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Sybesma, Wilbert, Marjo Starrenburg, Michiel Kleerebezem, Igor Mierau, Willem M. de Vos, and Jeroen Hugenholtz. "Increased Production of Folate by Metabolic Engineering of Lactococcus lactis." Applied and Environmental Microbiology 69, no. 6 (June 2003): 3069–76. http://dx.doi.org/10.1128/aem.69.6.3069-3076.2003.
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ABSTRACT The dairy starter bacterium Lactococcus lactis is able to synthesize folate and accumulates large amounts of folate, predominantly in the polyglutamyl form. Only small amounts of the produced folate are released in the extracellular medium. Five genes involved in folate biosynthesis were identified in a folate gene cluster in L. lactis MG1363: folA, folB, folKE, folP, and folC. The gene folKE encodes the biprotein 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine pyrophosphokinase and GTP cyclohydrolase I. The overexpression of folKE in L. lactis was found to increase the extracellular folate production almost 10-fold, while the total folate production increased almost 3-fold. The controlled combined overexpression of folKE and folC, encoding polyglutamyl folate synthetase, increased the retention of folate in the cell. The cloning and overexpression of folA, encoding dihydrofolate reductase, decreased the folate production twofold, suggesting a feedback inhibition of reduced folates on folate biosynthesis.
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Hamada, Yohei, Yoshinori Sanada, and Takehiro Hirose. "Simple evaluation of the fold axis, axial plane, and interlimb angle from a borehole image log." Scientific Drilling 31 (October 28, 2022): 85–91. http://dx.doi.org/10.5194/sd-31-85-2022.
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Abstract. Folds and fractures are important structures that preserve information on the past stress evolution; however, folds remain largely unexplored. Studying folds remains challenging, as no simple and unified method can be used to evaluate fold parameters, which include the fold axis, axial plane, and interlimb angle with depth. In this study, we propose a method to calculate the fold parameters of cylindrical concentric folds by considering the point at which the bedding trend changes as an inflexion point of the fold. The inflexion point is identified from the analysis of bedding orientation, which can be obtained by borehole image log. The orientation of the fold axis and the axial plane were geometrically calculated based on the inflexion surfaces at both ends of the folds. The application of this method is illustrated using a simulated fold model. It is shown that these fold parameters are calculated using the depth of the fold and are reliable to a certain extent, despite the uncertainty of the inflexion points. Although the extraction method assumes cylindrical concentric folds, it can be applied to symmetric folds to estimate the orientation of the fold axis and axial planes. The method developed in this study is expected to have a wide range of applications in structural geology as it can estimate the fold parameters of each fold traversed by a borehole.
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Koretke, Kristin K., Robert B. Russell, and Andrei N. Lupas. "Fold recognition without folds." Protein Science 11, no. 6 (June 2002): 1575–79. http://dx.doi.org/10.1110/ps.3590102.
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Li, Chen-Chen, and Bin Liu. "MotifCNN-fold: protein fold recognition based on fold-specific features extracted by motif-based convolutional neural networks." Briefings in Bioinformatics 21, no. 6 (November 28, 2019): 2133–41. http://dx.doi.org/10.1093/bib/bbz133.
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Abstract Protein fold recognition is one of the most critical tasks to explore the structures and functions of the proteins based on their primary sequence information. The existing protein fold recognition approaches rely on features reflecting the characteristics of protein folds. However, the feature extraction methods are still the bottleneck of the performance improvement of these methods. In this paper, we proposed two new feature extraction methods called MotifCNN and MotifDCNN to extract more discriminative fold-specific features based on structural motif kernels to construct the motif-based convolutional neural networks (CNNs). The pairwise sequence similarity scores calculated based on fold-specific features are then fed into support vector machines to construct the predictor for fold recognition, and a predictor called MotifCNN-fold has been proposed. Experimental results on the benchmark dataset showed that MotifCNN-fold obviously outperformed all the other competing methods. In particular, the fold-specific features extracted by MotifCNN and MotifDCNN are more discriminative than the fold-specific features extracted by other deep learning techniques, indicating that incorporating the structural motifs into the CNN is able to capture the characteristics of protein folds.
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Watterson, Thomas, Stephen C. McFarlane, and Andrea L. Menicucci. "Vibratory Characteristics of Teflon-Injected and Noninjected Paralyzed Vocal Folds." Journal of Speech and Hearing Disorders 55, no. 1 (February 1990): 61–66. http://dx.doi.org/10.1044/jshd.5501.61.
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This study compared the vibratory characteristics of normal vocal folds, Teflon-injected paralyzed vocal folds, and noninjected paralyzed vocal folds. Laryngeal videostroboscopy under eight phonatory conditions showed that the Teflon-injected vocal folds were adynamic. The noninjected vocal folds, however, vibrated during each of the phonatory conditions although not necessarily like a normal vocal fold. In terms of vocal fold physiology, it appeared that the noninjected paralyzed vocal folds were too compliant, whereas the Teflon-injected vocal folds were too stiff. Because vocal fold paralysis is often treated in voice therapy with "digital manipulation" and "head turning," the effect of these techniques on vocal fold vibration was also studied. The results showed that digital manipulation was superior to head turning for improving glottal closure but that neither technique appeared to influence the periodicity, amplitude, or extent of vocal fold vibration for either the injected or noninjected vocal folds.
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Abdullah Al, Walid Abdullah, Wonjae Cha, and Il Dong Yun. "Reinforcement Learning Based Vocal Fold Localization in Preoperative Neck CT for Injection Laryngoplasty." Applied Sciences 13, no. 1 (December 25, 2022): 262. http://dx.doi.org/10.3390/app13010262.
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Transcutaneous injection laryngoplasty is a well-known procedure for treating a paralyzed vocal fold by injecting augmentation material to it. Hence, vocal fold localization plays a vital role in the preoperative planning, as the fold location is required to determine the optimal injection route. In this communication, we propose a mirror environment based reinforcement learning (RL) algorithm for localizing the right and left vocal folds in preoperative neck CT. RL-based methods commonly showed noteworthy outcomes in general anatomic landmark localization problems in recent years. However, such methods suggest training individual agents for localizing each fold, although the right and left vocal folds are located in close proximity and have high feature-similarity. Utilizing the lateral symmetry between the right and left vocal folds, the proposed mirror environment allows for a single agent for localizing both folds by treating the left fold as a flipped version of the right fold. Thus, localization of both folds can be trained using a single training session that utilizes the inter-fold correlation and avoids redundant feature learning. Experiments with 120 CT volumes showed improved localization performance and training efficiency of the proposed method compared with the standard RL method.
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Nishina, Takumi, Megumi Nakajima, Masaki Sasai, and George Chikenji. "The Structural Rule Distinguishing a Superfold: A Case Study of Ferredoxin Fold and the Reverse Ferredoxin Fold." Molecules 27, no. 11 (May 31, 2022): 3547. http://dx.doi.org/10.3390/molecules27113547.
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Superfolds are folds commonly observed among evolutionarily unrelated multiple superfamilies of proteins. Since discovering superfolds almost two decades ago, structural rules distinguishing superfolds from the other ordinary folds have been explored but remained elusive. Here, we analyzed a typical superfold, the ferredoxin fold, and the fold which reverses the N to C terminus direction from the ferredoxin fold as a case study to find the rule to distinguish superfolds from the other folds. Though all the known structural characteristics for superfolds apply to both the ferredoxin fold and the reverse ferredoxin fold, the reverse fold has been found only in a single superfamily. The database analyses in the present study revealed the structural preferences of αβ- and βα-units; the preferences separate two α-helices in the ferredoxin fold, preventing their collision and stabilizing the fold. In contrast, in the reverse ferredoxin fold, the preferences bring two helices near each other, inducing structural conflict. The Rosetta folding simulations suggested that the ferredoxin fold is physically much more realizable than the reverse ferredoxin fold. Therefore, we propose that minimal structural conflict or minimal frustration among secondary structures is the rule to distinguish a superfold from ordinary folds. Intriguingly, the database analyses revealed that a most stringent structural rule in proteins, the right-handedness of the βαβ-unit, is broken in a set of structures to prevent the frustration, suggesting the proposed rule of minimum frustration among secondary structural units is comparably strong as the right-handedness rule of the βαβ-unit.
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Mohammad, Tabrez Anwar Shamim, and Hampapathalu Adimurthy Nagarajaram. "A Hierarchical Approach to Protein Fold Prediction." Journal of Integrative Bioinformatics 8, no. 1 (March 1, 2011): 66–77. http://dx.doi.org/10.1515/jib-2011-185.
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Summary Fold recognition, assigning novel proteins to known structures, forms an important component of the overall protein structure discovery process. The available methods for protein fold recognition are limited by the low fold-coverage and/or low prediction accuracies. We describe here a new Support Vector Machine (SVM)-based method for protein fold prediction with high prediction accuracy and high fold-coverage. The new method of fold prediction with high fold-coverage was developed by training and testing on a large number of folds in order to make the method suitable for large scale fold predictions. However, presence of large number of folds in the training set made the classification task difficult as a consequence of increased complexity involved in binary classifications of SVMs. In order to overcome this complexity we adopted a hierarchical approach where fold-prediction is made in two steps. At the first step structural class of the query is predicted and at the second step fold is predicted within the predicted structural class. This decreased the complexity of the classification problem and also improved the overall fold prediction accuracy. To the best of our knowledge this is the first taxonomic fold recognition method to cover over 700 protein-folds and gives prediction accuracy of around 70% on a benchmark dataset. Since the new method gives rise to state of the art prediction performance and hence can be very useful for structural characterization of proteins discovered in various genomes.
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Przybylski, Dariusz, and Burkhard Rost. "Improving Fold Recognition Without Folds." Journal of Molecular Biology 341, no. 1 (July 2004): 255–69. http://dx.doi.org/10.1016/j.jmb.2004.05.041.
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Cannas da Silva, Ana. "Fold-forms for four-folds." Journal of Symplectic Geometry 8, no. 2 (2010): 189–203. http://dx.doi.org/10.4310/jsg.2010.v8.n2.a3.
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Alimetov, H. A., R. A. Zagidullina, and M. G. Raupov. "Vocal fold nodes and functional dysphonias." Kazan medical journal 76, no. 1 (January 15, 1995): 44–45. http://dx.doi.org/10.17816/kazmj82718.
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The connection between the formation of vocal fold nodes and change of normal tonus of external larynx muscles is found. In dys- phonias the true vocal folds mucosa is traumatized in friction of tightened folds (hypertonus dysphonia) as well as weakened folds (hypotonus dysphonia) resulting in the formation of vocal fold nodes.
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Ward, Ayyed Hussein, Thair Mudhir Fahmi, and Hasnaa Saleh Khalaf. "Variation of the Anticlines Vergency in the Iraqi Zagros Folds Belt and Its Tectonic Indications." Tikrit Journal of Pure Science 25, no. 2 (March 17, 2020): 64. http://dx.doi.org/10.25130/j.v25i2.959.
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Folds of northern Iraq are considered integral part for the Western Zagros Fold – Thrust Belt. The growth of these folds was due to inversion displacement on inherited listric faults. This research deal with the relationship between the folds vergency and the faults that propagated folds, where that the dip of the back limb (gentle limb) for the fold is parallel to the thrust fault surface that propagated the fold, and the vergency of the fold determined by the forelimb (steep limb) situation. As a results, the folds of the high folded zone and of the western part of the low folded zone showed suture ( N and NE) vergency and foreland (S and SW) vergency, while the eastern part of the low fold zone showed foreland (S and SW) vergency only. The appearance of the suture and foreland vergency within the high folds considered as indication to the high tectonic development conformable with the location of these folds in the Iraqi Zagros Fold Belt, while the appearance of the suture and foreland vergency in the western part of the low folded zone attributed to the more tectonic development of this part in comparison with the eastern part of the zone that there folds appeared foreland vergencies only, or to the influence of the evaporite beds for Fatha formation in this part.
http://dx.doi.org/10.25130/tjps.25.2020.031
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Ayyed Hussein Ward, Thair Mudhir Fahmi, and Hasnaa Saleh Khalaf. "Variation of the Anticlines Vergency in the Iraqi Zagros Folds Belt and Its Tectonic Indications." Tikrit Journal of Pure Science 25, no. 2 (March 17, 2020): 64–70. http://dx.doi.org/10.25130/tjps.v25i2.237.
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Folds of northern Iraq are considered integral part for the Western Zagros Fold – Thrust Belt. The growth of these folds was due to inversion displacement on inherited listric faults. This research deal with the relationship between the folds vergency and the faults that propagated folds, where that the dip of the back limb (gentle limb) for the fold is parallel to the thrust fault surface that propagated the fold, and the vergency of the fold determined by the forelimb (steep limb) situation. As a results, the folds of the high folded zone and of the western part of the low folded zone showed suture ( N and NE) vergency and foreland (S and SW) vergency, while the eastern part of the low fold zone showed foreland (S and SW) vergency only. The appearance of the suture and foreland vergency within the high folds considered as indication to the high tectonic development conformable with the location of these folds in the Iraqi Zagros Fold Belt, while the appearance of the suture and foreland vergency in the western part of the low folded zone attributed to the more tectonic development of this part in comparison with the eastern part of the zone that there folds appeared foreland vergencies only, or to the influence of the evaporite beds for Fatha formation in this part.
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Kehlenbeck, M. M. "Folds and folding in the Beardmore–Geraldton fold belt." Canadian Journal of Earth Sciences 23, no. 2 (February 1, 1986): 158–71. http://dx.doi.org/10.1139/e86-019.
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The Beardmore–Geraldton fold belt forms a transitional crustal segment between the Quetico and Wabigoon subprovinces of the Canadian Shield.Bedding surfaces (So) and a bedding-plane schistosity (S1) were folded into asymmetrical to recumbent early folds. These folds were refolded by a later F2 folding episode. The F2 folds possess a penetrative axial-planar schistosity (S2) that is subvertical and generally strikes east–west. F2 hinge lines coincide closely with the axial direction of the early folds.The "structural facing direction (sensu Borradaile)" of F2 folds is either east or west. Folds with consistent facing directions are confined to distinct panels. Panels containing F2 folds with opposing facing directions are in sharp contact with each other. In several panels F2 folds face upward through sideways to downward.Modification of F2 buckle folds by homogeneous compressive strain components produced flattened flexure folds that closely approach folds of the similar fold model class.Further modification of fold shapes occurred in response to shear discontinuities that pervade the fold belt. Sheared F2 fold limbs commonly bind segments containing displaced F2 hinge zones of formerly adjacent folds. Zones of intense shearing show evidence of transposition of earlier fabric elements into the S2 schistosity. These zones of intense shear also form the boundaries of juxtaposed panels in which folds of variable orientation occur.The Beardmore–Geraldton fold belt is a terrain in which displacements along pervasive shear discontinuities of refolded folds and transposition of earlier fabric elements into the S2 schistosity have resulted in a pseudostratigraphy composed of disrupted and rotated segments of a pre-existing sequence of layered rocks.
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Leung, King-Shun. "Paper-folding and cutting activities to demonstrate five-fold symmetry." Mathematical Gazette 102, no. 555 (October 17, 2018): 413–21. http://dx.doi.org/10.1017/mag.2018.107.
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We can obtain a two-fold symmetric figure by folding a square sheet of paper in the middle and then cutting along some curves drawn on the paper. By making two perpendicular folds through the centre of the paper and then cutting, we can obtain a four-fold symmetric figure. We can also get an eight-fold symmetric figure by making a fold bisecting an angle made by the two perpendicular folds before cutting. But it is not possible to obtain a three-fold, five-fold or six-fold symmetric figure in this way; we need to make more folds before cutting. Making a three-fold (respectively five-fold and six-fold) figure involves the division of the angle at the centre (360°) of a square sheet of a paper into six (respectively ten and twelve) equal parts. In other words, we need to construct the angles 60°, 36° and 30°. But these angles cannot be obtained by repeated bisections of 180° by simple folding as in the making of two-fold, four-fold and eight-fold figures. In [1], we see that each of the constructions of 60° and 30° applies the fact that sin 30° = ½ and takes only a few simple folding steps. The construction of 36° is more tedious (see, for example, [2] and [3]) as sin 36° is not a simple fraction but an irrational number. In this Article, we show how to make, by paper-folding and cutting a regular pentagon, a five-pointed star and create any five-fold figure as we want. The construction obtained by dividing the angle at the centre of a square paper into ten equal parts is called apentagon base. We gained much insight from [2] and [3] when developing the method for making the pentagon base to be presented below.
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Wong, Ilene. "Fold after fold." Journal of General Internal Medicine 17, no. 7 (July 2002): 576–77. http://dx.doi.org/10.1046/j.1525-1497.2002.20357.x.
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Tanaka, Shinzo, Minoru Hirano, and Keichi Chijiwa. "Some Aspects of Vocal Fold Bowing." Annals of Otology, Rhinology & Laryngology 103, no. 5 (May 1994): 357–62. http://dx.doi.org/10.1177/000348949410300504.
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Bowing of the vocal fold frequently occurs in patients with vocal fold paralysis (VFP), those with sulcus vocalis, and those who have had laser surgery. Additionally, there are vocal folds that present bowing with no noticeable organic lesion. For the purpose of investigating the causes and mechanisms of vocal fold bowing, consecutive fiberscopic videorecordings of 127 patients with VFP, 33 with sulcus vocalis, 33 with laser surgery, and 33 with dysphonia having no clinically noticeable organic lesion were reviewed. Sixty-nine percent of the paralyzed vocal folds had bowing, and the occurrence of bowing was significantly related to the activity of the thyroarytenoid muscle as measured by electromyography. The cricothyroid activity had no significant relationship to vocal fold bowing. All vocal folds with sulcus presented with bowing. Thirty-five percent of the vocal folds that had had laser surgery had bowing. The extent of tissue removal was closely related to the occurrence of bowing. Twelve cases with no organic lesion had vocal fold bowing. Of these 12 patients, 8 were male and 9 were older than 60 years. Some aging process in the mucosa was presumed to be the cause of the bowing in this age group of patients without clinically noticeable organic lesions. Causes of vocal fold bowing in the younger group of patients without organic lesions were not determined in this study.
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O'GRADY, KIERAN G. "IRREDUCIBLE SYMPLECTIC 4-FOLDS NUMERICALLY EQUIVALENT TO (K3)[2]." Communications in Contemporary Mathematics 10, no. 04 (August 2008): 553–608. http://dx.doi.org/10.1142/s0219199708002909.
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First steps toward a classification of irreducible symplectic 4-folds whose integral 2-cohomology with 4-tuple cup product is isomorphic to that of (K3)[2]. We prove that any such 4-fold deforms to an irreducible symplectic 4-fold of Type A or Type B. A 4-fold of Type A is a double cover of a (singular) sextic hypersurface and a 4-fold of Type B is birational to a hypersurface of degree at most 12. We conjecture that Type B 4-folds do not exist.
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Wu, Jonny, Ken McClay, and Jose de Vera. "Growth of triangle zone fold-thrusts within the NW Borneo deep-water fold belt, offshore Sabah, southern South China Sea." Geosphere 16, no. 1 (December 19, 2019): 329–56. http://dx.doi.org/10.1130/ges02106.1.
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Abstract The NW Borneo deep-water fold-and-thrust belt, offshore Sabah, southern South China Sea, contains a structurally complex region of three to four seafloor ridges outboard of the shelf-slope break. Previous studies have suggested the seafloor ridges formed either above shale diapirs produced by mass movement of overpressured shales (i.e., mobile shale) or above an imbricate fold-and-thrust array. Here, we performed tectonostratigraphic analyses on a petroleum industry three-dimensional (3-D) seismic volume that imaged the full growth stratal record. We show fold growth history, deformation styles, along-strike structural variabilities, and synkinematic sedimentation during triangle zone–style fold growth. Nine seismic horizons within growth strata were mapped and correlated to petroleum industry seismostratigraphy. Synkinematic sedimentation interactions with growing folds and near-surface strains were analyzed from seismic attribute maps. We interpret that the seafloor structures were formed by imbricate thrusts above multiple detachments. We estimate ∼8 km minimum shortening since the late Miocene ca. 10 Ma. The folds show oversteepened fold forelimbs, back-rotated backlimbs, and forward-vergent (NW to NNW) “blind” thrust ramps that terminate within the growth strata. Fold cores show evidence of internal shear. Immature folds show detachment fold geometries, whereas mature folds show forelimb break thrusts, type I triangle zones, and rotated forward-vergent roof thrusts. Thrust linkages spaced ∼10 km apart were exploited as thrust top synkinematic sedimentation pathways; the linkages also partition near-surface strains. Our comprehensive, three-dimensional documentation of triangle zone fold growth and sedimentation in a deep-water fold belt highlights internal shear, multiple detachments, and opposite thrust vergence; mobile shales are not required to explain the deformation.
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Upendhar, S., J. Satyanarayana, and K. Vani Sree. "Cross Resistance Patterns Associated with Spinosad Resistant Helicoverpa armigera (Hubner) in South India." International Journal of Environment and Climate Change 13, no. 7 (May 8, 2023): 372–87. http://dx.doi.org/10.9734/ijecc/2023/v13i71889.
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Aim: To study the cross resistance patterns associated with Helicoverpa armigera (Hubner) in south India.
Study Design: Bioassay.
Place and Duration of Study: The experiment was carried out in the Department of Entomology, College of Agriculture, Rajendranagar, Hyderabad,Telangana from February 2010 to May 2011.
Methodology: Spinosad resistant Helicoverpa armigera population in F1 and F2 subjected to different insecticides to know the cross resistance patterns associated.
Results: American bollworm population of Mahaboobnagar has developed 0.308 and 0.646 folds and 0.284 and 0.624 folds in Raichur population as compared with the Nagpur baseline population at F1. Mahaboobnagar population displayed a negative cross resistance ratio of 0.677 fold to cypermethrin, 0.806 fold to methomyl, 0.935 fold to indoxacarb and positive cross resistance of 1.039 fold to spinosad, similar trend was followed in Raichur population with a negative cross resistance ratio of 0.918 fold to cypermethrin, 0.543 fold to methomyl, 0.642 fold to indoxacarb and 1.060 fold to spinosad. Further, the Nagpur population exihibited a similar trend with a negative cross resistance ratio of 0.604 fold to cypermethrin, 0.690 fold to methomyl, 0.570 fold to indoxacarb and positive cross resistance ratio of 1.077 fold to spinosad at F3.
Conclusion: The present study revealed that the continuous application of same insecticide across the generations increases the resistance from F1 to F3. Alternating the new chemistries with old conventional chemicals results in no cross resistance development as it was observed in all three populations studied.
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Seo, Meehee, Jung-A. Yoon, and Younhee Lee. "Issey Miyake fashion's fold characteristics through fold architecture." Research Journal of the Costume Culture 23, no. 5 (October 31, 2015): 861–75. http://dx.doi.org/10.7741/rjcc.2015.23.5.861.
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Hertegård, Stellan, Åke Dahlqvist, Claude Laurent, Assunta Borzacchiello, and Luigi Ambrosio. "Viscoelastic Properties of Rabbit Vocal Folds after Augmentation." Otolaryngology–Head and Neck Surgery 128, no. 3 (March 2003): 401–6. http://dx.doi.org/10.1067/mhn.2003.96.
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BACKGROUND: Vocal fold function is closely related to tissue viscoelasticity. Augmentation substances may alter the viscoelastic properties of vocal fold tissues and hence their vibratory capacity. OBJECTIVES: We sought to investigate the viscoelastic properties of rabbit vocal folds in vitro after injections of various augmentation substances. STUDY DESIGN AND SETTING: Polytetrafluoroethylene (Teflon), cross-linked collagen (Zyplast), and cross-linked hyaluronan, hylan b gel (Hylaform) were injected into the lamina propria and the thyroarytenoid muscle of rabbit vocal folds. Dynamic viscosity of the injected vocal fold as a function of frequency was measured with a Bohlin parallelplate rheometer during small-amplitude oscillation. RESULTS: All injected vocal folds showed a decreasing dynamic viscosity with increasing frequency. Vocal fold samples injected with hylan b gel showed the lowest dynamic viscosity, quite close to noninjected control samples. Vocal folds injected with polytetrafluoroethylene showed the highest dynamic viscosity followed by the collagen samples. CONCLUSIONS: The data indicated that hylan b gel in short-term renders the most natural viscoelastic properties to the vocal fold among the substances tested. This is of importance to restore/preserve the vibratory capacity of the vocal folds when glottal insufficiency is treated with injections.
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Jannah, Miftahul, Adi Suryadi, Muchtar Zafir, Randi Saputra, Ihsanul Hakim, Riki Ariyuswanto, and Ulfa Yusti. "Geological Structure Analysis to Determine the Direction of the Main Stress at Western Part of Kolok Mudik, Barangin District, Sawahlunto, West Sumatera." Journal of Geoscience, Engineering, Environment, and Technology 2, no. 1 (March 1, 2017): 46. http://dx.doi.org/10.24273/jgeet.2017.2.1.20.
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On the study area there are three types of structure, those are fault, fold and joint. Types of fault were found in the study area, reverse fault with the strike/dip is N215oE/75o, normal fault has a fault directions N22oE and N200oE with pitch 35o, and dextral fault with pitch 10o and strike N219oE. Fold and joint structures used to determine the direction of the main stress on the study area. Further, an analysis used stereonet for data folds and joints. So that from the data got three directions of main stress, those are Northeast – Southwest (T1), North – South (T2) and Southeast – Northwest (T3). On the Northeast – Southwest (T1) stress there are four geological structures, anticline fold at ST.3 , syncline folds at ST. 13a, ST. 13b, ST. 13c and ST. 33, chevron fold at ST. 44 and joint at ST. 2. On the North – South (T2) stress there are three geological structures, those are syncline fold at ST. 35, anticline fold at ST. 54 and joints at ST. 41, ST. 46 and ST. 47. On the Southeast – Northwest (T3) stress were also three geological structures, those are chevron fold at ST 42a, overturned fold at ST. 42b, syncline fold at ST. 42c and joints at ST. 5 and ST. 34.
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Cooper, Donald S., and Ingo R. Titze. "Generation and Dissipation of Heat in Vocal Fold Tissue." Journal of Speech, Language, and Hearing Research 28, no. 2 (June 1985): 207–15. http://dx.doi.org/10.1044/jshr.2802.207.
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The power dissipated in the vocal folds during phonation results from viscous loss in the fold tissues and can be estimated on the basis of a simplified representation of the geometry and movement of the folds. Assuming this power is converted into heat, it combines with the effects of muscle contraction, blood perfusion, and thermal conduction to the surface of the folds to determine fold temperature. To isolate the thermomechanical source of heat, the vocal folds of excised larynges were vibrated vertically over a range of frequencies and amplitudes, while the temperature rise in them was measured by inserted fine-wire thermocouples. The temperature rise observed was somewhat smaller than that predicted. This may be partly accounted for by convective and evaporative cooling of the vocal fold as it moved relative to the ambient air. Future studies should consider the time course of heating and vocal fold geometry in more detail.
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Dishman, Acacia F., Robert C. Tyler, Jamie C. Fox, Andrew B. Kleist, Kenneth E. Prehoda, M. Madan Babu, Francis C. Peterson, and Brian F. Volkman. "Evolution of fold switching in a metamorphic protein." Science 371, no. 6524 (December 31, 2020): 86–90. http://dx.doi.org/10.1126/science.abd8700.
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Metamorphic proteins switch between different folds, defying the protein folding paradigm. It is unclear how fold switching arises during evolution. With ancestral reconstruction and nuclear magnetic resonance, we studied the evolution of the metamorphic human protein XCL1, which has two distinct folds with different functions, making it an unusual member of the chemokine family, whose members generally adopt one conserved fold. XCL1 evolved from an ancestor with the chemokine fold. Evolution of a dimer interface, changes in structural constraints and molecular strain, and alteration of intramolecular protein contacts drove the evolution of metamorphosis. Then, XCL1 likely evolved to preferentially populate the noncanonical fold before reaching its modern-day near-equal population of folds. These discoveries illuminate how one sequence has evolved to encode multiple structures, revealing principles for protein design and engineering.
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Hirano, Shigeru, Susan Thibeault, Charles N. Ford, Diane M. Bless, and Shin-Ichi Kanemaru. "Hepatocyte Growth Factor and its Receptor C-Met in Rat and Rabbit Vocal Folds." Annals of Otology, Rhinology & Laryngology 111, no. 8 (August 2002): 661–66. http://dx.doi.org/10.1177/000348940211100801.
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Vocal fold fibrotic scar is characterized by fibrosis of the lamina propria and epithelium, and is difficult to treat. Hepatocyte growth factor (HGF) has antifibrotic activity and has received attention as a possible therapeutic alternative to treat fibrosis. In this study, in order to clarify whether HGF can be involved in vocal fold scarring, we examined the existence of HGF and its receptor, c-Met, in rat vocal folds, and then the activity of HGF in rabbit injured vocal folds, using immunohistochemistry and enzyme-linked immunosorbent assay. We found HGF and c-Met on epithelial cells and gland cells of the rat vocal folds. On the injured vocal folds of rabbits, little HGF was observed immediately after injury, but prominent activity occurred simultaneously with reepithelialization of the vocal fold mucosa on days 10 to 15. The activity of HGF was observed on fibroblasts in the lamina propria, as well as the epithelium. It is suggested that HGF in the vocal folds is produced by the fibroblasts and delivered to the epithelium. The implication of these findings is that HGF is involved in wound healing of the vocal fold, and may provide an alternative approach in preventing and treating vocal fold scarring.
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Sadowski, Michael I., and William R. Taylor. "Protein structures, folds and fold spaces." Journal of Physics: Condensed Matter 22, no. 3 (December 21, 2009): 033103. http://dx.doi.org/10.1088/0953-8984/22/3/033103.
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Stauffer, M. R. "Fold interference structures and coaptation folds." Tectonophysics 149, no. 3-4 (June 1988): 339–43. http://dx.doi.org/10.1016/0040-1951(88)90182-5.
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Gunter, Heather E., Robert D. Howe, Steven M. Zeitels, James B. Kobler, and Robert E. Hillman. "Measurement of Vocal Fold Collision Forces During Phonation." Journal of Speech, Language, and Hearing Research 48, no. 3 (June 2005): 567–76. http://dx.doi.org/10.1044/1092-4388(2005/039).
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Forces applied to vocal fold tissue as the vocal folds collide may cause tissue injury that manifests as benign organic lesions. A novel method for measuring this quantity in humans in vivo uses a low-profile force sensor that extends along the length and depth of the glottis. Sensor design facilitates its placement and stabilization so that phonation can be initiated and maintained while it is in place, with minimal interference in vocal fold vibration. In 2 individuals with 1 vibrating vocal fold and 1 nonvibrating vocal fold, peak collision force correlates more strongly with voice intensity than pitch. Vocal fold collision forces in 1 individual with 2 vibrating vocal folds are of the same order of magnitude as in previous studies. Correlations among peak collision force, voice intensity, and pitch were indeterminate in this participant because of the small number of data points. Sensor modifications are proposed so that it can be used to reliably estimate collision force in individuals with 2 vibrating vocal folds and with changing vocal tract conformations.
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Beura, D., S. K. Nanda, A. Parida, and L. Pattanayak. "Deformation Episodes in Iron Formation of Eastern Province of North Odisha Iron Ore Craton, Eastern India." Journal of Geosciences Research 8, no. 1 (January 1, 2023): 38–42. http://dx.doi.org/10.56153/g19088-022-0090-18.
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Banded Iron Formation (BIF), a bi-component rock of the Precambrian period is exposed along with iron ore in distinct geographical entities encircling the North Odisha Iron Ore Craton (NOIOC) in Odisha – Jharkhand states, eastern India. Iron formation of the eastern province is confined to Badampahar-Gorumahisani-Sulaipat belt. The litho assemblages belonging to this Iron Ore Group comprise of banded cherty quartzite, banded magnetite quartzite, banded magnetite grunerite quartzite, tremolite-actinolite schist and fuchsite quartzite. Deformations in phases affected the BIF members and associated rocks of the area resulting in successive fold structures. The first generation folds (F1) are characteristically tight and isoclinal having NE plunging axes. The second phase fold (F2) structures in the area with reference to first fold are co-axial, upright and tight to open in nature profusely overprinting the F1 folds are parallel to the general trend (NE-SW) of the belt. Axial plane of the third phase folds (F3) are gentle and broad warps having NW-SE trending axial planes and are found to be the last traceable ones in the area. trending in NW-SE direction are found to be the last traceable ones in the area having gentle and broad warps. The co-axial F1 and F2 folds along the general trend (NE-SW) of the belt are superposed by NW-SE trending F3 fold, which exhibits a geometric configuration as F1 // F2 F3. Such type of multiphase deformed terrain has produced many interference fold patterns in minor scale out of superposition i.e. dome and basin structures, hook shaped patterns, eyed fold and S, Z, and M shaped folds. The paper discusses the episodes of structural events and their signatures in the interference fold patterns in the eastern province of the NOIOC. Keywords: Banded Iron Formation, Badampahar-Gorumahisani-Sulaipat Belt, Deformation Episodes, NOIOC
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Zhang, Zhaoyan. "Vocal fold contact pattern during phonation and comparison to Hertzian contact theory." Journal of the Acoustical Society of America 154, no. 4_supplement (October 1, 2023): A243—A244. http://dx.doi.org/10.1121/10.0023423.
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The vocal folds are subject to repeated collision during phonation. The resulting contact pressure is often considered to play an important role in vocal fold injury, and has been measured in many experimental studies. In this study, vocal fold contact pattern and contact pressure during phonation were numerically investigated and compared to Hertzian contact theory. The results show that vocal fold contact in general occurs within a horizontal strip on medial surface, first appearing at the inferior medial surface and propagating upward. Because of the localized and traveling nature of vocal fold contact, sensors of a finite size may significantly underestimate the peak vocal fold contact pressure (by about as large as 80% for a sensor diameter of 2 mm), particularly for vocal folds of low transverse stiffness or thick medial surface. In general, the contact pressure increases with the size and curvature of the contact area, as predicted from Hertzian contact theory, indicating the possibility of estimating vocal fold contact pressure from medial surface kinematics. However, deviations from Hertzian theory were also observed, which need to be taken into consideration in estimating vocal fold contact pressure.
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Gray, Steven D., Steven M. Kelly, and Heather Dove. "Arytenoid Separation for Impaired Pediatric Vocal Fold Mobility." Annals of Otology, Rhinology & Laryngology 103, no. 7 (July 1994): 510–15. http://dx.doi.org/10.1177/000348949410300702.
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Impaired vocal fold motion may result from cricoarytenoid joint fixation, bilateral vocal fold paralysis, or interarytenoid scarring. Traditional surgical techniques have focused on lateralization or resection of the arytenoid for airway improvement. This paper discusses 3 cases of bilateral reduced vocal fold motion of neurogenic cause treated with posterior cricoid grafting to cause a wider resting position of the vocal folds and arytenoids. Airway improvement occurred in all. The voice results have been encouraging. Advantages of this procedure are that the vocal folds are symmetric, there is no vocal fold or joint scarring, and the larynx remains a candidate for electrical pacing when that becomes available. Acoustic and aerodynamic voice results are presented. The results should be considered preliminary.
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Lata, Swati, Ravindra Kumar, and Vaibhava Srivastava. "Geometric and strain analyses in folds of the area around Gankot, district Pithoragarh, Uttarakhand, India." Journal of Geoscience, Engineering, Environment, and Technology 4, no. 2-2 (July 25, 2019): 19. http://dx.doi.org/10.25299/jgeet.2019.4.2-2.2237.
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The study area around Gankot in Pithoragarh district of Uttarakhand belongs to the Thalkedar Limestone unit of Mandhali Formation, Tejam Group in Inner Sedimentary Zone of Lesser Himalaya, which exposes complexly folded and refolded structures. Geometric analysis carried out on the profile section of the fold tracing using dip isogon and orthogonal thickness parameters revealed presence of all the fold geometry suggested by Ramsay (1967) however the class 3 followed by class 1B are the most dominant classes in the study area when individual layers of the fold were studied. The study of folds as multilayered unit reveals that folds in study area belong to strongly non-analogous fold class of anisodeviatoric folds. In fold, the strain analysis has been done by drawing strain ellipse obtained by Inverse Thickness Method which is useful in estimating flattening strain even when the flattening is imposed obliquely to the fold’s axial trace. The finite two-dimensional flattening strain ratio (Rs) value ranged between 1 and 3.14 with an average Rs value of 1.60. The method of Srivastava and Gairola (2003) has also been used to obtain shear strain and flattening strain for the multilayered folds of study area. The results reveal that the multilayered folds around Gankot area are moderately flattened with mean flatting strain varying between 1.06 and 2.28. A very high degree of variation in shearing ranging about 70o in both clockwise and anticlockwise directions has been noticed. The shear strains (γ) in folds have been found to vary between -2.75 to + 3.27 with an average of +0.33. The shearing and strain patterns are suggestive that the most dominant folding mechanism has been the flexure-shear for the folds of the study area which are overprinted by the fold flattening and other subsequent deformations.
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Sakthivel, S., and V. Prabhu. "Optimal Deep Learning-Based Vocal Fold Disorder Detection and Classification Model on High-Speed Video Endoscopy." Journal of Healthcare Engineering 2022 (October 17, 2022): 1–12. http://dx.doi.org/10.1155/2022/4248938.
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The use of high-speed video-endoscopy (HSV) in the study of phonatory processes linked to speech needs the precise identification of vocal fold boundaries at the time of vibration. The HSV is a unique laryngeal imaging technology that captures intracycle vocal fold vibrations at a higher frame rate without the need for auditory inputs. The HSV is also effective in identifying the vibrational characteristics of the vocal folds with an increased temporal resolution during retained phonation and flowing speech. Clinically significant vocal fold vibratory characteristics in running speech can be retrieved by creating automated algorithms for extracting HSV-based vocal fold vibration data. The best deep learning-based diagnosis and categorization of vocal fold abnormalities is due to the usage of HSV (ODL-VFDDC). The suggested ODL-VFDDC technique starts with temporal segmentation and motion correction to identify vocalized regions from the HSV recording and gathers the position of movable vocal folds across frames. The attributes gathered are fed into the deep belief network (DBN) model. Furthermore, the agricultural fertility algorithm (AFA) is used to optimize the hyperparameter tuning of the DBN model, which improves classification results. In terms of vocal fold disorder classification, the testing results demonstrated that the ODL-VFDDC technique beats the other existing methodologies. The farmland fertility algorithm (FFA) is then used to accurately determine the glottal limits of vibrating vocal folds. The suggested method has successfully tracked the speech fold boundaries across frames with minimum processing cost and high resilience to picture noise. This method gives a way to look at how the vocal folds move during a connected speech that is completely done by itself.
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Alsop, G. I., R. Weinberger, S. Marco, and T. Levi. "Folding during soft-sediment deformation." Geological Society, London, Special Publications 487, no. 1 (February 4, 2019): 81–104. http://dx.doi.org/10.1144/sp487.1.
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AbstractThe detailed analysis of folding in rocks was in part pioneered by John Ramsay, and resulted in a range of techniques and criteria to define folds. Although folding of unlithified or ‘soft’ sediments is typically assumed to produce similar geometries to those in ‘hard rocks’, there has to date been little detailed analysis of such folds. The aim of this paper is therefore to investigate folds developed during soft-sediment deformation (SSD) by applying techniques established for the analysis of tectonic folds during hard-rock deformation (HRD). We use the Late Pleistocene Lisan Formation exposed around the Dead Sea as our case study, as the laminated lake sediments record intricacies of fold detail generated during seismically triggered slumping of mass transport deposits (MTDs) towards the depocentre of the basin. While it is frequently assumed that folds created during SSD are chaotic and form disharmonic structures, we provide analyses that show harmonic fold trains may form during slumping, although larger upright folds cannot be traced for significant distances and are more typically disharmonic. Our analysis also reveals a range of fold styles, with more competent detrital-rich layers displaying buckles (Class 1B), as well as upright Class 1A folds marked by thickened limbs. Class 1A buckle folds are generally considered to be created by flattening that overprints folds with an original Class 1B geometry. As thickened fold limbs are truncated by overlying erosive surfaces, the vertical flattening is considered to have occurred during the slump event. Different fold shapes may partially reflect variable flattening, depending on the original orientation of upright or recumbent folds, together with continued downslope-directed simple-shear deformation that modifies the fold geometry. Analysis of fold wavelength, amplitude and bed thickness allows us to plot strain contour maps, and indicates that beds defining slump folds display viscosity contrasts in the range of 50–250, which are similar to values estimated from folds created during HRD in metamorphic rocks. A range of refold patterns, similar to those established by John Ramsay in metamorphic rocks, are observed within slumps, and are truncated by the overlying sediments, indicating that they formed during a single progressive slump event rather than distinct ‘episodes’ of superimposed deformation. This study confirms that techniques developed for the analysis of folds created during HRD are equally applicable to those formed during SSD, and that resulting folds are generally indistinguishable from one another. Extreme caution should therefore be exercised when interpreting the origin of folds in the rock record where the palaeogeographical and tectonic contexts become increasingly uncertain, thereby leading to potential misidentification of folds created during SSD.
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SINTUBIN, M., F. BRODKOM, and D. LADURON. "Cleavage–fold relationships in the Lower Cambrian Tubize Group, southeast Anglo-Brabant Fold Belt (Lembeek, Belgium)." Geological Magazine 135, no. 2 (March 1998): 217–26. http://dx.doi.org/10.1017/s0016756898008358.
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Little is known about the cleavage–fold relationships in the Lower Palaeozoic Brabant Massif, primarily because of the scarcity of suitable exposures. Moreover, to date, folds have only been described in the Ordovician and Silurian sequences along the southern extremity of the basement. However, excavation works for the construction of the TGV(railway)-track south of Brussels created an opportunity to study cleavage–fold relationships in the Lower Cambrian terrigenous series (Tubize Group) in a more central part of the Brabant Massif. The structural features observed seemed inconsistent with the suspected regional trends. Primarily, a divergent cleavage fan was observed in a region thought to have a regular cleavage attitude. The symmetrical but divergent disposition of the cleavage with regard to the fold hinges is explained by flexural folding of a pre-existing bedding-parallel compaction fabric. Cleavage development and folding are considered synchronous. The divergent cleavage fan reflects local strain variations. Also the steeply plunging hinge lines of the open, subangular folds are seemingly inconsistent with the regional trend characterized by subhorizontal fold hinges. Taking into account the structural position of the fold assemblage in the subvertical limb of a large-scale, upright, isoclinal fold structure, the fold assemblage is interpreted as an incongruous parasitic feature. The steeply plunging hinge lines are considered to be caused by fold hinge rotation during progressive coaxial deformation. Although this incongruous fold assemblage with its divergent cleavage fan is localized, it provides important information on both local and regional deformation circumstances in this part of the Anglo-Brabant Fold Belt.
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Djukic, V. B., J. P. Milovanovic, A. P. Milovanovic, P. D. Stankovic, B. M. Pavlovic, M. M. Folic, and S. R. Blazic. "European laryngological society propose four types endoscopic supraglottic laryngectomy." Acta chirurgica Iugoslavica 56, no. 3 (2009): 85–88. http://dx.doi.org/10.2298/aci0903085d.
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The limited excision addresses small superficial lesions affecting free edge of the epiglottis, the aryepiglottic fold or the superior edge of the arytenoid. The median supraglottic laryngectomy excluding the pre-epiglottic space addresses small superficial T1 lesions of the endolaryngeal epiglottis. The incision line extends to the pre-epiglottic space but does not aim at removing the pre-epiglottic space entirely. The pharyngo-epiglottic folds, aryepiglottic folds, and ventricular folds are preserved. The median supraglottic laryngectomy including the pre-epiglottic space addresses T1 and T2 lesions of the endolaryngeal epiglottis. The entire pre-epiglottic space is removed as far as possible. Depending on extent of the lesion, the resection can include one or two ventricular bands and the aryepiglottic folds. The lateral supraglottic laryngectomy addresses lesions affecting the three folds or T1 and T2 lesions of the aryepiglottic fold. The procedure removes free edge of the epiglottis ipsilateral to the lesion, the area of the three folds and the aryepiglottic fold. The resection can include the inner wall and anterior angle og the pyriform sinus, the entire ventricular fold and the arytenoid (provided it is mobile).
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Wolf, Yuri I., Steven E. Brenner, Paul A. Bash, and Eugene V. Koonin. "Distribution of Protein Folds in the Three Superkingdoms of Life." Genome Research 9, no. 1 (January 1, 1999): 17–26. http://dx.doi.org/10.1101/gr.9.1.17.
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A sensitive protein-fold recognition procedure was developed on the basis of iterative database search using the PSI-BLAST program. A collection of 1193 position-dependent weight matrices that can be used as fold identifiers was produced. In the completely sequenced genomes, folds could be automatically identified for 20%–30% of the proteins, with 3%–6% more detectable by additional analysis of conserved motifs. The distribution of the most common folds is very similar in bacteria and archaea but distinct in eukaryotes. Within the bacteria, this distribution differs between parasitic and free-living species. In all analyzed genomes, the P-loop NTPases are the most abundant fold. In bacteria and archaea, the next most common folds are ferredoxin-like domains, TIM-barrels, and methyltransferases, whereas in eukaryotes, the second to fourth places belong to protein kinases, β-propellers and TIM-barrels. The observed diversity of protein folds in different proteomes is approximately twice as high as it would be expected from a simple stochastic model describing a proteome as a finite sample from an infinite pool of proteins with an exponential distribution of the fold fractions. Distribution of the number of domains with different folds in one protein fits the geometric model, which is compatible with the evolution of multidomain proteins by random combination of domains.[Fold predictions for proteins from 14 proteomes are available on the World Wide Web atftp://ncbi.nlm.nih.gov/pub/koonin/FOLDS/index.html. The FIDs are available by anonymous ftp at the same location.]
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Hapner, Edie R., and Adam Klein. "A Synopsis of the Management of Vocal Fold Scar." Perspectives on Voice and Voice Disorders 19, no. 1 (March 2009): 15–23. http://dx.doi.org/10.1044/vvd19.1.15.
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Abstract Vocal fold scarring remains one of the greatest therapeutic challenges in laryngology and voice therapy. The loss of superior lamina propria results in a change in the pliability of the vocal folds with changes in glottal configuration, glottal closure, and reduced to absent mucosal wave motion. This results in dysphonia of varying severities including breathiness, roughness, loss of pitch range, and flexibility. The aim of this article is to present a brief review of vocal fold architecture and a discussion of the etiologies of vocal fold scarring. Methods to evaluate vocal fold scarring are presented with examples of findings in laryngoscopic, acoustic, aerodynamic, and perceptual assessments. Medical, surgical, and behavioral treatment for vocal folds scaring including sample therapy tasks are included.
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Liu, Bin, Chen-Chen Li, and Ke Yan. "DeepSVM-fold: protein fold recognition by combining support vector machines and pairwise sequence similarity scores generated by deep learning networks." Briefings in Bioinformatics 21, no. 5 (October 28, 2019): 1733–41. http://dx.doi.org/10.1093/bib/bbz098.
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Abstract Protein fold recognition is critical for studying the structures and functions of proteins. The existing protein fold recognition approaches failed to efficiently calculate the pairwise sequence similarity scores of the proteins in the same fold sharing low sequence similarities. Furthermore, the existing feature vectorization strategies are not able to measure the global relationships among proteins from different protein folds. In this article, we proposed a new computational predictor called DeepSVM-fold for protein fold recognition by introducing a new feature vector based on the pairwise sequence similarity scores calculated from the fold-specific features extracted by deep learning networks. The feature vectors are then fed into a support vector machine to construct the predictor. Experimental results on the benchmark dataset (LE) show that DeepSVM-fold obviously outperforms all the other competing methods.
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Porter, Lauren L., and Loren L. Looger. "Extant fold-switching proteins are widespread." Proceedings of the National Academy of Sciences 115, no. 23 (May 21, 2018): 5968–73. http://dx.doi.org/10.1073/pnas.1800168115.
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A central tenet of biology is that globular proteins have a unique 3D structure under physiological conditions. Recent work has challenged this notion by demonstrating that some proteins switch folds, a process that involves remodeling of secondary structure in response to a few mutations (evolved fold switchers) or cellular stimuli (extant fold switchers). To date, extant fold switchers have been viewed as rare byproducts of evolution, but their frequency has been neither quantified nor estimated. By systematically and exhaustively searching the Protein Data Bank (PDB), we found ∼100 extant fold-switching proteins. Furthermore, we gathered multiple lines of evidence suggesting that these proteins are widespread in nature. Based on these lines of evidence, we hypothesized that the frequency of extant fold-switching proteins may be underrepresented by the structures in the PDB. Thus, we sought to identify other putative extant fold switchers with only one solved conformation. To do this, we identified two characteristic features of our ∼100 extant fold-switching proteins, incorrect secondary structure predictions and likely independent folding cooperativity, and searched the PDB for other proteins with similar features. Reassuringly, this method identified dozens of other proteins in the literature with indication of a structural change but only one solved conformation in the PDB. Thus, we used it to estimate that 0.5–4% of PDB proteins switch folds. These results demonstrate that extant fold-switching proteins are likely more common than the PDB reflects, which has implications for cell biology, genomics, and human health.
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Bailly, Lucie, Nathalie Henrich Bernardoni, Frank Müller, Anna-Katharina Rohlfs, and Markus Hess. "Ventricular-Fold Dynamics in Human Phonation." Journal of Speech, Language, and Hearing Research 57, no. 4 (August 2014): 1219–42. http://dx.doi.org/10.1044/2014_jslhr-s-12-0418.
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Purpose In this study, the authors aimed (a) to provide a classification of the ventricular-fold dynamics during voicing, (b) to study the aerodynamic impact of these motions on vocal-fold vibrations, and (c) to assess whether ventricular-fold oscillations could be sustained by aerodynamic coupling with the vocal folds. Method A 72-sample database of vocal gestures accompanying different acoustical events comprised high-speed cinematographic, audio, and electroglottographic recordings of 5 subjects. Combining the physiological correlates with a theoretical model of phonation, the vocal–ventricular aerodynamic interactions were investigated. Results A ventricular-fold motion is found during (de)crescendos, shout, throat singing, yodel, growls, and glides with transitions between registers. Three main types of dynamics are identified: slow nonoscillatory motion and fast oscillatory motion with aperiodical or periodical vibrations. These patterns accompany a change in voice quality, pitch, and/or intensity. Alterations of glottal-oscillatory amplitude, frequency, and contact were predicted. It is shown that a ventricular oscillation can be initiated and sustained by aerodynamic coupling with the vocal folds. Conclusions Vocal–ventricular aerodynamic interactions can alter, enhance, or suppress vocal-fold vibrations or leave them unchanged, depending on the ventricular-fold dynamics involved. Depending on its variation in time, a similar level of ventricular-fold adduction impacts the glottal vibratory magnitude and contact much differently.
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Dishman, Acacia F., Jie He, Brian F. Volkman, and Anna R. Huppler. "Metamorphic Protein Folding Encodes Multiple Anti-Candida Mechanisms in XCL1." Pathogens 10, no. 6 (June 17, 2021): 762. http://dx.doi.org/10.3390/pathogens10060762.
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Candida species cause serious infections requiring prolonged and sometimes toxic therapy. Antimicrobial proteins, such as chemokines, hold great interest as potential additions to the small number of available antifungal drugs. Metamorphic proteins reversibly switch between multiple different folded structures. XCL1 is a metamorphic, antimicrobial chemokine that interconverts between the conserved chemokine fold (an α–β monomer) and an alternate fold (an all-β dimer). Previous work has shown that human XCL1 kills C. albicans but has not assessed whether one or both XCL1 folds perform this activity. Here, we use structurally locked engineered XCL1 variants and Candida killing assays, adenylate kinase release assays, and propidium iodide uptake assays to demonstrate that both XCL1 folds kill Candida, but they do so via different mechanisms. Our results suggest that the alternate fold kills via membrane disruption, consistent with previous work, and the chemokine fold does not. XCL1 fold-switching thus provides a mechanism to regulate the XCL1 mode of antifungal killing, which could protect surrounding tissue from damage associated with fungal membrane disruption and could allow XCL1 to overcome candidal resistance by switching folds. This work provides inspiration for the future design of switchable, multifunctional antifungal therapeutics.
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Mehta, Tristan, and Gowrav Gowda. "Treating nasolabial folds with dermal fillers: a holistic approach." Journal of Aesthetic Nursing 8, no. 6 (July 2, 2019): 272–75. http://dx.doi.org/10.12968/joan.2019.8.6.272.
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There are multiple surgical and non-surgical ways to treat the nasolabial fold. Traditionally, the non-surgical way of treating nasolabial folds was through careful placement of hyaluronic acid fillers directly to the fold. Our understanding of the facial ageing process and facial anatomy has enabled us to evolve our technique so that nasolabial fold treatments are safer for patients and deliver better clinical outcomes. By treating nasolabial folds indirectly, by addressing the changes that occur through aging, the aesthetic practitioner can achieve more natural and effective reduction in the fold. Indirect treatment of the nasolabial fold requires addressing the bony resorption, deep fat and superficial fat volume loss. Through better understanding of the facial aging process, we are entering an era where more practitioners are treating the cause of a particular line than treating it directly. This has the benefit of creating a more balanced and natural result with longer lasting rejuvenation.
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DEBACKER, Timothy. "Folds trending at various angles to the transport direction in the Marcq area, Brabant Massif, Belgium." Geologica Belgica 2, no. 3-4 (June 1, 2000): 159–72. http://dx.doi.org/10.20341/gb.2014.015.
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Generally folds in fold belts are expected to trend approximately parallel to the main axis of the fold belt. Indeed, most of the fold hinge lines along the southern rim of the poorly exposed Lower Palaeozoic Brabant Massif reflect the general trend of the massif (transverse folds). However, in some places, folds exist oriented at high angles to the general trend of the massif (longitudinal folds). New field work in the Marcq area, situated in the southwestern part of the Brabant Massif, reveals the presence of transverse, longitudinal and oblique asymmetric folds. Direct field observations, combined with borehole and geophysical data, indicate the presence of a low-angle high-strain zone, interpreted as a reverse shear zone. The various fold orientations are explained by means of differential movement within this shear zone. All the structural features are considered to be the result of one single progressive deformation. Although this shear zone is probably of minor regional significance, the kinematic inferences made in the Marcq area may have important implications for the outline of the overall tectonic image of the southwestern part of the Brabant Massif.
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CHEN, PENG, CHUNMEI LIU, LEGAND BURGE, MOHAMMAD MAHMOOD, WILLIAM SOUTHERLAND, and CLAY GLOSTER. "PROTEIN FOLD CLASSIFICATION WITH GENETIC ALGORITHMS AND FEATURE SELECTION." Journal of Bioinformatics and Computational Biology 07, no. 05 (October 2009): 773–88. http://dx.doi.org/10.1142/s0219720009004321.
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Protein fold classification is a key step to predicting protein tertiary structures. This paper proposes a novel approach based on genetic algorithms and feature selection to classifying protein folds. Our dataset is divided into a training dataset and a test dataset. Each individual for the genetic algorithms represents a selection function of the feature vectors of the training dataset. A support vector machine is applied to each individual to evaluate the fitness value (fold classification rate) of each individual. The aim of the genetic algorithms is to search for the best individual that produces the highest fold classification rate. The best individual is then applied to the feature vectors of the test dataset and a support vector machine is built to classify protein folds based on selected features. Our experimental results on Ding and Dubchak's benchmark dataset of 27-class folds show that our approach achieves an accuracy of 71.28%, which outperforms current state-of-the-art protein fold predictors.
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Lesauskaitė, Vaiva, Virgilijus Uloza, Vykintas Liutkevičius, and Dalia Pangonytė. "Expression of matrix metalloproteinases (MMP-2 and MMP-9) in vocal fold polyps." Medicina 44, no. 4 (April 20, 2008): 322. http://dx.doi.org/10.3390/medicina44040042.
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Objective. Vocal fold polyps are the most common benign laryngeal lesions. Matrix metalloproteinases (MMP) play an important role in the physiological and pathological remodeling of tissues. The most important subgroup of MMP family consists of gelatinases A and B (MMP-2 and MMP-9). The objective of this study was investigation of the expression of MMP-2 and MMP-9 in vocal fold polyps and normal tissue of vocal folds. Material and methods. The immunohistochemical expression of MMP-2 and MMP-9 was investigated in specimens taken by endolaryngeal microsurgery from vocal fold polyps (n=30) and normal tissue of vocal fold (n=13, control group). Expression of MMP-2 and MMP-9, both in epithelium and stroma cells, was graded on a semiquantitative scale, ranging from 0 (no expression) to 6 points (high expression). Results. A statistically significant increase was observed in the expression of MMP-2 in stroma cells (P=0.0176) of vocal fold polyps compared to control vocal fold group, whereas no significant difference in the expression of MMP-2 was found in epithelium cells (P=0.1487). Comparison of expression of MMP-2 and MMP-9 in epithelium cells revealed a statistically significant increase in MMP-9 expression (P<0.01) in both groups. However, there was no statistically significant difference in the expression of MMP-9 between groups of vocal fold polyps and control vocal folds. Conclusion. Expression of MMP-2 in stroma was significantly higher in polyps than in normal tissue of vocal folds. Our data draw attention to the role of MMP-2 in the development of vocal fold polyps and necessity of further investigations to define its function in morphogenesis of laryngeal benign, premalignant, and malignant lesions.
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A. I. Prodanchuk. "PECULIARITIES OF FORMATION OF THE HARD PALATE FOLDS DURING THE SECOND AND THIRD TRIMESTER OF THE INTRAUTERINE DEVELOPMENT." Clinical anatomy and operative surgery 17, no. 3 (August 28, 2018): 64–68. http://dx.doi.org/10.24061/1727-0847.17.3.2018.10.
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A comprehensive study of anatomical-functional peculiarities of the cranial bones promotes implementation of new methods of performing radical and reconstructive-restorative surgery on the face and cranium. Objective: to determine peculiarities of formation of the hard palate folds structure in the fetal and early neonatal periods of human ontogenesis. Materials and methods. The study was conducted on 53 specimens of dead fetuses from 4 to 10 months of development and on 9 specimens of dead neonates by means of macro- and micro-section, preparing histological and topographic-anatomical sections, and morphometry. Formation of the hard palate folds during the second and third trimesters of the intrauterine development was found to consist of the following stages: epithelial thickening, penetration into the adjacent mesenchyme originating the rudiment of the fold; smoothing of the basal membrane and epithelial outgrowth over the surface with formation of the primary fold; condensation of mesenchyme cells under the fold apex; formation of fibrous stroma inside of the fold which is a peculiar core; epithelial smoothing to even thickness similar to that one embracing the areas between folds with formation of the final fold. At the end of the third trimester of the intrauterine development posterior transverse palatine folds become less marked, some of them disappear, and the anterior ones become more marked, closer and pressed one to another.
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Woodbridge, Kevin P., Saied Pirasteh, and Daniel R. Parsons. "Investigating Fold-River Interactions for Major Rivers Using a Scheme of Remotely Sensed Characteristics of River and Fold Geomorphology." Remote Sensing 11, no. 17 (August 29, 2019): 2037. http://dx.doi.org/10.3390/rs11172037.
Full textAbstract:
There are frequently interactions between active folds and major rivers (mean annual water discharges > 70 m3s−1). The major river may incise across the fold, to produce a water gap across the fold, or a bevelling (or lateral planation) of the top of the fold. Alternatively, the major river may be defeated to produce a diversion of the river around the fold, with wind gaps forming across the fold in some cases, or ponding of the river behind the fold. Why a river incises or diverts is often unclear, though influential characteristics and processes have been identified. A new scheme for investigating fold-river interactions has been devised, involving a short description of the major river, climate, and structural geology, and 13 characteristics of river and fold geomorphology: (1) Channel width at location of fold axis, w, (2) Channel-belt width at location of fold axis, cbw, (3) Floodplain width at location of fold axis, fpw, (4) Channel sinuosity, Sc, (5) Braiding index, BI, (6) General river course direction, RCD, (7) Distance from fold core to location of river crossing, C-RC, (8) Distance from fold core to river basin margin, C-BM, (9) Width of geological structure at location of river crossing, Wgs, (10) Estimate of erosion resistance of surface sediments/rocks and deeper sediments/rocks in fold, ERs, ERd, (11) Channel water surface slope at location of fold axis, s, (12) Average channel migration rate, Rm, (13) Estimate of fold total uplift rate, TUR. The first 10 geomorphological characteristics should be readily determinable for almost all major rivers using widely available satellite imagery and fine scale geological maps. This use of remote sensing allows a large number of major rivers to be investigated relatively easily, including those in remote or inaccessible areas, without recourse to expensive fieldwork. The last three geomorphological characteristics should be determinable for most major rivers where other data sources are available. This study demonstrates the methodology of this scheme, using the example of the major rivers Karun and Dez interacting with active folds in the foreland basin tectonic setting of lowland south-west Iran. For the rivers Karun and Dez (mean annual water discharges 575 m3s−1 and 230 m3s−1, respectively), it was found that geomorphological characteristics Nos. 2, 3 and 7 had statistically significant differences (p-value ≤ 0.05) between the categories of river incision across a fold and river diversion around a fold. This scheme should be used to investigate a variety of major rivers from across the globe. By comparing the same parameters for different major rivers, a better understanding of fold-river interactions will be achieved.
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Cullen, Jeff, Nathan Knox, Jacob Crouch, and Joseph Satterfield. "Polyphase Laramide Structures and Possible Folded Tertiary(?) Sills at Dagger mountain, Big Bend National Park, Texas." Compass: Earth Science Journal of Sigma Gamma Epsilon 85, no. 3 (November 12, 2013): 98–120. http://dx.doi.org/10.62879/c47584982.
Full textAbstract:
Dagger Mountain, in Sierra del Carmen within Big Bend National Park, Texas, is a 5 km-long, doubly-plunging, southwest-vergent anticline adjacent to a doubly plunging syncline. Dagger Mountain lies near the eastern margins of the Cordilleran orogen and the Basin and Range province. Mapping at 1:12,000 scale reveals details about three phases of Laramide and Basin and Range structures. Mapping and descriptive structural analysis complement previous mapping at 1:12,000 – 1:75,000 scales (Poth, 1979; Moustafa, 1988; Cooper and others, 2011; Turner and others, 2011; Maxwell and others, 1967). Four distinctive formations of Cretaceous age crop out on Dagger Mountain: Santa Elena Limestone, Del Rio Clay, Buda Limestone, and Boquillas Formation. At least two phaneritic, mafic, feldpathoid-rich sills intrude the Boquillas Formation. A similar, possibly correlative sill south of Dagger Mountain is dated at 32.47 ± 0.41 Ma ( 40Ar/39 Ar on groundmass; Morgan and Shanks, 2008). One well-exposed Dagger Mountain sill can be traced from one map-scale fold limb, through the hinge, and into the other limb. The Dagger Mountain anticline is a first-phase (D1) fold. D1 map- and outcrop-scale folds contain subvertical NNW-striking axial planes and subhorizontal fold axes. Second-phase (D2) folds produced NNW and SSE plunges of the DM anticline. D2 map- and outcrop-scale folds display subvertical NE-striking axial planes and subhorizontal fold axes. Third-phase (D3) high-angle faults strike NNW and NW and cross-cut D1 folds and Tertiary sills. Drag during D3 faulting produced D3 folds. Dagger Mountain structures are significant because: a) few polyphase folds have been documented in the Big Bend region, b) the west-verging Dagger Mountain anticline and other D1 folds show fault-propagation fold characteristics, c) the apparently folded Tertiary(?) sill suggests that Laramide deformation at Dagger Mountain is post-32 Ma and unusually recent. Alternatively, the sill could be as old as Cretaceous, or the sill could have intruded both limbs and hinge of an existing fold.