural resources using and accompanying waste pollution destroy soil self-organization through biodiversity loss, simplification in functional links among living forms and substance losses from ecosystem. We concluded that subsequent irreversible changes in ecosystem self-organization cause a change of biome potential natural vegetation and the land usability decrease.
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Roy, Subhrajit Sinha, Abhishek Basu, and Avik Chattopadhyay. "Hardware Implementation of a Visual Image Watermarking Scheme Using Qubit/Quantum Computation Through Reversible Methodology." In Research Anthology on Advancements in Quantum Technology, 127–63. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8593-1.ch006.
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In this chapter, hardware implementation of an LSB replacement-based digital image watermarking algorithm is introduced. The proposed scheme is developed in spatial domain. In this watermarking process, data or watermark is implanted into the cover image pixels through an adaptive last significant bit (LSB) replacement technique. The real-time execution of the watermarking logic is developed here using reversible logic. Utilization of reversible logic reduces the power dissipation by means of no information loss. The lesser power dissipation enables a faster operation as well as holds up Moore's law. The experimental results confirm that the proposed scheme offers high imperceptibility with a justified robustness.
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Roy, Subhrajit Sinha, Abhishek Basu, and Avik Chattopadhyay. "Hardware Implementation of a Visual Image Watermarking Scheme Using Qubit/Quantum Computation Through Reversible Methodology." In Quantum-Inspired Intelligent Systems for Multimedia Data Analysis, 95–140. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-5219-2.ch004.
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In this chapter, hardware implementation of an LSB replacement-based digital image watermarking algorithm is introduced. The proposed scheme is developed in spatial domain. In this watermarking process, data or watermark is implanted into the cover image pixels through an adaptive last significant bit (LSB) replacement technique. The real-time execution of the watermarking logic is developed here using reversible logic. Utilization of reversible logic reduces the power dissipation by means of no information loss. The lesser power dissipation enables a faster operation as well as holds up Moore's law. The experimental results confirm that the proposed scheme offers high imperceptibility with a justified robustness.
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McKinstry-Wu, Andrew, and Max B. Kelz. "Neural Mechanisms of Anaesthetics." In Oxford Textbook of Neuroscience and Anaesthesiology, edited by George A. Mashour and Kristin Engelhard, 3–16. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780198746645.003.0001.
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For more than 170 years since their discovery, the mechanisms by which general anaesthetics act on the central nervous system (CNS) to produce their signature triad of reversible unconsciousness, amnesia, and immobility have remained incompletely understood. Recently, numerous studies have begun to illuminate mechanisms of anaesthetic hypnosis at molecular, neuronal, and neural-network levels. Despite these advances, an integrated understanding of anaesthetic hypnosis across organizational levels remains elusive. Nevertheless, multiple relevant anaesthetic molecular targets have been identified along with subcortical and cortical centres involved in entering and exiting the anaesthetic state. On the network scale, recent studies suggest cortical network properties that change at the moment of loss of consciousness are not merely indicative of that loss, but possibly the cause of it. Taken together, these actions on the CNS from receptor to network modulation offer a tantalizing if incomplete picture of how general anaesthetics act to produce reversible unconsciousness.
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Nikolov, S., J. Vera, and O. Wolkenhauer. "Bifurcation Analysis of a Model Accounting for the 14-3-3s Signalling Compartmentalisation." In Quality Assurance in Healthcare Service Delivery, Nursing and Personalized Medicine, 61–70. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-61350-120-7.ch004.
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Bifurcation theory studies the qualitative changes in the phase portrait when we vary the parameters of the system. In this book chapter we adapt and extend a mathematical model accounting for the subcellular localisation of 14-3-3s, a protein involved in cell cycle arrest and the regulation of apoptosis. The model is analysed with analytical tools coming from Lyapunov-Andronov theory, and our analytical calculations predict that soft (reversible) loss of stability takes place.
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Cvitkovic, Katarina, Anita Pusic Sesar, Antonio Sesar, and Ivan Cavar. "Ophthalmic Disorders in Posterior Reversible Encephalopathy Syndrome Associated with Preeclampsia." In Preeclampsia. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.101270.
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Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological entity presented with different symptoms such as visual disturbances, headaches, seizures, severe hypertension and altered mental status. It has been recognized in a different pathological conditions, although preeclampsia/eclampsia is the most common cause of PRES. The pathogenesis of PRES is still not fully understood, but it seems that failure of cerebrovascular autoregulation causing vasogenic edema, cerebral vasoconstriction, and disruption of the blood brain barrier plays an important role. Cortical blindness, hypertensive retinopathy, serous retinal detachment (SRD), central retinal artery and vein occlusions, retinal or vitreous hemorrhages, anterior ischemic optic neuropathy (AION) and Purtscher’s retinopathy are ophthalmic disorders that may occur in PRES associated with preeclampsia. Among these, cortical blindness is the best documented complication of preeclampsia. Magnet resonance imaging (MRI) is a gold standard to establish the diagnosis of PRES because clinical findings are not sufficiently specific. Typically, there are bilateral cortical occipital lesions with hyperdensity on T2-weighted MRI. Blindness due to occipital lesions is reversible and the vision loss is usually regained within 4 h to 8 days.
Conference papers on the topic "Reversible losse"
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Bartz, Wilfried J. "Evaluation of Reversible and Irreversible Viscosity Losses Using the Viscosity Loss Trapezoid*." In International Fuels & Lubricants Meeting & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1994. http://dx.doi.org/10.4271/941980.
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Himes, R. E., S. A. Ali, M. A. Hardy, M. D. Holtmyer, and J. D. Weaver. "Reversible, Crosslinkable Polymer for Fluid-Loss Control." In SPE Formation Damage Control Symposium. Society of Petroleum Engineers, 1994. http://dx.doi.org/10.2118/27373-ms.
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Andrawis, Alfred, Barun Ranjitkar, XingZhong Yan, and Yuelin Peng. "Reversible low-loss fiber optic hydrazine sensor." In SPIE Defense, Security, and Sensing, edited by Tuan Vo-Dinh, Robert A. Lieberman, and Günter Gauglitz. SPIE, 2010. http://dx.doi.org/10.1117/12.861426.
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Chen, Heng, Geert Braeckman, Adrian Munteanu, and Peter Schelkens. "Reversible DCT-based lossy-to-lossless still image compression." In 2013 20th IEEE International Conference on Image Processing (ICIP). IEEE, 2013. http://dx.doi.org/10.1109/icip.2013.6738336.
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Harling, Mitchell, Varun Kelkar, Chukwuemeka Okoro, Mbaye Diouf, Ayman F. Abouraddy, and Kimani C. Toussaint. "A Reversible Optical-coherence Converter." In Frontiers in Optics. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/fio.2022.jw4a.7.
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We demonstrate here that entropy, or random fluctuations, in an optical degree of freedom (DoF) can be reversibly swapped between different DoFs, such that coherence is converted back and forth between them without loss of energy.
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Lei Wang, Jiaji Wu, Licheng Jiao, Li Zhang, and Guangming Shi. "Lossy to lossless image compression based on reversible integer DCT." In 2008 15th IEEE International Conference on Image Processing - ICIP 2008. IEEE, 2008. http://dx.doi.org/10.1109/icip.2008.4711935.
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Redondo-Iglesias, Eduardo, Pascal Venet, and Serge Pelissier. "Measuring Reversible and Irreversible Capacity Losses on Lithium-Ion Batteries." In 2016 IEEE Vehicle Power and Propulsion Conference (VPPC). IEEE, 2016. http://dx.doi.org/10.1109/vppc.2016.7791723.
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Gelman, Vitaly. "Energy Savings With Reversible Thyristor Controlled Rectifier." In 2009 Joint Rail Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/jrc2009-63013.
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The paper deals with energy savings in Traction Systems available with Thyristor Controlled Rectifiers (TCR) and Reversible TCR (RTCR). TCR provides active voltage control, RTCR in addition has power recuperation into AC line. The energy balance of the TCR and diode rectifier systems are calculated, including losses in the rails, car’s power train and friction losses. The TCR advantages over diode rectifiers: better voltage regulation and fault current limiting allow us to reduce the number of substations and increase their service life. Major energy savings are through recuperation back to AC line using RTCR, with additional savings through increased DC bus voltage. The estimated energy savings depending on the system parameters, train speed profile, etc. can be as high as 50%.
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Lyall, M. Eric, Paul I. King, and Rolf Sondergaard. "Endwall Loss and Mixing Analysis of a High Lift Low Pressure Turbine Cascade." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68709.
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A high lift LPT profile designated L2A is used as a test bed for studying the origin of endwall mixing loss and the role of vortical structures in loss development. It is shown analytically and experimentally that the mixing forces within the endwall wake can be decoupled into either mean flow or turbulent forces, and can be further classified as either reversible or irreversible. Among the irreversible forces, mean flow shear is negligible compared to turbulent shear, suggesting that turbulence dissipation is the dominant cause of loss generation. As a result, the mean flow components of the vortical structures do not generate significant mixing losses. Rather than mixing effects, the mean flow of the vortices cause the suction surface boundary layer to separate inside the passage, thereby generating the large low energy regions typical of endwall flows. Losses are generated as the low energy regions mix out. This vortex separation effect is demonstrated with an experiment using a profile fence and pressure surface modification near the endwall. The findings in this paper suggest that profile modifications near the endwall that suppress suction surface separation may provide loss reductions additive to those that weaken vortical structures, such as endwall contouring.
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Winkler, Wolfgang G., and Mark C. Williams. "Reversible Process Structures as a Base of Sustainable Engineering." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65407.
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The analysis of exergy losses of a system is a well-known way to determine the influence of the second law on existing systems. Thermo-economics combines this methodology with economic calculations. Using this methodology engineering becomes an evolutionary process. Since system structures are virtual, reversible system structures are possible and inevitable irreversibility is only caused by its real components. They can be described by their exergetic efficiency. Thus reversible system structures can be used as general valid benchmarks for system engineering. It allows easy comparison or a trade-off between possible solutions. The use of a few basic reversible processes allows the building of larger reversible structures including an effective management of released and demanded entropy within the system, as can be shown in different applications and missions. The effective use of renewable sources can be considered as well however bioprocesses are not investigated yet.
Reports on the topic "Reversible losse"
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Kamma, Dr Prudhvi Srujan, and Dr Aishwarya Badugu. AN UNUSUAL PRESENTATION OF EXTRAPULMONARY TUBERCULOSIS AS FEVER WITH PANCYTOPENIA: A CASE REPORT. World Wide Journals, February 2023. http://dx.doi.org/10.36106/ijar/5105754.
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Background: In the developing countries, tuberculosis is a signicant health issue. The vague presentation causes extrapulmonary tuberculosis to take longer to be diagnosed. Pancytopenia is one of the haematological symptoms of extrapulmonary tuberculosis. Pancytopenia may result from hypersplenism, maturation arrest, hemophagocytic lymphohistiocytosis, or inltration of the bone marrow by caseating or noncaseating granulomas causing reversible or irreversible brosis. We Case presentation: report a case of a 70 year-old man who presented with pyrexia of unknown origin with signicant loss of weight and loss of appetite. He had pallor with mild hepatosplenomegaly. He had high inammatory markers with pancytopenia in a peripheral blood smear. His chest radiograph was normal, and he had a negative Mantoux. The common risk factors such as diabetes, human immunodeciency virus (HIV) infection, chronic kidney disease, malnutrition, and immunosuppressant therapy which might contribute him to be vulnerable to TB, were not found. The denite diagnosis of disseminated tuberculosis was made on the basis of caseating tuberculous granulomas in the bone marrow. Due to its Conclusions: ambiguous and nonspecic presentation, widespread TB continues to be difcult to diagnose. Particularly in places where tuberculosis is endemic, the possibility of disseminated tuberculosis should be taken into account in cases of pyrexia of unknown origin with peripheral cytopenia. In such cases, it is crucial to perform a bone marrow culture and histopathological examination simultaneously because ndings of routine diagnostics like chest radiography or Mantoux tests may be negative.
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Akalu, Mulugeta, Misganaw Gashaw, and Zerihun Asegid. The Tax Response to COVID-19 in Ethiopia: Lessons for the Future. Institute of Development Studies, January 2023. http://dx.doi.org/10.19088/ictd.2023.002.
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The government of Ethiopia, like other governments, has provided tax response measures in order to mitigate the socio-economic impacts of COVID-19. These measures, among others, include a waiver of outstanding tax liabilities that taxpayers owe to the government; a tax amnesty or relief on interest and penalties for tax debt; and an extension of filing and tax payment deadlines. These tax measures were adopted with the purposes of helping affected businesses, to keep employees at work, to stimulate the economy and to reduce COVID-19 infections. To be effective, tax relief measures should have been targeted, temporary, speedy, abuse resistant, cost recoverable, predictable, reversible, scalable, easy to administer, resilient to health measures, and adapted to the specific needs of Ethiopia. The strong sides of the Ethiopian tax responses are their speedy nature and the fact that they consider the revenue space and address the status of the poor. The challenges observed on the design and enforcement of the tax measures include lack of adequate targeting, lack of prior assessment, administrative uneasiness, lack of records on the revenue loss, absence of monitoring and evaluation, and that they unfairly benefitted those who failed to comply with their tax duties. Prior assessment, targeted support, convenient response administration, coordination among the government organs, the need for the tax responses to be free from discrimination, the need for appropriate data recording, fair dispute settlement procedures and the need for a permanent disaster response department are suggested for similar incidents in the future.
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Husson, Scott M., Viatcheslav Freger, and Moshe Herzberg. Antimicrobial and fouling-resistant membranes for treatment of agricultural and municipal wastewater. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598151.bard.
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This research project introduced a novel membrane coating strategy to combat biofouling, which is a major problem for the membrane-based treatment of agricultural and municipal wastewaters. The novelty of the strategy is that the membrane coatings have the unique ability to switch reversibly between passive (antifouling) and active (antimicrobial) fouling control mechanisms. This dual-mode approach differs fundamentally from other coating strategies that rely solely on one mode of fouling control. The research project had two complementary objectives: (1) preparation, characterization, and testing of dual-mode polymer nanolayers on planar surfaces and (2) evaluation of these nanolayers as membrane modifiers. The first objective was designed to provide a fundamental understanding of how polymer nanolayer chemistry and structure affect bacterial deposition and to demonstrate the reversibility of chemical switching. The second objective, which focused on membrane development, characterization, and testing, was designed to demonstrate methods for the production of water treatment membranes that couple passive and active biofouling control mechanisms. Both objectives were attained through synergistic collaboration among the three research groups. Using planar silicon and glass surfaces, we demonstrated using infrared spectroscopy that this new polymer coating can switch reversibly between the anti-fouling, zwitterion mode and an anti-microbial, quaternary amine mode. We showed that switching could be done more than 50 times without loss of activity and that the kinetics for switching from a low fouling zwitterion surface to an antimicrobial quaternary amine surface is practical for use. While a low pH was required for switching in the original polymer, we illustrated that by slightly altering the chemistry, it is possible to adjust the pH at which the switching occurs. A method was developed for applying the new zwitterionic surface chemistry onto polyethersulfone (PES) ultrafiltration membranes. Bacteria deposition studies showed that the new chemistry performed better than other common anti-fouling chemistries. Biofilm studies showed that PESultrafiltration membranes coated with the new chemistry accumulated half the biomass volume as unmodified membranes. Biofilm studies also showed that PES membranes coated with the new chemistry in the anti-microbial mode attained higher biofilm mortality than PES membranes coated with a common, non-switchablezwitterionic polymer. Results from our research are expected to improve membrane performance for the purification of wastewaters prior to use in irrigation. Since reduction in flux due to biofouling is one of the largest costs associated with membrane processes in water treatment, using dual-mode nanolayer coatings that switch between passive and active control of biofouling and enable detachment of attached biofoulants would have significant economic and societal impacts. Specifically, this research program developed and tested advanced ultrafiltration membranes for the treatment of wastewaters. Such membranes could find use in membrane bioreactors treating municipal wastewater, a slightly upgraded version of what presently is used in Israel for irrigation. They also may find use for pretreatment of agricultural wastewaters, e.g., rendering facility wastewater, prior to reverse osmosis for desalination. The need to desalinate such impaired waters water for unlimited agricultural use is likely in the near future.
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Chamovitz, A. Daniel, and Georg Jander. Genetic and biochemical analysis of glucosinolate breakdown: The effects of indole-3-carbinol on plant physiology and development. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597917.bard.
Full textAbstract:
Genetic and biochemical analysis of glucosinolate breakdown: The effects of indole-3-carbinol on plant physiology and development Glucosinolates are a class of defense-related secondary metabolites found in all crucifers, including important oilseed and vegetable crops in the Brassica genus and the well-studied model plant Arabidopsis thaliana. Upon tissue damage, such as that provided by insect feeding, glucosinolates are subjected to catalysis and spontaneous degradation to form a variety of breakdown products. These breakdown products typically have a deterrent effect on generalist herbivores. Glucosinolate breakdown products also contribute to the anti-carcinogenic effects of eating cabbage, broccoli and related cruciferous vegetables. Indole-3-carbinol, a breakdown product of indol-3-ylmethylglucosinolate, forms conjugates with several other plant metabolites. Although some indole-3-carbinol conjugates have known functions in defense against herbivores and pathogens, most play as yet unidentified roles in plant metabolism, and possibly also plant development. At the outset, our proposal had three main hypotheses: (1) There is a specific detoxification pathway for indole-3-carbinol; (2) Metabolites derived from indole-3-carbinol are phloem-mobile and serve as signaling molecules; and (3) Indole-3-carbinol affects plant cell cycle and cell-differentiation pathways. The experiments were designed to enable us to elucidate how indole-3-carbinol and related metabolites affect plants and their interactions with herbivorous insects. We discovered that indole-3- carbinol rapidly and reversibly inhibits root elongation in a dose-dependent manner, and that this inhibition is accompanied by a loss of auxin activity in the root meristem. A direct interaction between indole-3-carbinol and the auxin perception machinery was suggested, as application of indole-3-carbinol rescued auxin-induced root phenotypes. In vitro and yeast-based protein interaction studies showed that indole-3-carbinol perturbs the auxin-dependent interaction of TIR1 with Aux/IAA proteins, supporting the notion that indole-3-carbinol acts as an auxin antagonist. Furthermore, transcript profiling experiments revealed the influence of indole-3-carbinol on auxin signaling in root tips, and indole-3-carbinol also affected auxin transporters. Brief treatment with indole-3-carbinol led to a reduction in the amount of PIN1 and to mislocalization of PIN2. The results indicate that chemicals induced by herbivory, such as indole-3-carbinol, function not only to repel herbivores, but also as signaling molecules that directly compete with auxin to fine tune plant growth and development, which implies transport of indole-3- carbinol that we are as yet unsuccessful in detecting. Our results indicate that plant defensive metabolites also have secondary functions in regulating aspects of plant metabolism, thereby providing diversity in defense-related plant signaling pathways. Such diversity of of signaling by defensive metabolites would be beneficial for the plant, as herbivores and pathogens would be less likely to mount effective countermeasures. We propose that growth arrest can be mediated directly by the herbivory-induced chemicals, in our case, indole-3-carbinol. Thus, glucosinolate breakdown to I3C following herbivory would have two outcomes: (1) Indole-3-carbinaol would inhibit the herbivore, while (2) at the same time inducing growth arrest within the plant. Thus, our results indicate that I3C is a defensive phytohormone that modulates auxin signaling, leading to growth arrest.