Relevant bibliographies by topics / PHOG

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Academic literature on the topic 'PHOG'

Author: Grafiati
Published: 4 June 2021
Last updated: 11 September 2023

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Journal articles on the topic "PHOG"

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Imantoko, Imantoko, Arief Hermawan, and Donny Avianto. "Comparative analysis of support vector machine and k-nearest neighbors with a pyramidal histogram of the gradient for sign language detection." Matrix : Jurnal Manajemen Teknologi dan Informatika 11, no. 2 (July 15, 2021): 107–18. http://dx.doi.org/10.31940/matrix.v11i2.2433.

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The communication method using sign language is very efficient considering that the speed of information delivery is closer to verbal communication (speaking) compared to writing or typing. Because of this, sign language is often used by people who are deaf, speech impaired, and normal people to communicate. To make sign language translation easier, a system is needed to translate symbols formed from hand movements (in the form of images) into text or sound. This study aims to compare performance such as accuracy and computation time of Support Vector Machine (SVM) and K-Nearest Neighbors (KNN) with Pyramidal Histogram of Gradient (PHOG) for feature extraction, to know which one is better at recognizing sign language. Yield, both combined methods PHOG-SVM and PHOG-KNN can recognize images from hand movements that form certain symbols. The system built using the SVM classification produces the highest accuracy of 82% at PHOG level 3, while the system built with the KNN classification produces the highest accuracy of 78% at PHOG level 2. The total computation time of the fastest training and testing by the SVM model is 236.53 seconds at PHOG level 3, while the KNN model is 78.27 seconds at PHOG level 3. In terms of accuracy, PHOG-SVM is better, but in terms of computation time, PHOG-KNN takes the place.
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Spencer, John. "Blowing away the PHOG." Clinical Teacher 4, no. 1 (February 23, 2007): 1. http://dx.doi.org/10.1111/j.1743-498x.2007.00146.x.

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Ghorbel, Sofiane, Jan Kormanec, Alexandra Artus, and Marie-Joelle Virolle. "Transcriptional Studies and Regulatory Interactions between the phoR-phoP Operon and the phoU, mtpA, and ppk Genes of Streptomyces lividans TK24." Journal of Bacteriology 188, no. 2 (January 15, 2006): 677–86. http://dx.doi.org/10.1128/jb.188.2.677-686.2006.

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ABSTRACT The PhoR/PhoP two-component system of Streptomyces lividans was previously shown to allow the growth of the bacteria at low Pi concentrations and to negatively control antibiotic production. The present study focuses on the transcriptional analysis of phoR and phoP, along with the phoU and mtpA genes that are transcribed divergently from the phoRP operon in S. lividans. The effect of phoR, phoP, phoU, and ppk mutations on transcription of these genes was examined under phosphate-replete and phosphate-limited conditions. We demonstrated that phoR and phoP were cotranscribed as a leaderless bicistronic transcript cleaved at discrete sites toward the 3′ end of phoR. In addition, phoP could also be transcribed alone from a promoter located at the 3′ end of phoR. The phoU and mtpA genes, predicted to encode metal binding proteins, were shown to be transcribed as monocistronic transcripts. The expression of phoR-phoP, phoP, and phoU was found to be induced under conditions of Pi limitation in S. lividans TK24. This induction, requiring both PhoR and PhoP, was significantly weaker in the phoU mutant but much stronger in the ppk mutant than in the parental strain. The expression of mtpA was also shown to be up-regulated when Pi was limiting but independently of PhoR/PhoP. The induction of mtpA expression was much stronger in the phoU mutant strain than in the other strains. This study revealed interesting regulatory interactions between the different genes and allowed us to propose putative roles for PhoU and MtpA in the adaptation to phosphate scarcity.
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Antelmann, Haike, Christian Scharf, and Michael Hecker. "Phosphate Starvation-Inducible Proteins ofBacillus subtilis: Proteomics and Transcriptional Analysis." Journal of Bacteriology 182, no. 16 (August 15, 2000): 4478–90. http://dx.doi.org/10.1128/jb.182.16.4478-4490.2000.

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ABSTRACT The phosphate starvation response in Bacillus subtiliswas analyzed using two-dimensional (2D) polyacrylamide gel electrophoresis of cell extracts and supernatants from phosphate-starved cells. Most of the phosphate starvation-induced proteins are under the control of ςB, the activity of which is increased by energy depletion. In order to define the proteins belonging to the Pho regulon, which is regulated by the two-component regulatory proteins PhoP and PhoR, the 2D protein pattern of the wild type was compared with those of a sigB mutant and aphoR mutant. By matrix-assisted laser desorption ionization–time of flight mass spectrometry, two alkaline phosphatases (APases) (PhoA and PhoB), an APase-alkaline phosphodiesterase (PhoD), a glycerophosphoryl diester phosphodiesterase (GlpQ), and the lipoprotein YdhF were identified as very strongly induced PhoPR-dependent proteins secreted into the extracellular medium. In the cytoplasmic fraction, PstB1, PstB2, and TuaD were identified as already known PhoPR-dependent proteins, in addition to PhoB, PhoD, and the previously described PstS. Transcriptional studies of glpQ and ydhFconfirmed the strong PhoPR dependence. Northern hybridization and primer extension experiments showed that glpQ is transcribed monocistronically from a ςA promoter which is overlapped by four putative TT(A/T)ACA-like PhoP binding sites. Furthermore, ydhF might be cotranscribed withphoB initiating from the phoB promoter. Only a small group of proteins remained phosphate starvation inducible in bothphoR and sigB mutant and did not form a unique regulation group. Among these, YfhM and YjbC were controlled by ςB-dependent and unknown PhoPR-independent mechanisms. Furthermore, YtxH and YvyD seemed to be induced after phosphate starvation in the wild type in a ςB-dependent manner and in the sigB mutant probably via ςH. YxiE was induced by phosphate starvation independently of ςB and PhoPR.
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Vogel, K., W. Hörz, and A. Hinnen. "The two positively acting regulatory proteins PHO2 and PHO4 physically interact with PHO5 upstream activation regions." Molecular and Cellular Biology 9, no. 5 (May 1989): 2050–57. http://dx.doi.org/10.1128/mcb.9.5.2050-2057.1989.

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The repressible acid phosphatase gene PHO5 of Saccharomyces cerevisiae requires the two positively acting regulatory proteins PHO2 and PHO4 for expression. pho2 or pho4 mutants are not able to derepress the PHO5 gene under low-Pi conditions. Here we show that both PHO2 and PHO4 bind specifically to the PHO5 promoter in vitro. Gel retardation assays using promoter deletions revealed two regions involved in PHO4 binding. Further characterization by DNase I footprinting showed two protected areas, one located at -347 to -373 (relative to the ATG initiator codon) (UASp1) and the other located at -239 to -262 (UASp2). Exonuclease III footprint experiments revealed stops at -349 and -368 (UASp1) as well as at -245 and -260 (UASp2). Gel retardation assays with the PHO2 protein revealed a binding region that lay between the two PHO4-binding sites. DNase I footprint analysis suggested a PHO2-binding site covering the region between -277 and -296.
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Vogel, K., W. Hörz, and A. Hinnen. "The two positively acting regulatory proteins PHO2 and PHO4 physically interact with PHO5 upstream activation regions." Molecular and Cellular Biology 9, no. 5 (May 1989): 2050–57. http://dx.doi.org/10.1128/mcb.9.5.2050.

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The repressible acid phosphatase gene PHO5 of Saccharomyces cerevisiae requires the two positively acting regulatory proteins PHO2 and PHO4 for expression. pho2 or pho4 mutants are not able to derepress the PHO5 gene under low-Pi conditions. Here we show that both PHO2 and PHO4 bind specifically to the PHO5 promoter in vitro. Gel retardation assays using promoter deletions revealed two regions involved in PHO4 binding. Further characterization by DNase I footprinting showed two protected areas, one located at -347 to -373 (relative to the ATG initiator codon) (UASp1) and the other located at -239 to -262 (UASp2). Exonuclease III footprint experiments revealed stops at -349 and -368 (UASp1) as well as at -245 and -260 (UASp2). Gel retardation assays with the PHO2 protein revealed a binding region that lay between the two PHO4-binding sites. DNase I footprint analysis suggested a PHO2-binding site covering the region between -277 and -296.
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Adkins, Melissa W., Stephanie K. Williams, Jeffrey Linger, and Jessica K. Tyler. "Chromatin Disassembly from the PHO5 Promoter Is Essential for the Recruitment of the General Transcription Machinery and Coactivators." Molecular and Cellular Biology 27, no. 18 (July 9, 2007): 6372–82. http://dx.doi.org/10.1128/mcb.00981-07.

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ABSTRACT The disassembly of promoter nucleosomes appears to be a general property of highly transcribed eukaryotic genes. We have previously shown that the disassembly of chromatin from the promoters of the Saccharomyces cerevisiae PHO5 and PHO8 genes, mediated by the histone chaperone anti-silencing function 1 (Asf1), is essential for transcriptional activation upon phosphate depletion. This mechanism of transcriptional regulation is shared with the ADY2 and ADH2 genes upon glucose removal. Promoter chromatin disassembly by Asf1 is required for recruitment of TBP and RNA polymerase II, but not the Pho4 and Pho2 activators. Furthermore, accumulation of SWI/SNF and SAGA at the PHO5 promoter requires promoter chromatin disassembly. By contrast, the requirement for SWI/SNF and SAGA to facilitate Pho4 activator recruitment to the nucleosome-buried binding site in the PHO5 promoter occurs prior to chromatin disassembly and is distinct from the stable recruitment of SWI/SNF and SAGA that occurs after chromatin disassembly.
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Mutia, Cut, Fitri Arnia, and Rusdha Muharar. "Improving the Performance of CBIR on Islamic Women Apparels Using Normalized PHOG." Bulletin of Electrical Engineering and Informatics 6, no. 3 (September 1, 2017): 271–80. http://dx.doi.org/10.11591/eei.v6i3.657.

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The designs of Islamic women apparels is dynamically changing, which can be shown by emerging of online shops selling clothing with fast updates of newest models. Traditionally, buying the clothes online can be done by querying the keywords to the retrieval system. The approach has a drawback that the keywords cannot describe the clothes designs precisely. Therefore, a searching based on content–known as content-based image retrieval (CBIR)–is required. One of the features used in CBIR is the shape. This article presents a new normalization approach to the Pyramid Histogram of Oriented Gradients (PHOG) as a mean for shape feature extraction of women Islamic clothing in a retrieval system. We refer to the proposed approach as normalized PHOG (NPHOG). The Euclidean distance measured the similarity of the clothing. The performance of the system was evaluated by using 340 clothing images, comprised of four clothing categories, 85 images for each category: blouse-pants, long dress, outerwear, and tunic. The recall and precision parameters measured the retrieval performance; the Histogram of Oriented Gradients (HOG) and PHOG were the methods for comparison. The experiments showed that NPHOG improved the HOG and PHOG performance in three clothing categories.
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Mutia, Cut, and Muhammad Akmal. "Content Based Image Retrieval Busana Muslimah Menggunakan Fitur Kombinasi PHOG dan DCD." Jurnal Teknologi Informasi 5, no. 1 (June 29, 2021): 70–76. http://dx.doi.org/10.36294/jurti.v5i1.2021.

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Abstract - The development of Muslim clothing has increased significantly, especially in Indonesia, where the majority of the population is Muslim. Designers have appeared with a variety of fashion styles that attract consumers, especially young consumers. Technological developments have also influenced the way designers promote and sell their work by utilizing online commerce. So that consumers can search and find various models and colors of clothing that interest them. In this study, the search for Muslim clothing was carried out using the visual content of images or also known as features. The features used in this study are a combination of color and shape features, because shape and color are an attraction for consumers in choosing clothes. Search using image content as a query is known as CBIR. This study applies the PHOG as a shape feature extraction method and the DCD for the extraction of color features. The dataset used is 180 images of Muslim clothing. The performance of CBIR Muslim clothing using a combination of PHOG and DCD features is measured with recall, precision, and f-measure parameters. The results of the performance measurement show that the combination of PHOG and DCD features is better applied to blouse pants clothing. The highest scores were obtained from the red clothing group of 68% (P), 22.2%, and 33.3% (F). Then followed by a group of robes, and outerwear. Keywords - CBIR, PHOG, DCD, Feature and Clothing. Abstrak - Busana muslimah memiliki bentuk dan warna yang beragam dan menarik minat konsumen, banyak situs belanja online yang mempromosikan dan menjual produknya. Namun, pencarian busana muslimah pada situs tersebut masih menggunakan teks, sehingga hasil pencarian produknya sering tidak sesuai dengan harapan konsumen.Pada penelitian ini, pencarian busana muslimah dilakukan dengan menggunakan isi visual citra atau disebut juga sebagai fitur, adapun fitur yang digunakan adalah kombinasi fitur warna dan bentuk, karena bentuk (model) dan warna merupakakan daya tarik bagi konsumen dalam memilih busana. Pencarian menggunakan isi gambar sebagai query dikenal dengan Content Based Image Retrieval (CBIR). Penelitian ini menerapkan Pyramid Histogram of Oriented Gradient (PHOG) sebagai metode ekstraksi fitur bentuk dan Dominant Color Descriptor (DCD) untuk ekstraksi fitur warna. Dataset yang digunakan ada 180 citra busana muslimah, terdiri dari 60 citra blus celana, 60 gamis, dan 60 outerwear. Kemiripan query dengan dataset dilakukan dengan menghitung jarak Euclidean. Pengukuran Kinerja CBIR busana muslimah menggunakan kombinasi fitur PHOG dan DCD dilakukan dengan menghitung nilai recall, precision, dan f-measure. Hasil pengukuran kinerja menunjukkan bahwa kombinasi fitur PHOG dan DCD lebih baik diterapkan pada busana blus-celana. Berdasarkan pengukuruan kinerja dengan precision (P), recall (R0, dan f-measure (F). Nilai tertinggi diperoleh dari kelompok busana berwarna merah sebesar 68 % (P), 22.2%, dan 33.3 % (F). Kemudian diikuti dengan kelompok busana gamis, dan outerwear. Kata Kunci - CBIR, PHOG, DCD, Fitur dan Busana.
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Haldimann, Andreas, Larry L. Daniels, and Barry L. Wanner. "Use of New Methods for Construction of Tightly Regulated Arabinose and Rhamnose Promoter Fusions in Studies of theEscherichia coli Phosphate Regulon." Journal of Bacteriology 180, no. 5 (March 1, 1998): 1277–86. http://dx.doi.org/10.1128/jb.180.5.1277-1286.1998.

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ABSTRACT Escherichia coli genes regulated by environmental inorganic phosphate (Pi) levels form the phosphate (Pho) regulon. This regulation requires seven proteins, whose synthesis is under autogenous control, including response regulator PhoB, its partner, histidine sensor kinase PhoR, all four components of the Pi-specific transport (Pst) system (PstA, PstB, PstC, and PstS), and a protein of unknown function called PhoU. Here we examined the effects of uncoupling PhoB synthesis and PhoR synthesis from their normal controls by placing each under the tight control of the arabinose-regulated ParaB promoter or the rhamnose-regulated PrhaB promoter. To do this, we made allele replacement plasmids that may be generally useful for construction of ParaB orPrhaB fusions and for recombination of them onto the E. coli chromosome at the araCBAD orrhaRSBAD locus, respectively. Using strains carrying such single-copy fusions, we showed that a PrhaB fusion is more tightly regulated than a ParaB fusion in that a PrhaB-phoR + fusion but not a ParaB-phoR + fusion shows a null phenotype in the absence of its specific inducer. Yet in the absence of induction, bothParaB-phoB + andPrhaB-phoB + fusions exhibit a null phenotype. These data indicate that less PhoR than PhoB is required for transcriptional activation of the Pho regulon, which is consistent with their respective modes of action. We also used these fusions to study PhoU. Previously, we had constructed strains with precise ΔphoU mutations. However, we unexpectedly found that such ΔphoU mutants have a severe growth defect (P. M. Steed and B. L. Wanner, J. Bacteriol. 175:6797–6809, 1993). They also readily give rise to compensatory mutants with lesions inphoB, phoR, or a pst gene, making their study particularly difficult. Here we found that, by usingParaB-phoB +,PrhaB-phoB +, orPrhaB-phoR + fusions, we were able to overcome the extremely deleterious growth defect of a Pst+ ΔphoU mutant. The growth defect is apparently a consequence of high-level Pst synthesis resulting from autogenous control of PhoB and PhoR synthesis in the absence of PhoU.
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Dissertations / Theses on the topic "PHOG"

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Vasconcelos, Fernanda Nogales da Costa. "Caracterização dos genes phoA1, phoA2, phoB, phoU e PstS, membros do regulon PHO de Chromobacterium violaceum." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-24092014-161707/.

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Chromobacterium violaceum é uma bactéria de vida livre, móvel, que habita fontes de água e solos pobres de regiões tropicais e subtropicais. Nestes habitats, em que a concentração de fosfato é baixa, o regulon PHO encontra-se ativado. No laboratório, esta bactéria é capaz de crescer razoavelmente bem, apesar da limitação de fosfato, atingindo um rendimento celular similar ao observado na abundância deste nutriente. Mutações nos genes pstS, phoU, phoA1 e phoA2 foram construídas. As mutações pstS e phoU não causaram qualquer alteração no padrão de expressão da fosfatase alcalina, sugerindo que estes genes não participam da repressão dos genes de PHO. Porém, o mutante pstS mostrou-se deficiente na captação de Pi. Os mutantes phoA1 e phoA2 apresentaram, cada um, severa redução na atividade da fosfatase alcalina. Foi investigada a possibilidade de PhoA1 e PhoA2 formarem uma proteína heterodimérica. Fusões transcricionais entre phoU e phoB ao gene lacZ, revelaram que estes genes respondem à carência de Pi. Surpreendentemente, C. violaceum se mostrou pouco resistente a estresses ambientais.
Chromobacterium violaceum is a free-living, mobile bacterium that inhabits water sources and soils of tropical and subtropical regions, where the phosphate concentration is low. The PHO regulon is activated in response to low phosphate concentration in the environment. Surprisingly, the growth yield of C. violaceum under phosphate excess or under phosphate limitation is very similar. Mutations in pstS, phoU, phoA1 and phoA2 genes were constructed. The expression of alklaine phosphatase was not affected by the phoU and pstS mutations, suggesting that these genes do not participate in the repression of the PHO regulon. However, the pstS mutant was deficient in the uptake of Pi. The phoA1 and phoA2 mutants presented each one a severe reduction in alkaline phosphatase activity. The hypothesis that PhoA1 and PhoA2 form a heterodimeric protein was investigated. Transcriptional fusions between the promoters of phoB and phoU to lacZ showed that these genes respond to Pi starvation. Stress resistance assays showed that C. violaceum is generally sensitive to environmental stresses.
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Loney, Erica. "PhoR, PhoP and MshC: Three essential proteins of Mycobacterium tuberculosis." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1396606314.

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Le, Sage Valerie. "Ligand sensing and signal trasnduction by the two-component system PhoP/PhoQ." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95624.

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The Citrobacter rodentium genome sequence contains a phoPQ operonhomologous (~79% identity) to that of S. typhimurium. We report that C. rodentiumPhoQ senses fluctuations in Mg2+ concentrations and acidic pH. Surprisingly, PhoQwas not activated by the presence of AMPs. However, activation by AMPs is observedwhen C. rodentium PhoP/PhoQ was expressed in as. typhimurium background. Weidentified an outer membrane protease of the omptin family that was responsible forinhibiting PhoQ activation by AMPs. In stark contrast to S. typhimurium, which relieson LPS modifications to resist AMPs, our results suggest that C. rodentium promotesresistance through a PhoP/PhoQ-dependent OM protease to inhibit disruption of theouter membrane by AMPs .
La séquence du génome de Citrobacter rodentium présente un opéron phoPQ(~79% identité) homologue à celui de S. typhimurium. Nous avons déterminé quePhoQ de C. rodentium perçoit les variations de pH et en Mg2+ du milieu environnant.De manière surprenante, les PAMs ne causent aucune augmentation d'activité dePhoQ. Néeanmoins, lorsque le système PhoP/PhoQ de C. rodentium est exprimé chezS. typhimurium les PAMs activent PhoQ. Nous avons identifié une protéine de lamembrane externe appartenant à la famille des omptin qui est responsable del'inactivité de PhoQ en présence des P AMs. Ces résultats suggèrent que le mécanismede résistance aux PAMs de C. rodentium serait régulé par le système PhoP/PhoQ et une protéase qui empêcherait la destruction de la membrane externe par les P AMs. Cemécanisme de défense est différent de celui du système PhoP/PhoQ de S. typhimuriumqui repose essentiellement sur des modification du LPS .
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Salazar, Michael E. Jr (Michael Edward). "Induction kinetics of the PhoQ-PhoP two-component system in Escherichia coli." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104179.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Cells rely on signal transduction systems to sense and respond to changes in their enviroments. When a stimulus is present, the corresponding signal transduction system will activate and enact the appropriate biological response, often by modulating target gene expression. In many cases, the temporal dynamics of the activation of target gene expression in the presence of constant stimulus is complex, and often exhibits one or several pulses. How these complex temporal dynamics are regulated at the molecular level is unknown for many signal transduction systems. In this thesis, I discuss the molecular regulation of the temporal dynamics of PhoQ-PhoP induction in Escherichia coli. The PhoQ-PhoP pathway is a canonical two-component system that responds to low extracellular Mg'+, certain antimicrobial peptides, and potentially other unknown factors. Upon activation, the bifunctional histidine kinase PhoQ autophosphorylates and subsequently phosphotransfers to the response regulator PhoP, thereby activating it to increase transcription of PhoP target genes. Because PhoQ is bifunctional, PhoQ acts as a phosphatase on phosphorylated PhoP in the absence of stimulus, thereby keeping the system inactivated. When the PhoQ-PhoP system is strongly induced, PhoP target genes exhibit impulse kinetics, meaning gene expression increases to a maximal level and subsequently decreases to an eventual steady state. We discovered that this impulse response is caused by a negative feedback loop in which active PhoP transcribes mgrB, a gene encoding a small membrane protein that interacts directly with PhoQ to repress the output of the system. MgrB selectively inhibits the ability of PhoQ to phosphorylate PhoP, and permits PhoQ to act as a phosphatase on phosphorylated PhoP. This change in PhoQ activity causes a decrease in the level of active PhoP and the level of PhoP target genes. This thesis reveals how negative feedback loops and histidine kinase bifunctionality can drive the kinetics of two-component system induction in bacteria, and more generally explores how cells regulate changes in gene expression over time.
by Michael E. Salazar, Jr.
Ph. D.
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Khan, Rizwan Ahmed. "Détection des émotions à partir de vidéos dans un environnement non contrôlé." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10227/document.

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Dans notre communication quotidienne avec les autres, nous avons autant de considération pour l’interlocuteur lui-même que pour l’information transmise. En permanence coexistent en effet deux modes de transmission : le verbal et le non-verbal. Sur ce dernier thème intervient principalement l’expression faciale avec laquelle l’interlocuteur peut révéler d’autres émotions et intentions. Habituellement, un processus de reconnaissance d’émotions faciales repose sur 3 étapes : le suivi du visage, l’extraction de caractéristiques puis la classification de l’expression faciale. Pour obtenir un processus robuste apte à fournir des résultats fiables et exploitables, il est primordial d’extraire des caractéristiques avec de forts pouvoirs discriminants (selon les zones du visage concernées). Les avancées récentes de l’état de l’art ont conduit aujourd’hui à diverses approches souvent bridées par des temps de traitement trop couteux compte-tenu de l’extraction de descripteurs sur le visage complet ou sur des heuristiques mathématiques et/ou géométriques.En fait, aucune réponse bio-inspirée n’exploite la perception humaine dans cette tâche qu’elle opère pourtant régulièrement. Au cours de ces travaux de thèse, la base de notre approche fut ainsi de singer le modèle visuel pour focaliser le calcul de nos descripteurs sur les seules régions du visage essentielles pour la reconnaissance d’émotions. Cette approche nous a permis de concevoir un processus plus naturel basé sur ces seules régions émergentes au regard de la perception humaine. Ce manuscrit présente les différentes méthodologies bio-inspirées mises en place pour aboutir à des résultats qui améliorent généralement l’état de l’art sur les bases de référence. Ensuite, compte-tenu du fait qu’elles se focalisent sur les seules parties émergentes du visage, elles améliorent les temps de calcul et la complexité des algorithmes mis en jeu conduisant à une utilisation possible pour des applications temps réel
Communication in any form i.e. verbal or non-verbal is vital to complete various daily routine tasks and plays a significant role inlife. Facial expression is the most effective form of non-verbal communication and it provides a clue about emotional state, mindset and intention. Generally automatic facial expression recognition framework consists of three step: face tracking, feature extraction and expression classification. In order to built robust facial expression recognition framework that is capable of producing reliable results, it is necessary to extract features (from the appropriate facial regions) that have strong discriminative abilities. Recently different methods for automatic facial expression recognition have been proposed, but invariably they all are computationally expensive and spend computational time on whole face image or divides the facial image based on some mathematical or geometrical heuristic for features extraction. None of them take inspiration from the human visual system in completing the same task. In this research thesis we took inspiration from the human visual system in order to find from where (facial region) to extract features. We argue that the task of expression analysis and recognition could be done in more conducive manner, if only some regions are selected for further processing (i.e.salient regions) as it happens in human visual system. In this research thesis we have proposed different frameworks for automatic recognition of expressions, all getting inspiration from the human vision. Every subsequently proposed addresses the shortcomings of the previously proposed framework. Our proposed frameworks in general, achieve results that exceeds state-of-the-artmethods for expression recognition. Secondly, they are computationally efficient and simple as they process only perceptually salient region(s) of face for feature extraction. By processing only perceptually salient region(s) of the face, reduction in feature vector dimensionality and reduction in computational time for feature extraction is achieved. Thus making them suitable for real-time applications
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Gardner, Stewart G. "Studies of PhoU in Escherichia coli: Metal Binding, Dimerization,Protein/Protein Interactions, and a Signaling Complex Model." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/5685.

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Phosphate is an essential nutrient for all forms of life. Escherichia coli has a PhoR/PhoB two component regulatory system that controls the expression of various genes whose products allow the cell to thrive in low phosphate environments. The signaling mechanism of the PhoR/PhoB system has been studied and the phosphorylation cascade that controls gene expression is well understood. What is still unknown is how PhoR senses the phosphate level of the environment. The PstS, PstC, PstA, PstB, and PhoU proteins play a role in this signal sensing. This work confirms the hypothesis that the PstSCAB complex senses the environmental phosphate and that phosphate signal is passed through PhoU to PhoR. Further, this work characterizes residues important for interaction on PhoU and PhoR and identifies a structural model for interaction. This model points to a potential mechanism for PhoU mediated signaling to PhoR. We tested this model with direct coupling analysis and obtained further confirmation. Further use of these techniques may elucidate more of the interactions necessary for proper phosphate signaling.
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Politis, Panagiotis K. "The role of chromatin in the regulation of PHO5 and PHO3 genes in Saccharomyces cerevisiae." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343632.

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Münsterkötter, Martin. "Kooperative Wechselwirkungen von Transkriptionsfaktoren und Histonen mit Promotorelementen der Phosphatasegene PHO5 und PHO8 in Saccharomyces cerevisiae." Diss., lmu, 2001. http://nbn-resolving.de/urn:nbn:de:bvb:19-853.

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Gellatly, Shaan Lae. "Regulation of the PhoP-PhoQ two-component system in Pseudomonas aeruginosa and its role in virulence." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42991.

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Pseudomonas aeruginosa is an opportunistic bacterial pathogen that can cause severe infections in individuals with underlying medical conditions. P. aeruginosa primarily infects at epithelial surfaces where it interacts initially via type IV pili, flagella and LPS. Two component regulatory systems control many aspects of pseudomonal physiology and mediate adaptation to environmental changes including those that occur in the host. This thesis outlines the contributions of these systems to the cytotoxicity to epithelial cells and sheds light on the regulation mediated by the two-component sensor PhoQ. Systems that contributed to cytotoxicity fell into several themes including motility, cyclic-di-GMP regulation, and carbon and nitrogen utilization. Several genes controlled by PhoQ were shown to be dysregulated during infection of lung epithelial cells, including upregulation of oprH-phoP-phoQ, the lipid A modification gene arnB, and downregulation of a lipid A deacylase, pagL. Consistent with this, lipid A from a phoQ mutant grown in varying magnesium concentrations displayed alterations. LPS of the phoQ mutant revealed increased inflammatory properties as demonstrated by increased secretion of the cytokines IL6, TNFalpha , and IL10 from PBMCs. The decrease in cytotoxicity of a phoQ mutant correlated with a decrease in secretion of lipases and proteases when co-incubated with cultured epithelial cells. These results suggest that the PhoP-PhoQ system might adapt the bacterium to lung epithelia and that this might contribute to and be exacerbated by the selective pressure of inhaled polymyxin therapeutics. Unlike most sensor kinases that phosphorylate their cognate response regulators, PhoQ of P. aeruginosa appears to act only as a phosphatase of its cognate regulator PhoP. Here it was demonstrated that PhoP was not activated by PhoQ in a luminescence reporter screen. The sensor kinase, RoxS, involved in regulation of the cyanide insensitive oxidase, was revealed as a candidate phosphodonor to PhoP. Since mutation of roxS was able to reduce but not eliminate expression from the oprH-phoP-phoQ operon, it is conceivable that other sensors contribute to PhoP phosphorylation. It was also demonstrated that PhoP contributed to the known polymyxin resistance of a phoQ mutant but only partially to cytotoxicity. These results emphasize the complexity of the PhoP-PhoQ regulatory system.
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Rodrigues, Alves Lucas Bocchini. "Patogenicidade de Salmonella Gallinarum com deleção dos genes phoP e phoQ (SG∆phoPQ) em aves comerciais." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152283.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
RESUMO – Salmonella Gallinarum (SG) é um patógeno hospedeiro-específico que causa o tifo aviário, doença sistêmica severa que é considerada uma das principais preocupações da indústria avícola mundial. Quando infecta a ave, SG utiliza mecanismos de evasão para sobreviver e replicar no interior de macrófagos. Nesse contexto, os genes phoPQ codificam o sistema regulatório de dois componentes (PhoPQ) que regula genes de virulência responsáveis pela adaptação de Salmonella spp. a fatores antimicrobianos como baixo pH, peptídeos antimicrobianos e baixas concentrações de cátions bivalentes. No presente estudo, objetivou-se investigar a função desses genes para SG. Assim, uma estirpe de SG com genes phoPQ defectivos (SG ∆phoPQ) foi construída e sua patogenicidade avaliada em aves poedeiras de 20 dias de vida susceptíveis ao tifo aviário. SG ∆phoPQ não causou sinais clínicos nem mortalidade em aves desafiadas oralmente, sendo não-patogênica. Ademais, essa estirpe não foi recuperada de fígados e baços. Por outro lado, aves desafiadas subcutaneamente com a estirpe mutante tiveram alterações patológicas discretas a moderadas e baixas contagens bacterianas em tecidos de fígado e baço. A partir dos dados, observa-se que SG ∆phoPQ é atenuado para aves o que sugere que ambos os genes são importantes durante a infecção sistêmica em aves por SG.
ABSTRACT – Salmonella Gallinarum (SG) is a host-restrict pathogen that causes fowl typhoid, a severe systemic disease that is one of the major concerns to the poultry industry worldwide. When infecting the bird, SG makes use of evasion mechanisms to survive and to replicate within macrophages. In this context, phoPQ genes encode a two-component regulatory system (PhoPQ) that regulates virulence genes responsible for adaptation of Salmonella spp. to antimicrobial factors such as low pH, antimicrobial peptides and deprivation of bivalent cations. Herein, we aimed to investigate the role of the mentioned genes to SG. Thus, a phoPQ-depleted SG strain (SG ∆phoPQ) was constructed and its virulence assessed in twenty-day-old laying hens susceptible to fowl typhoid. SG ∆phoPQ did cause neither clinical signs nor mortality in birds orally challenged, being non-pathogenic. Furthermore, this strain was not recovered from livers or spleens. On the other hand, chickens challenged subcutaneously with the mutant strain had discreet to moderate pathological changes and also low bacterial counts in liver and spleen tissues. These findings show that SG ∆phoPQ is attenuated to susceptible chickens and suggest that both genes are important during chicken systemic infection by SG.
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Books on the topic "PHOG"

1

Phog. Multān: Kitāb Nagar, 2007.

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Kerkhoff, Blair. Phog Allen: The father of basketball coaching. Indianapolis, IN: Masters Press, 1996.

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Satthāman, Sǣngdāo. Phon phong nām. Chīang Mai: Sathāban Khrư̄akhāi Kānrīanrū Chumchon, 2003.

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Santiwong, Thongchai. Phon Trī Čhamlong thī phom rūčhak. Kō̜thō̜mō̜. [i.e. Krung Thēp Mahā Nakhō̜n]: Dūang Kamon, 1992.

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Suputtikō, Montrī. Pratchayā hǣng Wat Phō =: Philosophy of Wat Pho. Krung Thēp: Samnakphim Khlet Thai, 2008.

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Sīwisutthiwong, Phra, ed. Bōt Wat Phō =: The ubosot of Wat Pho. 2nd ed. Krung Thēp: ʻAmmarin Phrinting ʻǣn Phaplitching, 2001.

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Chumphengphan, Prathum, Sitthā Phinitphūwadon, ʻAmnāt Bunsiriwibūn, Kō̜rakot Phō̜nwisitsakun, and Wat Phrachētuphon (Bangkok Thailand), eds. Tukkatā silā Čhīn Wat Phō =: The Chinese stone figurines of Wat Pho. [Bangkok: Wat Phrachētuphon], 2005.

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Lu, The. Le phong phong vien. Houston, Texas: Zieleks, 1990.

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Geerken, Hartmut. Phos. Herrsching: Waitawhile, 2005.

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Panyānuwat, ʻAnurak. Kānpramœ̄n phon Khrōngkān Phatthanā Chapho̜ Phư̄nthī, ʻAmphœ̄ Phop Phra (Phō̜. Phō̜. Phō̜.), Phō̜. Sō̜. 2530-2534. Tāk: Khrōngkān Phatthanā Chapho̜ Phư̄nthī, 1991.

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Book chapters on the topic "PHOG"

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Sinha, Atreyee, Sugata Banerji, and Chengjun Liu. "Novel Gabor-PHOG Features for Object and Scene Image Classification." In Lecture Notes in Computer Science, 584–92. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-34166-3_64.

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Dahbali, M., Noureddine Aboutabit, and N. Lamghari. "Arabic Handwritten Characters Recognition by Combining PHOG Descriptor with Ensemble Methods." In Lecture Notes in Networks and Systems, 141–53. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-29313-9_13.

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Ghanim, Taraggy M., Mahmoud I. Khalil, and Hazem M. Abbas. "PHoG Features and Kullback-Leibler Divergence Based Ranking Method for Handwriting Recognition." In Artificial Neural Networks in Pattern Recognition, 293–305. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-99978-4_23.

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Redies, Christoph, Seyed Ali Amirshahi, Michael Koch, and Joachim Denzler. "PHOG-Derived Aesthetic Measures Applied to Color Photographs of Artworks, Natural Scenes and Objects." In Computer Vision – ECCV 2012. Workshops and Demonstrations, 522–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-33863-2_54.

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Miller, Samuel I. "PhoP/PhoQ: Regulating Salmonella Adaptation to Host Microenvironments." In Signal Transduction and Bacterial Virulence, 61–77. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-662-22406-9_5.

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Bährle-Rapp, Marina. "phot(o)..., Phot(o)..." In Springer Lexikon Kosmetik und Körperpflege, 424. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_7933.

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Raffalli, Christophe, and Paul Rozière. "PhoX." In The Seventeen Provers of the World, 67–71. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11542384_11.

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Weik, Martin H. "phon." In Computer Science and Communications Dictionary, 1264. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_13951.

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Phon, Kaseka. "Phon, Kaseka." In Encyclopedia of Global Archaeology, 8565–66. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-30018-0_185.

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Bausch, Cory C., and Andreas Pfaltz. "PHOX Ligands." In Privileged Chiral Ligands and Catalysts, 221–56. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527635207.ch6.

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Conference papers on the topic "PHOG"

1

Saad, Shymaa, Mohamed S. Yasein, Mohamed H. Mousa, and Hamed Nassar. "Pedestrian detection using shape context and PHOG." In 2014 9th International Conference on Computer Engineering & Systems (ICCES). IEEE, 2014. http://dx.doi.org/10.1109/icces.2014.7030972.

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Dhall, Abhinav, Akshay Asthana, Roland Goecke, and Tom Gedeon. "Emotion recognition using PHOG and LPQ features." In Gesture Recognition (FG 2011). IEEE, 2011. http://dx.doi.org/10.1109/fg.2011.5771366.

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Amirshahi, Seyed Ali, Michael Koch, Joachim Denzler, and Christoph Redies. "PHOG analysis of self-similarity in aesthetic images." In IS&T/SPIE Electronic Imaging. SPIE, 2012. http://dx.doi.org/10.1117/12.911973.

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Volk, T. R., and N. M. Rubinina. "Optical Damage Resistant Impurities in Lithium Niobate." In Photorefractive Materials, Effects, and Devices II. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/pmed.1993.tha.8.

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Investigations of damage resistant impurities in LiNbO3 crys­tals are of great interest both for practical applications and for understanding microscopic origin of photovoltaic anu phog torefractive centers.
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Li, Yu, Hui Ma, Chunxin Fang, and Wenhao Lv. "Fusion of PHOG and Gabor for facial expression recognition." In 2022 7th International Conference on Intelligent Computing and Signal Processing (ICSP). IEEE, 2022. http://dx.doi.org/10.1109/icsp54964.2022.9778553.

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Zhang, Jiulong, Lu Wang, and Xinran Wen. "Combination of GIST and PHOG Features for Calligraphy Styles Classification." In the 2019 4th International Conference. New York, New York, USA: ACM Press, 2019. http://dx.doi.org/10.1145/3330393.3330396.

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Jun Chen and Yang Bai. "Classification of smile expression using hybrid PHOG and Gabor features." In 2010 International Conference on Computer Application and System Modeling (ICCASM 2010). IEEE, 2010. http://dx.doi.org/10.1109/iccasm.2010.5622334.

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Liu, An, Maoyin Chen, and Weiquan Pan. "Crater detection algorithm with part PHOG features for safe landing." In 2012 International Conference on Systems and Informatics (ICSAI). IEEE, 2012. http://dx.doi.org/10.1109/icsai.2012.6223214.

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Wang, Hui, Jing Gao, Lifeng Tong, and Lijun Yu. "Facial expression recognition based on PHOG feature and sparse representation." In 2016 35th Chinese Control Conference (CCC). IEEE, 2016. http://dx.doi.org/10.1109/chicc.2016.7553957.

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Wu, Hongliang, Weimin Wu, Jiajin Peng, and Junyuan Zhang. "A novel image retrieval algorithm based on PHOG and LSH." In GREEN ENERGY AND SUSTAINABLE DEVELOPMENT I: Proceedings of the International Conference on Green Energy and Sustainable Development (GESD 2017). Author(s), 2017. http://dx.doi.org/10.1063/1.4992874.

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Reports on the topic "PHOG"

1

Walian, P. J. Electron crystallography of PhoE porin, an outer membrane, channel- forming protein from E. coli. Office of Scientific and Technical Information (OSTI), November 1989. http://dx.doi.org/10.2172/6365889.

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Granot, David, Richard Amasino, and Avner Silber. Mutual effects of hexose phosphorylation enzymes and phosphorous on plant development. United States Department of Agriculture, January 2006. http://dx.doi.org/10.32747/2006.7587223.bard.

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Research objectives 1) Analyze the combined effects of hexose phosphorylation and P level in tomato and Arabidopsis plants 2) Analyze the combined effects of hexose phosphorylation and P level in pho1 and pho2 Arabidopsis mutants 3) Clone and analyze the PHO2 gene 4) Select Arabidopsis mutants resistant to high and low P 5) Analyze the Arabidopsis mutants and clone the corresponding genes 6) Survey wild tomato species for growth characteristics at various P levels Background to the topic Hexose phosphorylating enzymes, the first enzymes of sugar metabolism, regulate key processes in plants such as photosynthesis, growth, senescence and vascular transport. We have previously discovered that hexose phosphorylating enzymes might regulate these processes as a function of phosphorous (P) concentration, and might accelerate acquisition of P, one of the most limiting nutrients in the soil. These discoveries have opened new avenues to gain fundamental knowledge about the relationship between P, sugar phosphorylation and plant development. Since both hexose phosphorylating enzymes and P levels affect plant development, their interaction is of major importance for agriculture. Due to the acceleration of senescence caused by the combined effects of hexose phosphorylation and P concentration, traits affecting P uptake may have been lost in the course of cultivation in which fertilization with relatively high P (30 mg/L) are commonly used. We therefore intended to survey wild tomato species for high P-acquisition at low P soil levels. Genetic resources with high P-acquisition will serve not only to generate a segregating population to map the trait and clone the gene, but will also provide a means to follow the trait in classical breeding programs. This approach could potentially be applicable for other crops as well. Major conclusions, solutions, achievements Our results confirm the mutual effect of hexose phosphorylating enzymes and P level on plant development. Two major aspects of this mutual effect arose. One is related to P toxicity in which HXK seems to play a major role, and the second is related to the effect of HXK on P concentration in the plant. Using tomato plants we demonstrated that high HXK activity increased leaf P concentration, and induced P toxicity when leaf P concentration increases above a certain high level. These results further support our prediction that the desired trait of high-P acquisition might have been lost in the course of cultivation and might exist in wild species. Indeed, in a survey of wild species we identified tomato species that acquired P and performed better at low P (in the irrigation water) compared to the cultivated Lycopersicon esculentum species. The connection between hexose phosphorylation and P toxicity has also been shown with the P sensitive species VerticordiaplumosaL . in which P toxicity is manifested by accelerated senescence (Silber et al., 2003). In a previous work we uncovered the phenomenon of sugar induced cell death (SICD) in yeast cells. Subsequently we showed that SICD is dependent on the rate of hexose phosphorylation as determined by Arabidopsis thaliana hexokinase. In this study we have shown that hexokinase dependent SICD has many characteristics of programmed cell death (PCD) (Granot et al., 2003). High hexokinase activity accelerates senescence (a PCD process) of tomato plants, which is further enhanced by high P. Hence, hexokinase mediated PCD might be a general phenomena. Botrytis cinerea is a non-specific, necrotrophic pathogen that attacks many plant species, including tomato. Senescing leaves are particularly susceptible to B. cinerea infection and delaying leaf senescence might reduce this susceptibility. It has been suggested that B. cinerea’s mode of action may be based on induction of precocious senescence. Using tomato plants developed in the course of the preceding BARD grant (IS 2894-97) and characterized throughout this research (Swartzberg et al., 2006), we have shown that B. cinerea indeed induces senescence and is inhibited by autoregulated production of cytokinin (Swartzberg et al., submitted). To further determine how hexokinase mediates sugar effects we have analyzed tomato plants that express Arabidopsis HXK1 (AtHXK1) grown at different P levels in the irrigation water. We found that Arabidopsis hexokinase mediates sugar signalling in tomato plants independently of hexose phosphate (Kandel-Kfir et al., submitted). To study which hexokinase is involved in sugar sensing we searched and identified two additional HXK genes in tomato plants (Kandel-Kfir et al., 2006). Tomato plants have two different hexose phosphorylating enzymes; hexokinases (HXKs) that can phosphorylate either glucose or fructose, and fructokinases (FRKs) that specifically phosphorylate fructose. To complete the search for genes encoding hexose phosphorylating enzymes we identified a forth fructokinase gene (FRK) (German et al., 2004). The intracellular localization of the four tomato HXK and four FRK enzymes has been determined using GFP fusion analysis in tobacco protoplasts (Kandel-Kfir et al., 2006; Hilla-Weissler et al., 2006). One of the HXK isozymes and one of the FRK isozymes are located within plastids. The other three HXK isozymes are associated with the mitochondria while the other three FRK isozymes are dispersed in the cytosol. We concluded that HXK and FRK are spatially separated in plant cytoplasm and accordingly might play different metabolic and perhaps signalling roles. We have started to analyze the role of the various HXK and FRK genes in plant development. So far we found that LeFRK2 is required for xylem development (German et al., 2003). Irrigation with different P levels had no effect on the phenotype of LeFRK2 antisense plants. In the course of this research we developed a rapid method for the analysis of zygosity in transgenic plants (German et al., 2003).
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