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Sample records for central incisors based

  1. Relationship of the lingual frenum to the mandibular central incisors

    PubMed Central

    Gupta, Swati; Garg, Sanchit; Tandan, Amrit; Dwivedi, Ravi; Gupta, Narendra Kumar; Agarwal, Garima

    2015-01-01

    Clinical implication The purpose of this study is to record the vertical distance between anterior attachment of lingual frenum and incisal edge of mandibular central incisors in dentulous subjects and then determine the mean vertical distance and to suggest guidelines for positioning of mandibular central incisors in complete dentures. Method In this study, 150 dentulous subjects (75 males and 75 females) were chosen based on predecided inclusion criteria. A mandibular cast was obtained from irreversible hydrocolloid impression in modified stock trays for each subject. All subjects were instructed to elevate the tongue while the impressions were made. The vertical distance between the anterior attachment of the lingual frenum and incisal edges of mandibular central incisors was measured on the casts and then the values were statistically analyzed. Result The distance between anterior attachment of lingual frenum (AALF) mesioincisal edge of mandibular central incisor (CI) in male, female and total (male+female) subjects was measured. In males it ranged from 7.3 to 8.9mm with mean (SD) 8.290.36mm while in females it ranged from 7.1 to 9.0mm with mean (SD) 8.210.38mm. Conclusion It is believed that the application of this anatomic relation can provide a reliable point for arranging and checking the position of the mandibular central incisors for complete dentures in patients with class I ridge relationship. PMID:25853047

  2. Treatment of impacted, rotated central incisors with removable appliance.

    PubMed

    Bayani, Shahin; Hashemi, Zahra; Khoramian, Somaye

    2013-01-01

    A 12-year-old girl was referred to the orthodontic department of Kerman dental school with a chief complaint of two unerupted upper left & right front teeth. Patient had no significant medical & Dental history. Intra oral and radiographic examination revealed missing of two maxillary permanent central incisors. Orthodontic treatment involved two phases: Phase 1 Impacted maxillary central incisors: surgical exposure and force eruption with removable appliance. Phase 2: whip appliance is used to correct rotation of right permanent maxillary incisor. PMID:23941031

  3. Solitary median maxillary central incisor (SMMCI) syndrome

    PubMed Central

    Hall, Roger K

    2006-01-01

    Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 1822 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated. PMID:16722608

  4. Treatment of an impacted dilacerated maxillary central incisor.

    PubMed

    Pavlidis, Dimitrios; Daratsianos, Nikolaos; Jäger, Andreas

    2011-03-01

    The diagnosis of an impacted incisor with dilaceration refers to a dental deformity characterized by an angulation between the crown and the root, causing noneruption of the incisor. In the past, surgical extraction was the first choice in treating severely dilacerated incisors. The purpose of this case report was to present the correction of a horizontally impacted and dilacerated central incisor through 2-stage crown exposure surgery combined with continuous-force orthodontic traction. The tooth was successfully moved into its proper position. The treatment is discussed, and the orthodontic implications are considered, with a review of the current literature on this topic. PMID:21392694

  5. Premolar transplantation to replace a missing central incisor.

    PubMed

    Cunha, Deise Lima; Masioli, Marco Antonio; Intra, João Batista Gagno; Roldi, Armelindo; Dardengo, Camila de Sousa; Miguel, Jose Augusto Mendes

    2015-03-01

    During childhood, the anterior maxilla is susceptible to injury, and the loss of incisors is one of the most serious injuries. In many cases, autotransplantation is the best alternative for children who lose an incisor during the growth phase. This case report describes the treatment of a boy who had a traumatic injury when he was 8 years old that resulted in avulsion of the maxillary right central incisor. When he sought treatment at age 10, the space was lost as was bone in the incisor region. Because he lacked space in the mandibular arch for proper tooth alignment, extractions were planned. One extracted premolar was transplanted into the space of the missing maxillary incisor area. The posttreatment results were good, and follow-up records 7 and 9 years after treatment showed healthy periodontal support and cortical bone gain in the transplanted tooth's buccal area. PMID:25726407

  6. Dental transposition of canine and lateral incisor and impacted central incisor treatment: A case report

    PubMed Central

    Gebert, Tarcisio Jacinto; Palma, Vinícius Canavarros; Borges, Alvaro Henrique; Volpato, Luiz Evaristo Ricci

    2014-01-01

    Introduction Dental transposition and impaction are disorders related to ectopic eruption or failure in tooth eruption, which can affect child physical, mental and social development and may be difficult to be clinically solved. Methods We describe a case of transposition between the upper left canine and lateral incisor associated with impaction of the central incisor on the same side, in a 12-year-old patient. Conservative treatment involving surgical-orthodontic correction of transposed teeth and traction of the central incisor was conducted. Conclusion The option of correcting transposition and orthodontic traction by means of the segmented arch technique with devices such as cantilever and TMA rectangular wire loops, although a complex alternative, was proved to be esthetically and functionally effective. PMID:24713567

  7. An efficient biomechanical approach for the management of an impacted maxillary central incisor.

    PubMed

    Chandhoke, Taranpreet K; Agarwal, Sachin; Feldman, Jonathan; Shah, Raja A; Upadhyay, Madhur; Nanda, Ravindra

    2014-08-01

    Treatment of an impacted maxillary central incisor poses a unique challenge to the orthodontist because of its position within the esthetic zone, requiring careful management of the soft tissues and an effective biomechanical setup for alignment. This article describes a novel method of extending an extrusion wire from cross tubes attached on the base archwire for forced eruption of impacted central incisors. The effectiveness and versatility of this method are demonstrated with 2 patients. PMID:25085308

  8. Multidisciplinary approach to a traumatized unerupted dilacerated maxillary central incisor.

    PubMed

    de Oliveira Ruellas, Antônio Carlos; Mattos, Claudia Trindade

    2012-07-01

    A patient with an impacted dilacerated maxillary left central incisor is presented. The 8-year-old girl also presented with protrusion of teeth and lips, posterior crossbite, anterior open bite, thumb-sucking habit, and transposition of the maxillary left lateral incisor and canine. The treatment consisted of a multidisciplinary approach, including surgery, orthodontics, endodontics, and prosthodontics. The dilacerated incisor was surgically exposed, tractioned, endodontically treated, and restored. Four premolars were extracted to correct the protrusion. The outcome was the accomplishment of a balanced and functional occlusion, resulting in a pleasant smile. PMID:22149545

  9. Neonatal nasal obstruction and a single maxillary central incisor.

    PubMed

    Levison, John; Neas, Katherine; Wilson, Meredith; Cooper, Peter; Wojtulewicz, Julian

    2005-07-01

    We present two neonates with nasal obstruction because of anterior choanal stenosis (congenital nasal pyriform aperture stenosis). An associated single maxillary central incisor was also shown on computed tomography imaging in the neonatal period. These midline anomalies are recognized minimal manifestations (microforms) of holoprosencephaly. We describe their neonatal investigation, multidisciplinary management and clinical course. PMID:16014147

  10. Elastic Band Causing Exfoliation of the Upper Permanent Central Incisors

    PubMed Central

    2015-01-01

    Objective. This study reports a case in which elastic band use culminated in the loss of the incisors. Case Report. An 11-year-old white girl was seen complaining of pain, with purulent discharge and severe tooth mobility. The bone destruction detected radiographically in the region, despite its single location and absence in posterior quadrants of the maxilla and/or mandible, was similar to that observed in Langerhans cell disease. To our surprise, an elastic band involving the midportion of the roots of the two upper central incisors was found during biopsy. The debris was removed and a metal wire was placed in permanent maxillary right and left incisors. The patient was followed up, but no improvement in tooth mobility was observed. Bone loss increased, and internal resorption and root exposure occurred, which culminated in the extraction of permanent maxillary right and left incisors. Conclusion. The present case highlights the fact that professionals sometimes are confronted by anamnestic reports never seen before. PMID:25874135

  11. Fragment Reattachment after Atypical Crown Fracture in Maxillary Central Incisor

    PubMed Central

    Vaz, Vanessa Torraca Peraro; Presoto, Cristina Dupim; Jordão, Keren Cristina Fagundes; Paleari, André Gustavo; Dantas, Andrea Abi-Rached; Segalla, José Claudio Martins; de Oliveira Junior, Osmir Batista

    2014-01-01

    Background. Fracture by trauma is one of the most common types of dental injury in the permanent dentition among children and teenagers. Aim. The aim of this study was to report the treatment performed to an atypical dental trauma case in a maxillary central incisor of a young patient by means of reattachment of the tooth fragment. Case Description. A 12-year-old male patient suffered a vertical crown fracture to the maxillary right central incisor. After clinical and radiographic examinations, a conservative restorative treatment which consisted in the reattachment of the tooth fragment with flow resin was performed in order to preserve the dental element and to obtain maximum aesthetics. Conclusion. The reattachment of fractured fragment is a fast and easy technique that can be used successfully as an option to restore dental element which suffered trauma. Clinical Significance. This technique restores the aesthetics and function of the dental element with minimal discomfort to the patient. PMID:25610663

  12. Surgical Management of Mandibular Central Incisors with Dumbbell Shaped Periapical Lesion: A Case Report

    PubMed Central

    Venigalla, Bhuvan Shome; Patil, Jayaprakash D.; Jayaprakash, Thumu; Chaitanya, C. H. Krishna; Kalluru, Rama S.

    2014-01-01

    Dental traumatic injuries may affect the teeth and alveolar bone directly or indirectly. Pulpal necrosis and chronic and apical periodontitis with cystic changes are the most common sequelae of the dental traumatic injuries, if the teeth are not treated immediately. This case report focuses on the conventional and surgical management of mandibular central incisors. A twenty-four-year-old male patient presented with pain in the mandibular central incisors. Radiographic examination revealed mandibular central incisors with dumbbell shaped periapical lesion. After root canal treatment, parendodontic surgery was performed for mandibular central incisors. After one-year recall examination, the teeth were asymptomatic and periapical lesion had healed. PMID:25105031

  13. Variation in Size and Form between Left and Right Maxillary Central Incisor Teeth

    PubMed Central

    Vadavadagi, Suneel V; Hombesh, M N; Choudhury, Gopal Krishna; Deshpande, Sumith; Anusha, C V; Murthy, D Kiran

    2015-01-01

    Background: To compare the variation in size of left and right maxillary central incisors for male patients (using digital calipers of 0.01 mm accuracy). To compare the variation in size of left and right maxillary central incisors for female patients (using digital calipers of 0.01 mm accuracy). To find out the difference between the maxillary central incisors of men and women. Its clinical applicability if difference exists. Materials and Methods: A total of 70 dental students of PMNM Dental College and Hospital were selected. Of 70 dental students, 40 male and 30 female were selected. Impressions were made for all subjects, using irreversible hydrocolloid (Algitex, manufacturer DPI, Batch-T-8804) using perforated stock metal trays. The mesiodistal crown width and cervical width were measured for each incisor and recorded separately for left and right teeth. The length was measured for each incisor and recorded separately for left and right maxillary central incisor using digitec height caliper. Results: The mean value of maximum crown length of maxillary left central incisor of male was greater in length compared with maxillary right central incisor. Mean value of maximum crown length for male patient right and left side was greater compared with maximum crown length of female patient. Conclusion: When compared the dimensions of teeth between two sex, male group shows larger values to female group. PMID:25859104

  14. Alveolar bone thickness around maxillary central incisors of different inclination assessed with cone-beam computed tomography

    PubMed Central

    Liu, Fang; Sun, Hong-jing; Lv, Pin; Cao, Yu-ming; Yu, Mo; Yue, Yang

    2015-01-01

    Objective To assess the labial and lingual alveolar bone thickness in adults with maxillary central incisors of different inclination by cone-beam computed tomography (CBCT). Methods Ninety maxillary central incisors from 45 patients were divided into three groups based on the maxillary central incisors to palatal plane angle; lingual-inclined, normal, and labial-inclined. Reformatted CBCT images were used to measure the labial and lingual alveolar bone thickness (ABT) at intervals corresponding to every 1/10 of the root length. The sum of labial ABT and lingual ABT at the level of the root apex was used to calculate the total ABT (TABT). The number of teeth exhibiting alveolar fenestration and dehiscence in each group was also tallied. One-way analysis of variance and Tukey's honestly significant difference test were applied for statistical analysis. Results The labial ABT and TABT values at the root apex in the lingual-inclined group were significantly lower than in the other groups (p < 0.05). Lingual and labial ABT values were very low at the cervical level in the lingual-inclined and normal groups. There was a higher prevalence of alveolar fenestration in the lingual-inclined group. Conclusions Lingual-inclined maxillary central incisors have less bone support at the level of the root apex and a greater frequency of alveolar bone defects than normal maxillary central incisors. The bone plate at the marginal level is also very thin. PMID:26445719

  15. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report.

    PubMed

    Pavuluri, Chaitanya; Nuvvula, Sivakumar

    2013-01-01

    Maxillary incisors are the most frequently injured teeth in the primary and permanent dentition. Stage of adolescence show a significant number of dental injuries as they engage in contact sports. Children with accident prone profile, i.e. class II division I or class I type II malocclusion are more prone for injuries because of the proclined maxillary incisors. Supernumerary teeth are those that are additional to the normal complement. They occur in single or multiple, unilateral or bilateral in either of the jaws. This paper reports the presence of an inverted supernumerary tooth in the right maxillary central incisor region with trauma involving both maxillary central incisors and also the management of the supernumerary tooth and traumatized teeth in a 14-year-old boy. How to cite this article: Pavuluri C, Nuvvula S. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report. Int J Clin Pediatr Dent 2013;6(1):30-32. PMID:25206184

  16. Influence of prefabricated post dimensions on restored maxillary central incisors.

    PubMed

    Rodrguez-Cervantes, P J; Sancho-Bru, J L; Barjau-Escribano, A; Forner-Navarro, L; Prez-Gonzlez, A; Snchez-Marn, F T

    2007-02-01

    The aim of this study was to test the following hypothesis: biomechanical performance (fracture strength and stress distribution) of restored teeth is less sensitive to post diameter and post length when using glass fibre posts than when using stainless steel posts. First, an experimental fracture strength test was performed on 80 extracted human maxillary central incisors. Teeth were decoronated, treated endodontically and restored (40 with glass fibre posts and 40 with stainless steel posts), and the length and diameter of the posts varied uniformly. Failure loads were recorded and results were compared using an ancova analysis. Secondly, the finite element technique was used to develop a model of the restored tooth. The post diameter had a significant effect on the biomechanical performance of teeth restored with stainless steel posts. Lower failure loads were found as post diameter increased. However, the post diameter of those teeth restored with glass fibre posts, and the post length for both post systems under consideration, did not affect the biomechanical performance of restored teeth to a significant degree. The stress distributions predicted by the developed model corroborated these findings, confirmed the assumed hypothesis, and permitted the proposal of the use of glass fibre posts to achieve a restorative technique that is less sensitive to post dimensions, and thus more robust. PMID:17244237

  17. Premolar transplantation in a patient with solitary median maxillary central incisor syndrome.

    PubMed

    Pseiner, Bernhard C

    2014-12-01

    This case report describes the orthodontic treatment of an 11-year-old girl with solitary median maxillary central incisor syndrome, a presumed microform of holoprosencephaly. Because both second premolars were missing in the maxilla, deciduous molar extraction and orthodontic space opening were performed, moving the solitary median maxillary central incisor electively off-center. A mandibular second premolar was transplanted to replace the missing incisor. The resulting spaces could be orthodontically closed in both arches. Prosthodontic reshaping of the transplanted tooth after debonding completed the dental treatment. PMID:25432260

  18. Triple-X syndrome accompanied by single maxillary central incisor: case report.

    PubMed

    Miura, M; Kato, N; Kojima, H; Oguchi, H

    1993-01-01

    Facial, oral, and dental findings of an 11-year-old girl with XXX syndrome are reported. Clinical examination reveals midfacial hypoplasia, congenital absence of teeth, and solitary maxillary central incisors both in primary and permanent dentitions. PMID:8378162

  19. Correction of a severely rotated maxillary central incisor with the Whip device.

    PubMed

    Bayani, Shahin; Khoramian, Somayeh

    2011-01-01

    The following case report presents an appliance named Whip device used for the correction of severe rotations of anterior teeth in pre-adolescent patient. A 9-year-old boy with a severe 90 degrees rotation of upper left central incisor was treated with a Whip appliance. After 3 months of treatment, the position of the upper left central incisor was orthodontically corrected. PMID:22360076

  20. Movement of an upper central incisor across the midline in a patient with cleft of primary palate.

    PubMed

    Manosudprasit, Montian; Wangsrimongkol, Tasanee; Pisek, Poonsak; Chittiwatanapong, Nisa

    2013-09-01

    Orthodontic treatment for a 10-years-old girl, with repaired bilateral cleft lip and left incomplete unilateral alveolar cleft, was performed by moving her right maxillary central incisor across the midline to replace her congenital missing central incisor and then moving the right lateral incisor toward the midline to act as a new central incisor. A malformed supernumerary tooth, positioned between the right central and lateral incisor, was extracted during incisor movement. Significant lip profile improvement was accomplished by maxillary and mandibular anterior teeth retraction into three-premolar extraction spaces. Not only natural functional occlusion, deviated midpalatal suture along the central incisor, and no obvious root resorption were obtained but also narrowing the alveolar bone cleft which was beneficial for bone continuity supporting dental structures, satisfactory results were possible for the patient with primary palate cleft. PMID:24386757

  1. Fracture resistance of upper central incisors restored with different posts and cores

    PubMed Central

    Rezaei Dastjerdi, Maryam; Amirian Chaijan, Kamran

    2015-01-01

    Objectives To determine and compare the fracture resistance of endodontically treated maxillary central incisors restored with different posts and cores. Materials and Methods Forty-eight upper central incisors were randomly divided into four groups: cast post and core (group 1), fiber-reinforced composite (FRC) post and composite core (group 2), composite post and core (group 3), and controls (group 4). Mesio-distal and bucco-lingual dimensions at 7 and 14 mm from the apex were compared to ensure standardization among the groups. Twelve teeth were prepared for crown restoration (group 4). Teeth in other groups were endodontically treated, decoronated at 14 mm from the apex, and prepared for posts and cores. Resin-based materials were used for cementation in groups 1 and 2. In group 3, composite was used directly to fill the post space and for core build-up. All samples were restored by standard metal crowns using glass ionomer cement, mounted at 135° vertical angle, subjected to thermomechanical aging, and then fractured using a universal testing machine. Kruskal-Wallis and Mann-Whitney U tests were used to analyze the data. Results Fracture resistance of the groups was as follows: Control (group 4) > cast post and core (group 1) > fiber post and composite core (group 2) > composite post and core (group 3). All samples in groups 2 and 3 fractured in restorable patterns, whereas most (58%) in group 1 were non-restorable. Conclusions Within the limitations of this study, FRC posts showed acceptable fracture resistance with favorable fracture patterns for reconstruction of upper central incisors. PMID:26295027

  2. Clinical and radiographic evaluation of maxillary central incisors exposure in patients undergoing maxillary advancement

    PubMed Central

    Trento, Guilherme dos Santos; Bernabé, Felipe Bueno Rosettti; da Costa, Delson João; Rebellato, Nelson Luis Barbosa; Klüppel, Leandro Eduardo; Scariot, Rafaela

    2015-01-01

    Abstract Introduction: Patients with dentofacial deformities may undergo orthodontic or orthodontic-surgical treatment. Both modalities can affect esthetics. Objective: This study aims to evaluate clinical and radiographic changes in exposure of maxillary central incisors occurring after orthognathic surgery for maxillary advancement. Methods: A total of 17 patients who underwent orthognathic surgery for maxillary advancement between September, 2010 and July, 2011 were selected. Exposure of maxillary central incisors was evaluated clinically and by lateral cephalograms. Measurements were taken one week before and three months after surgery. Data were paired in terms of sex, age, nasolabial angle, height and thickness of the upper lip, the amount of maxillary advancement, clinical exposure and inclination of maxillary central incisor by statistical tests (CI 95%). Results: After maxillary advancement, incisor clinical exposure had increased even with relaxed lips and under forced smile. Moreover, there was a mean increase of 23.33% revealed by lateral cephalograms. There was an inverse correlation between upper lip thickness and incisors postsurgical exposure revealed by radiographic images (p = 0.002). Conclusions: Significant changes in the exposure of maxillary central incisors occur after maxillary advancement, under the influence of some factors, especially lip thickness. PMID:26691970

  3. Camouflage treatment for class III malocclusion combined with traction of an impacted maxillary central incisor.

    PubMed

    Closs, Luciane Quadrado; Mundstock, Karina Santos; Ribeiro, Darlene Santos; Reston, Eduardo Galia; Silva, Aurelício Novaes

    2010-01-01

    This case report describes the treatment of a patient with an unerupted maxillary left central incisor, class III malocclusion with crossbite of the maxillary posterior teeth and lateral open bite. Treatment consisted of rapid maxillary expansion followed by anterior space opening, maxillary protraction and traction of the unerupted teeth with a light force system. Favorable results were obtained in terms of correcting incisor position and class III malocclusion. The results achieved remained stable throughout a 4-year retention period. PMID:20819408

  4. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report

    PubMed Central

    Nuvvula, Sivakumar

    2013-01-01

    ABSTRACT Maxillary incisors are the most frequently injured teeth in the primary and permanent dentition. Stage of adolescence show a significant number of dental injuries as they engage in contact sports. Children with accident prone profile, i.e. class II division I or class I type II malocclusion are more prone for injuries because of the proclined maxillary incisors. Supernumerary teeth are those that are additional to the normal complement. They occur in single or multiple, unilateral or bilateral in either of the jaws. This paper reports the presence of an inverted supernumerary tooth in the right maxillary central incisor region with trauma involving both maxillary central incisors and also the management of the supernumerary tooth and traumatized teeth in a 14-year-old boy. How to cite this article: Pavuluri C, Nuvvula S. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report. Int J Clin Pediatr Dent 2013;6(1):30-32. PMID:25206184

  5. An unusual case of compound odontome associated with maxillary impacted central incisor.

    PubMed

    Khan, Nadia; Shrivastava, Neha; Shrivastava, Tarun Vijay; Samadi, Fahad Mansoor

    2014-01-01

    Odontomas are the most common type of odontogenic tumor occurring within the jaws and are frequently associated with the retained deciduous teeth interfering with the eruption of permanent teeth. Compound odontomas are usually diagnosed in the anterior portion of the jaws and resemble tooth-like structure. These are usually asymptomatic. Complex odontomas are normally diagnosed in the posterior part of the jaws and consist of a disorganized mass with no morphologic resemblance to a tooth. The present case report of a 16-year-old female is a typical case of compound odontoma in the maxillary anterior region associated with retained deciduous incisor, which also resulted in failure of eruption of the permanent maxillary right central incisor. An intraoral periapical radiograph revealed the presence of a radio-opaque tooth-like structure in the apical region of retained deciduous incisor and an impacted permanent right central incisor whose path of eruption was impeded by the structure. Treatment included the surgical removal of the lesion followed by orthodontic extrusion of the impacted incisor. Follow-up was done for one 1 year and no recurrence was seen. PMID:25937733

  6. An unusual case of compound odontome associated with maxillary impacted central incisor

    PubMed Central

    Khan, Nadia; Shrivastava, Neha; Shrivastava, Tarun Vijay; Samadi, Fahad Mansoor

    2014-01-01

    Odontomas are the most common type of odontogenic tumor occurring within the jaws and are frequently associated with the retained deciduous teeth interfering with the eruption of permanent teeth. Compound odontomas are usually diagnosed in the anterior portion of the jaws and resemble tooth-like structure. These are usually asymptomatic. Complex odontomas are normally diagnosed in the posterior part of the jaws and consist of a disorganized mass with no morphologic resemblance to a tooth. The present case report of a 16-year-old female is a typical case of compound odontoma in the maxillary anterior region associated with retained deciduous incisor, which also resulted in failure of eruption of the permanent maxillary right central incisor. An intraoral periapical radiograph revealed the presence of a radio-opaque tooth-like structure in the apical region of retained deciduous incisor and an impacted permanent right central incisor whose path of eruption was impeded by the structure. Treatment included the surgical removal of the lesion followed by orthodontic extrusion of the impacted incisor. Follow-up was done for one 1 year and no recurrence was seen. PMID:25937733

  7. A new computational method for automatic dental measurement: The case of maxillary central incisor.

    PubMed

    Di Angelo, L; Di Stefano, P; Bernardi, S; Continenza, M A

    2016-03-01

    This paper proposes a new automatic approach to determine the accurate measure of human teeth. The aim of the proposed computer based method is to reduce inaccuracy of measurement with respect to traditional approaches. Starting from a 3D model of the teeth which is obtained from 3D scanning, the method algorithmically evaluates the most important dimensional features detectable in central incisors. For this purpose, specific rules are put forward and implemented in original software with a view to identifying repere points, from which to detect dimensional features both unambiguously and accurately. The automatic method which is proposed here is verified by means of the analysis of real teeth and is then compared with the current state-of-the-art methods for teeth measurement. PMID:26851728

  8. A Global Numerical analysis of the "central incisor/local maxillary bone" system using a meshless method.

    PubMed

    Moreira, S F; Belinha, J; Dinis, L M J S; Jorge, R M Natal

    2014-09-01

    In this work the maxillary central incisor is numerically analysed with an advance discretization technique--Natural Neighbour Radial Point Interpolation Method (NNRPIM). The NNRPIM permits to organically determine the nodal connectivity, which is essential to construct the interpolation functions. The NNRPIM procedure, based uniquely in the computational nodal mesh discretizing the problem domain, allows to obtain autonomously the required integration mesh, permitting to numerically integrate the differential equations ruling the studied physical phenomenon. A numerical analysis of a tooth structure using a meshless method is presented for the first time. A two-dimensional model of the maxillary central incisor, based on the clinical literature, is established and two distinct analyses are performed. First, a complete elasto-static analysis of the incisor/maxillary structure using the NNRPIM is evaluated and then a non-linear iterative bone tissue remodelling analysis of the maxillary bone, surrounding the central incisive, is performed. The obtained NNRPIM solutions are compared with other numerical methods solutions available in the literature and with clinical cases. The results show that the NNRPIM is a suitable numerical method to analyse numerically dental biomechanics problems. PMID:25831859

  9. Treatment of severe rotations of maxillary central incisors with whip appliance: Report of three cases.

    PubMed

    Parisay, Iman; Boskabady, Marzie; Abdollahi, Mojtaba; Sufiani, Mostafa

    2014-01-01

    The routine treatment for rotated maxillary incisor is a fixed appliance, but in some instance the use of this method is impossible. In addition, in only limited cases of rotation, removable appliance is applicable. In this study, the use of a semi-removable appliance is presented, which has some benefits over the other methods. In this study, the corrections of about 70-90° rotation of the maxillary central incisors in different phases of mixed dentition were performed in three patients using whip appliance. This method was performed using a simple removable appliance such as Hawley appliance and whip spring that forced the couple to derotate the tooth. In all cases, treatment was successfully completed in relative short duration. Whip appliance can be recommended as an effective method to correct rotation of maxillary incisor in mixed dentition with several advantages like rapid correction. PMID:24688574

  10. Surgical management of iatrogenic perforation in maxillary central incisor using mineral trioxide aggregate

    PubMed Central

    Nagpal, Rajni; Manuja, Naveen; Pandit, I K; Rallan, Mandeep

    2013-01-01

    Root perforations are undesired complications of endodontic treatment. The repair of root perforation can be accomplished using different materials and techniques. Mineral trioxide aggregate (MTA) is widely used to seal perforations because of its biocompatibility and sealability. This article describes a case report where an iatrogenic root perforation was repaired successfully with MTA in maxillary right central incisor of a 13-year-old boy. PMID:23845686

  11. Orthodontic-restorative treatment as an option for biologic replacement of a maxillary central incisor: 5-year follow-up.

    PubMed

    Rizzatto, Susana Maria Deon; Closs, Luciane Quadrado; Freitas, Maria Perpétua Mota; Rizzatto, Laura Escobar

    2012-09-01

    The maxillary central incisor is the tooth most often affected by trauma, especially in the age range of 7 to 10 years, when high-impact sports are prevalent. The options for conservative treatment should be prioritized in these patients, aiming to achieve a biologic response that might provide continuity of growth of the alveolus, to provide functional and esthetic development of the affected region. This case report describes a patient with a history of trauma during the deciduous dentition with consequent intrusion, root dilaceration, and retention of the maxillary left central incisor. The treatment involved extraction of the traumatized tooth and mesial movement of the lateral incisor and posterior segments. PMID:22920706

  12. Clinical Management of Mid-Root Fracture in Maxillary Central Incisors: Case Reports

    PubMed Central

    Parekh, Deepak J; Sathyanarayanan, Ramarao; Manjunath, Mangala Tiptur

    2010-01-01

    Management of mid-root fractures presents a formidable challenge for clinicians because of the difficulty of achieving a stable reunion of fracture fragments. This article presents two varied treatment options for mid-root fractures. A 15-year-old female reported an impact injury to the maxillary anterior teeth 2 days after its occurrence. Clinically, the maxillary left central incisor was palatally-extruded with a negative vitality response and radiographic evidence of an oblique fracture at the middle third of the root. An endodontic implant was employed which utilized an open technique and has been on follow-up for ten months. A 32-year-old male reported an injury, which resulted in a mobile maxillary right central incisor, three months after its occurrence. Through clinical and radiographic means, a discolored, extruded, and non-vital maxillary right central incisor with an oblique root fracture at the alveolar-crest level was observed. Exploratory surgery was performed; an apical barrier was created with a mineral trioxide aggregate and obturated with gutta percha. The fragments were stabilized with a fiber post and patient has been on follow-up for five months. Short-term follow-up for both of the cases showed promising results both clinically and radiographically. PMID:21404971

  13. Simultaneous Replacement of Maxillary Central Incisors with CEREC Biogeneric Reference Technique: A Case Report

    PubMed Central

    Akgungor, Gokhan; Sen, Deniz; Bal, Eray; Özcan, Mutlu

    2013-01-01

    Biogeneric Reference Technique (BRT) of the CEREC 3D v.3.8 software is an effective technique for single anterior ceramic crowns because it provides computer-controlled match of the tooth form to the contralateral tooth. BRT also enables the fabrication of two or more anterior all-ceramic crowns simultaneously. This clinical report demonstrates the clinical application of BRT for designing and milling two central incisors in one appointment using a single optical impression. After completing the virtual design of the first central incisor, it was copied and a mirror image was created. The second central incisor was designed using this replicated image and therefore a computer-controlled symmetry was obtained. The crowns were milled from monolithic feldspathic ceramic blocks and adhesively luted with dual-cured resin cement following dentin conditioning. At the two-year follow-up appointment, the restorations were intact, no adverse effects were noted, and the resultant appearance was highly satisfactory for the patient. A step-by-step protocol is described from design to cementation of these restorations. PMID:23875091

  14. Genotypic and phenotypic variation in six patients with solitary median maxillary central incisor syndrome.

    PubMed

    Poelmans, Simon; Kawamoto, Tatsuro; Cristofoli, Francesca; Politis, Constantinus; Vermeesch, Joris; Bailleul-Forestier, Isabelle; Hens, Greet; Devriendt, Koenraad; Verdonck, Anna; Carels, Carine

    2015-10-01

    Solitary Median Maxillary Central Incisor occurs in 1 of 50,000 live births. It is the mildest manifestation of the holoprosencephaly spectrum and is genetically heterogeneous. Here we report six patients with solitary median maxillary central incisor, and a range of other phenotypic anomalies with different degrees of severity, varying from mild signs of holoprosencephaly to associated intellectual disability, and with different genetic background. Using array comparative genomic hybridization, pathogenic copy number variants were found in three of the six patients. Two patients had a deletion at the 18p11 chromosomal region that includes TGIF1 while the other patient had a deletion at 7q36, including the SHH gene. In one patient, a mutation in SIX3 was detected with exome sequencing, while in the two remaining patients all known holoprosencephaly genes were excluded using multiplex ligation-dependent probe amplification and sequencing, and remain unsolved. One of the two latter patients had isolated solitary median maxillary central incisor without other visible dentofacial anomalies, while the other had clinical features not part of the known holoprosencephaly spectrum. PMID:26080100

  15. Management of a Central Incisor with Horizontal Root Fracture for Esthetic and Functional Rehabilitation.

    PubMed

    Jepsen, Karin; Schneider, Eva; Dommisch, Henrik; Jepsen, Søren

    2016-01-01

    Severely traumatized incisors in young adults are a very common problem, and one that is difficult to treat because healing of these teeth is not always predictable and implant placement has to be delayed until adulthood. This case report of a horizontal root fracture in an avulsed central incisor illustrates the ability to maintain crucial tooth structure. A lateral socket augmentation procedure after extraction of a root fragment combined with an endodontic and regenerative periodontal treatment approach could preserve natural esthetics and function, which are directly related to quality of life. The preservation of alveolar bone volume following partial root removal will eventually facilitate later placement of a dental implant with an improved esthetic and functional prosthodontic result in a patient with a high-risk esthetic profile. PMID:26697554

  16. Morphometric analysis of pulp size in maxillary permanent central incisors correlated with age: An indirect digital study

    PubMed Central

    Ravindra, S. V.; Mamatha, G. P.; Sunita, J. D.; Balappanavar, Aswini Y.; Sardana, Varun

    2015-01-01

    Context: Teeth are hardest part of the body and are least affected by the taphonomic process. They are considered as one of the reliable methods of identification of a person in forensic sciences. Aim: The aim of the following study is to establish morphometeric measurements by AutoCad 2009 (Autodesk, Inc) of permanent maxillary central incisors in different age groups of Udaipur population. Setting and Design: Hospital-based descriptive cross-sectional study carried out in Udaipur. Materials and Methods: A study was carried out on 308 subjects of both genders with the age range of 9-68 years. Standardized intra-oral radiographs were made by paralleling technique and processed. The radiographs were scanned and the obtained images were standardized to the actual size of radiographic film. This was followed by measuring them using software AutoCad 2009. Statistical Analysis Used: F-test, post-hoc test, Pearson's correlation test. Results: For left maxillary central incisor, the total pulp area was found to be of 38.41 ± 12.88 mm and 14.32 ± 7.04 mm respectively. For right maxillary central incisor, the total pulp size was 38.39 ± 14.95 mm and 12.35 ± 5 mm respectively. Males (32.50, 32.87 mm2) had more pulp area when compared with females (28.82, 30.05 mm2). Conclusion: There was a decrease in total pulp area with increasing age which may be attributed to secondary dentin formation. PMID:26816461

  17. The non-vital discolored central incisor dilemma.

    PubMed

    Schlichting, Lus Henrique; Stanley, Kyle; Magne, Michel; Magne, Pascal

    2015-01-01

    The restoration of anterior teeth is frequently a demanding mission. Patients generally have high expectations for the anterior region, which makes the emotional side of treatment especially important. When this involves discolored endodontically treated teeth, consensus can hardly ever be found as to the chosen approach. Bleaching with direct composites is undoubtedly the most conservative choice for these cases. However, this may require more maintenance (touch-up bleaching and repairs) in the long term, which is an important issue for adult patients. On the other hand, bonded porcelain veneers represent a more 'high-end' option, as they recover the original biomechanics of the intact tooth, allow an optimal masking of the substrate, remain stable, and have a reasonable biological cost when compared to full-coverage crowns. This strategy is explained in this article and documented with a clinical case. We describe treatment planning based on the biomimetic concept, taking into consideration what is possible with current materials and techniques when combined with the patient's particular needs, including the introduction of an innovative step during dentin sealing--the microsuction. The laboratory work was totally accomplished by 'teledentistry', with no direct contact between the dental technologist and the patient. PMID:26794051

  18. Dental Items of Interest: The Case of Delphic Sibyl by Michelangelo: Solitary Median Maxillary Central Incisor or Mesiodens.

    PubMed

    Perciaccante, Antonio; Coralli, Alessia

    2015-01-01

    A case of an anomaly in the maxillary dental arch on "Delphic Sibyl," a fresco by Michelangelo is reported. An accurate analysis of this fresco shows a single incisor tooth is present precisely in the midline. We hypothesize that it may be a case of solitary median maxillary central incisor (SMMCI) and discuss the differential diagnosis with another similar anomaly--the mesiodens. PMID:26930847

  19. Rare Root Morphology of a Maxillary Central Incisor Associated With Gingival Hyperplasia: An Endodontic Case Report.

    PubMed

    Monea, Monica; Moldovan, Cosmin

    2016-05-01

    Dilaceration is a developmental disturbance characterized by the angulation of the crown or root of a permanent tooth, which is often related to trauma of primary dentition. We report a case of a dilacerated root in a maxillary central incisor associated with gingival hyperplasia in a patient under fixed orthodontic treatment, a combination of pathological conditions that had never been mentioned before in the scientific literature.A 10-year-old female patient presented to the Department of Odontology and Oral Pathology with tenderness to palpation and bleeding from the oral aspect of the central incisor, alerted by the proliferation of the gingiva. During clinical examination, the palpation performed with a dental probe revealed a carious lesion with dental pulp exposure on the distal aspect of right central incisor and the presence of a sessile mass of inflamed gingival tissue that proliferated inside the defect. On the preoperative radiograph a dilacerated root canal was noted, without periapical bone resorption.The main diagnosis was irreversible pulpitis and gingival hyperplasia and the treatment option was surgical removal of the inflamed tissue with histopathological examination and root canal treatment. Successful endodontic treatment with a good prognosis was recorded.The measurement of the root curvature proved to be extremely helpful in choosing the right endodontic technique and made the treatment easier than expected. An important observation was that, despite the rare clinical and radiographic aspect of this dilacerated tooth, the endodontic treatment proved to be relatively easy to perform and, therefore, the prognosis was considered favorable. PMID:27149498

  20. Maturogenesis of Two Maxillary Central Incisors: A Case Report with 10 Years of Follow Up

    PubMed Central

    Ghorbanzadeh, Abdollah

    2015-01-01

    This case report describes the treatment of two immature maxillary central incisors in a 7-year-old female patient. She suffered complicated crown fracture because of trauma, and the root formation was incomplete. White mineral trioxide aggregate (MTA) was selected as the pulp-capping material after cervical pulpotomy to preserve the pulp tissue vitality and achieve maturogenesis. Follow-up evaluations showed successful treatment in terms of preservation of pulp vitality and demonstrated marked continuous physiological root development. During 10 years of follow-up, both teeth were clinically asymptomatic, and radiographic evaluations showed apparent root regeneration with apical root-end closure without pulp or periapical pathosis. PMID:26622286

  1. Finite elements study of the Flexi Post and Flexi Flange post systems in a maxillary central incisor.

    PubMed

    Lewgoy, Hugo Roberto; Youssef, Michel Nicolau; Matson, Maurício Rufaiel; Bocangel, Jorge Antônio Javier Saldivar; Netto, Camillo Anauate; Amore, Ricardo

    2003-01-01

    The use of post and core systems has become an excellent alternative for restoring endodontically treated teeth. The aim of this study was to evaluate the von Mises, maximal compressive and tensile stresses distribution using the Finite Element Method (FEM) on human teeth restored with different post and core systems. The analysis was made on endodontically treated maxillary central incisors. The post systems used in this investigation were the stainless steel or titanium Flexi Post/Flexi Flange. Composite resin was used as core material and resin cement was the cement material of choice to seat a full porcelain crown. The bi-dimensional mathematical model was created from pictures taken from an intact human maxillary central incisor and prefabricated posts. This image was transferred to a personal computer in the MSC/Nastran 4.5 software. A static and linear analysis treatment was performed when a 45 load of 100 N was applied on the lingual surface of the tooth. Based on the results obtained, it can be concluded that the post design and its material can alter the stress pattern distribution. PMID:14569354

  2. Periodontal characteristics in individuals with varying form of the upper central incisors.

    PubMed

    Olsson, M; Lindhe, J

    1991-01-01

    It has been suggested that the variation in the morphology of the human periodontium may be related to the shape and form of the teeth. Furthermore, the severity of symptoms of periodontal disease have been proposed to differ among these various morphologic entities or "biotypes". The aim of the present study was (i) to identify individuals with markedly different crown forms and (ii) to determine probing pocket depth, probing attachment level and amount of gingival recession that had occurred at different teeth and tooth surfaces in such individuals. Clinical photographs of the maxillary incisor tooth region of 113 subjects who had been recruited for a long-term study on periodontal disease were available. The length (CL) and width (CW) of the crowns were determined and the CW/CL ratio was calculated for each tooth. 10% in each tail, 11 subjects in each group, were arbitrarily chosen as having either a long-narrow (N) or a short-wide (W) form of the central incisors. The probing pocket depth, probing attachment level and gingival recession data available from all subjects and subjects in groups W and N were compared and analyzed using the Student t-test and multiple regression analysis. The result from the analyses demonstrated that: (1) subjects with a long-narrow form of the upper central incisors had experienced more recession of the gingival margin at buccal surfaces than subjects who had a short-wide tooth form; (2) there was a significant influence of the CW/CL-ratio on the probing attachment level (p less than 0.05) and the amount of gingival recession (p less than 0.01) on buccal tooth surfaces.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2045523

  3. Stress Analysis of a Maxillary Central Incisor Restored with Different Posts

    PubMed Central

    Adanir, Necdet; Belli, Sema

    2007-01-01

    Objectives To evaluate the effects of different post materials on the stress distribution in an endodontically treated maxillary incisor. Materials and Methods A pseudo 3-dimensional finite element model was created in a labiolingual cross-sectional view of a maxillary central incisor and modified according to five posts with different physical properties consisting stainless steel, titanium, gold alloy, glass fiber (Snowpost), and carbon fiber (Composipost). A 200 N force was then applied from two different directions; a) vertical load on the incisal edge, b) 45 degree diagonal load above the cingulum location. Stress distribution and values were then calculated by considering the pseudo three dimensional von Mises stress criteria. Results Under two loading conditions, post made of steel showed greatest stress concentration at the post/dentin interface followed by titanium, gold alloy, Snowpost and Composipost. However, Composipost, which elastic modulus was closer to the dentin, produced highest stress values at 1/3 cervical area. Conclusions Within the limitation of this simulated mechanical analysis, we can conclude that the physical characteristics of posts were important on stress distributions in post and core applications. Glass fiber post revealed more balanced stress distribution under functional forces. PMID:19212479

  4. Management of a Two-rooted Maxillary Central Incisor Using Cone-beam Computed Tomography: Importance of Three-dimensional Imaging

    PubMed Central

    Kumar Gupta, Saurabh; Saxena, Payal; Khetarpal, Shaleen; Solanki, Mishthu

    2015-01-01

    We report a rare case of a two-rooted maxillary central incisor, stressing the importance of three-dimensional imaging in treatment planning and conservative approach of management. Endodontic treatment of this central incisor was carried out with a successful outcome. PMID:26697155

  5. Corono-radicular biological restoration of maxillary central incisors by direct method.

    PubMed

    Aggarwal, Sonia; Sahoo, Sujit Ranjan; Pandharkar, Kartik

    2014-11-01

    This case report refers to the esthetic and functional restorations of extensively damaged maxillary central incisors with dental caries in a 32-year-old woman, with the use of posts and crowns made from natural extracted teeth. Proper restoration of such teeth with the use of natural teeth fragments are known as "biological restoration." Biological restorations can be done by using the fragments of the patients own tooth and if that is not available, tooth fragment can be obtained from an extracted tooth. These biological posts and crowns present a low cost option and an alternative technique for the morphofunctional recovery of extensively damaged teeth. There are limitations with the use of natural extracted teeth (homogenous bonding) for restoration such as the difficulty of finding teeth with a similar color and shape as that of the destroyed element, or patient may refuse to accept a tooth fragment from another patient, which prevents execution of the restoration. PMID:25540666

  6. Management of recurrent fracture of central incisor with internal resorption using light transmitting (luminex) post.

    PubMed

    Hariharan, V S; Nandlal, B; Srilatha, K T

    2010-01-01

    The normal root canal anatomy may be altered in various pathological processes and making it very difficult and at times impossible to achieve ideal obturation by normal methods. Internal resorption is one among them. There are several treatment protocols advised for this pathological condition. A crown-root fracture is defined as a fracture involving enamel, dentin and cementum and accounts for 5% of all traumatic injuries to the permanent dentition. In anterior teeth, these fractures are usually caused by direct trauma and often complicated in fully erupted teeth. In cases where the fracture line extends down along the long axis of the root, extraction of the tooth is indicated. The purpose of this report is to present the use of light transmitting post system to reinforce the crown root fractured maxillary central incisor due to trauma and internal resorption. PMID:21273718

  7. Reattachment of a severely traumatized maxillary central incisor, one-year clinical evaluation: a case report.

    PubMed

    El-Askary, Farid S; Ghalab, Omaima H; Eldemerdash, Fatma H; Ahmed, Ola I R; Fouad, Shaimaa A; Nagy, Mohammed M

    2006-10-01

    Traumatic fracture of anterior teeth is one of the common dilemmas facing the dentist during daily practice. Classical treatment of a fractured tooth involving the pulp includes the use of post and core with or without a crown, or extraction of the remaining part of the fractured tooth and replacement with a three-unit fixed partial denture or an implant. With the improvement of adhesive systems, reattachment of the fractured tooth fragment became possible as a mode of treatment that immediately improves the esthetic quality of the restored tooth. This article presents a clinical technique for the restoration of a fractured maxillary central incisor, by reattaching the labial enamel fragment using a metallic post and resin composite restoration. One-year clinical evaluation revealed successful results for this technique. PMID:17080883

  8. A case of impacted central incisor due to dentigerous cyst associated with impacted compound odontome.

    PubMed

    Jayam, Cheranjeevi; Bandlapalli, Anila; Patel, Nikunj; Choudhary, Rama Shankar Kashinath

    2014-01-01

    Odontomes are hamartomatous growths of odontogenic origin. Odontomes usually do not erupt into oral cavity and can cause several difficulties like swelling, displacement of teeth and adjacent structures, cystic changes and carcinomatous transformation. Odontomes are treated by surgical removal. Dentigerous cysts arise due to accumulation of fluid between reduced enamel epithelium and crown of unerupted tooth. Dentigerous cysts cause several difficulties such as swelling, non-eruption of involved teeth and displacement of adjacent teeth, thus requiring early detection and prompt treatment. Treatment for dentigerous cyst ranges from marsupialisation to enucleation. In children, marsupialisation is more commonly used when compared with enucleation treatment. This study discusses successful treatment of impacted central incisor due to obstruction from dentigerous cyst originating from impacted compound odontome. The paper also throws light into importance to radiography while diagnosing odontome. PMID:24654240

  9. Corono-radicular biological restoration of maxillary central incisors by direct method

    PubMed Central

    Aggarwal, Sonia; Sahoo, Sujit Ranjan; Pandharkar, Kartik

    2014-01-01

    This case report refers to the esthetic and functional restorations of extensively damaged maxillary central incisors with dental caries in a 32-year-old woman, with the use of posts and crowns made from natural extracted teeth. Proper restoration of such teeth with the use of natural teeth fragments are known as “biological restoration.” Biological restorations can be done by using the fragments of the patients own tooth and if that is not available, tooth fragment can be obtained from an extracted tooth. These biological posts and crowns present a low cost option and an alternative technique for the morphofunctional recovery of extensively damaged teeth. There are limitations with the use of natural extracted teeth (homogenous bonding) for restoration such as the difficulty of finding teeth with a similar color and shape as that of the destroyed element, or patient may refuse to accept a tooth fragment from another patient, which prevents execution of the restoration. PMID:25540666

  10. Replacement of Maxillary Permanent Central Incisors Lost Due to Trauma in the Mixed-Dentition.

    PubMed

    Rubel, Barry; Hill, Edward E

    2015-04-01

    Traumatic injuries to anterior teeth in children range from minor chipping to total tooth loss and occur more often in boys than in girls. The treatment of permanent tooth loss in younger patients is complicated by the difficulty of doing restorative procedures which may be influenced by pulpal size, clinical crown height, and a dental profile that is constantly changing. This case report presented a situation involving a 9-year-old boy who had experienced traumatic loss of the maxillary central incisors. Innovative materials coupled with sound principles of removable partial denture design were utilized to fabricate a cast metal removable denture prosthesis to satisfy the esthetic, functional and psychological dental needs of the patient and his parents. PMID:26268010

  11. Biometric analysis of the dental casts of Maasai following traditional extraction of mandibular permanent central incisors and of Kikuyu children.

    PubMed

    Hassanali, J; Amwayi, P

    1993-12-01

    Dental plaster casts of 93 Maasai and 79 Kikuyu children age 12-15 years were analysed. Four biometric measurements were taken of the maxillary and mandibular casts: intercanine distance (C-C), inter-molar distance (M-M), canine arch circumference (C-C ACirc.), and molar arch circumference (M-M ACirc.). Incisor space (IS) was also measured in the mandibular casts. The mean values of all measurements except (M-M) in the mandibular casts were significantly reduced in the Maasai who had permanent central incisors extracted compared to the non-extracted Maasai and the Kikuyu. The mean incisor space in the Maasai with extractions was 6.3 mm compared to 11.7 mm in the non-extracted Maasai group. The extent of reduction of IS, C-C, C-C ACirc. and M-M ACirc. following extractions of the incisors may depend on the mesial drift of lateral incisors, jaw growth and soft tissue influence. The position of the tongue and occlusal relationship of the molars may prevent bucco-lingual movements maintaining a constant M-M. There was no significant difference in the mandibular cast dimensions of the non-extracted Maasai and the Kikuyu. Analysis of the maxillary cast dimensions of the Maasai with extraction, non-extracted Maasai and Kikuyu showed no significant differences suggesting that the extraction of mandibular incisors has no effect on maxillary arch dimensions. The variability in growth of the dento-alveolar complex itself may explain why the dental arch dimensions are similar in the Maasai and Kikuyu despite ethnic differences. There was no significant difference between the male and female dental arch dimensions. PMID:8112417

  12. Surgical management of multiple supernumerary teeth and an impacted maxillary permanent central incisor.

    PubMed

    Rallan, Mandeep; Rallan, Neelakshi Singh; Goswami, Mousumi; Rawat, Kamini

    2013-01-01

    Hyperdontia is the condition of having supernumerary teeth, or teeth which appear in addition to the regular number of teeth. It is a developmental anomaly and has been argued to arise from multiple aetiologies. The most common site is the maxillary incisor region; but the prevalence of more than three teeth supernumerary tooth is less than 1%. A case of 13 year male patient is reported with a multiple impacted supernumerary tooth in maxillary anterior region hindering the eruption of right permanent central incisor. The supernumerary tooth was treated via surgical approach followed by an interim prosthesis for permanent central incisor which later on erupted in due course of time. Background Supernumerary teeth may be defined as any teeth or tooth substance in excess of the usual configuration of 20 deciduous and 32 permanent teeth. The presence of supernumerary teeth in the premaxillary region often poses unique diagnostic and managerial concerns for the practitioner. Rarely is the surplus number compensated by an absence or deficiency of other teeth. Therefore, the dysfunctional nature of supernumerary teeth and their ability to create a variety of pathological disturbances in the normal eruption and position of adjacent teeth warrants their early detection and prudent management. Approximately 76-86% of cases represent single-tooth hyperdontia, with two supernumerary teeth noted in 12-23% and three or more extra teeth noted in less than 1% of cases. Multiple supernumerary teeth are also associated with many syndromes like cleidocranial dysplasia and Gardner’s syndrome etc. However, it is rare to find multiple supernumeraries in individuals with no other associated disease or syndrome. In such cases, the maxillary anterior region is the common site of occurrence. The exact aetiology is not clearly understood. The supernumerary teeth result from any disturbance in the initiation and proliferation stages of odontogenesis. There are several theories regarding the development of a supernumerary tooth-phylogenetic reversion (atavism) theory, dichotomy of tooth germ theory and hyperactivity of the dental lamina. The latter being the most accepted theory, states that the remnants of dental lamina or palatal offshoots of active dental lamina are induced to develop into an extra tooth bud, which results in the formation of a supernumerary tooth. Genetics is also considered to contribute to the development of supernumerary teeth, as these have been diagnosed in twins, siblings and sequential generations of a family. Classification of supernumerary teeth may be on the basis of position or form. Positional variations include mesiodens, paramolars, distomolars and parapremolars. Variations in form consist of conical types, tuberculate types, supplemental teeth and odontomes. Supernumerary teeth may, therefore, vary from a simple odontome, through a conical or tuberculate tooth to a supplemental tooth which closely resembles a normal tooth. Also, the site and number of supernumeraries can vary greatly. This report presents a case of a non-syndromic male patient with multiple supernumerary teeth and a permanent impacted tooth in the maxillary anterior region. PMID:23704467

  13. Solitary median maxillary central incisor in association with hemifacial microsomia: A rare case report and review of literature

    PubMed Central

    Utreja, Ashok; Zahid, Syed Naved; Gupta, Richa

    2011-01-01

    Solitary median maxillary central incisor (SMMCI) is a rare dental anomaly. It is estimated to occur in 1:50,000 live births. The SMMCI tooth differs from the normal central incisor in that the crown form is symmetric and it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Presence of SMMCI with hemifacial microsomia (HFM) is a very rare clinical condition. We report a case of HFM in a male of Indian origin who presented with SMMCI in both primary and permanent dentitions. The association of HFM with SMMCI may be due to defective development of neural crest cells and/or lack of space in maxilla. PMID:22346174

  14. Finite element analysis of stress concentration in three popular brands of fiber posts systems used for maxillary central incisor teeth

    PubMed Central

    Aggarwal, Shalini; Garg, Vaibhav

    2011-01-01

    Aims and Objectives: To study the stress concentrations in endodontically treated maxillary central incisor teeth restored with 3 different fiber post systems subjected to various oblique occlusal loads. Materials and Methods: FEM analysis was used to analyze stress concentrations generated in maxillary anterior teeth. Computer aided designing was used to create a 2-D model of an upper central incisor. Post systems analyzed were the DT Light Post (RDT, Bisco), Luscent Anchor (Dentatus) & RelyX (3M-ESPE). The entire design assembly was subjected to analysis by ANSYS for oblique loading forces of 25N, 80N & 125 N Results: The resultant data showed that the RelyX generated the least amount of stress concentration. Conclusions: Minimal stress buildups contribute to the longevity of the restorations. Thus RelyX by virtue of judicious stress distribution is the better option for restoration of grossly decayed teeth. PMID:22025836

  15. An in vitro study of the effect endodontic access preparation has upon the retention of porcelain fused to metal crowns of maxillary central incisors.

    PubMed

    McMullen, A F; Himel, V T; Sarkar, N K

    1989-04-01

    Endodontic therapy often requires cutting access preparations through existing restorations. The purpose of this study was to determine whether endodontic access preparation affected the retention of porcelain fused to metal crowns of maxillary central incisors. Retentive forces required to displace porcelain fused to metal crowns of maxillary central incisors were measured using an Instron constant displacement rate testing machine. Using a paired t test analysis, a significant difference was found between crown retention before and after endodontic access preparation. PMID:2691625

  16. Accelerated Osteogenic Orthodontics™ for retreatment of a patient with diminished root length and absence of the maxillary central incisor

    PubMed Central

    Montesinos F, Armando; Linares T, Silvana; Pérez-Gasque B, Marisol

    2015-01-01

    An 18-year-old female patient visited a university orthodontics department with a chief complaint of an unesthetic appearance of her teeth, including a protruded upper central incisor and unsatisfactory results from previous orthodontic treatment. Pretreatment records showed a Class II skeletal and dental relation with proclined upper and lower incisors, replacement of an absent upper left central incisor with the left upper cuspid, presence of the upper left deciduous cuspid, mild crowding, and 4 mm of overbite and overjet. The panoramic radiograph showed shortened roots of multiple teeth. Accelerated Osteogenic Orthodontics™ (AOO™) was recommended as an approach to reduce the treatment time and the risk of further root shortening. Despite being more expensive and requiring a surgical procedure, this treatment option was very attractive to the patient. The overall treatment time was 14 months. Facial balance was improved, and good occlusal relationships were achieved from the functional and esthetic perspectives. In conclusion, surgically facilitated orthodontics (specifically, AOO™) is an efficient and safe therapeutic tool for treating or retreating orthodontic patients with diminished root length. PMID:26644760

  17. Impacted stapler pin in fractured maxillary central incisor with open apex: Advanced endodontic management using biodentine as innovative apical matrix.

    PubMed

    Sharma, Vikram; Tanwar, Renu; Gupta, Vidhi; Mehta, Palkin

    2015-01-01

    The presence of foreign objects in the pulp chamber of fractured permanent teeth is a rare phenomenon and often diagnosed accidently .These foreign bodies are most commonly self inflicted by young patients and remain impacted within the pulp canal thereby acting as potential source of infection and painful conditions1. In the present case report, we present successful endodontic management of stapler pin lodged in fractured maxillary central incisor with challenge of open apex in young patient using biodentine as a novel apical matrix. PMID:26888245

  18. Complete root resorption of an upper central incisor due to ectopic eruption of canine in a deaf-mute child.

    PubMed

    Morisaki, I; Hashida, S; Mihara, J; Takagaki, M; Sobue, S

    1990-12-01

    Unilateral complete root resorption of the permanent central incisor was experienced in a boy with deaf and dumb. Transposition of tooth germ or abnormally directed eruption of the canine caused not only an entire root but a part of enamel resorption. The patient was diagnosed clinically and radiographically as an ectopic eruption of the right maxillary upper canine and then treatments were provided to improve esthetic and functional conditions in terms of eruption guidance. It should be emphasized that the early diagnosis and the subsequent eruption guidance is essential in the patient with these kinds of eruption disorder of the mixed dentition. PMID:2151819

  19. Stress distribution in the cervical region of an upper central incisor in a 3D finite element model.

    PubMed

    Poiate, Isis Andréa Venturini Pola; Vasconcellos, Adalberto Bastos de; Poiate Junior, Edgard; Dias, Kátia Regina Hostílio Cervantes

    2009-01-01

    The aim of this study was to evaluate the stress distribution in the cervical region of a sound upper central incisor in two clinical situations, standard and maximum masticatory forces, by means of a 3D model with the highest possible level of fidelity to the anatomic dimensions. Two models with 331,887 linear tetrahedral elements that represent a sound upper central incisor with periodontal ligament, cortical and trabecular bones were loaded at 45 masculine in relation to the tooth's long axis. All structures were considered to be homogeneous and isotropic, with the exception of the enamel (anisotropic). A standard masticatory force (100 N) was simulated on one of the models, while on the other one a maximum masticatory force was simulated (235.9 N). The software used were: PATRAN for pre- and post-processing and Nastran for processing. In the cementoenamel junction area, tensile forces reached 14.7 MPa in the 100 N model, and 40.2 MPa in the 235.9 N model, exceeding the enamel's tensile strength (16.7 MPa). The fact that the stress concentration in the amelodentinal junction exceeded the enamel's tensile strength under simulated conditions of maximum masticatory force suggests the possibility of the occurrence of non-carious cervical lesions such as abfractions. PMID:19684951

  20. Changes in force associated with the amount of aligner activation and lingual bodily movement of the maxillary central incisor

    PubMed Central

    Li, Xiaowei; Ren, Chaochao; Wang, Zheyao; Zhao, Pai; Wang, Hongmei

    2016-01-01

    Objective The purposes of this study were to measure the orthodontic forces generated by thermoplastic aligners and investigate the possible influences of different activations for lingual bodily movements on orthodontic forces, and their attenuation. Methods Thermoplastic material of 1.0-mm in thickness was used to manufacture aligners for 0.2, 0.3, 0.4, 0.5, and 0.6 mm activations for lingual bodily movements of the maxillary central incisor. The orthodontic force in the lingual direction delivered by the thermoplastic aligners was measured using a micro-stress sensor system for the invisible orthodontic technique, and was monitored for 2 weeks. Results Orthodontic force increased with the amount of activation of the aligner in the initial measurements. The attenuation speed in the 0.6 mm group was faster than that of the other groups (p < 0.05). All aligners demonstrated rapid relaxation in the first 8 hours, which then decreased slowly and plateaued on day 4 or 5. Conclusions The amount of activation had a substantial influence on the orthodontic force imparted by the aligners. The results suggest that the activation of lingual bodily movement of the maxillary central incisor should not exceed 0.5 mm. The initial 4 or 5 days is important with respect to orthodontic treatment incorporating an aligner. PMID:27019820

  1. A Fused Maxillary Central Incisor and Its Multidisciplinary Treatment: An 18-Year Follow-Up

    PubMed Central

    Brunet-Llobet, Llus; Lahor-Soler, Eduard; Cahuana, Abel

    2014-01-01

    Fused teeth may cause aesthetic, spacing, periodontal, eruption, and caries problems. The present case report describes a 7-year-old boy patient with a chief complaint of unerupted maxillary incisor. Radiographic examination indicated a fused tooth which had two fused roots but two independent root canals. A complex management of a fused tooth is really difficult to standardize. In this case an orthodontic, endodontic, and surgical treatment (intentional replantation) allowed the tooth to be retained until 18 years following intervention. Maintenance of the root and alveolar bone in young adults at least until full skeletal maturation should be the main treatment objective. PMID:24738034

  2. Interdisciplinary rehabilitation of a root-fractured maxillary central incisor: A 12-year follow-up case report

    PubMed Central

    Incerti Parenti, Serena; Ciocci, Maurizio; Checchi, Luigi

    2014-01-01

    Single-tooth implantation has become a common treatment solution for replacement of a root-fractured maxillary incisor in adults, but the long-term esthetic results can be unfavorable due to progressive marginal bone loss, resulting in gingival recession. In this case report, a maxillary central incisor with a root fracture in its apical one-third was orthodontically extruded and extracted in a 21-year-old female. Implant surgery was performed after a 3-month healing period, and the final crown was placed about 12 months after extraction. After 12 years, favorable osseous and gingival architectures were visible with adequate bone height and thickness at the buccal cortical plate, and no gingival recession was seen around the implant-supported crown. Although modern dentistry has been shifting toward simplified, clinical procedures and shorter treatment times, both general dentists and orthodontists should be aware of the possible long-term esthetic advantages of orthodontic extrusion of hopelessly fractured teeth for highly esthetically demanding areas and should educate and motivate patients regarding the choice of this treatment solution, if necessary. PMID:25133136

  3. Adhesive reattachment rehabilitating a nonvital central incisor with a complicated crown-root fracture: 1-year follow-up.

    PubMed

    Monteiro, Marcilio Jorge Fernandes; Cohen-Carneiro, Flavia; Tino, Giselle Desideri; Franco Marques, Andre Augusto; Pontes, Danielson Guedes

    2015-01-01

    Dental trauma requires immediate treatment. However, some conventional treatments (such as an implant and/or partial fixed denture) will not always be immediately possible, due to the patient's age (mainly in pediatric cases) or lack of immediate financial resources. In such situations, the technique of adhesive reattachment plays an important role as a treatment option in the interim. This case report describes the use of adhesive fragment reattachment in the rehabilitation of a maxillary central incisor with a complicated crown-root fracture. A 1-year follow-up affirmed that the adhesive reattachment efficiently resolved the crown-root fracture, allowing for the retention of the tooth structure. This more conservative multidisciplinary approach restored function, esthetics, and self-esteem to the patient, while preserving all bone and gingival architecture for future implant treatment. PMID:26147175

  4. Preservative management of traumatized maxillary central incisor using fiber reinforced composite and mineral trioxide aggregate: Report of a case.

    PubMed

    Surapaneni, Sai Kalyan; Chandki, Rita

    2015-08-01

    The myriads of technological advancements in dentistry in last two decades have led to a dramatic shift from conventional invasive procedures to more conservative biomimetic therapies. In this series, management of traumatic dental injuries has taken a big leap in that now it is possible to conserve many of these teeth which were otherwise doomed to extraction. Depending on the extent of injury, esthetic and functional requirements, traumatic dental injuries can be managed by a variety of clinical procedures including composite resin restorations, reattachment of fractured fragment, endodontic therapy with or without post and core or lastly extraction. Reattaching natural tooth structure offers an advantage over the others in that it is instant, provides superior esthetics, preserves the natural tooth structure and is best accepted by the patient. This paper describes the comprehensive management of traumatized maxillary central incisor involving pulp exposure while maintaining pulp vitality and natural appearance of a tooth. PMID:26604608

  5. Preservative management of traumatized maxillary central incisor using fiber reinforced composite and mineral trioxide aggregate: Report of a case

    PubMed Central

    Surapaneni, Sai Kalyan; Chandki, Rita

    2015-01-01

    The myriads of technological advancements in dentistry in last two decades have led to a dramatic shift from conventional invasive procedures to more conservative biomimetic therapies. In this series, management of traumatic dental injuries has taken a big leap in that now it is possible to conserve many of these teeth which were otherwise doomed to extraction. Depending on the extent of injury, esthetic and functional requirements, traumatic dental injuries can be managed by a variety of clinical procedures including composite resin restorations, reattachment of fractured fragment, endodontic therapy with or without post and core or lastly extraction. Reattaching natural tooth structure offers an advantage over the others in that it is instant, provides superior esthetics, preserves the natural tooth structure and is best accepted by the patient. This paper describes the comprehensive management of traumatized maxillary central incisor involving pulp exposure while maintaining pulp vitality and natural appearance of a tooth. PMID:26604608

  6. Orthodontic movement of a maxillary central incisor with a horizontal root fracture treated using an intra-radicular fibre splint

    PubMed Central

    Kapur, Aditi; Utreja, A.; Goyal, A.; Pankaj, P.

    2013-01-01

    This paper reports the case of a 15-year-old boy with a horizontal root fracture in the left maxillary central incisor along with class II division 1 malocclusion for whom a fixed orthodontic treatment was planned. The fracture was present at the junction of apical and middle-third as a result of trauma 2 years back. No splinting was carried out at that time and the tooth was found to be vital, asymptomatic and showed a type-1 repair pattern. An intentional root canal treatment was carried out for placement of an intra-radicular fiber splint, nearly 3 mm beyond the fracture line. Orthodontic treatment was initiated after a month; to which the fractured and splinted tooth responded successfully. This report highlights the successful use of an intra-radicular splint for horizontally fractured tooth requiring orthodontic treatment. PMID:24015026

  7. Approximation and contact of the maxillary central incisor roots with the incisive canal after maximum retraction with temporary anchorage devices: Report of 2 patients.

    PubMed

    Chung, Chooryung J; Choi, Yoon Jeong; Kim, Kyung-Ho

    2015-09-01

    The incisive canal is located on the median plane of the maxilla, posterior to the roots of the central incisor. Although the incisive canal is not considered an anatomic structure that may limit tooth movement, it has recently gained attention regarding the possibilities of surgical invasion and associated complications because of its proximity to the maxillary central incisors. In the 2 illustrated cases, lip protrusion was improved by en-masse bodily retraction of the anterior teeth (>8 mm) using temporary anchorage devices. Three-dimensional cone-beam computed tomography showed that the maxillary incisor roots were approximated to the incisive canal after maximum retraction. One central incisor root was in direct contact with the incisive canal with severe root resorption, but tooth vitality and the overall occlusion were stable in the long term without any sensory dysfunction. The apparent root resorption may be mainly related to the large amounts of anterior retraction and root movement in the 2 patients. However, the anatomic location of the incisive canal and the possibilities of its invasion after tooth movement should be closely monitored when maximum retraction is planned, to prevent potential complications. PMID:26321347

  8. 3D FEA of cemented glass fiber and cast posts with various dental cements in a maxillary central incisor.

    PubMed

    Madfa, Ahmed A; Al-Hamzi, Mohsen A; Al-Sanabani, Fadhel A; Al-Qudaimi, Nasr H; Yue, Xiao-Guang

    2015-01-01

    This study aimed to analyse and compare the stability of two dental posts cemented with four different luting agents by examining their shear stress transfer through the FEM. Eight three-dimensional finite element models of a maxillary central incisor restored with glass fiber and Ni-Cr alloy cast dental posts. Each dental post was luted with zinc phosphate, Panavia resin, super bond C&B resin and glass ionomer materials. Finite element models were constructed and oblique loading of 100 N was applied. The distribution of shear stress was investigated at posts and cement/dentine interfaces using ABAQUS/CAE software. The peak shear stress for glass fiber post models minimized approximately three to four times of those for Ni-Cr alloy cast post models. There was negligible difference in peak of shear stress when various cements were compared, irrespective of post materials. The shear stress had same trend for all cement materials. This study found that the glass fiber dental post reduced the shear stress concentration at interfacial of post and cement/dentine compared to Ni-Cr alloy cast dental post. PMID:26543733

  9. An In Vitro Study on the Effects of Post-Core Design and Ferrule on the Fracture Resistance of Endodontically Treated Maxillary Central Incisors

    PubMed Central

    Sreedevi, S; Sanjeev, R; Raghavan, Rekha; Abraham, Anna; Rajamani, T; Govind, Girish Kumar

    2015-01-01

    Background: Endodontically treated teeth have significantly different physical and mechanical properties compared to vital teeth and are more prone to fracture. The study aims to compare the fracture resistance of endodontically treated teeth with and without post reinforcement, custom cast post-core and prefabricated post with glass ionomer core and to evaluate the ferrule effect on endodontically treated teeth restored with custom cast post-core. Materials and Methods: A total of 40 human maxillary central incisors with similar dimensions devoid of any root caries, restorations, previous endodontic treatment or cracks were selected from a collection of stored extracted teeth. An initial silicone index of each tooth was made. They were treated endodontically and divided into four groups of ten specimens each. Their apical seal was maintained with 4 mm of gutta-percha. Root canal preparation was done and then post core fabrication was done. The prepared specimens were subjected to load testing using a computer coordinated UTM. The fracture load results were then statistically analyzed. One-way ANOVA was followed by paired t-test. Results: 1. Reinforcement of endodontically treated maxillary central incisors with post and core, improved their fracture resistance to be at par with that of endodontically treated maxillary central incisor, with natural crown. 2. The fracture resistance of endodontically treated maxillary central incisors is significantly increased when restored with custom cast post-core and 2 mm ferrule. Conclusion: With 2 mm ferrule, teeth restored with custom cast post-core had a significantly higher fracture resistance than teeth restored with custom cast post-core or prefabricated post and glass ionomer core without ferrule. PMID:26464537

  10. Amalgamation of allogenic bone graft, platelet-rich fibrin gel, and PRF membrane in auto-transplantation of an impacted central incisor

    PubMed Central

    Chaudhary, Zainab; Kumar, Yuvika Raj; Mohanty, Sujata; Khetrapal, Ambica

    2015-01-01

    “Social six” teeth refers to the maxillary incisors and canines that play a vital role in the appearance of an individual and absence of any one of them has a significant psycho-social impact. Hence, early treatment and rehabilitation of the same are extremely important. A multitude of treatment options ranging from orthodontic extrusion, extraction followed by implant placement, fixed partial denture, and auto-transplantation have been advocated. This case report discusses the unique amalgamation of platelet-rich fibrin (PRF), demineralized freeze-dried bone graft with use of PRF membrane during auto-transplantation of an impacted central incisor. The authors have focused on maximum usage of autogenous materials in the most economic and least invasive manner. Furthermore, this amalgamation has been used to provide rehabilitation in the least span of time. PMID:26097366

  11. Amalgamation of allogenic bone graft, platelet-rich fibrin gel, and PRF membrane in auto-transplantation of an impacted central incisor.

    PubMed

    Chaudhary, Zainab; Kumar, Yuvika Raj; Mohanty, Sujata; Khetrapal, Ambica

    2015-01-01

    "Social six" teeth refers to the maxillary incisors and canines that play a vital role in the appearance of an individual and absence of any one of them has a significant psycho-social impact. Hence, early treatment and rehabilitation of the same are extremely important. A multitude of treatment options ranging from orthodontic extrusion, extraction followed by implant placement, fixed partial denture, and auto-transplantation have been advocated. This case report discusses the unique amalgamation of platelet-rich fibrin (PRF), demineralized freeze-dried bone graft with use of PRF membrane during auto-transplantation of an impacted central incisor. The authors have focused on maximum usage of autogenous materials in the most economic and least invasive manner. Furthermore, this amalgamation has been used to provide rehabilitation in the least span of time. PMID:26097366

  12. Neonatal line width in deciduous incisors from Neolithic, mediaeval and modern skeletal samples from north-central Poland.

    PubMed

    Kurek, Marta; Żądzińska, Elżbieta; Sitek, Aneta; Borowska-Strugińska, Beata; Rosset, Iwona; Lorkiewicz, Wiesław

    2016-01-01

    The neonatal line is usually the first accentuated incremental line visible on the enamel. The prenatal environment significantly contributes to the width of the neonatal line, influencing the pace of reaching post-delivery homeostasis by the newborn's organism. Studies of the enamel of the earliest developing deciduous teeth can provide an insight into the prenatal development and the perinatal conditions of children of past human populations, thus being an additional source contributing to consideration of the influence of prenatal and perinatal factors modifying growth processes. The aim of this study was to examine whether the neonatal line, reflecting the conditions of the prenatal and perinatal environment, differed between the Neolithic, the mediaeval and the modern populations from the Kujawy region in north-central Poland. The material consisted of longitudinally ground sections of 57 human deciduous incisors obtained from children aged 1.0-7.5 years representing three archaeological series from Brześć Kujawski site. All teeth were sectioned in the labio-linqual plane using a diamond blade (Buechler IsoMet 1000). Final specimens were observed with the microscope Delta Optical Evolution 300 at 10× and 40× magnifications. For each tooth, linear measurements of the neonatal line width were performed on its labial surface at the three levels from the cemento-enamel junction. No significant difference was found in the mean neonatal line width depending on the tooth type and archaeological site, although the thickest neonatal line characterised children from the Neolithic series. In all analysed series, the neonatal line width was diversified depending on the child's age at death. The value of Spearman's rank correlation coefficient calculated for the correlation between the child's age at death and the neonatal line width was statistically significant. A clear increase in the width of the neonatal line was thus observed along with a decrease in the child's age at death. PMID:25800876

  13. Effect of labiolingual inclination of a maxillary central incisor and surrounding alveolar bone loss on periodontal stress: A finite element analysis

    PubMed Central

    Choi, Sung-Hwan; Kim, Young-Hoon; Lee, Kee-Joon

    2016-01-01

    Objective The aim of this study was to investigate whether labial tooth inclination and alveolar bone loss affect the moment per unit of force (Mt/F) in controlled tipping and consequent stresses on the periodontal ligament (PDL). Methods Three-dimensional models (n = 20) of maxillary central incisors were created with different labial inclinations (5°, 10°, 15°, and 20°) and different amounts of alveolar bone loss (0, 2, 4, and 6 mm). The Mt/F necessary for controlled tipping (Mt/Fcont) and the principal stresses on the PDL were calculated for each model separately in a finite element analysis. Results As labial inclination increased, Mt/Fcont and the length of the moment arm decreased. In contrast, increased alveolar bone loss caused increases in Mt/Fcont and the length of the moment arm. When Mt/F was near Mt/Fcont, increases in Mt/F caused compressive stresses to move from a predominantly labial apical region to a palatal apical position, and tensile stresses in the labial area moved from a cervical position to a mid-root position. Although controlled tipping was applied to the incisors, increases in alveolar bone loss and labial tooth inclination caused increases in maximum compressive and tensile stresses at the root apices. Conclusions Increases in alveolar bone loss and labial tooth inclination caused increases in stresses that might cause root resorption at the root apex, despite the application of controlled tipping to the incisors. PMID:27226961

  14. Clinical course and implications of congenital nasal pyriform stenosis and solitary median maxillary central incisor in a newborn: a case report

    PubMed Central

    2014-01-01

    Introduction Congenital nasal pyriform aperture stenosis and solitary median maxillary central incisor are uncommon anomalies and are associated with further malformations. Solitary median maxillary central incisor itself has initially no impact on a childs health, but congenital nasal pyriform aperture stenosis is a potentially life-threatening condition. Case presentation A Caucasian baby boy showed severe dyspnoea and was intubated orotracheally. Multiple anomalies were detected, including urogenital and craniofacial malformations. Computed tomography scans revealed congenital nasal pyriform aperture stenosis with a diameter of 4.9mm and a solitary median maxillary central incisor. A 3.0mm tube was inserted in his left nasal cavity, and the baby was able to breathe sufficiently and spontaneously. The nasal tube was removed after seven days, and the baby was discharged under application of decongestant drops. After seven months, the baby was readmitted with respiratory distress, and surgery was carried out using an intraoral sublabial approach. The stenotic area of the pyriform aperture was widened, and 3.0mm tubes were inserted in both nasal cavities for 10 days. Over a period of six months, no further respiratory distress has occurred. Conclusions The decision to perform surgery was delayed since the babys nasal breathing was adequate as a result of the insertion of a nasal tube. Since treatment depends on the severity of symptoms, it is appropriate in some cases to take a conservative approach at first, and to keep surgery as a last resort. Once a conservative approach has been selected for congenital nasal pyriform aperture stenosis, awareness of the life-threatening nature of the condition should be kept in mind, and a surgical approach must still be taken into account. PMID:24950703

  15. Management of recently traumatized maxillary central incisors by partial pulpotomy using MTA: Case reports with two-year follow-up

    PubMed Central

    Abarajithan, M.; Velmurugan, N.; Kandaswamy, D

    2010-01-01

    In traumatized, young, permanent teeth, pulpotomy is classically undertaken to promote apexogenesis. The objective is to promote root development and apical closure. Once root end development and apical closure is achieved, the root canal treatment is completed. However, it has been suggested that mere pulp exposure does not cause pulpitis in the absence of bacteria. Recent studies have proposed that as long as a good seal is ensured, root canal treatment may not be necessary following pulpotomy. In this article we report two cases of traumatized, fully matured, maxillary permanent central incisors, which have been treated with mineral trioxide aggregate following partial pulpotomy, with a two-year follow-up. PMID:20859487

  16. Evaluation of the Load-bearing Capacity of Fractured Incisal Edge of Maxillary Permanent Central Incisors restored with a Glass Fiber-reinforced Nanocomposite: An in vitro Study

    PubMed Central

    Srilatha, KT; Nandlal, B; Dhull, Kanika Singh

    2015-01-01

    ABSTRACT Objectives: The aim of this study was to evaluate and compare the load-bearing capacity of fractured incisal edge of maxillary permanent central incisors restored with a nanocomposite and a glass fiber-reinforced nanocomposite. Materials and methods: Thirty-six extracted sound maxillary central incisors randomly divided in three groups were used for the present study. Group I (control) contained untreated teeth. Samples in experimental groups II and III were prepared by cutting the incisal (one-third) part of the crown horizontally and subjected to enamel preparations and restored with a nanocomposite and a glass fiber-reinforced nanocomposite respectively. All restored teeth were stored in distilled water at room temperature for 24 hours. Fracture resistance was evaluated as peak load at failure (Newton) for samples tested in a cantilever-bending test using Hounsfield universal testing machine. Failure modes were microscopically examined. Results: Highest mean peak failure load (Newton) among experimental groups was observed in glass fiber-reinforced nano composite group (863.50 ± 76.12 N) followed by nanocomposite group (633.67 ± 40.14 N). One-way analysis of variance (ANOVA) revealed that the restoration technique significantly affected the load-bearing capacity (p < 0.001). Scheffe’s post-hoc comparison test (subset for α = 0.05) revealed that there was significant difference in the mean peak failure load values of nanocomposite and glass fiber-reinforced nanocomposite groups when considered together (p < 0.001). Experimental groups showed similar types of failure modes with majority occurring ascohesive and mixed type. Fifty-eight percent of the teeth in glass fiber-reinforced nanocomposite group fractured below the cementoenamel junction. Conclusion: By using fiber-reinforced composite substructure under conventional composites in the repair of fractured incisors, the load-bearing capacity of the restored incisal edge could be substantially increased. How to cite this article: Kumar PSP, Srilatha KT, Nandlal B, Dhull KS. Evaluation of the Load-bearing Capacity of Fractured Incisal Edge of Maxillary Permanent Central Incisors restored with a Glass Fiber-reinforced Nanocomposite: An in vitro Study. Int J Clin Pediatr Dent 2015;8(1):22-29. PMID:26124577

  17. Evaluation of the mineralization degree of the vestibular surface of the upper central incisors with a 655-nm diode laser in mouth breathers: preliminary results

    NASA Astrophysics Data System (ADS)

    Pinheiro Ladalardo, Thereza C. C. G.; Cappellette, Mario, Jr.; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.; Anthero de Azevedo, Ramiro; Pignatari, Shirley; Weckx, Luc L. M.

    2003-06-01

    Mouth breathing unbalances the physiological mechanisms of the dental surface hydration by compromising lip closure, and, very often, causing the vestibular positioning of upper incisors. That variance leads to the interruption of the dental demineralization and remineralization feedback, prevailing a demineralized condition of the dental surface which increases caries risk. The laser fluorescence examination allows an early demineralization diagnosis, thus it makes possible through preventive measures to minimize the risk factor - dental mineral structure loss - in the bacterial infection of the demineralized area, and hence, preventing invasive therapeutical procedures. A DIAGNOdent apparatus was used to evaluate the mineralization degree of the upper central incisors in 40 patients - twenty of them with a mouth breathing diagnosis; the remaining twenty were nasal breathers (control group). Age ranging from 6 to 12 years, both male and female. To measure the vestibular surface of the incisors, it was divided into 3 segments: cervical, medial and incisal. The average of the results pertaining to the mouth breathing patients was as follows: tooth 11 cervical third - 5.45, medial third - 7.15, incisal third - 7.95, and tooth 21 - cervical third - 5.95, medial third - 7.25, incisal third - 8.15. The control patients, nasal breathers, presented the following results: tooth 11 cervical third - 1.75, medial third - 2.30, incisal third - 1.85, and tooth 21 - cervical third - 1.80, medial third - 2.20, incisal third - 2.15. The mouth breathing patients showed demineralization in the teeth examined at the initial stage, subclinical, comparing with the control patients, nasal breathers, who did not present any mineral deficit in these teeth.

  18. Reconstruction and Intentional Replantation of a Maxillary Central Incisor with a Complete Vertical Root Fracture: A Rare Case Report with Three Years Follow up

    PubMed Central

    Dua, Deepti

    2015-01-01

    Vertical root fractures in teeth present with challenges not only with diagnosis but also with management. The prognosis in such teeth is generally questionable with extraction of the tooth being the most common treatment option. However, conservative treatment options such as reconstruction of the fractured fragments with adhesive resin followed by intentional replantation have been recently suggested. There are only a few case reports that describe management of complete vertical root fracture by reconstruction of fragments. The present case report describes successful management of an unusual complete vertical root fracture of a maxillary right central incisor in a 23-year-old male by reconstructing the fragments with a dual cure resin followed by intentional replantation. At the three year follow up, the tooth was asymptomatic, radiographically sound with probing depth and mobility within normal physiological limits. PMID:26501026

  19. Reconstruction and Intentional Replantation of a Maxillary Central Incisor with a Complete Vertical Root Fracture: A Rare Case Report with Three Years Follow up.

    PubMed

    Dua, Deepti; Dua, Ankur

    2015-09-01

    Vertical root fractures in teeth present with challenges not only with diagnosis but also with management. The prognosis in such teeth is generally questionable with extraction of the tooth being the most common treatment option. However, conservative treatment options such as reconstruction of the fractured fragments with adhesive resin followed by intentional replantation have been recently suggested. There are only a few case reports that describe management of complete vertical root fracture by reconstruction of fragments. The present case report describes successful management of an unusual complete vertical root fracture of a maxillary right central incisor in a 23-year-old male by reconstructing the fragments with a dual cure resin followed by intentional replantation. At the three year follow up, the tooth was asymptomatic, radiographically sound with probing depth and mobility within normal physiological limits. PMID:26501026

  20. Endodontic and Esthetic Management of a Dilacerated Maxillary Central Incisor Having Two Root Canals Using Cone Beam Computed Tomography as a Diagnostic Aid

    PubMed Central

    Sharma, Sarang; Grover, Shibani; Sharma, Vivek; Srivastava, Dhirendra; Mittal, Meenu

    2014-01-01

    Traumatic injuries to the primary dentition are quite common. When primary teeth are subjected to trauma, force transmission and/or invasion of the underlying tooth germs lying in close proximity can result in a variety of disturbances in the permanent successors. Few of these disturbances include hypoplasia, dilaceration, or alteration in the eruption sequence and pattern. Dilaceration is defined as an angulation or sharp bend or curve in the linear relationship of the crown of a tooth to its root. A rare case of maxillary left central incisor having crown dilaceration and Vertucci's type II canal configuration with symptomatic periapical periodontitis is reported. Cone beam computed tomography was used for better understanding of the anomaly and complicated root canal morphology. The tooth was successfully managed by nonsurgical root canal therapy and restoration with resin composite to restore esthetics. PMID:24955260

  1. Relationship of central incisor implant placement to the ridge configuration anterior to the nasopalatine canal in dentate and partially edentulous individuals: a comparative study

    PubMed Central

    2015-01-01

    Background. The aims of this study were to investigate the ridge contour anterior to the nasopalatine canal, and the difference between the incidences of the nasopalatine canal perforation in dentate and partially edentulous patients by cone-beam computed tomography. Methods. Cone-beam computed tomography scan images from 72 patients were selected from database and divided into dentate and partially edentulous groups. The configuration of the ridge anterior to the canal including palatal concavity depth, palatal concavity height, palatal concavity angle, bone height coronal to the incisive foramen, and bone width anterior to the canal was measured. A virtual implant placement procedure was used, and the incidences of perforation were evaluated after implant placement in the cingulum position with the long axis along with the designed crown. Results. Comparing with variable values from dentate patients, the palatal concavity depth and angle were greater by 0.9 mm and 4°, and bone height was shorter by 1.1 mm in partially edentulous patients, respectively. Bone width in edentulous patients was narrower than in dentate patients by 1.2 mm at incisive foramen level and 0.9 mm at 8 mm subcrestal level, respectively. After 72 virtual cylindrical implants (4.1 × 12 mm) were placed, a total of 12 sites (16.7%) showed a perforation and three-fourths occurred in partially edentulous patients. After replacing with 72 tapered implants (4.3 × 13 mm), only 6 implants (8.3%) broke into the canal in the partially edentulous patient group. Conclusions. The nasopalatine canal may get close to the implant site and the bone width anterior to the canal decreases after the central incisor extraction. The incidence of nasopalatine canal perforation may occur more commonly during delayed implant placement in central incisor missing patients. PMID:26557434

  2. Relationship of central incisor implant placement to the ridge configuration anterior to the nasopalatine canal in dentate and partially edentulous individuals: a comparative study.

    PubMed

    Jia, Xueting; Hu, Wenjie; Meng, Huanxin

    2015-01-01

    Background. The aims of this study were to investigate the ridge contour anterior to the nasopalatine canal, and the difference between the incidences of the nasopalatine canal perforation in dentate and partially edentulous patients by cone-beam computed tomography. Methods. Cone-beam computed tomography scan images from 72 patients were selected from database and divided into dentate and partially edentulous groups. The configuration of the ridge anterior to the canal including palatal concavity depth, palatal concavity height, palatal concavity angle, bone height coronal to the incisive foramen, and bone width anterior to the canal was measured. A virtual implant placement procedure was used, and the incidences of perforation were evaluated after implant placement in the cingulum position with the long axis along with the designed crown. Results. Comparing with variable values from dentate patients, the palatal concavity depth and angle were greater by 0.9 mm and 4°, and bone height was shorter by 1.1 mm in partially edentulous patients, respectively. Bone width in edentulous patients was narrower than in dentate patients by 1.2 mm at incisive foramen level and 0.9 mm at 8 mm subcrestal level, respectively. After 72 virtual cylindrical implants (4.1 × 12 mm) were placed, a total of 12 sites (16.7%) showed a perforation and three-fourths occurred in partially edentulous patients. After replacing with 72 tapered implants (4.3 × 13 mm), only 6 implants (8.3%) broke into the canal in the partially edentulous patient group. Conclusions. The nasopalatine canal may get close to the implant site and the bone width anterior to the canal decreases after the central incisor extraction. The incidence of nasopalatine canal perforation may occur more commonly during delayed implant placement in central incisor missing patients. PMID:26557434

  3. Management of Traumatized Permanent Incisors. Revascularization and Delayed Replantation.

    PubMed

    Gharechahi, Maryam; Shojaeian, Shiva

    2016-01-01

    This article reports a clinical case of a 9-year-old boy with a traumatic injury to the maxillary central incisors 24 hours after a fall in his schoolyard. The upper left central incisor was avulsed and was kept in saliva for four hours from the moment of trauma until its replantation. The right one was necrotized after one month. We describe successful revascularization treatment of right necrotic immature upper incisor and delayed replantation of left one. After 18 months, radiolucent lesions in the periapical areas of both maxillary central incisors had healed, and root apex development was noted with thickening of the walls in tooth #8. PMID:26939157

  4. Estimation of the rate of tooth wear in permanent incisors: a cross-sectional digital radiographic study.

    PubMed

    Ray, D S; Wiemann, A H; Patel, P B; Ding, X; Kryscio, R J; Miller, C S

    2015-06-01

    This study used conventional digital radiography to estimate the rate of tooth wear (TW) of maxillary and mandibular central incisors based on a cross-sectional study design. The crown length of 1239 permanent maxillary and mandibular central incisors from 346 persons (age groups: 10, 25, 40, 55 and 70 years ± 3) were measured by three calibrated dentists. Study teeth were intact incisally, had clearly visible incisal edges and cementoenamel junctions and had natural tooth antagonists. Measures were based on digital radiographic images (N = 666) archived in MiPACS within the electronic health record (axiUm(®)) from the College of Dentistry patient database. Incisor crown length decreased at a linear rate in both arches over the 60 years represented by the age groups. The average crown length for maxillary incisors in the youngest age group was 11.94 mm, which decreased by an average of 1.01 mm by median age 70. For mandibular incisors, the average crown length in the youngest age group was 9.58 mm, which decreased by an average of 1.46 mm in the oldest age group. Males and females showed similar rates of TW. Regardless of age, females demonstrated smaller mean crown height for maxillary incisors than males (P < 0.0001). Measures by the examiners demonstrated good agreement, with an interclass correlation coefficient of 0.869 and an average intra-examiner correlation of 99.5%, based on repeated measurements (n = 100). TW was estimated to average 1.01 mm for maxillary central incisors and 1.46 mm for mandibular central incisors by age 70 years. PMID:25756187

  5. Lower molar and incisor displacement associated with mandibular remodeling.

    PubMed

    Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L

    1997-01-01

    The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla. PMID:9107373

  6. Orthodontic treatment of severe anterior open bite and alveolar bone defect complicated by an ankylosed maxillary central incisor: a case report.

    PubMed

    Lin, Feiou; Sun, Hao; Yao, Linjie; Chen, Qiushuo; Ni, Zhenyu

    2014-01-01

    Incisor trauma is common in children, and can cause severe complications during adolescent growth and development. This report describes the treatment of a 16-year-old patient with severe anterior open bite due to ankylosis of the maxillary left incisor after dental trauma as an 8-year-old. No examination or active treatment was undertaken until he was 16 years old. Clinical examination revealed that the maxillary left incisor was severely intruded accompanied by a vertical alveolar bone defect. Orthodontic treatment combined with surgical luxation took 3 years and 7 months. During treatment, the intruded incisor was moved to the occlusal level and the alveolar bone defect was restored, achieving normal occlusion. After two years of retention, the maxillary left incisor was retained in a stable normal position with a slightly reduced overbite. This case demonstrates that surgical luxation with orthodontic traction can be an effective approach, especially when the ankylosed tooth has a single root. Long-term monitoring of orthodontic stability and the maintenance of periodontal health are crucial in the post-treatment period. PMID:25414141

  7. Effects of post materials and length on the stress distribution of endodontically treated maxillary central incisors: a 3D finite element analysis.

    PubMed

    Hsu, M-L; Chen, C-S; Chen, B-J; Huang, H-H; Chang, C-L

    2009-11-01

    Traditionally, using a long post can cause progressive removal of the root structure, complicate the ability to re-treat the tooth if necessary and make it difficult to apply an adhesive bonding agent into the root canal. It is unclear if a shorter post length can be applied when a light translucent glass fibre post and adhesive resin cement are used. The aim of this study was to evaluate the biomechanical performance of endodontically treated teeth restored with three post materials, glass-fibre, stainless steel and cast-nickel chromium posts and cores of different lengths of 7, 10 and 13 mm. A 3D finite element analysis model of the maxillary central incisor was constructed. An occlusal load of 300 N was applied to a node at the palatal surface of the crown at 45 degrees to the long axis of the tooth. von Mises stress analyses were carried out in three regions. Simulated data were collected for plotting various pattern graphics and conducting statistical tests. The pattern graphics showed that when the post length changed from 13 to 7 mm, the stress patterns were even and flat in all fibre-post groups, while the stress patterns of the metal-post groups showed an M-shaped peak and trough. Statistical tests showed that the shorter fibre post was superior to the longer metal post in some situations. Within the limitations of this study, it was concluded that when a metal post is used, the post should be as long as possible, while the biomechanical performance of a glass-fibre post combined with a composite resin core was less sensitive to post length. PMID:19840225

  8. Multi-disciplinary management of a patient with a post-traumatised incisor presenting concurrent replacement and inflammatory resorption: a case report.

    PubMed

    Doğramaci, Esma J; Rossi-Fedele, Giampiero; Jonest, Allan G

    2015-11-01

    This case report describes the multidisciplinary management of a young male who presented with a Class I incisor relationship and bi-maxillary dento-alveolar protrusion on a Class I skeletal base. The occlusion was complicated by an ankylosed and moderately infra-positioned upper left permanent central incisor, an anterior crossbite, crowding, a reduced overbite and centreline discrepancy. The incisor was traumatised and avulsed when the root was immature and the tooth was reimplanted with delay. On referral for orthodontic treatment at age 11 .5 years, the upper left central incisor was experiencing ankylosis-related (osseous replacement) resorption and external root resorption simultaneously. Aside from the orthodontic aims, it was important to address the disrupted alveolar development to facilitate later prosthodontic replacement of the upper left permanent central incisor by idealising the inter-coronal and inter-radicular spaces. Treatment consisted of fixed orthodontic appliances in conjunction with the extraction of all second premolars and the upper left permanent central incisor with episodic surgical curettage. An upper Hawlix retainer was provided immediately at debond and a cantilevered resin-retained bridge was placed four months later. PMID:26999896

  9. The fusion of three primary incisors: report of case.

    PubMed

    Mochizuki, K; Yonezu, T; Yakushiji, M; Machida, Y

    1999-01-01

    The occurrence of a fusion of three primary incisors is rare. A two-year-old Japanese girl was brought to the pediatric dental outpatient clinic, Tokyo Dental College, to receive a caries-prevention treatment. The fused tooth consisted of the maxillary primary central incisors and right maxillary lateral incisor. Primary left lateral incisor erupted normally and the other primary teeth were erupted. The radicular pulp chambers were fused into one for three fourths of the length from the apex, and only one root. The hair and skin of the patient appeared normal and no systemic abnormality or congenital disease was noted in the medical history of the patient and her family. The occurrence of a three-tooth fusion, and no supernumerary tooth was confirmed. PMID:10656127

  10. Effect of coffe and a cola-based soft drink on the color stability of bleached bovine incisors considering the time elapsed after bleaching

    PubMed Central

    PIROLO, Rodrigo; MONDELLI, Rafael Francisco Lia; CORRER, Gisele Maria; GONZAGA, Carla Castiglia; FURUSE, Adilson Yoshio

    2014-01-01

    There is no consensus about the waiting time necessary for the patient to start consuming beverages containing colorants again after bleaching. Objective: To evaluate the influence of beverages with coloring agents on bleached bovine incisors considering the time elapsed after bleaching. Materials and methods: Sixty bovine incisors were bleached with 35% hydrogen peroxide for in-office use (Whiteness HP Max) and divided into 10 groups. The color was evaluated with a spectrophotometer (Spectro Shade MICRO) before and after bleaching, employing the CIE-Lab system. After bleaching, the teeth were exposed for 5 min to coffee or cola-based soft drink (CBSD) at different periods after bleaching: 10 min, 1 h, 24 h, 48 h, and 72 h. Color (∆E) and lightness (∆L) variations were obtained from the CIE-Lab coordinates. Data were subjected to two-way ANOVA and Tukey HSD tests (p<0.05). Results: Significant differences were observed between groups for both the ∆L and ∆E values (p<0.001). All specimens presented a decrease in brightness (negative ∆L). The highest ∆E values were observed for teeth stained with a CBSD at 10 min and 1 h (4.12 and 4.16, respectively). Teeth pigmented with coffee presented ∆E values below 3.3 units for all evaluation times. Conclusion: The exposure to coffee after bleaching causes less color changes than the exposure to a CBSD regardless of the time after bleaching. PMID:25075672

  11. Social judgments made by children (10–15 year old) in relation to visible incisors trauma: School-based cross-sectional study in Khartoum state, Sudan

    PubMed Central

    Awooda, Elhadi Mohieldin; Ali, Yasmeen Abdul-Hai

    2015-01-01

    Background: Dento-alveolar trauma is a very common occurrence in childhood; however, there is a paucity of data about children's judgments in relation to dental status. There is a significant correlation between the children's incisor teeth status and the social judgments made by their peers. Aim: The purpose of this study was to determine whether the social attributes of a school child would be influenced by his or her incisor teeth status. Also, it is aimed to determine the judgment between male and female children and different age groups within the same class. Setting and Design: A descriptive cross-sectional study conducted among 178 male and female children from year 5 (age 10–11 years) of primary school and year 2 of secondary school (age 14–15 years) within Khartoum state. Materials and Methods: Students were invited to look at colored photographs of four different children's faces and to make a social judgment about these children's photographs. Using a previously validated child-centered questionnaire, participants rated subjects using a four-point Likert scale for three negative and six positive attributes. Statistical Analysis: Total attribute scores were tested for significant differences, according to whether the subject had visible incisor trauma or not, using t-test and analysis of variance (ANOVA) test with the level of significance set at P ≤ 0.05. Results: Children with visible incisor trauma were given more negative attributes than children without incisor trauma (P = 0.05). Results were similar in both genders and both school years. Younger students within the same class gave more negative attributes toward children with visible incisor trauma than their older peers, with P = 0.04 and P = 0.9 for children aged 10 years and 11 years, respectively. Conclusion: The data confirmed results of previous studies that children with visible incisor trauma are seen more negatively than those without visible incisor trauma. PMID:26539397

  12. Pulp revascularization after repositioning of impacted incisor with a dilacerated root and a detached apex.

    PubMed

    Plakwicz, Paweł; Kapuścińska, Agnieszka; Kukuła, Krzysztof; Czochrowska, Ewa Monika

    2015-06-01

    Severely impacted and dilacerated incisors are rarely considered for surgical exposure because they may not respond favorably to orthodontic extrusion. These incisors are often extracted, resulting in the need for tooth replacement; however, prosthetic solutions are limited in growing patients. Transalveolar autotransplantation of an impacted incisor may be the only method to preserve the natural tooth and maintain the shape of the alveolus. The severely impacted upper central incisor (#9) with a developing root was diagnosed in a 9-year-old girl. The unfavorable tooth position and dilaceration of its root made orthodontic extrusion of the impacted incisor impossible. Initial orthodontic space opening at the recipient site was performed before the surgery. Transalveolar transplantation of the impacted incisor to its normal position was performed to avoid tooth extraction. The incisor was later aligned using fixed orthodontic appliances. At the 5-year follow-up, the transplanted incisor presented features that were typical of a revascularized tooth (ie, obliteration of root canal but a positive response to vitality tests). Healthy periodontal tissues and continued root development were also noted. However, the root apex, which separated from the transplant at the time of the surgery, continued formation in its initial position. Transalveolar transplantation of an unfavorably impacted upper central incisor with a dilacerated root is a successful treatment, which stands the test of time. The early stage of root development allowed revascularization of the tooth despite dilaceration of the root and detachment of its apex. PMID:25770037

  13. Orthodontic retraction of autotransplanted premolar to replace ankylosed maxillary incisor with replacement resorption.

    PubMed

    Choi, Yoon Jeong; Shin, Sujung; Kim, Kyung-Ho; Chung, Chooryung J

    2014-04-01

    This case report describes the successful treatment of an adult with lip protrusion and a previously traumatized maxillary central incisor that had experienced replacement root resorption. An extracted premolar was transplanted into the incisor space and retracted orthodontically. Autotransplantation was successful with complete root formation and, combined with orthodontic treatment, provided a satisfying esthetic outcome. PMID:24703290

  14. Orthodontic intrusion of maxillary incisors: a 3D finite element method study

    PubMed Central

    Saga, Armando Yukio; Maruo, Hiroshi; Argenta, Marco André; Maruo, Ivan Toshio; Tanaka, Orlando Motohiro

    2016-01-01

    Objective: In orthodontic treatment, intrusion movement of maxillary incisors is often necessary. Therefore, the objective of this investigation is to evaluate the initial distribution patterns and magnitude of compressive stress in the periodontal ligament (PDL) in a simulation of orthodontic intrusion of maxillary incisors, considering the points of force application. Methods: Anatomic 3D models reconstructed from cone-beam computed tomography scans were used to simulate maxillary incisors intrusion loading. The points of force application selected were: centered between central incisors brackets (LOAD 1); bilaterally between the brackets of central and lateral incisors (LOAD 2); bilaterally distal to the brackets of lateral incisors (LOAD 3); bilaterally 7 mm distal to the center of brackets of lateral incisors (LOAD 4). Results and Conclusions: Stress concentrated at the PDL apex region, irrespective of the point of orthodontic force application. The four load models showed distinct contour plots and compressive stress values over the midsagittal reference line. The contour plots of central and lateral incisors were not similar in the same load model. LOAD 3 resulted in more balanced compressive stress distribution. PMID:27007765

  15. Two-dimensional photoelastic stress analysis of traumatized incisor.

    PubMed

    Topbasi, B; Gunday, M; Bas, M; Turkmen, C

    2001-01-01

    In this study, stress of traumatized incisor and the effect of stress on tooth and alveolar bone was studied with two-dimensional photoelasticity. Two homogeneous two-dimensional maxillary central incisor models were prepared. Loads were applied to the labial side of incisal edge and middle third of the crown at angles of 45 degrees and 90 degrees. It was observed that stress was increased on teeth and alveolar bone when load was applied 90 degrees on labial side of incisal edge. PMID:11445918

  16. Evaluating Stress Distribution Pattern in Periodontal Ligament of Maxillary Incisors during Intrusion Assessed by the Finite Element Method

    PubMed Central

    Salehi, Parisa; Gerami, Alayar; Najafi, Amirhosein; Torkan, Sepideh

    2015-01-01

    Statement of the Problem The use of miniscrews has expedited the true maxillary incisor intrusion and has minimized untoward side effects such as labial tipping. Purpose The aim of this study was to assess the stress distribution in the periodontal ligament of maxillary incisors when addressed to different models of intrusion mechanics using miniscrews by employing finite element methods. The degree of relative and absolute intrusion of maxillary incisors in different conditions was also evaluated. Materials and Method Finite element model of maxillary central incisor to first premolar was generated by assembling images obtained from a three-dimensional model of maxillary dentition. Four different conditions of intrusion mechanics were simulated with different placement sites of miniscrews as well as different points of force application. In each model, 25-g force was applied to maxillary incisors via miniscrews. Results In all four models, increased stress values were identified in the apical region of lateral incisor. Proclination of maxillary incisors was also reported in all the four models. The minimum absolute intrusion was observed when the miniscrew was placed between the lateral incisor and canine and the force was applied at right angles to the archwire, which is very common in clinical practice. Conclusion From the results yield by this study, it seems that the apical region of lateral incisor is the most susceptible region to root resorption during anterior intrusion. When the minimum flaring of maxillary incisors is required in clinical situations, it is suggested to place the miniscrew halfway between the roots of lateral incisor and canine with the force applied to the archwire between central and lateral incisor. In order to achieve maximum absolute intrusion, it is advised to place miniscrew between the roots of central and lateral incisors with the force applied at a right angle to the archwire between these two teeth. PMID:26636119

  17. Ectopic eruption of permanent incisors after predecessor pulpectomy: five cases.

    PubMed

    Tannure, Patricia Nivoloni; Fidalgo, Tatiana Kelly da Silva; Barcelos, Roberta; Gleiser, Rogerio; Primo, Laura Guimaraes

    2011-01-01

    Pulpectomy in primary teeth is a common technique that preserves teeth in the oral environment and maintains or recovers periapical tissues to a healthy condition. This article describes the ectopic eruption of permanent incisors whose primary predecessors underwent pulpectomy using ZOE filler paste. In a group of 135 teeth that received pulpectomy therapy due to caries, 10 primary maxillary incisors had overretention and were followed for at least 3.5 years (mean time of 4.2 years), both clinically and radiographically, until the permanent teeth erupted. The proposed treatment included extraction of the overretained primary incisors based on permanent successor eruption chronology and contralateral eruption. Seven permanent teeth erupted ectopically. Autocorrection of the permanent tooth positions was observed in five cases. It can be concluded that periodic clinical and radiographic assessments are essential to verify radicular and filling paste resorptions and to avoid overretention and any subsequent malocclusion. PMID:21903556

  18. Impacted permanent incisors associated with compound odontoma.

    PubMed

    Machado, Cintia de Vasconcellos; Knop, Luégya Amorin Henriques; da Rocha, Maria Celina Barreiros Siquara; Telles, Paloma Dias da Silva

    2015-01-01

    Odontomas are the most common odontogenic tumours of the maxillary bones, characterised by a slow growth and benign behaviour. They are usually small, asymptomatic and diagnosed after routine radiographic examination. The aim of this study was to report a case of a compound odontoma in the anterior maxilla of a 7-year-old girl, which was causing the impaction of the maxillary right central and lateral incisors, as well as the prolonged retention of the corresponding primary teeth. We also aimed to review the literature about these tumours, since they are not part of the dentist's day-to-day clinical practice. The clinical and radiographic features, the diagnosis and treatment of the case were discussed in this work. PMID:25583937

  19. [Incisor repositioning: a new approach in orthodontics].

    PubMed

    Dallel, Ines; Khemiri, Mourad; Fathallah, Safa; Ben Rejeb, Salwa; Tobji, Samir; Ben Amor, Adel

    2015-12-01

    Lower incisors axis has a "key" position in different cephalometric analysis. However, several critics are directed towards the cephalometric profile and cephalometric landmarks (point, line and angle). The published norms and the cephalometric standards recommended for the optimal positioning of incisors could only be used as general clinical guidelines. Incisor repositioning to achieve optimal facial aesthetics requires taking into consideration the hard and soft tissues of the face, the profile, the muscular dynamics as well as the facial growth. In this work, we propose a new approach of incisor repositioning taking into account the variability of periodontal, functional and aesthetic factors. PMID:26655419

  20. A comparative study of incisor procumbency and mandibular morphology in vampire bats.

    PubMed

    Davis, Jillian S; Nicolay, Christopher W; Williams, Susan H

    2010-07-01

    The three species of vampire bats (Phyllostomidae: Desmodontinae), Desmodus rotundus, Diaemus youngi, and Diphylla ecaudata, are the only mammals that obtain all nutrition from vertebrate blood (sanguinivory). Because of the unique challenges of this dietary niche, vampire bats possess a suite of behavioral, physiological, and morphological specializations. Morphological specializations include a dentition characterized by small, bladelike, non-occlusive cheek teeth, large canines, and extremely large, procumbent, sickle-shaped upper central incisors. The tips of these incisors rest in cuplike pits in the mandible behind the lower incisors (mandibular pits). Here, we use microCT scanning and high-resolution radiography to describe the morphology of the mandible and anterior dentition in vampire bats, focusing on the relationship between symphyseal fusion, mandibular pit size, incisor size, and procumbency. In Desmodus and Diaemus, highly procumbent upper incisors are associated with relatively small mandibular pits, an unfused mandibular symphysis with substantial bony interdigitations linking the dentaries, and a diastema between the lower central incisors that helps to facilitate the lapping of blood from a wound. In Diphylla, less procumbent upper incisors are associated with relatively large mandibular pits, a completely fused mandibular symphysis, and a continuous lower toothrow lacking a central diastema. We hypothesize that symphyseal morphology and the presence or absence of the diastema are associated with the angle of upper incisor procumbency and mandibular pit development, and that spatial constraints influence the morphology of the symphysis. Finally, this morphological variation suggests that Diphylla utilizes a different feeding strategy as compared to Desmodus and Diaemus, possibly resulting from the functional demands of specialization on avian, rather than mammalian, blood. PMID:20544874

  1. Dental fast track: prenatal enamel growth, incisor eruption, and weaning in human infants.

    PubMed

    Mahoney, Patrick

    2015-03-01

    Correlation between the timing of permanent first molar eruption and weaning age in extant primates has provided a way to infer a life history event in fossil species, but recent debate has questioned whether the same link is present in human infants. Deciduous incisors erupt at an age when breast milk can be supplemented with additional foods (mixed feeding), and weaning is typically complete before permanent first molars erupt. Here, I use histological methods to calculate the prenatal rate by which enamel increases in thickness and height on human deciduous incisors, canines, and molars (n = 125). Growth trajectories for each tooth type are related to the trimesters and assessed against the eruption sequence and final crown height. Analyses show that central incisors initiate early in the second trimester with significantly faster secretion rates relative to canines and second molars, which initiate closer to birth. Even though initial extension rates were correlated with crown height and scaled with positive allometry within each tooth class, the relatively short incisors still increased in height at a significantly faster rate than the taller canines and molars. The incisor prenatal "fast track" produces a greater proportion of the crown before birth than all other tooth types. This growth mechanism likely facilitates early incisor eruption at a time when the mixed feeding of infants can be initiated as part of the weaning process. Findings provide a basis from which to explore new links between developmental trends along the tooth row and mixed feeding age in other primates. PMID:25388809

  2. Incisor wear and age in Yellowstone bison

    USGS Publications Warehouse

    Christianson, D.A.; Gogan, P.J.P.; Podruzny, K.M.; Olexa, E.M.

    2005-01-01

    Biologists commonly use tooth eruption and wear patterns or cementum annuli techniques to estimate age of ungulates. However, in some situations the accuracy or sampling procedures of either approach are undesirable. We investigated the progression of several quantitative measures of wear with age, using permanent first incisors from Yellowstone bison (Bison bison), and tested for differences between sexes and herds. We further investigated the relationship of wear and age to explore an age-estimation method. Labial-lingual width (LLW) correlated best with assigned age (r2=0.66, males; r2=0.76 females). Labial-lingual width differed between sexes, with females showing ∼0.2 mm more wear than males. Additionally, differences in rate of wear existed between bison of the northern and central Yellowstone herds (1.2 and 0.9 mm/year, respectively). We developed a regression formula to test the power of LLW as an estimator of Yellowstone bison age. Our method provided estimated ages within 1 year of the assigned age 73% and 82% of the time for female and male bison, respectively.

  3. Biomechanical considerations in mandibular incisor extraction cases.

    PubMed

    Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Dasari, Arun Kumar; Sinojiya, Jay

    2015-01-01

    Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases. PMID:25881386

  4. Management of horizontally impacted dilacerated lateral incisor

    PubMed Central

    Katta, Anil Kumar; Peddu, Revathi; Vannala, Venkataramana; Dasari, Vaishnavi

    2015-01-01

    Impaction of maxillary lateral incisor with odontome and retained deciduous tooth is not often seen in regular dental practice. Impaction of anterior teeth cause generalized spacing which affects the esthetics of the face. Here we report a case of an 18-year-old patient with horizontally impacted dilacerated lateral incisor, which was bought into occlusion with the help of orthodontic tooth movement within a span of 18 months. PMID:26538954

  5. Management of a hyperdivergent Class III malocclusion, maxillary midline diastema, and infected mandibular incisors in a young adult.

    PubMed

    Suri, Sunjay; Utreja, Ashok

    2003-12-01

    This is a case report of a 20-year-old woman with a hyperdivergent Class III malocclusion, infected mandibular incisors, maxillary midline diastema, and a mild tongue thrust. Extraction of the infected incisors and orthodontic treatment involving partial mesial movement of the remaining mandibular teeth produced a well-intercuspated Class III occlusion. After successful orthodontic treatment, a 4-unit bridge with pontics for the mandibular central incisors completed the rehabilitation and met the functional, esthetic, and occlusal treatment goals. Occlusal stability of the treatment result has been excellent in the 3-year follow-up. PMID:14666089

  6. Clinical management of a fused mandibular lateral incisor with supernumerary tooth: A case report

    PubMed Central

    Aydemir, Seda; Ozel, Emre; Arukaslan, Goze; Tekce, Neslihan

    2016-01-01

    The purpose of this report is to present a rare case of a fused mandibular lateral incisor with supernumerary tooth with a follow-up for 18-months. A 35-year-old female patient was referred to our clinic with an extraoral sinus tract in the chin. The intraoral diagnosis revealed the fusion of her mandibular lateral incisors. Vitality pulp tests were negative for mandibular right central and lateral incisors. Radiographic examinations showed a fused tooth with two separate pulp chambers, two distinct roots, and two separate root canals. There were also periapical lesion of fused teeth and mandibular right central incisor, so endodontic treatment was carried out the related teeth. Radiographic examination revealed a complete healing of the lesion postoperatively at the end of 18-months. This paper reports the successful endodontic and restorative treatment of unilateral fused incisors. Because of the abnormal morphology of the crown and the complexity of the root canal system in fused teeth, treatment protocols require special attention. PMID:26962321

  7. Biomechanics of incisor retraction with mini-implant anchorage.

    PubMed

    Upadhyay, Madhur; Yadav, Sumit; Nanda, Ravindra

    2014-09-01

    Mini-implants have been successfully incorporated into orthodontic practice all over the world. One of the most popular applications of mini-implant anchorage is to facilitate retraction of the anterior teeth. This article reviews the mechanics involved in anterior tooth retraction with mini-implant supported anchorage. An attempt has been made to synthesize information available in the literature and present it in a manner that is easily understandable from a clinical perspective. We discuss the fundamental differences mini-implant based incisor retraction has when compared to conventional techniques, mechanical factors affecting this process and provide a step-by-step analysis of incisor retraction. In addition, various models of space closure are discussed that have evolved through careful evaluation of in vitro and in vivo experiments. PMID:25138361

  8. Dynamics-based centrality for directed networks.

    PubMed

    Masuda, Naoki; Kori, Hiroshi

    2010-11-01

    Determining the relative importance of nodes in directed networks is important in, for example, ranking websites, publications, and sports teams, and for understanding signal flows in systems biology. A prevailing centrality measure in this respect is the PageRank. In this work, we focus on another class of centrality derived from the Laplacian of the network. We extend the Laplacian-based centrality, which has mainly been applied to strongly connected networks, to the case of general directed networks such that we can quantitatively compare arbitrary nodes. Toward this end, we adopt the idea used in the PageRank to introduce global connectivity between all the pairs of nodes with a certain strength. Numerical simulations are carried out on some networks. We also offer interpretations of the Laplacian-based centrality for general directed networks in terms of various dynamical and structural properties of networks. Importantly, the Laplacian-based centrality defined as the stationary density of the continuous-time random walk with random jumps is shown to be equivalent to the absorption probability of the random walk with sinks at each node but without random jumps. Similarly, the proposed centrality represents the importance of nodes in dynamics on the original network supplied with sinks but not with random jumps. PMID:21230545

  9. Dynamics-based centrality for directed networks

    NASA Astrophysics Data System (ADS)

    Masuda, Naoki; Kori, Hiroshi

    2010-11-01

    Determining the relative importance of nodes in directed networks is important in, for example, ranking websites, publications, and sports teams, and for understanding signal flows in systems biology. A prevailing centrality measure in this respect is the PageRank. In this work, we focus on another class of centrality derived from the Laplacian of the network. We extend the Laplacian-based centrality, which has mainly been applied to strongly connected networks, to the case of general directed networks such that we can quantitatively compare arbitrary nodes. Toward this end, we adopt the idea used in the PageRank to introduce global connectivity between all the pairs of nodes with a certain strength. Numerical simulations are carried out on some networks. We also offer interpretations of the Laplacian-based centrality for general directed networks in terms of various dynamical and structural properties of networks. Importantly, the Laplacian-based centrality defined as the stationary density of the continuous-time random walk with random jumps is shown to be equivalent to the absorption probability of the random walk with sinks at each node but without random jumps. Similarly, the proposed centrality represents the importance of nodes in dynamics on the original network supplied with sinks but not with random jumps.

  10. Age estimation from pulp/tooth area ratio in maxillary incisors among Egyptians using dental radiographic images.

    PubMed

    Zaher, Jaklin Fekri; Fawzy, Irene Atef; Habib, Sahar Refaat; Ali, Magdy Mohamed

    2011-02-01

    Age estimation from dental radiographs is a non-destructive, simple method to obtain information. The aim of this study was to determine the reliability of age estimation from Egyptians' incisors radiographs. 144 periapical radiographs of maxillary (central & lateral) incisors (both sexes) aged 12-60 were used. Digital camera was used to image the radiographs. Images were computed and pulp/tooth area ratios were determined by AutoCAD Program. Data were subjected to correlation and regression analysis which showed statistically significant correlation (r = 0.23 &P = 0.006 for maxillary central incisors and r = -0.2 &P = 0.05 for maxillary lateral incisors) between age and pulp tooth area ratio. Linear regression equations were determined separately for both central and lateral incisors along with the corresponding Standard Error of Estimate, which ranged from 1.2 to 5.08 years. Consequently, it was concluded that pulp/tooth area ratios of incisors are reliable for estimation of age among Egyptians in forensic work. PMID:21315299

  11. Precision of marginal adaptation of the incisor and molar Procera allceram crown copings.

    PubMed

    Pilathadka, S; Slezk, R; Srinivasan, V; Ivanckov, R

    2008-01-01

    The primary objective of this in vitro study was to compare the absolute marginal discrepancy (AMD) of CAD/CAM produced Procera AllCeram crown copings, fabricated on die stone master models of two different tooth groups, incisor and molar. Two maxillary central incisors and two first molars typodont teeth were prepared with 0.8 mm of circumferential chamfer, duplicated 9 times to obtain 36 die stone models and allotted into three groups of 12 models (incisors = 6 & molars = 6). Procera AllCeram 0.6 mm copings were fixed with zinc phosphate (AZ), glass ionomer (AG) and resin (AR) cement accordingly under 50 N static finger force. The AMDs were measured using the scanning electron microscope (SEM) on four axial walls with 4 measurements on each wall to obtain 16 readings for one tooth. Statistical analysis of the data was performed using the non-parametric test of Kruskal-Wallis and Mann-Whitney test. The analysis did not find any significant differences in the mean AMD of incisor and molar crown copings, and in different axial surfaces too (p < or = 0.05). Recorded mean AMD of incisor copings were AZ group 59 microm, AG 37.9 microm, and AR 44.4 microm and molar copings were AZ 48.8 microm, AG 27 microm, and AR 50.2 microm. It can be concluded that AMD of Procera AllCeram copings were within accepted level of 100 microm. Incisors showed higher AMD than molars. Molars demonstrated the higher AMD on mid-distal and mid-lingual surfaces whereas for incisor it was mid-buccal and mid-lingual surface. PMID:19097392

  12. Incisor toothwear caused by a dietary habit involving chillies-a case report.

    PubMed

    Addy, Liam; Antonarakis, Gregory

    2005-05-01

    Toothwear cases can vary dramatically in their presentation, with some displaying quite peculiar patterns. This case report outlines a patient's unusual eating habit that had led to a localized pattern of toothwear affecting his maxillary and mandibular central incisors. The patient had a habit of eating fresh chillies between his incisors after most evening meals; this was followed by immediate toothbrushing, which he had done for many years. This case illustrates that, not only is diet analysis important in identifying aetiological factors in toothwear cases, but also dietary habits. PMID:15938340

  13. Two hominin incisor teeth from the middle Pleistocene site of Boxgrove, Sussex, England.

    PubMed

    Hillson, S W; Parfitt, S A; Bello, S M; Roberts, M B; Stringer, C B

    2010-11-01

    In 1995-1996 two isolated hominin lower incisors were found at the middle Pleistocene site of Boxgrove in England, with Lower Palaeolithic archaeology. Boxgrove 2 is a permanent lower right central incisor and Boxgrove 3 a permanent lower left lateral incisor. They were found separately, but close to one another and appear to belong to the same individual. The Boxgrove 1 tibia discovered in 1993 came from a different stratigraphic context and is thus believed to represent a different individual. This paper describes the morphology of the incisors, which is similar to other middle Pleistocene hominin specimens and, as with the tibia, suggests that they could be assigned to Homo heidelbergensis (recognising that the taxonomic status of this species is still a matter of debate). The incisors show substantial attrition associated with secondary dentine deposition in the pulp chamber and clearly represent an adult. They also show extensive patterns of non-masticatory scratches on the labial surfaces of both crown and root, including some marks which may have been made postmortem. The roots were exposed in life on their labial sides by a large dehiscence, extending almost to the root apex. This is demonstrated by deposits of calculus, polishing, and scratching on the exposed surfaces. The dehiscence may have been caused by repeated trauma to the gingivae or remodelling of the tooth-supporting tissues in response to large forces applied to the front of the dentition. PMID:20828787

  14. Surgical Derotation Technique: A Novel Approach in the Management of Rotated Immature Permanent Incisor

    PubMed Central

    Krishnapriya, V; Sriram, CH; Reddy, Maheshwar KR

    2015-01-01

    ABSTRACT Surgical derotation is a method of placing a rotated tooth in normal alignment in a dental arch; surgically, immediately and permanently. It is a potentially convenient and cost-effective treatment modality as compared to conventional orthodontic procedure for rotated maxillary incisor with open apex. Here is a presentation of a severely rotated maxillary left permanent central incisor in a nine and half years old girl, with a radiographic evidence of immature root apex which was surgically derotated, orthodontically retroclined and intruded to its normal position. Postsurgical clinical and radiographic evaluation was done for a period of one and half years to confirm the vitality and continued physiological root formation of the affected tooth. How to cite this article: Dutta B, Krishnapriya V, Sriram CH, Reddy MKR. Surgical Derotation Technique: A Novel Approach in the Management of Rotated Immature Permanent Incisor. Int J Clin Pediatr Dent 2015;8(3):220-223. PMID:26604541

  15. Molars and incisors: show your microarray IDs

    PubMed Central

    2013-01-01

    Background One of the key questions in developmental biology is how, from a relatively small number of conserved signaling pathways, is it possible to generate organs displaying a wide range of shapes, tissue organization, and function. The dentition and its distinct specific tooth types represent a valuable system to address the issues of differential molecular signatures. To identify such signatures, we performed a comparative transcriptomic analysis of developing murine lower incisors, mandibular molars and maxillary molars at the developmental cap stage (E14.5). Results 231 genes were identified as being differentially expressed between mandibular incisors and molars, with a fold change higher than 2 and a false discovery rate lower than 0.1, whereas only 96 genes were discovered as being differentially expressed between mandibular and maxillary molars. Numerous genes belonging to specific signaling pathways (the Hedgehog, Notch, Wnt, FGF, TGFβ/BMP, and retinoic acid pathways), and/or to the homeobox gene superfamily, were also uncovered when a less stringent fold change threshold was used. Differential expressions for 10 out of 12 (mandibular incisors versus molars) and 9 out of 10 selected genes were confirmed by quantitative reverse transcription-PCR (qRT-PCR). A bioinformatics tool (Ingenuity Pathway Analysis) used to analyze biological functions and pathways on the group of incisor versus molar differentially expressed genes revealed that 143 genes belonged to 9 networks with intermolecular connections. Networks with the highest significance scores were centered on the TNF/NFκB complex and the ERK1/2 kinases. Two networks ERK1/2 kinases and tretinoin were involved in differential molar morphogenesis. Conclusion These data allowed us to build several regulatory networks that may distinguish incisor versus molar identity, and may be useful for further investigations of these tooth-specific ontogenetic programs. These programs may be dysregulated in transgenic animal models and related human diseases leading to dental anomalies. PMID:23531410

  16. Location and dimensions of access cavity in permanent incisors, canines, and premolars

    PubMed Central

    Krapež, Jana; Fidler, Aleš

    2013-01-01

    Background: Ideal access cavity assures unobstructed straight-line access to the apical third of the root canal and preserves tooth structure. Aim: The aim of the study was to determine the location and dimensions of access cavity with straight-line access in incisors, canines, and premolars and to evaluate the largest diameter of their root canals in the mesiodistal and vestibulooral direction. Materials and Methods: Twenty extracted teeth of each group were randomly selected and digitally radiographed from the mesiodistal and vestibulooral direction. Position of the straight-line access midline in relation to anatomical landmarks (incisal edges, fissures, and cusps) was recorded. The largest diameters in mesiodistal and vestibulooral direction were measured. Relative frequencies of access position and mean and standard deviation of both diameters were calculated. Results: For the anterior teeth, the predominant location of straight-line access was from incisal edge, except for maxillary central incisors, where location was equally distributed between incisal edge and oral surface. In mandibular premolars, the straight-line access was positioned vestibular from central fissure. In mesiodistal direction, the largest diameter was found for maxillary central incisors and canines (1.54 mm), while the smallest diameter was found for mandibular incisors (0.64 mm). In vestibulooral direction, the largest diameter was found for maxillary first premolar (5.28 mm), while the smallest diameter was found for maxillary lateral incisor (1.39 mm). Conclusions: Knowledge of location and size of access cavity facilitates achieving balance between straight-line access to the apical third of the root canal and preservation of tooth structure. PMID:24082567

  17. Forces that fracture teeth during extraction with mandibular premolar and maxillary incisor forceps.

    PubMed

    Ahel, V; Ćabov, T; Špalj, S; Perić, B; Jelušić, D; Dmitrašinović, M

    2015-12-01

    Our aim was to measure the forces that fracture teeth during extraction based on the effectiveness of the extraction forceps, and to compare them with data collected about forces applied to extracted teeth that did not fracture. We studied 208 patients whose teeth fractured during both the standard and our new method of extraction: maxillary incisors (n=79) extracted with forceps 1 (maxillary incisor forceps), and both maxillary (n=95) and mandibular incisors (n=34) extracted with forceps 13 (mandibular premolar forceps). Forces needed to fracture were assessed with a specially-designed instrument for measuring pressure and rotation. Mean (SD) pressure at the fracture site was significantly higher in maxillary incisors extracted with forceps 1 (1.26 (0.26) bar) then in both maxillary and mandibular incisors extracted with forceps 13 (0.96 (0.19) and 0.98 (0.16), p<0.001). Pressure at dislocation and both left and right rotation showed similar patterns. Pressure correlated to root surfaces of teeth ranging from r=0.35-0.54 but the correlation coefficients did not differ significantly between the teeth-forceps groups. Pressure was higher in fractured than in extracted teeth, and this varied from 3%-48%. In conclusion, forces that break teeth during extractions are sometimes only slightly higher than the extraction forces, so caution is needed during extraction. PMID:26346589

  18. Reattachment of fractured teeth fragments in mandibular incisors: a case report

    PubMed Central

    Yousef, Mohammed K

    2015-01-01

    The majority of dental trauma involves anterior teeth, especially the maxillary central incisors. A mandibular incisor fracture with or without pulp tissue involvement is considerably less common. Different approaches for treating these fractured teeth have been reported in the literature. The type of treatment rendered depends mainly on the extent of fracture, pulp involvement, radicular fracture, biologic width infringement or violation, and presence of the fractured piece. This case report illustrates reattachment of fractured fragments on two mandibular incisors without pulp exposure using a new proposed reattachment method using a combination of two different types of composite materials together with an orthodontic lingual retention wire. An 8-year-old female patient presented with fractured mandibular left incisors (Ellis class II fracture). Broken pieces were saved and brought in a closed container in water. Periapical radiographs revealed no evidence of pulpal involvement in either tooth and no periapical radiolucency was noticed. Fractured fragments and the broken teeth were prepared with circumferential bevels. Reattachment of the fractured fragments were done using two types of composite resin materials and a lingual orthodontic retention wire was also used. The patient was recalled after 8 months to follow up both teeth. Clinical examination revealed excellent composite restorations covering the fracture lines. PMID:25897267

  19. Reinforcement of bonded crown fractured incisors with porcelain veneers.

    PubMed

    Andreasen, F M; Daugaard-Jensen, J; Munksgaard, E C

    1991-04-01

    A method is described by which porcelain laminate veneers are used to reinforce crown-fractured incisors which have been restored by reattachment of enamel-dentin fragments using enamel etching and a dentin bonding system. In an experimental model using sheep incisors, it was found that fracture strength equal to that of intact incisors could be achieved by employing this method. This is in contrast to fracture strengths of reattached enamel-dentin tooth fragments without porcelain laminates which were only 50% of intact incisors. It is suggested that porcelain laminate veneers may be used to supplement fragment bonding, thereby enhancing dental esthetics and function. PMID:1782899

  20. Current controversies in late incisor crowding.

    PubMed

    Samspon, W J

    1995-01-01

    Although the terminology is mildly controversial, late incisor crowding (tertiary crowding, late secondary crowding, post-adolescent crowding) is widely regarded as a normal maturation event which is likely to affect most individuals to some extent. Disagreement arises when attempts are made to quantify the change and to predict the timing of the crowding. Most young adults experience some degree of loss of incisor alignment, usually near the anticipated emergence time for the third molars, and almost characteristically it is the lower anterior teeth which best demonstrate the phenomenon. Unfortunately, the physiological crowding changes are frequently confused with orthodontic treatment relapse. Greater controversy surrounds the aetiology of the undesirable crowding changes and despite many attempts we are still not in the enlightened position of explaining, predicting or preventing the problem (except by permanent retention). It is illogical to assume a single cause as the beguilingly simple observation of crowding belies the complexity of possible interacting factors. Perhaps it is a capricious combination of: tooth size and arch form; facial growth pattern (differential soft tissue and skeletal maturation); continuing late growth rotations; cumulative effects of resting, functional and parafunctional soft tissue pressures; lack of compensating attrition; and an ill-defined, mesially acting force emanating from the back of the dental arch. Many theories have attempted to resolve the mystery of the mesially acting force, including: pressure from erupting third molars; an inherent mesial migration; continuing mesial and occlusal dental drifting; maturation and contraction of periodontal soft tissues (particularly the transseptal fibres); the anterior component of occlusal forces; and the lower anterior arch contracting influence of the incisor overbite.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7605082

  1. In vivo administration of dental epithelial stem cells at the apical end of the mouse incisor.

    PubMed

    Orsini, Giovanna; Jimenez-Rojo, Lucia; Natsiou, Despoina; Putignano, Angelo; Mitsiadis, Thimios A

    2015-01-01

    Cell-based tissue regeneration is an attractive approach that complements traditional surgical techniques for replacement of injured and lost tissues. The continuously growing rodent incisor provides an excellent model system for investigating cellular and molecular mechanisms that underlie tooth renewal and regeneration. An active population of dental epithelial progenitor/stem cells located at the posterior part of the incisor, commonly called cervical loop area, ensures the continuous supply of cells that are responsible for the secretion of enamel matrix. To explore the potential of these epithelial cells in therapeutic approaches dealing with enamel defects, we have developed a new method for their in vivo administration in the posterior part of the incisor. Here, we provide the step-by-step protocol for the isolation of dental epithelial stem cells and their delivery at targeted areas of the jaw. This simple and yet powerful protocol, consisting in drilling a hole in the mandibular bone, in close proximity to the cervical loop area of the incisor, followed up by injection of stem cells, is feasible, reliable, and effective. This in vivo approach opens new horizons and possibilities for cellular therapies involving pathological and injured dental tissues. PMID:25914649

  2. In vivo administration of dental epithelial stem cells at the apical end of the mouse incisor

    PubMed Central

    Orsini, Giovanna; Jimenez-Rojo, Lucia; Natsiou, Despoina; Putignano, Angelo; Mitsiadis, Thimios A.

    2015-01-01

    Cell-based tissue regeneration is an attractive approach that complements traditional surgical techniques for replacement of injured and lost tissues. The continuously growing rodent incisor provides an excellent model system for investigating cellular and molecular mechanisms that underlie tooth renewal and regeneration. An active population of dental epithelial progenitor/stem cells located at the posterior part of the incisor, commonly called cervical loop area, ensures the continuous supply of cells that are responsible for the secretion of enamel matrix. To explore the potential of these epithelial cells in therapeutic approaches dealing with enamel defects, we have developed a new method for their in vivo administration in the posterior part of the incisor. Here, we provide the step-by-step protocol for the isolation of dental epithelial stem cells and their delivery at targeted areas of the jaw. This simple and yet powerful protocol, consisting in drilling a hole in the mandibular bone, in close proximity to the cervical loop area of the incisor, followed up by injection of stem cells, is feasible, reliable, and effective. This in vivo approach opens new horizons and possibilities for cellular therapies involving pathological and injured dental tissues. PMID:25914649

  3. Dens invaginatus in a geminated maxillary lateral incisor.

    PubMed

    Pallivathukal, Renjith George; Misra, Alok; Nagraj, Sumanth Kumbargere; Donald, Preethy Mary

    2015-01-01

    Dens invaginatus (DI) and gemination are two developmental abnormalities that are well reported in the dental literature, but their coexistence in a single tooth is rare. Such situations worsen the risk factors associated with these anomalies, and the treatment plan should be customised as they possess altered morphology and anatomy. A 19-year-old girl came for evaluation of a cracked tooth in the front region of the upper jaw. The tooth showed clinical features of gemination and radiographic features of DI, and was diagnosed as DI in geminated maxillary lateral incisor. The differential diagnoses based on clinical appearance without radiographic investigation may warrant the treatment approach if these two abnormalities coexist in a single tooth. The report also highlights the importance of three-dimensional imaging in diagnosis and treatment planning of teeth with altered pulp canal anatomy. There are few reported cases in the literature detailing the treatment options for these two anomalies occurring in the same tooth. PMID:26002668

  4. An Identification Key to Rodent Prey in Owl Pellets from the Northwestern and Southeastern United States: Employing Incisor Size to Distinguish among Genera

    ERIC Educational Resources Information Center

    Hager, Stephen B.; Cosentino, Bradley J.

    2006-01-01

    We present an identification key to the common rodent prey found in owl pellets from the Northwestern (NW) and Southeastern (SE) United States that is based on differences in incisor size (arc diameter) among genera.

  5. Cone beam-computed topographic evaluation of a central incisor with an open apex and a failed root canal treatment using one-step apexification with Biodentine™: A case report.

    PubMed

    Sinha, Nidhi; Singh, Bijay; Patil, Santosh

    2014-05-01

    A symptomatic endodontically treated immature tooth with periapical pathology presents multiple challenges to the clinician. Owing to incomplete root formation, gutta percha removal has to be done carefully without further damaging the periapical tissue or pushing the obturating material beyond the apex. Nonsurgical approach toward treating such a tooth would necessitate the creation of an apical barrier followed by conventional root canal treatment. Current literature suggests one-step apexification with mineral trioxide aggregate (MTA), with an apical matrix as the treatment of choice. A new calcium silicate-based cement also called as dentine substitute by the manufacturers with good handling properties has been introduced recently by the trade name Biodentine™ (Septodont, St. Maurdes Fossés, France). This case report presents management of a secondary endodontic case with an open apex treated with the concept of 'lesion sterilization and tissue repair (LSTR)' using triantibiotic paste and Biodentine™ for apical barrier formation. A 12-month follow up with cone beam-computed topography (CBCT) exhibited progressive involution of periapical radiolucency with indications of good healing of the periapical tissues and absence of clinical symptoms. PMID:24944456

  6. Cone beam-computed topographic evaluation of a central incisor with an open apex and a failed root canal treatment using one-step apexification with Biodentine™: A case report

    PubMed Central

    Sinha, Nidhi; Singh, Bijay; Patil, Santosh

    2014-01-01

    A symptomatic endodontically treated immature tooth with periapical pathology presents multiple challenges to the clinician. Owing to incomplete root formation, gutta percha removal has to be done carefully without further damaging the periapical tissue or pushing the obturating material beyond the apex. Nonsurgical approach toward treating such a tooth would necessitate the creation of an apical barrier followed by conventional root canal treatment. Current literature suggests one-step apexification with mineral trioxide aggregate (MTA), with an apical matrix as the treatment of choice. A new calcium silicate-based cement also called as dentine substitute by the manufacturers with good handling properties has been introduced recently by the trade name Biodentine™ (Septodont, St. Maurdes Fossés, France). This case report presents management of a secondary endodontic case with an open apex treated with the concept of ‘lesion sterilization and tissue repair (LSTR)’ using triantibiotic paste and Biodentine™ for apical barrier formation. A 12-month follow up with cone beam-computed topography (CBCT) exhibited progressive involution of periapical radiolucency with indications of good healing of the periapical tissues and absence of clinical symptoms. PMID:24944456

  7. The adaptive significance of enamel loss in the mandibular incisors of cercopithecine primates (Mammalia: Cercopithecidae): a finite element modelling study.

    PubMed

    Kupczik, Kornelius; Lev-Tov Chattah, Netta

    2014-01-01

    In several primate groups enamel is reduced or absent from the lingual (tongue) side of the mandibular incisor crowns akin to other placental and marsupial mammalian groups such as rodents, lagomorphs and wombats. Here we investigate the presumed adaptation of crowns with unilateral enamel to the incision of tough foods in cercopithecines, an Old World monkey subfamily, using a simulation approach. We developed and validated a finite element model of the lower central incisor of the rhesus macaque (Macaca mulatta) with labial enamel only to compute three-dimensional displacements and maximum principal stresses on the crown subjected to compressive loads varying in orientation. Moreover, we developed a model of a macaque incisor with enamel present on both labial and lingual aspects, thus resembling the ancestral condition found in the sister taxon, the leaf-eating colobines. The results showed that, concomitant with experimental results, the cercopithecine crown with unilateral enamel bends predominantly towards the inside of the mouth, while displacements decreased when both labial and lingual enamel are present. Importantly, the cercopithecine incisor crown experienced lower maximum principal stress on the lingual side compared to the incisor with enamel on the lingual and labial aspects under non-axial loads directed either towards the inside or outside of the mouth. These findings suggest that cercopithecine mandibular incisors are adapted to a wide range of ingestive behaviours compared to colobines. We conclude that the evolutionary loss of lingual enamel in cercopithecines has conferred a safeguard against crown failure under a loading regime assumed for the ingestion (peeling, scraping) of tough-skinned fruits. PMID:24831704

  8. Management of invasive cervical resorption in a maxillary central incisor

    PubMed Central

    Kumar, S. Senthil; Kumar, N. S. Mohan; Karunakaran, J. V.; Nagendran, S.

    2015-01-01

    Invasive cervical resorption is often not diagnosed properly, leading to improper treatment or unnecessary loss of the tooth structure. Early diagnosis and appropriate treatment are the keys to a successful outcome of therapy. Invasive cervical resorption is often seen in the cervical area of the tooth, but because it is initiated apical to the epithelial attachment, it can present anywhere in the root. In the early stages, it may be symmetrical, but larger lesions have the tendency to be asymmetrical. It can expand apically or coronally. PMID:26538950

  9. Management of internal resorption of central incisor using hybrid technique

    PubMed Central

    Gayathri, Prabakaran; Pandey, Ramesh Kumar; Jain, Eesha

    2014-01-01

    Internal inflammatory root resorption is characterised by progressive destruction of intraradicular dentin and dentinal tubules along the root canal wall. A number of theories have been proposed as a possible cause for internal resorption. It is usually asymptomatic and detected during routine radiographic investigations. Prompt diagnosis and early management of such defects is essential to maintain the integrity of the tooth. Non-surgical and surgical methods are the two main strategies involved in the management of internal resorption. The non-surgical method is usually preferred, but in cases of extensive resorption with external root perforation, surgical intervention has been advocated. The present case illustrates repair of perforating internal resorption by hybrid method, using mineral trioxide aggregate and gutta-percha, following surgical exposure. After a 10-month follow-up, no clinical and radiographic abnormalities were observed. Additionally, there was also marked reduction in periodontal pocket depth. PMID:24473420

  10. Upper incisor to Soft Tissue Plane (UI-STP): a new reference for diagnosis and planning in dentofacial deformities.

    PubMed

    Hernandez-Alfaro, Federico

    2010-09-01

    Planning in orthognathic surgery has been and still is an open issue. We have evolved from 2D classical cephalometric hard-tissue planning to 2D soft tissue planning, and finally to 3D and hard and soft tissue evaluation. This, to our knowledge, is the first description of a new Soft Tissue Plane (STP) and its relationship with the anterior position of the upper incisor (UI). Profile photographs of 110 "attractive individuals" with lips at rest or smiling and with upper incisor shown were used. The photographs used were of 65 professional models from two international agencies and 45 individuals considered most attractive in the internet forums, which included catwalk models and actors. In 86 cases (78.18 %), the incisor was located in front of the STP (A). In 15 cases (13.63%), it was on the plane (N); and in the remaining 9 cases (8.18%), it was behind (P). Despite the limitations of this study and based on our series, we can conclude that the upper incisor is located at or in front of the Soft Tissue Plane (STP) in 91.81% of the attractive facial profiles studied. On the other hand, the relative position of the upper incisor to the soft tissue plane (UI-STP) could be a useful diagnostic and planning tool in orthodontic and surgical management of dentofacial deformities. PMID:20383095

  11. [Agenesis of the maxillary lateral incisors: orthodontic and implant approach].

    PubMed

    Sabri, Roy; Aboujaoude, Nadim

    2008-12-01

    Missing maxillary lateral incisors create a major esthetic problem due to their strategic position in the smile. The two treatment approaches commonly taken are creating adequate space to prosthetically replace the missing lateral incisors or closing the spaces and replacing the missing lateral incisors by the canines. This article will discuss indications, advantages, disadvantages and problems encountered in cases of space opening and space closure for missing laterals. The amount of space to be created, the preparation and the timing for implant placement, the bone volume, the implant size and prosthetic considerations will also be discussed. The methods for reshaping canines and building them up to simulate lateral incisors in orthodontic space closure, and positioning the canines and first premolars - so that they resemble to the teeth they are replacing - will be described. PMID:19061632

  12. Maxillary lateral incisor with two roots: a case report.

    PubMed

    Ravindranath, Mithun; Neelakantan, Prasanna; Subba Rao, C V

    2011-01-01

    Although the dental literature has indicated that 100% of maxillary lateral incisors have a single canal anatomy, it is possible for these teeth to have extra canals. These extra canals must be identified and debrided to prevent endodontic failure. This report presents an uncommon case involving a maxillary lateral incisor with two roots. Even when the frequency of radicular anatomy abnormality is extremely low, dentists must consider the possibility that a tooth has extra root canals or even extra roots. PMID:21613043

  13. [Failure in anterior rehabilitation of agenesic maxillary lateral incisors].

    PubMed

    Le Gall, Michel; Philippart-Rochaix, Martine; Philip-Alliez, Camille

    2016-03-01

    Agenesis of the maxillary lateral incisors poses particular problems for dentists, orthodontists and patients. Treatment of these ageneses is still highly controversial, both functionally and esthetically. The patient's smile and anterior guidance are affected and must be restored. The diagnosis is easy. Few mistakes are possible. However, managing patients with missing maxillary lateral incisors can be a challenge, commonly involving two possible treatment approaches: space opening to replace the missing lateral incisor with a prosthetic unit (denture, bridge or implant) or orthodontic space closure replacing the missing lateral incisor with the maxillary canine camouflaged to mimic the appearance of a lateral incisor. One of these two options will be adopted using multiple means...liable to trigger a multitude of possible errors. Ultimately, optimal results can only be achieved if there is excellent coordination between different practitioners in various specialties. Each clinician will have a specific role to play. Also, the patient and family are at the heart of the decision-making process, by virtue of their consent (treatment duration, financial resources) and their motivation. This multi-factorial, multi-disciplinary decision process means that treatment of the lateral incisor is an ongoing challenge for the clinician striving for the best possible result. Each case is different. No set rules exist. No single factor can be neglected if we are to avoid "failure". PMID:27083223

  14. Onset of molar incisor hypomineralization (MIH).

    PubMed

    Fagrell, Tobias G; Salmon, Phil; Melin, Lisa; Norn, Jrgen G

    2013-01-01

    The etiological factors and timing of the onset of molar incisor hypomineralization (MIH) are still not clear. The aim of this study was to examine ground radial and sagittal sections from teeth diagnosed with MIH using light microscopy, polarized light microscopy and X-ray micro-computed tomography (XMCT) and to estimate the onset and timing of the MIH and to relate the hypomineralized enamel to the incremental lines. Thirteen extracted permanent first molars diagnosed MIH, were analyzed with light microscopy and XMCT. The hypomineralized areas were mainly located in the mesio-buccal cusps, starting at the enamel-dentin-junction and continuing towards the enamel surface. In a relative gray scale analysis the values decreased from the EDJ towards the enamel surface. The findings indicate that the ameloblasts in the hypomineralized enamel are capable of forming an enamel of normal thickness, but with a substantial reduction of their capacity for maturation of enamel. Chronologically, it is estimated that the timing of the disturbance is at a period during the first 6-7 months of age. PMID:23957140

  15. Electron microprobe analyses of Ca, S, Mg and P distribution in incisors of Spacelab-3 rats

    NASA Technical Reports Server (NTRS)

    Rosenberg, G. D.; Simmons, D. J.

    1985-01-01

    The distribution of Ca, S, Mg and P was mapped within the incisors of Spacelab-3 rats using an electron microprobe. The data indicate that Flight rats maintained in orbit for 7 days have significantly higher Ca/Mg ratios in dentin due to both higher Ca and lower Mg content than in dentin of ground-based Controls. There is no statistical difference in distribution of either P or S within Fligth animals and Controls, but there is clear indication that, for P at least, the reason is the greater variability of the Control data. These results are consistent with those obtained on a previous NASA/COSMOS flight of 18.5 days duration, although they are not pronounced. The results further suggest that continuously growing rat incisors provide useful records of the effects of weightlessness on Ca metabolism.

  16. Esthetic and biologic mode of reattaching incisor fracture fragment utilizing glass fiber post

    PubMed Central

    Manju, M.; Shanthraj, Srinivas L.; Savitha, K. C.; Sethi, Ntasha

    2015-01-01

    Trauma to the anterior teeth affects the esthetic and psychological well-being of the patient. Advancement in the adhesive dentistry has facilitated the restoration of the coronal tooth fractures by minimally invasive procedures when the original tooth fragment is available. Reattachment of fractured fragment offers immediate treatment with improved preponderant aesthetics and restoration of function. Here, we describe a case of complicated fracture of the maxillary left immature permanent central incisor, which was treated endodontically followed by esthetic reattachment of the fractured fragment using the glass fiber post. Functional demands and esthetic considerations of the patient were fully met with this biologic mode of fragment reattachment. PMID:26283849

  17. Conventional Treatment of Maxillary Incisor Type III Dens Invaginatus with Periapical Lesion: A Case Report

    PubMed Central

    Borges, Álvaro Henrique; Semenoff Segundo, Alex; Nadalin, Michele Regina; Pedro, Fábio Luís Miranda; da Cruz Filho, Antônio Miranda; Sousa-Neto, Manoel Damião

    2011-01-01

    Dens invaginatus is a developmental dental anomaly clinically characterized by a palatine furrow that can be limited to the coronal pulp or may extend to the radicular apex. The purpose of this paper was to present a clinical case of type III dens invaginatus, identified on the maxillary right central incisor in anterior periapical radiographs, in which the tooth was submitted to conventional endodontic treatment. The results obtained after five years of clinical and radiographic followup demonstrated that conventional endodontic treatment is a clinically viable alternative in cases of type III dens invaginatus. PMID:21991460

  18. 24. INTERIOR OF CENTRAL ROOM. BASE POWER PANEL VISIBLE ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. INTERIOR OF CENTRAL ROOM. BASE POWER PANEL VISIBLE ON RIGHT WALL OF HALLWAY. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  19. Fitness consequences of centrality in mutualistic individual-based networks

    PubMed Central

    Gómez, José M.; Perfectti, Francisco

    2012-01-01

    The relationships among the members of a population can be visualized using individual networks, where each individual is a node connected to each other by means of links describing the interactions. The centrality of a given node captures its importance within the network. We hypothesize that in mutualistic networks, the centrality of a node should benefit its fitness. We test this idea studying eight individual-based networks originated from the interaction between Erysimum mediohispanicum and its flower visitors. In these networks, each plant was considered a node and was connected to conspecifics sharing flower visitors. Centrality indicates how well connected is a given E. mediohispanicum individual with the rest of the co-occurring conspecifics because of sharing flower visitors. The centrality was estimated by three network metrics: betweenness, closeness and degree. The complex relationship between centrality, phenotype and fitness was explored by structural equation modelling. We found that the centrality of a plant was related to its fitness, with plants occupying central positions having higher fitness than those occupying peripheral positions. The structural equation models (SEMs) indicated that the centrality effect on fitness was not merely an effect of the abundance of visits and the species richness of visitors. Centrality has an effect even when simultaneously accounting for these predictors. The SEMs also indicated that the centrality effect on fitness was because of the specific phenotype of each plant, with attractive plants occupying central positions in networks, in relation to the distribution of conspecific phenotypes. This finding suggests that centrality, owing to its dependence on social interactions, may be an appropriate surrogate for the interacting phenotype of individuals. PMID:22158957

  20. Estrogen deficiency reduces the dentinogenic capacity of rat lower incisors.

    PubMed

    Xu, Tao; Yan, Ming; Wang, Yanping; Wang, Zhanwei; Xie, Lizhe; Tang, Chunbo; Zhang, Guangdong; Yu, Jinhua

    2014-02-01

    Endogenous estrogen deficiency usually causes the systemic osteoporosis including the jaw bones. However, it remains unclear whether estrogen deficiency can affect the tooth mineralization. In this study, the classical osteoporotic rat model was established via the ovariectomy, which was subsequently confirmed by the detection of serum estradiol levels and body weights. The mineralization-related assays were performed to observe the potential changes in mineralized tissues of rat lower incisors. The clinical crown length, compressive strength, radiodensity, and calcium content in the ovariectomy group (OVX) were significantly downregulated (P < 0.01), as compared with the sham operation group (Sham). Histological results revealed that OVX incisors presented the thinner predentin structures than Sham incisors. Immunohistochemical staining and western blot assay further demonstrated that the odonto/osteoblast specific proteins (e.g., dentin sialoprotein, runt-related transcription factor 2, osterix, and osteocalcin) in the dentin-pulp complex of OVX incisors were significantly decreased in comparison with Sham counterparts. Together, estrogen deficiency reduces the dentinogenic capacity and calcium deposition in rat incisors, indicating that estrogen plays an important role in the dentinogenesis. PMID:23974864

  1. Characteristics of incisor-premolar hypodontia in families.

    PubMed

    Arte, S; Nieminen, P; Apajalahti, S; Haavikko, K; Thesleff, I; Pirinen, S

    2001-05-01

    Nonsyndromic tooth agenesis is a genetically and phenotypically heterogenous condition. It is generally assumed that different phenotypic forms are caused by different mutated genes. We analyzed inheritance and phenotype of hypodontia and dental anomalies in 214 family members in three generations of 11 probands collected for genetic linkage study on incisor-premolar hypodontia (IPH). Our analysis confirms the autosomal-dominant transmission with reduced penetrance of IPH. The prevalence of hypodontia and/or peg-shaped teeth was over 40% in first- and second-degree relatives and 18% in first cousins of the probands. Four of nine noted obligate carriers of hypodontia gene had dental anomalies, including small upper lateral incisors, ectopic canines, taurodontism, and rotated premolars. These anomalies were also observed at higher than normal frequency in relatives affected with hypodontia. We conclude that incisor-premolar hypodontia is a genetic condition with autosomal-dominant transmission and that it is associated with several other dental abnormalities. PMID:11437217

  2. Glassfiber Post: An Alternative for Restoring Grossly Decayed Primary Incisors

    PubMed Central

    Grover, Rashu

    2012-01-01

    ABSTRACT Restoration of primary incisors, which have been severely damaged by rampant caries or trauma, is a difficult task for the pediatric dentist. With the introduction of new adhesive systems and restorative materials, alternative approaches for treating these teeth have been proposed. This paper discusses the restoration of carious primary maxillary incisors using composite resin restoration reinforced with fiberglass post. Two case reports are presented here to describe the procedure. Over a 1 year period, the crowns have demonstrated good retention and esthetic results. How to cite this article: Mehra M, Grover R. Glassfiber Post: An Alternative for Restoring Grossly Decayed Primary Incisors. Int J Clin Pediatr Dent 2012;5(2):159-162. PMID:25206160

  3. A study on evaluation of center of resistance of maxillary four incisors during simultaneous intrusion and retraction: A finite element study

    PubMed Central

    Aruna, J.

    2014-01-01

    Aim: The aim of this study is to evaluate the center of resistance of maxillary incisors during simultaneous intrusion and retraction. Subjects and Methods: In this study, the following steps were employed namely, (1) Preprocessing - the creation of geometric model, mesh generation and boundary conditions. (2) Postprocessing - the tooth movement and determination of center of resistance. Results: The center of the mid-sagittal plane approximately 6 mm apical and 4 mm posterior to a line perpendicular to the occlusal plane from the labial alveolar crest of the central incisor resistance for the maxillary four incisors was located within the. Conclusion: Finite element is a sound mechanical method of analysis as it was sufficient enough to provide insight into interactions between orthodontic forces, and dental tissues and reliability of this study. Further by using this study clinically, the center of resistance can be precisely located in single rooted tooth during orthodontic treatment. PMID:25210384

  4. Localized periodontal defect associated with unusual furcation involvement on a mandibular incisor.

    PubMed

    Kwon, TaeHyun; Intini, Giuseppe; Kim, David M; Levin, Liran

    2013-10-01

    A localized periodontal defect associated with an unusual furcation on a mandibular central incisor and its treatment sequences are presented. A 54-year-old woman presented with a persistent localized periodontal defect, which was not responsive to nonsurgical periodontal therapy. An exploratory surgery revealed complete through and through furcation involvement on the right mandibular central incisor, resulting in a three-walled infrabony defect. Following thorough mechanical debridement and root planing, the infrabony aspect of the defect was grafted with freeze-dried bone allograft combined with the recombinant human platelet-derived growth factor-BB. The flaps were positioned to enable patient's home care and professional dental cleaning. Follow-up examination revealed uneventful healing and resolution of the infrabony periodontal defect. Clinicians should be aware of this unusual condition and consider it as a potential etiology when dealing with a persistent localized periodontal defect in the mandibular anterior sextant, which may not respond to the conventional nonsurgical periodontal therapy. Eliminating the active disease as well as enabling careful maintenance and oral hygiene may prevent further deterioration and result in a stable long-term outcome preserving the compromised tooth. PMID:23878844

  5. Management of Ectopically Erupting Maxillary Incisors: A Case Series

    PubMed Central

    Suresh, Kotumachagi Sangappa; Uma, HL; Nagarathna, J

    2015-01-01

    ABSTRACT Eruption disturbances related to the position include ectopic eruption and transpositions. The occurrence of ectopic eruption is most commonly associated with maxillary incisors. The normal eruption, position and morphology of these teeth are crucial to craniofacial development, facial esthetics as well as phonetics. It is essential that the clinicians have thorough knowledge of the eruption disturbances in order to make an appropriate, as well as timely intervention, as dictated by the complexity of the problem. How to cite this article: Suresh KS, Uma HL, Nagarathna J, Kumar P. Management of Ectopically Erupting Maxillary Incisors: A Case Series. Int J Clin Pediatr Dent 2015;8(3):227-233. PMID:26604543

  6. Management of Ectopically Erupting Maxillary Incisors: A Case Series.

    PubMed

    Suresh, Kotumachagi Sangappa; Uma, H L; Nagarathna, J; Kumar, Pravin

    2015-01-01

    Eruption disturbances related to the position include ectopic eruption and transpositions. The occurrence of ectopic eruption is most commonly associated with maxillary incisors. The normal eruption, position and morphology of these teeth are crucial to craniofacial development, facial esthetics as well as phonetics. It is essential that the clinicians have thorough knowledge of the eruption disturbances in order to make an appropriate, as well as timely intervention, as dictated by the complexity of the problem. How to cite this article: Suresh KS, Uma HL, Nagarathna J, Kumar P. Management of Ectopically Erupting Maxillary Incisors: A Case Series. Int J Clin Pediatr Dent 2015;8(3):227-233. PMID:26604543

  7. A new algorithm CNM-Centrality of detecting communities based on node centrality

    NASA Astrophysics Data System (ADS)

    Hu, Fang; Liu, Yuhua

    2016-03-01

    The discovery and analysis of community structure in complex networks is a hot issue in recent years. In this paper, based on the fast greedy clustering algorithm CNM with the thought of local search, the introduction of the idea of node centrality and the optimal division of the central nodes and their neighbor nodes into correct communities, a new algorithm CNM-Centrality of detecting communities in complex networks is proposed. In order to verify the accuracy and efficiency of this algorithm, the performance of this algorithm is tested on several representative real-world networks and a set of computer-generated networks by LFR-benchmark. The experimental results indicate that this algorithm can identify the communities accurately and efficiently. Furthermore, this algorithm can also acquire higher values of modularity and NMI than the CNM, Infomap, Walktrap algorithms do.

  8. a New Centrality Metric Based on Clustering Coefficient

    NASA Astrophysics Data System (ADS)

    Li, Chong; Guo, Shi-Ze; Lu, Zhe-Ming; Qiao, Yu-Long; Song, Guang-Hua

    2013-07-01

    Many centrality metrics have been proposed over the years to compute the centrality of nodes, which has been a key issue in complex network analysis. The most important node can be estimated through a variety of metrics, such as degree, closeness, eigenvector, betweenness, flow betweenness, cumulated nominations and subgraph. Simulated flow is a common method adopted by many centrality metrics, such as flow betweenness centrality, which assumes that the information spreads freely in the entire network. Generally speaking, the farther the information travels, the more times the information passes the geometric center. Thus, it is easy to determine which node is more likely to be the center of the geometry network. However, during information transmission, different nodes do not share the same vitality, and some nodes are more active than others. Therefore, the product of one node's degree and its clustering coefficient can be viewed as a good factor to show how active this node is. In this paper, a new centrality metric called vitality centrality is introduced, which is only based on this product and the simulated flow. Simulation experiments based on six test networks have been carried out to demonstrate the effectiveness of our new metric.

  9. Talon cusps occurring concurrently with dens invaginatus on a permanent maxillary lateral incisor: a case report and literature review.

    PubMed

    Colak, Hakan; Yilmaz, Cicek; Keklik, Hakan; Colak, Tugba

    2014-01-01

    A talon cusp is a prominent accessory horn-like structure that projects from the cingulum or cementoenamel junction of the maxillary or mandibular teeth. It can occur in primary and permanent dentition and can lead to occlusal interference, irritation of the tongue, pulpal necrosis, caries, and periodontal problems. Talon cusp has been reported to affect both sexes, and may be unilateral or bilateral. Talon cusps occur most often on the palatal surface of permanent maxillary incisors. A comprehensive literature review revealed only 6 reported cases of facial talon cusps. A talon cusp occurring simultaneously with dens invaginatus in a tooth is extremely rare; to date, only 9 case reports have been published. This article presents a unique case of concurrent dens invaginatus and palatal and facial talon cusps in the right maxillary central incisor of a 12-year-old girl. PMID:24784523

  10. Nonsurgical Endodontic Management of a Molar-Incisor Malformation-affected Mandibular First Molar: A Case Report.

    PubMed

    Yue, Wonyoung; Kim, Euiseong

    2016-04-01

    A molar-incisor malformation (MIM) is a newly reported type of dental anomaly that involves a characteristic root malformation in permanent first molars and deciduous second molars and a crown defect in permanent central incisors. This case report describes a nonsurgical root canal treatment of a MIM-affected molar by aid of a reformatted axial view of the tooth cone-beam computed tomography (CBCT). A MIM-affected molar has calcified canal orifices and a few immature accessory furcal canals. Conventional root canal treatment with the aid of CBCT followed by resin restoration was performed on the tooth. The malformed roots of MIM teeth generally make it difficult to apply conventional endodontic treatment; however, it was possible to do with the aid of the reformatted axial view of the CBCT. PMID:26706790

  11. Mouse Incisor Stem Cell Niche and Myb Transcription Factors.

    PubMed

    Svandova, E; Vesela, B; Smarda, J; Hampl, A; Radlanski, R J; Matalova, E

    2015-10-01

    Dental hard tissues are formed particularly by odontoblasts (dentin) and ameloblasts (enamel). Whereas the reparation of dentin is often observed, enamel does not regenerate in most species. However, in mouse incisor, a population of somatic stem cells in the cervical loop is responsible for the incisor regeneration. Understanding of the specificities of these cells is therefore of an interest in basic research as well as regenerative therapies. The Myb transcription factors are involved in essential cellular processes. B-Myb is often linked to the stem cell phenotype, and c-Myb expression marks undifferentiated and proliferating cells such as the stem cells. In the presented study, temporo-spatial expression of B-Myb and c-Myb proteins was correlated with localisation of putative somatic stem cells in the mouse incisor cervical loop by immunohistochemistry. B-Myb expression was localised mostly in the zone of transit-amplifying cells, and c-Myb was found in the inner enamel epithelium, the surrounding mesenchyme and in differentiated cells. Taken together, neither B-Myb nor c-Myb was exclusively present or abundant in the area of the incisor stem cell niche. Their distribution, however, supports recently reported novel functions of c-Myb in differentiation of hard tissue cells. PMID:25182175

  12. Continuous and Short Fiber Reinforced Composite in Root Post-Core System of Severely Damaged Incisors

    PubMed Central

    Garoushi, Sufyan; Vallittu, Pekka K; Lassila, Lippo V.J

    2009-01-01

    Purpose: The aim of this study was to determine the static load-bearing capacity of endodontically treated maxillary incisors restored with post-core complex made of experimental fiber composite resin (FC) and complete crown made of particulate filler composite (PFC). Further aim was to evaluate the effect of FC resin on the failure mode of the restoration. Material and Methods: The experimental composite resin (FC) was prepared by mixing 22.5 wt% of short E-glass fibers (3 mm in length) and 22.5 wt% of semi-interpenetrating polymer network (IPN) resin with 55 wt% of silane treated silica fillers. Thirty extracted sound upper central incisors were used. Twenty teeth were prepared by cutting the clinical crown 2 mm above the cemento-enamel junction horizontally. Restorations were made by two techniques (n=10). Group A (control group) contained samples of sound incisor teeth. Group B had teeth restored using glass fiber post (everStick, Stick- Teck) and PFC (Filtek Z250, 3M-ESPE) to build up core and complete crown. In Group C, the teeth were restored with FC as post-core and complete crown of PFC. The root canals were prepared and posts were cemented with a dual cure resin cement. The restorations were polymerized with a hand-light curing unit. All restored teeth were stored in water at room temperature for 24 h before they were statically loaded with speed of 1.0 mm/min until fracture. Data were analyzed using ANOVA (p=0.05). Failure modes were visually examined. Results: ANOVA revealed that restored incisors (Group B and C) had a statistically significantly lower load-bearing capacity (p<0.05) than the control group. Restorations made from FC post-core and PFC coverage (Group C) gave force value of 363 N (112 SD), which was higher than the value of Group B (211 N, 50 SD). Conclusions: Within the limitations of this study, the teeth restored with experimental fiber composite post-core demonstrated higher load bearing capacity than those with fiber post and PFC core. PMID:19444342

  13. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha.

    PubMed

    Mothé, Dimila; Ferretti, Marco P; Avilla, Leonardo S

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans. PMID:26756209

  14. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha

    PubMed Central

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans. PMID:26756209

  15. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens

    PubMed Central

    Sidiq, Mohsin; Bhat, Manohar; Sharma, Rajesh; Bhargava, Neha; Ganta, Shravani

    2015-01-01

    ABSTRACT The aim of this case study was to report a potentially convenient approach instead of a conventional orthodontic procedure for correcting severe rotation of anterior tooth of an 11-year-old Indian boy, with a mixed dentition class I malocclusion. The child reported seeking treatment for severely rotated upper right central incisor with mesiodens and a single tooth crossbite. The supernumerary tooth was first extracted and bondable buttons were placed on the rotated tooth, an appliance composed of a removable plate with Adam’s clasp with distal extension and a loop for engagement of elastics was delivered. Circumferential supracrestal fibrotomy was performed on the corrected derotated tooth. Then, Hawley’s appliance with a z-spring and posterior bite plane was fabricated and placed for correction of crossbite. Thus, this removable appliance can be a simplified and a cost-effective treatment alternative for derotation of anterior tooth, especially during the mixed dentition period. How to cite this article: Sidiq M, Yousuf A, Bhat M, Sharma R, Bhargava N, Ganta S. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens. Int J Clin Pediatr Dent 2015;8(3):234-238. PMID:26604544

  16. Structure–function relations of primate lower incisors: a study of the deformation of Macaca mulatta dentition using electronic speckle pattern interferometry (ESPI)

    PubMed Central

    Chattah, Netta Lev-Tov; Kupczik, Kornelius; Shahar, Ron; Hublin, Jean-Jacques; Weiner, Steve

    2011-01-01

    Teeth adopt a variety of different morphologies, each of which is presumably optimized for performing specific functions during feeding. It is generally agreed that the enamel cap is a crucial element in controlling the mechanical behavior of mammalian teeth under load. Incisors are particularly interesting in terms of structure–function relations, as their role in feeding is that of the ‘first bite’. However, little is known how incisor cap morphology is related to tooth deformation. In the present paper we examine the mechanical behavior of mandibular central incisors in the cercopithecine primate Macaca mulatta under loads similar to those encountered during ingestion. We map three-dimensional displacements on the labial surface of the crown as it is compressed, using electronic speckle pattern interferometry (ESPI), an optical metrology method. In addition, micro-computed tomography is used to obtain data regarding the morphology of the enamel cap, which in the M. mulatta lower incisors exhibits missing or very little enamel on the lingual face. The results showed that although compressed along a longitudinal axis, deformation in the incisors mostly occurred in the lingual direction and orthogonal to the direction of the applied load. Both isolated, embedded teeth and teeth in the mandible showed considerable lingual deformation. Incisor deformation in the mandible was generally greater, reflecting the additional freedom of movement enabled by the supporting structures. We show that the association with adjacent teeth in the arch is significant for the behavior of the tooth under load. Finally, loading two teeth simultaneously in the mandible showed that they work as one functional unit. We suggest that these results demonstrate the importance of enamel cap morphology in directing deformation behavior; an ability stemming from the stiffness of the enamel cap overlying the more pliable dentin. PMID:20408905

  17. Adenomatoid odontogenic tumor associated with an unerupted mandibular lateral incisor: a case report

    PubMed Central

    2015-01-01

    Adenomatoid odontogenic tumor (AOT) is a rare, benign odontogenic tumor that predominantly appears in the second decade of life in female patients. Most AOTs occur in the anterior part of the maxilla and are usually associated with impacted anterior teeth. There are three types of AOT, follicular, extrafollicular, and peripheral, which are classified based on the location of the lesion and its association with the impacted tooth. We report a rare case of AOT associated with an impacted right mandibular lateral incisor in an 11-year-old female patient. PMID:26734563

  18. Adenomatoid odontogenic tumor associated with an unerupted mandibular lateral incisor: a case report.

    PubMed

    Seo, Won-Gyo; Kim, Chul-Hwan; Park, Hae-Seo; Jang, Jong-Won; Chung, Woo-Yeol

    2015-12-01

    Adenomatoid odontogenic tumor (AOT) is a rare, benign odontogenic tumor that predominantly appears in the second decade of life in female patients. Most AOTs occur in the anterior part of the maxilla and are usually associated with impacted anterior teeth. There are three types of AOT, follicular, extrafollicular, and peripheral, which are classified based on the location of the lesion and its association with the impacted tooth. We report a rare case of AOT associated with an impacted right mandibular lateral incisor in an 11-year-old female patient. PMID:26734563

  19. Two betweenness centrality measures based on Randomized Shortest Paths.

    PubMed

    Kivimäki, Ilkka; Lebichot, Bertrand; Saramäki, Jari; Saerens, Marco

    2016-01-01

    This paper introduces two new closely related betweenness centrality measures based on the Randomized Shortest Paths (RSP) framework, which fill a gap between traditional network centrality measures based on shortest paths and more recent methods considering random walks or current flows. The framework defines Boltzmann probability distributions over paths of the network which focus on the shortest paths, but also take into account longer paths depending on an inverse temperature parameter. RSP's have previously proven to be useful in defining distance measures on networks. In this work we study their utility in quantifying the importance of the nodes of a network. The proposed RSP betweenness centralities combine, in an optimal way, the ideas of using the shortest and purely random paths for analysing the roles of network nodes, avoiding issues involving these two paradigms. We present the derivations of these measures and how they can be computed in an efficient way. In addition, we show with real world examples the potential of the RSP betweenness centralities in identifying interesting nodes of a network that more traditional methods might fail to notice. PMID:26838176

  20. Two betweenness centrality measures based on Randomized Shortest Paths

    NASA Astrophysics Data System (ADS)

    Kivimäki, Ilkka; Lebichot, Bertrand; Saramäki, Jari; Saerens, Marco

    2016-02-01

    This paper introduces two new closely related betweenness centrality measures based on the Randomized Shortest Paths (RSP) framework, which fill a gap between traditional network centrality measures based on shortest paths and more recent methods considering random walks or current flows. The framework defines Boltzmann probability distributions over paths of the network which focus on the shortest paths, but also take into account longer paths depending on an inverse temperature parameter. RSP’s have previously proven to be useful in defining distance measures on networks. In this work we study their utility in quantifying the importance of the nodes of a network. The proposed RSP betweenness centralities combine, in an optimal way, the ideas of using the shortest and purely random paths for analysing the roles of network nodes, avoiding issues involving these two paradigms. We present the derivations of these measures and how they can be computed in an efficient way. In addition, we show with real world examples the potential of the RSP betweenness centralities in identifying interesting nodes of a network that more traditional methods might fail to notice.

  1. Two betweenness centrality measures based on Randomized Shortest Paths

    PubMed Central

    Kivimäki, Ilkka; Lebichot, Bertrand; Saramäki, Jari; Saerens, Marco

    2016-01-01

    This paper introduces two new closely related betweenness centrality measures based on the Randomized Shortest Paths (RSP) framework, which fill a gap between traditional network centrality measures based on shortest paths and more recent methods considering random walks or current flows. The framework defines Boltzmann probability distributions over paths of the network which focus on the shortest paths, but also take into account longer paths depending on an inverse temperature parameter. RSP’s have previously proven to be useful in defining distance measures on networks. In this work we study their utility in quantifying the importance of the nodes of a network. The proposed RSP betweenness centralities combine, in an optimal way, the ideas of using the shortest and purely random paths for analysing the roles of network nodes, avoiding issues involving these two paradigms. We present the derivations of these measures and how they can be computed in an efficient way. In addition, we show with real world examples the potential of the RSP betweenness centralities in identifying interesting nodes of a network that more traditional methods might fail to notice. PMID:26838176

  2. Sex determination using the mesio-distal dimension of permanent maxillary incisors and canines in a modern Chilean population.

    PubMed

    Peckmann, Tanya R; Logar, Ciara; Garrido-Varas, Claudia E; Meek, Susan; Pinto, Ximena Toledo

    2016-03-01

    The pelvis and skull have been shown to be the most accurate skeletal elements for the determination of sex. Incomplete or fragmentary bones are frequently found at forensic sites however teeth are often recovered in forensic cases due to their postmortem longevity. The goal of the present research was to investigate sexual dimorphism between the mesio-distal dimension of the permanent maxillary incisors and canines for the determination of sex in a contemporary Chilean population. Three hundred and three dental models (126 males and 177 females) from individuals ranging in age from 13years to 37years old were used from the School of Dentistry, University of Chile. The statistical analyses showed that only the central incisors and canines were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 59.7% to 65.0% for the univariate analysis and 60.1% to 66.7% for the multivariate analysis. Comparisons to other populations were made. Overall, the accuracies ranged from 54.4% to 63.3% with males most often identified correctly and females most often misidentified. The determination of sex from the mesio-distal width of incisors and canines in Chilean populations does not adhere to the Mohan and Daubert criteria and therefore would not be presented as evidence in court. PMID:26976465

  3. Structural and Morphometric Comparison of Lower Incisors in PACAP-Deficient and Wild-Type Mice.

    PubMed

    Sandor, B; Fintor, K; Reglodi, D; Fulop, D B; Helyes, Z; Szanto, I; Nagy, P; Hashimoto, H; Tamas, A

    2016-06-01

    Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with widespread distribution. PACAP plays an important role in the development of the nervous system, it has a trophic and protective effect, and it is also implicated in the regulation of various physiological functions. Teeth are originated from the mesenchyme of the neural crest and the ectoderm of the first branchial arch, suggesting similarities with the development of the nervous system. Earlier PACAP-immunoreactive fibers have been found in the odontoblastic and subodontoblastic layers of the dental pulp. Our previous examinations have shown that PACAP deficiency causes alterations in the morphology and structure of the developing molars of 7-day-old mice. In our present study, morphometric and structural comparison was performed on the incisors of 1-year-old wild-type and PACAP-deficient mice. Hard tissue density measurements and morphometric comparison were carried out on the mandibles and the lower incisors with micro-CT. For structural examination, Raman microscopy was applied on frontal thin sections of the mandible. With micro-CT morphometrical measurements, the size of the incisors and the relative volume of the pulp to dentin were significantly smaller in the PACAP-deficient group compared to the wild-type animals. The density of calcium hydroxyapatite in the dentin was reduced in the PACAP-deficient mice. No structural differences could be observed in the enamel with Raman microscopy. Significant differences were found in the dentin of PACAP-deficient mice with Raman microscopy, where increased carbonate/phosphate ratio indicates higher intracrystalline disordering. The evaluation of amide III bands in the dentin revealed higher structural diversity in wild-type mice. Based upon our present and previous results, it is obvious that PACAP plays an important role in tooth development with the regulation of morphogenesis, dentin, and enamel mineralization. Further studies are required to clarify the molecular background of the effects of PACAP on tooth development. PMID:27154515

  4. A Rare Occurrence of Geminated-Taloned Maxillary Lateral Incisor

    PubMed Central

    Kayal, Vizhi G

    2012-01-01

    ABSTRACT The talon cusp is a developmental anomaly characterized by the presence of an accessory cusp like structure projecting from the cingulum area of the anterior teeth. Gemination is an anomaly caused by a single tooth germ that attempted to divide during its development. These developmental anomalies may cause clinical problems including esthetic impairment, pain, caries and tooth crowding. Co-occurrence of two anomalies in a teeth is rare. This paper presents an unusual case of talon cusp on geminated permanent lateral incisor. How to cite this article: Neeraja R, Kayal VG. A Rare Occurrence of Geminated-Taloned Maxillary Lateral Incisor. Int J Clin Pediatr Dent 2012;5(2):136-138. PMID:25206153

  5. A rare occurrence of geminated-taloned maxillary lateral incisor.

    PubMed

    Neeraja, R; Kayal, Vizhi G

    2012-05-01

    The talon cusp is a developmental anomaly characterized by the presence of an accessory cusp like structure projecting from the cingulum area of the anterior teeth. Gemination is an anomaly caused by a single tooth germ that attempted to divide during its development. These developmental anomalies may cause clinical problems including esthetic impairment, pain, caries and tooth crowding. Co-occurrence of two anomalies in a teeth is rare. This paper presents an unusual case of talon cusp on geminated permanent lateral incisor. How to cite this article: Neeraja R, Kayal VG. A Rare Occurrence of Geminated-Taloned Maxillary Lateral Incisor. Int J Clin Pediatr Dent 2012;5(2):136-138. PMID:25206153

  6. A comparative study of mandibular incisor relation to the lingual frenum in natural dentition and in complete denture wearers.

    PubMed

    Parimala, B K; Prithviraj, D R

    2012-12-01

    The determination of the occlusal vertical dimension and proper positioning of the anterior teeth are major factors in making complete dentures which will give optimum service. In this study, efforts were made to evaluate the reliability of measurement of vertical distance between the anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors in natural dentition among different age groups and in complete denture wearers. Three hundred dentulous subjects belonging to different age groups and hundred edentulous patients wearing complete dentures were selected. The dentulous group was divided into three groups, group I (20-40 years), group II (41-60 years), group III (61 years and above) and the edentulous subjects being group IV ( 40-60 years). Mandibular irreversible hydrocolloid impression (Alginate) was made using modified stock tray. In edentulous subjects impression was made with denture in position. The vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors was measured on the dentulous casts and casts of complete denture wearer using dental surveyor and the vernier calipers. The values were tabulated and statistically analysed. The mean vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors among dentulous subjects was 12.3 mm and among complete denture wearers was found to be 13.2 mm. There was no significant variation in the mean vertical distance among dentulous subjects belonging to different age groups. At 5 % significance level, statistically there was a significant difference in the mean vertical distance between group I and group IV; group II and group IV. PMID:24293917

  7. Reversed palatal perforation by upper incisors in ageing blind mole-rats (Spalax ehrenbergi)

    PubMed Central

    ZURI, I.; TERKEL, J.

    2001-01-01

    Blind mole-rats (Spalax ehrenbergi) are fossorial solitary rodents that present striking morphological, physiological and behavioural adaptations to the subterranean environment in which they live. Previous studies have shown that mole-rats are specialised in tooth-digging. The rapid eruption-rate of their incisors has evolved to compensate for their excessive wear by excavation. Males use their incisors more than females for digging and fighting, and their rate of incisor eruption is significantly more rapid than in females. Since mole-rats use their incisors for digging throughout the year, we suggest that continuous mechanical pressure on their oral tissues concentrated at the apical sites of the upper incisors leads to cell and tissue fatigue. We provide evidence for 5 stages of palatal perforation by the upper incisors at their apical sites, with maximum perforation characterising aged males. Interspecies comparisons with 7 other fossorial and semi-fossorial rodent species, and with beavers, which expose their incisors to enormous mechanical pressure, revealed that this palatal perforation is unique to the male mole-rat. We suggest that while the fast eruption rate of incisors in the mole-rat compensates for the rapid wear resulting from digging, evolutionary adaptation to continuous tooth-digging is still ongoing, since the physical pressure of digging at the apical sites of the upper incisors leads to tissue destruction, breakage of the palatal bone and possibly to death, as a result of maxillary inflammation. PMID:11760890

  8. Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion*

    PubMed Central

    Guo, Qing-yuan; Zhang, Shi-jie; Liu, Hong; Wang, Chun-ling; Wei, Fu-lan; Lv, Tao; Wang, Na-na; Liu, Dong-xu

    2011-01-01

    Objective: The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage. Methods: Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted. Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion. A computed tomography (CT) scan was performed after placement of the miniscrews and treatment. The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone. Results: The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm, respectively, and (1.34±0.74) mm of upper central incisor intrusion. Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm, respectively, and the percentages were (6.49±3.54)% and (27.42±9.77)%, respectively. The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°, respectively. Conclusions: Thus, for adult patients with bimaxillary protrusion, mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion. Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss. PMID:22135148

  9. Case report: A medieval case of molar-incisor-hypomineralisation.

    PubMed

    Curzon, M E J; Ogden, A R; Williams-Ward, M; Cleaton-Jones, P E

    2015-12-18

    Introduction Molar-incisor-hypomineralisation (MIH) has been identified in recent years as a condition affecting the first permanent molars and, in some cases, the permanent incisors. Many factors have been suggested as to its aetiology. Examples of MIH have also been reported in skeletal remains in the past. These historical examples have, however, been for unknown individuals.Case report A skull that has become available for dental examination that is uncertainly attributed to be that of Lady Eleanor Talbot (c.1436-1468) who ended her life as a Carmelite nun in Norwich (England). The dental findings of the examination showed enamel defects of molar teeth 36 and 46, as well as small areas on other molars, and striations of the enamel of permanent anterior teeth consistent with MIH. There is exposure of the roots of some maxillary teeth with resultant root caries. The presence of areas of enamel decalcification commensurate with 'Turner teeth' on 43 and 44 indicates that there were likely to have been periapical abscesses secondary to dental caries of the primary teeth. In addition, there is occlusal wear of all of teeth with extensive calculus and periodontal exposure of the roots of the mandibular incisors. Failed development or very early ante-mortem loss of premolars 15 and 25 is evident, as well as evidence in the same region of a large abscess cavity with extensive maxillary bone destruction. Healing cribra orbitalia, porosity, which is considered to be an indicator of nutritional stress, is visible on the superior aspect of the left orbit.Conclusion A case of MIH is reported in a skull dating from the mid-15th century. PMID:26679138

  10. A web-based central diagnostic data repository.

    PubMed

    Müller, Thomas H; Adelhard, Klaus

    2002-01-01

    A central repository for diagnostic information about individual patients was created as a service to diagnostic laboratories participating in the Compentence Network for Acute and Chronic Leukemias in order to support health care delivery to patients suffering from leukemia. During the diagnostic phase several specialised laboratories perform different assays on samples from the same patient. The use of these assays in the diagnostic process and during the treatment phase may be improved in terms of both rapid delivery and cost if any one laboratory is aware of preliminary or final results from the assay carried out in other laboratories. In order to support a more efficient communication of these results, a central diagnostic data repository (CDDR) was created and web-based user interface was developed. Currently, the CDDR maintains documents in the form of portable document format (PDF) files. Several other formats are accepted and converted automatically upon entry. Patient identification is accomplished by pseudonym rather than proper name and the data is held on the CDDR for a limited time interval to accommodate the stringent privacy regulations in Germany. The principle operation of a CDDR may also be applied to the diagnostic or therapeutic process of other diseases. PMID:15460696

  11. Agenesis of lateral incisors: A fresh look at our practice.

    PubMed

    Muller, Christine

    2015-12-01

    In cases involving compensation treatment for edentulousness related to agenesis of the lateral incisors, the transition phase between the orthodontic and the prosthetic stages is tricky. Using clinical illustrations, we will demonstrate that it is time we took a fresh look at our practices. The aim will be to shorten this phase either by postponing the orthodontic stage into adulthood or by placing the prosthesis as quickly as possible on completion of the orthodontic stage, a process which is now feasible, thanks to advances in the designing of bonded bridges and notably of cantilever bonded bridges. PMID:26527037

  12. Effects of centrality on retrieval of text-based concepts.

    PubMed

    Albrecht, J E; O'Brien, E J

    1991-09-01

    Four experiments examined the effect of centrality on retrieval time using a wide range of testing conditions. Subjects read passages containing concepts that were rated as central, moderately central, or peripheral to a passage, and then were asked to retrieve those concepts. Experiment 1 used a probe recognition task that contained foils that were unrelated to the passage, and it was found that central concepts were recognized more quickly than peripheral concepts. In Experiment 2, the foils were passage related, resulting in a much larger recognition advantage of central concepts over peripheral concepts. Experiment 3 used a speeded-recall task. Again central concepts were recalled more quickly than less central concepts. Experiment 4 ruled out a simple strength argument. The results of all four experiments are discussed in terms of text being represented as an integrated network. Within this network, central concepts are more interconnected, providing additional access routes that facilitate retrieval. PMID:1834774

  13. Non-linear viscoelastic finite element analysis of the effect of the length of glass fiber posts on the biomechanical behaviour of directly restored incisors and surrounding alveolar bone.

    PubMed

    Ferrari, Marco; Sorrentino, Roberto; Zarone, Fernando; Apicella, Davide; Aversa, Raffaella; Apicella, Antonio

    2008-07-01

    The study aimed at estimating the effect of insertion length of posts with composite restorations on stress and strain distributions in central incisors and surrounding bone. The typical, average geometries were generated in a FEA environment. Dentin was considered as an elastic orthotropic material, and periodontal ligament was coupled with nonlinear viscoelastic mechanical properties. The model was then validated with experimental data on displacement of incisors from published literature. Three post lengths were investigated in this study: root insertion of 5, 7, and 9 mm. For control, a sound incisor model was generated. Then, a tearing load of 50 N was applied to both sound tooth and simulation models. Post restorations did not seem to affect the strain distribution in bone when compared to the control. All simulated post restorations affected incisor biomechanics and reduced the root's deforming capability, while the composite crowns underwent a higher degree of deformation than the sound crown. No differences could be noticed in incisor stress and strain. As for the influence of post length, it was not shown to affect the biomechanics of restored teeth. PMID:18833761

  14. Survival rate and fracture strength of incisors restored with different post and core systems and endodontically treated incisors without coronoradicular reinforcement.

    PubMed

    Pontius, Oliver; Nathanson, D; Giordano, R; Schilder, H; Hutter, Jeffrey W

    2002-10-01

    This in vitro study evaluated the survival rate and fracture resistance of maxillary central incisors restored with different post and core systems. The post and core systems investigated were a prefabricated high precious metal post with cast core (group A), zirconia post with a prefabricated bonded ceramic core (group B), and a resin-ceramic interpenetrating phase composite post (experimental) with a prefabricated bonded ceramic core (group C). The all-ceramic copings were cemented using Panavia 21 TC. In the group without coronoradicular reinforcement, the access cavity was closed with a light-cured composite in combination with a dentine-bonding agent (group D). Each specimen was intermittently loaded and thermocycled before final stress tests in a Zwick machine. The survival rates after 1,200,000 cycles in the artificial mouth were 90% (group A), 80% (group B), 60% (group C), and 100% (group D). Statistically significant differences were found between all groups with the exception of A and B, when failure during cyclic loading was included (Kruskal-Wallis multiple comparisons test). Samples restored with a cast post and core demonstrated more vertical root fractures. It was concluded that the preservation of both internal and external tooth structure is of utmost importance when restoring endodontically treated teeth. PMID:12398170

  15. Lower incisor extraction treatment with the Invisalign® technique: three case reports.

    PubMed

    Giancotti, Aldo; Garino, Francesco; Mampieri, Gianluca

    2015-03-01

    The extraction of a lower incisor can lead to satisfactory orthodontic results for patients with moderate to severe lower incisor crowding. Invisalign(®) is a treatment modality for such treatments, moving teeth with precision and reducing inconvenience for the patient. Three case reports are presented in this article supporting the above statements. PMID:25808381

  16. A cross-sectional clinical study on shape of nose inner-canthal distance and geometric progression as predictors for width of the maxillary incisor teeth

    PubMed Central

    Reddy, Naveen; Singh, T. Rajesh; Reddy, Swetha; Guruprasad, Yadavalli

    2014-01-01

    Objectives: The objective of this study is to evaluate the relationship of anatomical landmarks of the face and geometric progression as predictors for the width of the maxillary incisor teeth. Materials and Methods: The central incisor width (CIW), lateral incisor width (LIW), inner-canthal distance (ICD) and inter-alar distance (IAD) from a total of 150 subjects were measured clinically. The width of the root of the nose (WRN) was measured on standard photographs of the subjects. Student t-test has been used to find the significance of parameters between male and female. Pearson correlation has been used to find any relation of the parameters. Results: The IAD and the WRN measurements suggest that the shape of the nose is wider and more triangular in males. The mean maxillary CIW and ICD was significantly higher in males than females. Conclusion: The proportion of IAD to WRN seems to be a reliable guide for deciding the proportion of the maxillary central and LIW. The ICD, when multiplied by a decreasing function value of the geometric progression term 0.618 and divided by 2, was a reliable predictor of the maxillary CIW. PMID:25097395

  17. Enamel-free teeth: Tbx1 deletion affects amelogenesis in rodent incisors

    PubMed Central

    Catón, Javier; Luder, Hans-Ulrich; Zoupa, Maria; Bradman, Matthew; Bluteau, Gilles; Tucker, Abigail S.; Klein, Ophir; Mitsiadis, Thimios A.

    2010-01-01

    TBX1 is a principal candidate gene for DiGeorge syndrome, a developmental anomaly that affects the heart, thymus, parathyroid, face, and teeth. A mouse model carrying a deletion in a functional region of the Tbx1 gene has been extensively used to study anomalies related to this syndrome. We have used the Tbx1 null mouse to understand the tooth phenotype reported in patients afflicted by DiGeorge syndrome. Because of the early lethality of the Tbx1−/− mice, we used long-term culture techniques that allow the unharmed growth of incisors until their full maturity. All cultured incisors of Tbx1−/− mice were hypoplastic and lacked enamel, while thorough histological examinations demonstrated the complete absence of ameloblasts. The absence of enamel is preceded by a decrease in proliferation of the ameloblast precursor cells and a reduction in amelogenin gene expression. The cervical loop area of the incisor, which contains the niche for the epithelial stem cells, was either severely reduced or completely missing in mutant incisors. In contrast, ectopic expression of Tbx1 was observed in incisors from mice with upregulated Fibroblast Growth Factor signalling and was closely linked to ectopic enamel formation and deposition in these incisors. These results demonstrate that Tbx1 is essential for the maintenance of ameloblast progenitor cells in rodent incisors and that its deletion results in the absence of enamel formation. PMID:19233155

  18. Notching and anterior beveling on fossil horse incisors: Indicators of domestication?

    NASA Astrophysics Data System (ADS)

    Rogers, Richard A.; Rogers, Laurine A.

    1988-01-01

    One of the lines of evidence cited for possible late Pleistocene human control of horses has been the presence of notching and anterior beveling on horse incisor teeth recovered from upper and middle Paleolithic sites in Europe. Similar forms of wear have been found on the incisor teeth of wild horses from early and middle Pleistocene deposits in North America. Notching appears partly due to malocclusion and chipping. The causes of beveling are less certain but may involve the eating of bark. Therefore, the presence of notching and anterior beveling on horse incisor teeth may not be a reliable indicator of human control.

  19. Alternative treatment modalities for immature intruded permanent incisors: report of 2 cases.

    PubMed

    Gondim, Juliana Oliveira; Diniz, Michele Baffi; de Abreu-e-Lima, Fbio Cesar Braga; Pansani, Cyneu Aguiar; Moreira Neto, Jos Jeov Siebra

    2009-01-01

    Intrusion of permanent teeth is one of the most severe types of traumatic injuries. Different treatment strategies have been proposed, and the best approach for each case depends on the stage of root development, severity of the intrusive luxation, presence of alveolar fracture and number of intruded teeth. The purpose of this paper is to describe the treatment management of 2 cases of severely intruded immature permanent maxillary central incisors in 7 1/2- and 8-year-old children. In case 1, the traumatized tooth was treated by surgical repositioning, while in case 2 watchful waiting for spontaneous re-eruption was the treatment of choice. Treatment strategies were successful in both cases, as demonstrated by the continuation of root development, maintenance of pulp vitality, and absence of signs of periapical pathosis during the follow-up period. Regardless of the treatment strategy traumatically intruded teeth should undergo periodical clinical and radiographic surveillance on a long-term basis to allow early detection of possible complications. PMID:19722445

  20. Extraction of an incisor embedded within the nasal cavity in two guinea pigs

    PubMed Central

    KIDO, Nobuhide; ONO, Kaori; OMIYA, Tomoko; OGUCHI, Yukio; SETOGAWA, Moemi; MACHIDA, Yuuki

    2015-01-01

    Oral examination of two guinea pigs revealed that the unilateral incisor was absent. On radiographic examination, the incisor was identified within the nasal cavity in both patients. Under anesthesia in both patients, the skin was incised from the nostril to 1.5 cm proximal, and the premaxilla and part of the maxilla were exposed. The bone was removed using a surgical drill, and the incisor was exposed in the nasal cavity. The root was grasped with forceps and carefully extracted as it was degraded and very fragile. Diagnosis was easy using oral and radiographic examination. In guinea pig patients where an incisor is absent on oral examination, this condition should be considered. PMID:26118492

  1. Extraction of an incisor embedded within the nasal cavity in two guinea pigs.

    PubMed

    Kido, Nobuhide; Ono, Kaori; Omiya, Tomoko; Oguchi, Yukio; Setogawa, Moemi; Machida, Yuuki

    2016-01-01

    Oral examination of two guinea pigs revealed that the unilateral incisor was absent. On radiographic examination, the incisor was identified within the nasal cavity in both patients. Under anesthesia in both patients, the skin was incised from the nostril to 1.5 cm proximal, and the premaxilla and part of the maxilla were exposed. The bone was removed using a surgical drill, and the incisor was exposed in the nasal cavity. The root was grasped with forceps and carefully extracted as it was degraded and very fragile. Diagnosis was easy using oral and radiographic examination. In guinea pig patients where an incisor is absent on oral examination, this condition should be considered. PMID:26118492

  2. [Treatment of complete traumatic avulsion of an incisor tooth in adults].

    PubMed

    Benmansour, A

    2013-05-01

    It is possible to replant an incisor tooth completely avulsed after trauma in adults. These cases are relatively frequent among athletes. It is essential to conserve the tooth in saline solution. The time before replantation must be as short as possible. The simple technique described here, which requires a minimum of material and no dental chair, makes it possible to replant an avulsed incisor with a good success rate. PMID:23803559

  3. Class II, Division 1 Angle malocclusion with severe proclination of maxillary incisors

    PubMed Central

    Montanha, Kátia

    2016-01-01

    Protrusion of maxillary incisors is a common complaint among patients seeking orthodontic treatment. This report addresses the correction of Class II Angle malocclusion with excessively bucally proclined maxillary incisors, in an adolescent female patient, through the use of extraoral and fixed appliances. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements for obtaining the title of certified by the BBO. PMID:27007768

  4. A role for suppressed incisor cuspal morphogenesis in the evolution of mammalian heterodont dentition

    PubMed Central

    Ohazama, Atsushi; Blackburn, James; Porntaveetus, Thantrira; Ota, Masato S.; Choi, Hong Y.; Johnson, Eric B.; Myers, Philip; Oommen, Shelly; Eto, Kazuhiro; Kessler, John A.; Kondo, Takashi; Fraser, Gareth J.; Streelman, J. Todd; Pardiñas, Ulyses F. J.; Tucker, Abigail S.; Ortiz, Pablo E.; Charles, Cyril; Viriot, Laurent; Herz, Joachim; Sharpe, Paul T.

    2009-01-01

    Changes in tooth shape have played a major role in vertebrate evolution with modification of dentition allowing an organism to adapt to new feeding strategies. The current view is that molar teeth evolved from simple conical teeth, similar to canines, by progressive addition of extra “cones” to form progressively complex multicuspid crowns. Mammalian incisors, however, are neither conical nor multicuspid, and their evolution is unclear. We show that hypomorphic mutation of a cell surface receptor, Lrp4, which modulates multiple signaling pathways, produces incisors with grooved enamel surfaces that exhibit the same molecular characteristics as the tips of molar cusps. Mice with a null mutation of Lrp4 develop extra cusps on molars and have incisors that exhibit clear molar-like cusp and root morphologies. Molecular analysis identifies misregulation of Shh and Bmp signaling in the mutant incisors and suggests an uncoupling of the processes of tooth shape determination and morphogenesis. Incisors thus possess a developmentally suppressed, cuspid crown-like morphogenesis program similar to that in molars that is revealed by loss of Lrp4 activity. Several mammalian species naturally possess multicuspid incisors, suggesting that mammals have the capacity to form multicuspid teeth regardless of location in the oral jaw. Localized loss of enamel may thus have been an intermediary step in the evolution of cusps, both of which use Lrp4-mediated signaling. PMID:20018657

  5. Weighting links based on edge centrality for community detection

    NASA Astrophysics Data System (ADS)

    Sun, Peng Gang

    2014-01-01

    Link weights have the equally important position as links in complex networks, and they are closely associated with each other for the emergence of communities. How to assign link weights to make a clear distinction between internal links of communities and external links connecting communities is of vital importance for community detection. Edge centralities provide a powerful approach for distinguishing internal links from external ones. Here, we first use edge centralities such as betweenness, information centrality and edge clustering coefficient to weight links of networks respectively to transform unweighted networks into weighted ones, and then a weighted function that both considers links and link weights is adopted on the weighted networks for community detection. We evaluate the performance of our approach on random networks as well as real-world networks. Better results are achieved on weighted networks with stronger weights of internal links of communities, and the results on unweighted networks outperform that of weighted networks with weaker weights of internal links of communities. The availability of our findings is also well-supported by the study of Granovetter that the weak links maintain the global integrity of the network while the strong links maintain the communities. Especially in the Karate club network, all the nodes are correctly classified when we weight links by edge betweenness. The results also give us a more comprehensive understanding on the correlation between links and link weights for community detection.

  6. Post-traumatic treatment of maxillary incisors by immediate dentoalveolar restoration with long-term follow-up.

    PubMed

    Rosa, Ariádene Cristina Pértile de Oliveira; Francischone, Carlos Eduardo; Cardoso, Mauricio de Almeida; Alonso, Ana Carolina; Filho, Leopoldino Capelozza; da Rosa, José Carlos Martins

    2015-02-01

    Replacing both missing maxillary anterior teeth is particularly challenging, especially in compromised sockets. This case report describes the management of an 18-year-old female patient, who suffered avulsion of both maxillary central incisors at 7 years of age. This multidisciplinary implant technique, called Immediate Dentoalveolar Restoration (IDR), included extraction of the injured teeth and a single procedure for immediate implant placement and restoration of the compromised sockets after root fracture and periapical lesion development were detected during orthodontic treatment. Successful esthetic and functional outcomes and reestablishment of the alveolar process after bone reconstruction were observed during the 3-year follow-up period. The predictable esthetic outcomes and soft- and hard-tissue stability that can be achieved following IDR are demonstrated. PMID:25822639

  7. Surgical Treatment of an Immature Short-Rooted Traumatized Incisor with an Extensive Apical Lesion Using CEM Cement

    PubMed Central

    Asgary, Saeed; Fazlyab, Mahta

    2015-01-01

    Severe traumatic injuries to immature teeth often cause damage to periodontal ligament as well as dental pulp; pulp necrosis, root resorption and subsequent apical lesion are common consequences. This article reports the surgical management of an infected immature maxillary central incisor associated with a gigantic periradicular lesion and severe root resorption. The tooth had a history of trauma and the patient suffered from purulent sinus tract and tooth mobility. After unsuccessful multi-session disinfection with calcium hydroxide, root end surgery was planned. During flap surgery and lesion enucleation, the root end was cleaned and filled with calcium-enriched mixture (CEM) cement. After one year, the radiographic examination revealed that the lesion was almost completely replaced with newly formed bone. In addition, clinical examination showed favorable outcomes; the tooth was symptom-free and in function. Due to chemical, physical and biological properties of CEM cement, this biomaterial might be considered as the root-end filling material of choice. PMID:25834603

  8. Surgical Treatment of an Immature Short-Rooted Traumatized Incisor with an Extensive Apical Lesion Using CEM Cement.

    PubMed

    Asgary, Saeed; Fazlyab, Mahta

    2015-01-01

    Severe traumatic injuries to immature teeth often cause damage to periodontal ligament as well as dental pulp; pulp necrosis, root resorption and subsequent apical lesion are common consequences. This article reports the surgical management of an infected immature maxillary central incisor associated with a gigantic periradicular lesion and severe root resorption. The tooth had a history of trauma and the patient suffered from purulent sinus tract and tooth mobility. After unsuccessful multi-session disinfection with calcium hydroxide, root end surgery was planned. During flap surgery and lesion enucleation, the root end was cleaned and filled with calcium-enriched mixture (CEM) cement. After one year, the radiographic examination revealed that the lesion was almost completely replaced with newly formed bone. In addition, clinical examination showed favorable outcomes; the tooth was symptom-free and in function. Due to chemical, physical and biological properties of CEM cement, this biomaterial might be considered as the root-end filling material of choice. PMID:25834603

  9. Role of attrition and occlusal contact in the physiology of the rat incisor: X. The part played by the periodontal ligament in the eruptive process.

    PubMed

    Pitaru, S; Michaeli, Y; Zajicek, G; Weinreb, M M

    1976-01-01

    Removal of the proliferating base of the rat incisor did not influence the rate of eruption which responded to changes in impediment to eruption in a fashion similar to that for control teeth. It is the peridontal ligament rather than the proliferating cells that is responsible for tooth eruption. The elements of the peridontal ligament apparently responsible for tooth movement are the mature fibroblasts. PMID:1067296

  10. New prediction equations for the estimation of maxillary mandibular canine and premolar widths from mandibular incisors and mandibular first permanent molar widths: A digital model study

    PubMed Central

    Shahid, Fazal; Khamis, Mohd Fadhli

    2016-01-01

    Objective The primary aim of the study was to generate new prediction equations for the estimation of maxillary and mandibular canine and premolar widths based on mandibular incisors and first permanent molar widths. Methods A total of 2,340 calculations (768 based on the sum of mandibular incisor and first permanent molar widths, and 1,572 based on the maxillary and mandibular canine and premolar widths) were performed, and a digital stereomicroscope was used to derive the the digital models and measurements. Mesiodistal widths of maxillary and mandibular teeth were measured via scanned digital models. Results There was a strong positive correlation between the estimation of maxillary (r = 0.85994, r2 = 0.7395) and mandibular (r = 0.8708, r2 = 0.7582) canine and premolar widths. The intraclass correlation coefficients were statistically significant, and the coefficients were in the strong correlation range, with an average of 0.9. Linear regression analysis was used to establish prediction equations. Prediction equations were developed to estimate maxillary arches based on Y = 15.746 + 0.602 × sum of mandibular incisors and mandibular first permanent molar widths (sum of mandibular incisors [SMI] + molars), Y = 18.224 + 0.540 × (SMI + molars), and Y = 16.186 + 0.586 × (SMI + molars) for both genders, and to estimate mandibular arches the parameters used were Y = 16.391 + 0.564 × (SMI + molars), Y = 14.444 + 0.609 × (SMI + molars), and Y = 19.915 + 0.481 × (SMI + molars). Conclusions These formulas will be helpful for orthodontic diagnosis and clinical treatment planning during the mixed dentition stage. PMID:27226963

  11. An efficient community detection method based on rank centrality

    NASA Astrophysics Data System (ADS)

    Jiang, Yawen; Jia, Caiyan; Yu, Jian

    2013-05-01

    Community detection is a very important problem in social network analysis. Classical clustering approach, K-means, has been shown to be very efficient to detect communities in networks. However, K-means is quite sensitive to the initial centroids or seeds, especially when it is used to detect communities. To solve this problem, in this study, we propose an efficient algorithm K-rank, which selects the top-K nodes with the highest rank centrality as the initial seeds, and updates these seeds by using an iterative technique like K-means. Then we extend K-rank to partition directed, weighted networks, and to detect overlapping communities. The empirical study on synthetic and real networks show that K-rank is robust and better than the state-of-the-art algorithms including K-means, BGLL, LPA, infomap and OSLOM.

  12. Central neurocytoma: Management recommendations based on a 35-year experience

    SciTech Connect

    Leenstra, James L.; Rodriguez, Fausto J.; Frechette, Christina M.; Giannini, Caterina; Stafford, Scott L.; Pollock, Bruce E.; Schild, Steven E.; Scheithauer, Bernd W.; Jenkins, Robert B.; Buckner, Jan C.; Brown, Paul D.

    2007-03-15

    Purpose: To examine the outcomes of patients with histologically confirmed central neurocytomas. Methods and Materials: The data from 45 patients with central neurocytomas diagnosed between 1971 and 2003 were retrospectively evaluated. Various combinations of surgery, radiotherapy (RT), and chemotherapy had been used for treatment. Results: The median follow-up was 10.0 years. The 10-year overall survival and local control rate was 83% and 60%, respectively. Patients whose tumor had a mitotic index of <3 (per 10 high-power fields) experienced a 10-year survival and local control rate of 89% and 74%, respectively, compared with 57% (p = 0.040) and 46% (p = 0.14) for patients with a tumor mitotic index of {>=}3. The 10-year survival and local control rate was 90% and 74% for patients with typical tumors compared with 63% (p = 0.055) and 46% (p = 0.41) for those with atypical tumors. A comparison of gross total resection with subtotal resection showed no significant difference in survival or local control. Postoperative RT improved local control at 10 years (75% with RT vs. 51% without RT, p = 0.045); however, this did not translate into a survival benefit. No 1p19q deletions were found in the 19 tumors tested. Conclusion: Although the overall prognosis is quite favorable, one-third of patients experienced tumor recurrence or progression at 10 years, regardless of the extent of the initial resection. Postoperative RT significantly improved local control but not survival, most likely because of the effectiveness of salvage RT. For incompletely resected atypical tumors and/or those with a high mitotic index, consideration should be given to adjuvant RT because of the more aggressive nature.

  13. Static Thrust of an Annular Nozzle with a Concave Central Base

    NASA Technical Reports Server (NTRS)

    Corson, Blake W., Jr.; Mercer, Charles E.

    1960-01-01

    A static test of an annular nozzle with a concave central base, producing a jet in which tangents to the jet streamlines at the exit converged toward a region on the axis of symmetry downstream of the exit, has indicated good thrust performance. A value of nozzle-flow coefficient only slightly less than unity indicates the internal loss to be small. Pressures on the concave central base are relatively large and positive, and a predictable portion of the total thrust of the jet is exerted on the central base.

  14. [Multi-bed & multi-parameter central monitoring system based on TCP/IP protocol].

    PubMed

    Lian, S J; Hu, D K; Zhao, M H; Tang, L H

    2000-02-01

    Communication is one of the key problems to a central monitoring system. In this paper we put forward a central monitoring system using TCP/IP as the network protocol, Windows NT4.0 as the platform, forming a Intranet in a hospital. We also discussed the communication problem between the bed-side monitoring station and the central monitoring station in detail and then put forward a new protocol--Hospital Central Monitor Protocol (HCMP) based on TCP/IP to transfer monitoring data. It is easy to achieve tele-monitoring through the current communication subsystem. PMID:12583091

  15. An Agent-Based Model of Centralized Institutions, Social Network Technology, and Revolution

    PubMed Central

    Makowsky, Michael D.; Rubin, Jared

    2013-01-01

    This paper sheds light on the general mechanisms underlying large-scale social and institutional change. We employ an agent-based model to test the impact of authority centralization and social network technology on preference falsification and institutional change. We find that preference falsification is increasing with centralization and decreasing with social network range. This leads to greater cascades of preference revelation and thus more institutional change in highly centralized societies and this effect is exacerbated at greater social network ranges. An empirical analysis confirms the connections that we find between institutional centralization, social radius, preference falsification, and institutional change. PMID:24278280

  16. [Local application of simvastatin to rat incisor sockets augments bone].

    PubMed

    Nishimura, Kenichi

    2008-03-01

    Decrease of the alveolar ridge after tooth extraction causes difficulties in prosthodontic treatment, especially in implant supported prostheses. Statins, which are inhibitors of cholesterol synthesis and therapeutic drugs for hypercholestemia, stimulate BMP-2 expression in osteoblasts. The purpose of the present study was to examine how local application of simvastatin, one of the statins, to the tooth socket after tooth extraction affects alveolar bone. A mixture of lactic acid/glycolic acid copolymer (PLGA), alpha-tricalcium phosphate (alpha-TCP), calcium carbonate was prepared as a carrier for simvastatin. Ninety-six male Wistar rats, 10 weeks old, were used. After right mandibular incisor extraction, they were divided into eight groups and tooth sockets were treated differently: no treatment (control), PLGA carrier only, or PLGA containing 0.1, 0.25, 0.5, 1.0, 2.0, and 4.0 mg simvastatin, respectively. They were sacrificed at 4 and 8 weeks. Bone mineral content (BMC) of the alveolar ridge was measured with dual-energy X-ray absorptiometry and histological analyses were performed. All groups treated with simvastatin showed higher BMC compared to the control group and PLGA carrier group at 4 and 8 weeks. Histological analyses revealed that the thickness of cortical bone of the statin group increased compared to the control group at 4 and 8 weeks; however, newly-formed bone in the tooth socket of the statin group was less than in those of the control group and PLGA carrier group. The results of this study show that local application of simvastatin may enhance bone formation and preserve the alveolar ridge after tooth extraction. PMID:18421951

  17. A development-based compartmentalization of the Drosophila central brain

    PubMed Central

    Pereanu, Wayne; Kumar, Abilasha; Jennett, Arnim; Reichert, Heinrich; Hartenstein, Volker

    2010-01-01

    The neuropile of the Drosophila brain is subdivided into anatomically discrete compartments. Compartments are rich in terminal neurite branching and synapses; they are the neuropile domains in which signal processing takes place. Compartment boundaries are defined by more or less dense layers of glial cells, as well as long neurite fascicles. These fascicles are formed during the larval period when the approximately 100 neuronal lineages that constitute the Drosophila central brain differentiate. Each lineage forms an axon tract with a characteristic trajectory in the neuropile; groups of spatially related tracts congregate into the brain fascicles that can be followed from the larva throughout metamorphosis into the adult stage. In this paper we provide a map of the adult brain compartments and the relevant fascicles defining compartmental boundaries. We have identified the neuronal lineages contributing to each fascicle, which allowed us to directly compare compartments of the larval and adult brain. Most adult compartments can be recognized already in the early larval brain where they form a “protomap” of the later adult compartments. Our analysis highlights the morphogenetic changes shaping the Drosophila brain; the data will be important for studies that link early acting genetic mechanisms to the adult neuronal structures and circuits controlled by these mechanisms. PMID:20533357

  18. The Effect of Changes in Lower Incisor Inclination on Gingival Recession

    PubMed Central

    Kamak, Gulen; Kamak, Hasan; Keklik, Hakan; Gurel, Hakan Gurcan

    2015-01-01

    Aim. Orthodontic treatment may promote development of recessions. The mechanism by which orthodontic treatment influences occurrence of recessions remains unclear. The aim of this study was to test the hypothesis that a change of mandibular incisor inclination promotes development of labial gingival recessions. Materials and Methods. The study sample comprised dental casts and lateral cephalograms obtained from 109 subjects before orthodontic treatment (Tb) and after orthodontic treatment (Ta). Depending on the change of lower incisor inclination during treatment, the subjects were divided into three groups: Retroclination (R), Stable Position (S), and Proclination (P). The presence of gingival recessions of mandibular incisors and clinical crown heights were assessed on plaster models. Results and Conclusions. From Tb to Ta, Inc_Incl showed a statistically significant change in the R, P, and S groups (p < 0.05). Increase of clinical crown heights of the lower incisors (42, 4, and 31) was not statistically significant in any group. The only statistically significant intergroup difference was the greater increase of the clinical crown height of tooth number 32 in the P group in comparison with the R group (p = 0.049). The change of lower incisor inclination during treatment did not lead to development of labial gingival recessions in the study sample. PMID:25961071

  19. Inhibition of Notch Signaling During Mouse Incisor Renewal Leads to Enamel Defects.

    PubMed

    Jheon, Andrew H; Prochazkova, Michaela; Meng, Bo; Wen, Timothy; Lim, Young-Jun; Naveau, Adrien; Espinoza, Ruben; Cox, Timothy C; Sone, Eli D; Ganss, Bernhard; Siebel, Christian W; Klein, Ophir D

    2016-01-01

    The continuously growing rodent incisor is an emerging model for the study of renewal of mineralized tissues by adult stem cells. Although the Bmp, Fgf, Shh, and Wnt pathways have been studied in this organ previously, relatively little is known about the role of Notch signaling during incisor renewal. Notch signaling components are expressed in enamel-forming ameloblasts and the underlying stratum intermedium (SI), which suggested distinct roles in incisor renewal and enamel mineralization. Here, we injected adult mice with inhibitory antibodies against several components of the Notch pathway. This blockade led to defects in the interaction between ameloblasts and the SI cells, which ultimately affected enamel formation. Furthermore, Notch signaling inhibition led to the downregulation of desmosome-specific proteins such as PERP and desmoplakin, consistent with the importance of desmosomes in the integrity of ameloblast-SI attachment and enamel formation. Together, our data demonstrate that Notch signaling is critical for proper enamel formation during incisor renewal, in part by regulating desmosome-specific components, and that the mouse incisor provides a model system to dissect Jag-Notch signaling mechanisms in the context of mineralized tissue renewal. © 2015 American Society for Bone and Mineral Research. PMID:26179131

  20. Gastrin-releasing peptide expression and its effect on the calcification of developing mouse incisor.

    PubMed

    Lee, Dong-Joon; Jin, Chengri; Kim, Eun-Jung; Lee, Jong-Min; Jung, Han-Sung

    2015-09-01

    Gastrin-releasing peptide (GRP) is considered to be one of the cancer growth factors. This peptide's receptor (GRPR) is known as a G protein-coupled receptor, regulating intracellular calcium storage and releasing signals. This study is the first to investigate the function of GRP during mouse incisor development. We hypothesized that GRP is one of the factors that affects the regulation of calcification during tooth development. To verify the expression pattern of GRP, in situ hybridization was processed during incisor development. GRP was expressed at the late bell stage and hard tissue formation stage in the epithelial tissue. To identify the genuine function of GRP during incisor development, a gain-of-function analysis was performed. After GRP overexpression in culture, the phenotype of ameloblasts, odontoblasts and predentin was altered compared to control group. Moreover, enamel and dentin thickness was increased after renal capsule transplantation of GRP-overexpressed incisors. With these results, we suggest that GRP plays a significant role in the formation of enamel and dentin by regulating ameloblasts and predentin formation, respectively. Thus, GRP signaling is strongly related to calcium acquisition and secretion during mouse incisor development. PMID:26126650

  1. IN VITRO INCIDENCE OF ROOT CANAL BIFURCATION IN MANDIBULAR INCISORS BY RADIOVISIOGRAPHY

    PubMed Central

    de Oliveira, Simone Helena Gonçalves; de Moraes, Luiz César; Faig-Leite, Horácio; Camargo, Samira Esteves Afonso; Camargo, Carlos Henrique Ribeiro

    2009-01-01

    Objective: The aim of this study was to verify, in vivo and in vitro, the prevalence of root canal bifurcation in mandibular incisors by digital radiography. Material and Methods: Four hundred teeth were analyzed for the in vivo study. Digital radiographs were taken in an orthoradial direction from the mandibular incisor and canine regions. The digital radiographs of the canine region allowed visualizing the incisors in a distoradial direction using 20° deviation. All individuals agreed to participate by signing an informed consent form. The in vitro study was conducted on 200 mandibular incisors positioned on a model, simulating the mandibular dental arch. Digital radiographs were taken from the mandibular incisors in both buccolingual and mesiodistal directions. Results: The digital radiography showed presence of bifurcation in 20% of teeth evaluated in vitro in the mesiodistal direction. In the buccolingual direction, 17.5% of teeth evaluated in vivo and 15% evaluated in vitro presented bifurcation or characteristics indicating bifurcation. Conclusions: Digital radiography associated with X-ray beam distally allowed detection of a larger number of cases of bifurcated root canals or characteristics of bifurcation. PMID:19466258

  2. Transoral robotic surgery of the central skull base: preclinical investigations.

    PubMed

    Fernandez-Nogueras, F J J; Katati, M J; Arraez Sanchez, M A; Molina Martinez, M; Sanchez Carrion, M

    2014-06-01

    In this study we explored possible applications of the da Vinci system in approaching the skull base at optic chiasm level on two cryopreserved cadavers, using an entirely transoral robotic technique (TORS). We used a standard 12 mm endoscopy and 8 mm terminals. Bone drilling was performed manually. The da Vinci system is equipped with very good illumination and 3D viewing, thus providing excellent vision and great maneuverability even in the less accessible areas of the skull. Our experience demonstrates that an entirely transoral skull base robotic approach to this complex anatomical region has many advantages as compared to traditional techniques. PMID:24077869

  3. School-Based Management in Hong Kong: Centralizing or Decentralizing

    ERIC Educational Resources Information Center

    Pang, I-Wah

    2008-01-01

    This paper examined the debate on a reform of school-based management in Hong Kong, which was to set up the Incorporated Management Committee (IMC) to manage the subsidized school. The nature of the debate during legislation and the characteristics of the reform were examined. The advantages, disadvantages and the implications of the reform were…

  4. Orthodontic treatment of a mandibular incisor fenestration resulting from a broken retainer.

    PubMed

    Farret, Marcel M; Farret, Milton M B; da Luz Vieira, Gustavo; Assaf, Jamal Hassan; de Lima, Eduardo Martinelli S

    2015-08-01

    This article describes the orthodontic relapse with mandibular incisor fenestration in a 36-year-old man who had undergone orthodontic treatment 21 years previously. The patient reported that his mandibular 3 × 3 bonded retainer had been partially debonded and broken 4 years earlier. The mandibular left lateral incisor remained bonded to the retainer and received the entire load of the incisors; consequently, there was extreme labial movement of the root, resulting in dental avulsion. As part of the treatment, the root was repositioned lingually using a titanium-molybdenum segmented archwire for 8 months, followed by endodontic treatment, an apicoectomy, and 4 months of alignment and leveling of both arches. The treatment outcomes were excellent, and the tooth remained stable, with good integrity of the mesial, distal, and lingual alveolar bones and periodontal ligament. The 1-year follow-up showed good stability of the results. PMID:26232842

  5. Interdisciplinary treatment of an end-to-end occlusion due to congenitally missing maxillary lateral incisors.

    PubMed

    Sesemann, Michael R; Patrick, Bradford

    2010-01-01

    Odontogenic aplasia, or the congenital absence of permanent teeth, is relatively common. When the missing teeth include the maxillary lateral incisors, treatment considerations must reconcile both esthetic and functional objectives. In developing dentition, erupting adjacent teeth can drift from their intended positions into the edentulous space created by the congenitally missing tooth. When this movement happens (e.g., cuspids shifting more mesially than normal), esthetic and functional problems occur. A restorative solution for missing maxillary lateral incisors subsequent to the loss of the maxillary incisor spaces is presented while highlighting the use of a leucite-reinforced material. This approach allowed for a minimal preparation design and conservation of tooth structure, providing an optimal bond. PMID:20712109

  6. Spectrophotometric color evaluation of permanent incisors, canines and molars. A cross-sectional clinical study

    PubMed Central

    POP-CIUTRILA, IOANA-SOFIA; COLOSI, HORATIU ALEXANDRU; DUDEA, DIANA; BADEA, MANDRA EUGENIA

    2015-01-01

    Background and aims An accurate color reproduction represents the final validation level of an esthetic anterior or posterior restoration. The aim of this study was to evaluate the color of permanent maxillary incisors, canines and molars, using a clinical spectrophotometer. Methods The Vita Easyshade Advance 4.0® intraoral spectrophotometer was used by one clinician to determine the color of 369 permanent maxillary incisors, canines and molars. The best matches to Vitapan Classical® and 3D-Master® shade guides were recorded. A one-way analysis of variance and Kruskal-Wallis test were used to compare L*, a*, b*, c* and h* color coordinates among the 3 types of teeth. Differences between the mean values of all color coordinates were evaluated by use of Bonferroni corrections. Color difference (ΔE*) between incisors, canines and molars was calculated from ΔL*, Δa* and Δb* data and the results were compared to ΔE*=3.3 acceptability threshold. Results Except for Δa* and Δh* between canines and molars, statistically significant differences among the mean differences of all color coordinates were found when the 3 types of teeth were compared by pairs. The most frequently measured shades were A1 (48.4%), respectively 1M1 (31.5%) for incisors, B3 (36.6%), respectively 2M3 (39.8%) for canines and B3 (44.7%), respectively 2M3 (52%) for molars. Incisors had the highest lightness values, followed by canines and molars. Molars were the most chromatic with the highest a* and b* values. Conclusions Despite the limitations of this study, color differences among incisors, canines and molars were found to be statistically significant, above the clinical acceptability threshold established. In conclusion, successful esthetic restorations of permanent teeth of the same patient need an individual color assessment and reproduction of every type of tooth. PMID:26733753

  7. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient

    PubMed Central

    Machado, Gislana Braga

    2015-01-01

    Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as a requirement for the title of certified by the BBO. PMID:26154463

  8. Agenesis of Maxillary Lateral Incisors: Treatment Involves Much More Than Just Canine Guidance

    PubMed Central

    Silveira, Giordani Santos; Mucha, José Nelson

    2016-01-01

    Objective: In this study, we aimed highlight some clinical features present in patients whose maxillary lateral incisors are missing, and proposed more logical, rational and predictable solutions to inform decision making in rehabilitation procedures. Methods: Literature review and discussion. Conclusion: Choosing the best possible treatment for congenital absence of maxillary lateral incisors depends on the multidisciplinary diagnosis of facial, occlusal, functional and periodontal features. It also depends on the individual long-term stability, and it does not only rely on canine-guided disocclusion. PMID:27006720

  9. Orthodontic treatment of unilateral cleft lip and alveolus patient with maxillary lateral incisor missing: case report.

    PubMed

    Pisek, Poonsak; Manosudprasit, Montian; Wangsrimongkol, Tasanee; Pasasuk, Apaporn; Somsuk, Thanatpiya

    2013-09-01

    The esthetics of a patient with a cleft lip and alveolus and missing maxillary lateral incisor is important. A girl, aged 9 years 3 months with repaired left unilateral cleft of primary palate only was referred for orthodontic evaluation of her anterior tooth-crowding. She was unhappy with the unattractive appearance of her maxillary anterior teeth, which were behind her mandibular anterior teeth. Alveolar bone grafting along with canine substitution to replace her missing lateral incisor were recommended for this patient. The post-treatment results were excellent with good occlusion, acceptable profile, and remained stable one year after conclusion of active treatment. PMID:24386758

  10. Perivascular Stem Cells at the Tip of Mouse Incisors Regulate Tissue Regeneration.

    PubMed

    Pang, Yvonne Wy; Feng, Jifan; Daltoe, Felipe; Fatscher, Robert; Gentleman, Eileen; Gentleman, Molly M; Sharpe, Paul T

    2016-03-01

    Cells with in vitro properties similar to those of bone marrow stromal stem cells are present in tooth pulp as quiescent cells that are mobilized by damage. These dental pulp stem cells (DPSCs) respond to damage by stimulating proliferation and differentiation into odontoblast-like cells that form dentine to repair the damage. In continuously growing mouse incisors, tissue at the incisor tips is continuously being damaged by the shearing action between the upper and lower teeth acting to self-sharpen the tips. We investigated mouse incisor tips as a model for the role of DPSCs in a continuous natural repair/regeneration process. We show that the pulp at the incisor tip is composed of a disorganized mass of mineralized tissue produced by odontoblast-like cells. These cells become embedded into the mineralized tissue that is rapidly formed and then lost during feeding. Tetracycline labeling not only revealed the expected incorporation into newly synthesized dentine formation of the incisor but also a zone covering the pulp cavity at the tips of the incisors that is mineralized very rapidly. This tissue was dentine-like but had a significantly lower mineral content than dentine as determined by Raman spectroscopy. The mineral was more crystalline than dentine, indicative of small, defect-free mineral particles. To identify the origin of cells responsible for deposition of this mineralized tissue, we genetically labeled perivascular cells by crossing NG2(ERT2) Cre and Nestin Cre mice with reporter mice. A large number of pericyte-derived cells were visible in the pulp of incisor tips with some having elongated, odontoblast-like shapes. These results show that in mouse incisors, rapid, continuous mineralization occurs at the tip to seal off the pulp tissue from the external environment. The mineral is formed by perivascular-derived cells that differentiate into cells expressing dentin sialo-phosphoprotein (DSPP) and produce a dentine-like material in a process that functions as continuous natural tissue regeneration. © 2015 American Society for Bone and Mineral Research. PMID:26391094

  11. Bilateral Supernumerary Deciduous Maxillary Lateral Incisors with Fusion: Report of a Rare Case

    PubMed Central

    Ghaderi, Faezeh; Rafiee, Azade

    2016-01-01

    Dental anomaly in number, size and shape might be due to excessive activation of dental lamina during the morpho-differentiation stage. Fusion is one of the most unusual and rare anomalies of shape of the teeth. It frequently involves the supernumerary teeth resulting in a challenging differential diagnosis with gemination. Dental anomalies may result in different problems such as delayed eruption and crowding; thus, early diagnosis is required for effective intervention and proper in-time treatment. The case reported here is a 4-year-old girl with bilateral supernumerary primary maxillary lateral incisors associated with fusion between primary maxillary left lateral incisor and supernumerary lateral tooth. PMID:26966712

  12. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient.

    PubMed

    Machado, Gislana Braga

    2015-01-01

    Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as a requirement for the title of certified by the BBO. PMID:26154463

  13. Bilateral Supernumerary Deciduous Maxillary Lateral Incisors with Fusion: Report of a Rare Case.

    PubMed

    Ghaderi, Faezeh; Rafiee, Azade

    2016-03-01

    Dental anomaly in number, size and shape might be due to excessive activation of dental lamina during the morpho-differentiation stage. Fusion is one of the most unusual and rare anomalies of shape of the teeth. It frequently involves the supernumerary teeth resulting in a challenging differential diagnosis with gemination. Dental anomalies may result in different problems such as delayed eruption and crowding; thus, early diagnosis is required for effective intervention and proper in-time treatment. The case reported here is a 4-year-old girl with bilateral supernumerary primary maxillary lateral incisors associated with fusion between primary maxillary left lateral incisor and supernumerary lateral tooth. PMID:26966712

  14. Management of a Previously Treated, Calcified, and Dilacerated Maxillary Lateral Incisor: A Combined Nonsurgical/Surgical Approach Assisted by Cone-beam Computed Tomography.

    PubMed

    Dudeja, Pooja Gupta; Dudeja, Krishan Kumar; Garg, Arvind; Srivastava, Dhirendra; Grover, Shibani

    2016-06-01

    Teeth with calcified canals, dilacerated roots, and associated large periradicular lesions involving both cortical plates pose a challenge to dentists. In addition to the nonsurgical endodontic treatment, such teeth may require surgical intervention with concomitant use of bone grafting materials and barrier techniques. These techniques, when combined with the use of a host modulating agent such as platelet-rich fibrin (PRF), may improve the chances of success. A 26-year-old woman was referred for dental treatment with a recurrence of an intraoral sinus tract 2 months after periradicular surgery in the upper anterior region. Clinical and radiographic examinations revealed a calcified and perforated maxillary left lateral incisor with a severely dilacerated root as well as an associated large radiolucent lesion surrounding the roots of the maxillary left central and lateral incisors. A cone-beam computed tomographic scan of the anterior maxilla showed erosion of the labial and palatal cortical plates in the same region. A calcified canal in the lateral incisor was negotiated up to the straight line portion of the canal. Periradicular surgery with root-end resection was performed, and root-end filling was performed with mineral trioxide aggregate. The perforation present on the middle third of the labial surface of the root was repaired with mineral trioxide aggregate, and the canal was cleaned, shaped, and obturated. A PRF scaffold was prepared and used with a collagen membrane and a freeze-dried bone allograft. Follow-up visits after 3 months, 6 months, and 1 year revealed satisfactory clinical and radiographic healing. The combined use of nonsurgical and surgical modes of treatment cannot be overemphasized in this case. The use of PRF along with a bone graft and a barrier membrane may have enhanced the speed of healing and the resolution of periradicular radiolucency by enhancing bone regeneration. PMID:27140443

  15. Impact resistance of crowned endodontically treated central incisors with internal composite cores.

    PubMed

    Cathro, P R; Chandler, N P; Hood, J A

    1996-06-01

    The impact fracture resistance of crowned endodontically treated teeth with composite cores but without posts, that had either no coronal dentin remaining or a 1 mm dentin collar was compared to that of unrestored caries free teeth. The teeth were struck mid-labially to simulate a common trauma situation using a pendulum device and fracture resistance determined by calculation of absorbed energies. No significant difference was found between the intact teeth and the crowned root treated teeth with composite core and a 1 mm dentin collar. Crowned root treated teeth with a composite core but no coronal dentin had significantly reduced fracture resistance (p < 0.05). Teeth with the dentin collar mainly fractured obliquely from the buccal crown margin to a point coincident with the simulated alveolus, representing a clinical situation which would allow retention rather than extraction of the tooth. PMID:9028189

  16. Caribbean and Central American Women's Feminist Inquiry through Theater-Based Action Research

    ERIC Educational Resources Information Center

    Sánchez Ares, Rocío

    2015-01-01

    Feminist action research interrogates gendered dynamics in the development of a collective consciousness. A group of immigrant Latina women (Latinas) from the Caribbean and Central America employed community-based theater as an instrument to mobilize diverse audiences against discriminatory practices and policies. Based on their theater work, I…

  17. Caribbean and Central American Women's Feminist Inquiry through Theater-Based Action Research

    ERIC Educational Resources Information Center

    Snchez Ares, Roco

    2015-01-01

    Feminist action research interrogates gendered dynamics in the development of a collective consciousness. A group of immigrant Latina women (Latinas) from the Caribbean and Central America employed community-based theater as an instrument to mobilize diverse audiences against discriminatory practices and policies. Based on their theater work, I

  18. Mandibular Symphyseal/Parasymphyseal Fracture with Incisor Tooth Loss: Preventing Lower Arch Constriction.

    PubMed

    Rahpeyma, Amin; Khajehahmadi, Saeedeh; Abdollahpour, Somayeh

    2016-03-01

    Mandibular fractures are the second most common fractures of the face after the nasal bone. Mandibular symphyseal/parasymphyseal fracture comprises 15.6 to 29.3% of mandibular fractures. Tooth loss in the fracture line is a known phenomenon, but space loss has not been evaluated comprehensively in the literature. In a retrospective study, patients with mandibular symphyseal/parasymphyseal fractures, who had been treated from 2012 to 2013 in Mashhad University, Iran, Emdadi Hospital, were recalled. Patients with mandibular incisor tooth/teeth loss were included in the study. Space loss, the technique used to replace the lost tooth/teeth, upper and lower dental midline relationship, combination fracture or fractures in other facial skeleton, and type of treatment were evaluated. Of 98 patients with mandibular symphyseal/parasymphyseal fractures, 22.5% had incisor tooth/teeth loss. In this group, 73% had space loss. Only four patients had replaced the lost tooth/teeth. Dental midlines did not match each other in patients whose feature was evaluated. Open reduction and internal fixation with miniplates were used in symphyseal/parasymphyseal fractures except one. Space loss after mandibular symphyseal/parasymphyseal fracture with incisor tooth loss is a common error. The most important factor to prevent complications related to space loss following mandibular symphyseal/parasymphyseal fracture accompanying incisor tooth loss is space preservation. PMID:26889343

  19. Measurement of Incisor Overjet and Physiological Diastemata Parameters in Quarter Horse Foals.

    PubMed

    Omura, Carla Michel; Drumond, Bianca; Rossi, João Luiz Júnior; Coelho, Clarisse Simões; Gioso, Marco Antônio

    2015-01-01

    Cephalometric studies are important to quantify abnormalities of jaw length and positioning. In this study, 4 to 7-month-old Quarter horse foals (n = 51) were examined to determine overjet (horizontal overlap) prevalence and measure the size of the physiological diastemata. Results were analyzed in relation to age, sex, and lineage. Another aim of this study was to develop a simple field technique for measuring incisor malocclusion and physiological diastemata dimensions that could be used to monitor the growth of the rostral components of maxilla, incisive bone, and mandible. The overall prevalence of overjet lesions in these foals was 51%. Females were overrepresented (61.5%). Overjet occurred more commonly in show foals (50% prevalence) than other working (7.7%) and race (42.3%) lineage foals. Significant differences were found between maxillary and mandibular physiological diastemata lengths in foals of all ages and, as expected, there was a positive statistical correlation between age and maxillary and mandibular physiological diastemata measurements. Incisor overjet was present in 44.4% of 4-month-old foals, 45.5% of 5-month-old foals, 58.3% of 6-month-old foals, and 60% of 7-month-old foals. There was a weak positive correlation between age and the presence of incisor overjet. It was concluded that incisor overiet was common among Quarter horse foals, especially those from show and race lineages. The field technique for physiological diastema measurements was considered effective. PMID:26638296

  20. Prosthetic and orthodontic rehabilitation of a patient with missing maxillary lateral incisors: a case report.

    PubMed

    Gür, Emel; Aykent, Filiz; Gelgör, Ibrahim Erhan

    2007-01-01

    IPS Empress 2 materials can be used for fabrication of short-span fixed partial dentures in the anterior region as well as single crowns. This clinical report describes the prosthodontic treatment of a 16-year-old male patient with missing permanent maxillary left and right incisors with IPS Empress 2 fixed partial dentures following orthodontic treatment. PMID:17508075

  1. Spatial drought reconstructions for central High Asia based on tree rings

    NASA Astrophysics Data System (ADS)

    Fang, Keyan; Davi, Nicole; Gou, Xiaohua; Chen, Fahu; Cook, Edward; Li, Jinbao; D'Arrigo, Rosanne

    2010-11-01

    Spatial reconstructions of drought for central High Asia based on a tree-ring network are presented. Drought patterns for central High Asia are classified into western and eastern modes of variability. Tree-ring based reconstructions of the Palmer drought severity index (PDSI) are presented for both the western central High Asia drought mode (1587-2005), and for the eastern central High Asia mode (1660-2005). Both reconstructions, generated using a principal component regression method, show an increased variability in recent decades. The wettest epoch for both reconstructions occurred from the 1940s to the 1950s. The most extreme reconstructed drought for western central High Asia was from the 1640s to the 1650s, coinciding with the collapse of the Chinese Ming Dynasty. The eastern central High Asia reconstruction has shown a distinct tendency towards drier conditions since the 1980s. Our spatial reconstructions agree well with previous reconstructions that fall within each mode, while there is no significant correlation between the two spatial reconstructions.

  2. Detecting local community structures in complex networks based on local degree central nodes

    NASA Astrophysics Data System (ADS)

    Chen, Qiong; Wu, Ting-Ting; Fang, Ming

    2013-02-01

    Detecting local communities in real-world graphs such as large social networks, web graphs, and biological networks has received a great deal of attention because obtaining complete information from a large network is still difficult and unrealistic nowadays. In this paper, we define the term local degree central node whose degree is greater than or equal to the degree of its neighbor nodes. A new method based on the local degree central node to detect the local community is proposed. In our method, the local community is not discovered from the given starting node, but from the local degree central node that is associated with the given starting node. Experiments show that the local central nodes are key nodes of communities in complex networks and the local communities detected by our method have high accuracy. Our algorithm can discover local communities accurately for more nodes and is an effective method to explore community structures of large networks.

  3. Central venous blood gas and acid-base status in conscious dogs and cats.

    PubMed

    Tamura, Jun; Itami, Takaharu; Ishizuka, Tomohito; Fukui, Sho; Miyoshi, Kenjirou; Sano, Tadashi; Yamashita, Kazuto

    2015-07-01

    To determine the reference level of central venous oxygen saturation (ScvO2) and clinical efficacy of central venous blood gas analysis, partial pressures of oxygen and carbon dioxide, pH, oxygen saturation, base excess (B.E.) and HCO3 concentration were compared between simultaneously obtained central venous and arterial blood samples from conscious healthy 6 dogs and 5 cats. Comparisons between arteriovenous samples were performed by a paired t-test and Bland-Altman analysis. Between arteriovenous samples, B.E. showed good agreement, but there were significant differences in other parameters in the dogs, and no good agreement was detected in cats. The ScvO2 in dogs and cats were 82.3 3.5 and 62.4 13.5%, respectively. Central venous blood gas analysis is indispensable, especially in cats. PMID:25754649

  4. Organic and inorganic content of fluorotic rat incisors measured by FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Porto, Isabel Maria; Saiani, Regina Aparecida; Chan, K. L. Andrew; Kazarian, Sergei G.; Gerlach, Raquel Fernanda; Bachmann, Luciano

    2010-09-01

    Details on how fluoride interferes in enamel mineralization are still controversial. Therefore, this study aimed at analyzing the organic contents of fluorosis-affected teeth using Fourier Transformation Infrared spectroscopy. To this end, 10 male Wistar rats were divided into two groups: one received 45 ppm fluoride in distilled water for 60 days; the other received distilled water only. Then, the lower incisors were removed and prepared for analysis by two FTIR techniques namely, transmission and micro-ATR. For the first technique, the enamel was powdered, whereas in the second case one fluorotic incisor was cut longitudinally for micro-ATR. Using transmission and powdered samples, FTIR showed a higher C-H content in the fluorotic enamel compared with control enamel ( p < 0.05, n = 4 in the flurotic, and n = 5 in the control group). Results from the micro-ATR-FTIR spectroscopic analysis on one longitudinally cut incisor carried out at six points reveal a higher C-H bond content at the surface of the enamel, with values decreasing toward the dentine-enamel junction, and reaching the lowest values at the subsuperficial enamel. These results agree with the morphological data, which indicate that in the rat incisor the fluorotic lesion is superficial, rather than subsuperficial, as in the case of human enamel. The results also suggest that the increased C-H bond content may extend toward the more basal enamel (intraosseous), indicating that fluorotic enamel may intrinsically contain more protein. Finally, particularly when coupled to ATR, FTIR is a suitable tool to study the rat incisor enamel, which is a largely used model of normal and abnormal amelogenesis. Further studies along this line may definitely answer some questions regarding protein content in fluorotic enamel as well as their origin.

  5. Amputation of an Extra-root with an Endodontic Lesion in an Invaginated Vital Maxillary Lateral Incisor: A Rare Case with Seven-year Follow-up

    PubMed Central

    Çalışkan, Mehmet Kemal; Asgary, Saeed; Tekin, Uğur; Güneri, Pelin

    2016-01-01

    The developmental abnormality of tooth resulting from the infolding of enamel/dentin into the root is called dens invaginatus. Management of such cases is usually challenging due to the morphological complexity of root canal system. This report presents a rare treatment protocol of a clinical case of Oehler’s type III dens invaginatus combined with an endodontic lesion in a vital maxillary lateral incisor. Access to the endodontic lesion located between the central and lateral incisors was achieved by reflection of a full mucoperiosteal flap. Granulomatous tissue as well as aberrant root was removed and the surface of the root and adjacent coronal region were reshaped. Three years later, the patient was orthodontically treated. Seven years after completion of surgical/orthodontic management, the tooth remained asymptomatic and functional with normal periodontium/vital pulp. Radiographically, the healing of the lesion was observed. Actually, vitality of the invaginated tooth and communication between the invagination and the root canal were the most important factors in determining such minimally invasive treatment protocol. Depending on the anatomy of the root canal system, surgical amputation of an invaginated root can be performed to achieve a successful outcome in Oehler’s type III dens invaginatus cases, even though it is associated with apical periodontitis. PMID:27141224

  6. Standardised studies on Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM): a need.

    PubMed

    Elfrink, M E C; Ghanim, A; Manton, D J; Weerheijm, K L

    2015-06-01

    In November 2014, a review of literature concerning prevalence data of Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM) was performed. A search of PubMed online databases was conducted for relevant articles published until November 2014. The reference lists of all retrieved articles were hand-searched. Studies were included after assessing the eligibility of the full-text article. Out of 1078 manuscripts, a total of 157 English written publications were selected based on title and abstract. Of these 157, 60 were included in the study and allocated as 52 MIH and 5 HSPM, and 3 for both MIH and HSPM. These studies utilised the European Academy of Paediatric Dentistry judgment criteria, the modified index of developmental defects of enamel (mDDE) and self-devised criteria, and demonstrated a wide variation in the reported prevalence (MIH 2.9-44 %; HSPM 0-21.8 %). Most values mentioned were representative for specific areas. More studies were performed in cities compared with rural areas. A great variation was found in calibration methods, number of participants, number of examiners and research protocols between the studies. The majority of the prevalence studies also investigated possible aetiological factors. To compare MIH and HSPM prevalence and or aetiological data around the world, standardisation of such studies seems essential. Standardisation of the research protocol should include a clearly described sample of children (minimum number of 300 for prevalence and 1000 for aetiology studies) and use of the same calibration sets and methods whereas aetiological studies need to be prospective in nature. A standardised protocol for future MIH and HSPM prevalence and aetiology studies is recommended. PMID:25894247

  7. CentiServer: A Comprehensive Resource, Web-Based Application and R Package for Centrality Analysis

    PubMed Central

    Jalili, Mahdi; Salehzadeh-Yazdi, Ali; Asgari, Yazdan; Arab, Seyed Shahriar; Yaghmaie, Marjan; Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran

    2015-01-01

    Various disciplines are trying to solve one of the most noteworthy queries and broadly used concepts in biology, essentiality. Centrality is a primary index and a promising method for identifying essential nodes, particularly in biological networks. The newly created CentiServer is a comprehensive online resource that provides over 110 definitions of different centrality indices, their computational methods, and algorithms in the form of an encyclopedia. In addition, CentiServer allows users to calculate 55 centralities with the help of an interactive web-based application tool and provides a numerical result as a comma separated value (csv) file format or a mapped graphical format as a graph modeling language (GML) file. The standalone version of this application has been developed in the form of an R package. The web-based application (CentiServer) and R package (centiserve) are freely available at http://www.centiserver.org/ PMID:26571275

  8. Bacterial penetration of the root canal of intact incisor teeth after a simulated traumatic injury.

    PubMed

    Love, R M

    1996-12-01

    One of the aims in treating traumatised teeth is to maintain the vitality of the pulp or allow conditions favourable for pulp revascularisation. However, infection of the pulp and root canal system may prevent this. A number of pathways have been proposed that allow bacteria to invade the root canal system, however most of these pathways cannot account for pulp infection in teeth that did not sustain injury to the periodontal attachment. Enamel/dentine cracks have been proposed as a portal for bacterial invasion of seemingly intact teeth and the aim of this study was to determine if bacteria could invade the root canal system after a simulated traumatic episode. Twenty intact and sound upper central incisors were chosen and prepared. One tooth was selected as a sterility control and the external crown surface of the remaining 19 teeth was subjected to infection with Streptococcus gordonii in a bacterial microleakage model. Over 7 days samples of growth media from the root canal system were taken and tested for bacteria. Sixteen of the teeth did not demonstrate bacterial invasion over the time frame. These teeth were then prepared for testing in a pendulum impact device and were subjected to a blow which did not fracture the crowns or dislodge the tooth from its simulated alveolus. The teeth were then prepared and tested in the bacterial microleakage model. After impact seven of the teeth demonstrated bacterial invasion of the root canal system (P = 0.002). These teeth were then reprepared for testing in the bacterial microleakage model. The crowns of five teeth, selected at random, were coated with two layers of light cured unfilled resin, the remaining two were used as positive controls. All the teeth coated with resin did not demonstrate bacterial invasion (P = 0.00), while the positive controls demonstrated invasion. The results suggested that enamel/dentine infractions were pathways for bacterial invasion of the root canal system of traumatised teeth. The application of unfilled resin to the anatomical crown prevented infection. PMID:9206377

  9. Cultivating Urban Naturalists: Teaching Experiential, Place-Based Learning through Nature Journaling in Central Park

    ERIC Educational Resources Information Center

    Warkentin, Traci

    2011-01-01

    Preservice educators engaged in experiential, place-based learning through a semester-long assignment in which they observed a specific place in Central Park in Manhattan, New York, and kept a nature journal. The assignment was organized around two pivotal elements: direct, sensory experience and time in place. Both elements added vital dimensions

  10. Cultivating Urban Naturalists: Teaching Experiential, Place-Based Learning through Nature Journaling in Central Park

    ERIC Educational Resources Information Center

    Warkentin, Traci

    2011-01-01

    Preservice educators engaged in experiential, place-based learning through a semester-long assignment in which they observed a specific place in Central Park in Manhattan, New York, and kept a nature journal. The assignment was organized around two pivotal elements: direct, sensory experience and time in place. Both elements added vital dimensions…

  11. Delimitating central areas of cities based on road density: a case study of Guangzhou City

    NASA Astrophysics Data System (ADS)

    Zhang, Qingnian; Lu, Xueqiu

    2009-10-01

    The central area of a city is an important functional unit in many urban studies. It is a region where business concentrates and municipal facilities densely distribute. Traditionally, statistics of economic and social phenomena can be used to delimitate their boundaries. However, traditional methods based on economic and social investigation are labor-intensive and sometimes inaccurate. Alternatively, road networks acting as a kind of infrastructure reflect the association of locations. Thus the concentration of road networks indicates the congestion of social-economic activities and municipal facilities to some extent. Based on density analysis of road networks, the area where roads densely distribute is recognized as the central area of a city. Taking Guangzhou City as an example, the road network was studied on a set of spatial scopes, and the central area was delimitated and analyzed. Results showed that the road-density-based delimitation had to be adjusted according to the road system, and the delimitated area was consistent to the real central area to some extent. Since road data is much accessible, road-based method is useful and practical when short of socialeconomic data.

  12. Zinc iodide-osmium tetroxide impregnation of the "tubulo-vesicular system" in Tomes' process of the rat incisor ameloblast.

    PubMed

    Uchida, T; Warshawsky, H

    1992-03-01

    Zinc iodide-osmium tetroxide (ZIO) is a nonspecific but selective impregnation method that visualizes a tubulo-vesicular system in cells. The detailed structure and three-dimensional distribution of this ZIO-impregnated system was studied in the Tomes' process of secretory ameloblasts in the rat incisor. The ZIO-impregnated system consisted of an extensive array of smooth membrane-bound thick and thin tubules and vesicles. The interconnected thick and thin tubules formed a complex "core network" in the central cytoplasm of Tomes' process that enmeshed and often surrounded individual secretory granules. From the core network, radial branches extended toward the smooth cell membrane of the interdigitating portion of Tomes' process. Although the core network and branches frequently appeared connected to the secretory granules and the cell membrane, stereo-pair electron microscopy failed to show conclusive evidence of such continuity. However, many coated vesiclelike structures were attached to the core network and its branches. No special relationship was found between interrod and rod secretory sites and the tubulo-vesicular network. In thick sections, the ZIO-impregnated tubulo-vesicular network occupied a considerable volume of cytoplasm. The vinblastine-labile nature of this network as demonstrated previously (Nanci et al., 1987) indicated that the system undergoes rapid and extensive turnover. Considering the dynamic nature and sheer volume of the tubulo-vesicular system, we propose that it be regarded as a major cell organelle. PMID:1371907

  13. Evaluation of the Effect of Different Ferrule Designs on Fracture Resistance of Maxillary Incisors Restored with Bonded Posts and Cores

    PubMed Central

    Mahdavi Izadi, Z.; Jalalian, E.; Eyvaz Ziaee, A.; Zamani, L.; Javanshir, B.

    2010-01-01

    Introduction: In cases of severe hard tissue loss, 2 mm circumferential ferrule is difficult to achieve. So in these cases we should use different ferrule designs. This in vitro study investigated the effect of different ferrule designs on the fracture resistance of teeth restored with bonded post and cores. Materials and Methods: Forty freshly-extracted central incisors were endodontically treated. The teeth were randomly divided into four groups; group 1 were teeth with 2 mm circumferential ferrule above the CEJ, group 2 were teeth with 2 mm ferrule only on the palatal side of the teeth, group 3 consisted of teeth with 2 mm ferrule only on the facial side and group 4 were teeth with 2 mm ferrule on the palatal and facial side of teeth with interproximal concavities. All teeth were restored with fiber posts and composite cores. The specimen was mounted on a universal testing machine and compressive load was applied to the long axis of the specimen until failure occurred. Results: The fracture resistance was 533.79 ± 232.28 in group 1, 634.75± 133.35 in group 2, 828.90 ±118.27 in group 3 and 678.78± 160.20 in group 4. The post hoc analysis showed statistically significant difference between groups 1 and 3. Conclusions: The results of this in vitro study showed that facial ferrule increases the fracture resistance of endodontically treated teeth restored with bonded post and cores. PMID:21998789

  14. Eigencentrality based on dissimilarity measures reveals central nodes in complex networks.

    PubMed

    Alvarez-Socorro, A J; Herrera-Almarza, G C; González-Díaz, L A

    2015-01-01

    One of the most important problems in complex network's theory is the location of the entities that are essential or have a main role within the network. For this purpose, the use of dissimilarity measures (specific to theory of classification and data mining) to enrich the centrality measures in complex networks is proposed. The centrality method used is the eigencentrality which is based on the heuristic that the centrality of a node depends on how central are the nodes in the immediate neighbourhood (like rich get richer phenomenon). This can be described by an eigenvalues problem, however the information of the neighbourhood and the connections between neighbours is not taken in account, neglecting their relevance when is one evaluates the centrality/importance/influence of a node. The contribution calculated by the dissimilarity measure is parameter independent, making the proposed method is also parameter independent. Finally, we perform a comparative study of our method versus other methods reported in the literature, obtaining more accurate and less expensive computational results in most cases. PMID:26603652

  15. Eigencentrality based on dissimilarity measures reveals central nodes in complex networks

    NASA Astrophysics Data System (ADS)

    Alvarez-Socorro, A. J.; Herrera-Almarza, G. C.; González-Díaz, L. A.

    2015-11-01

    One of the most important problems in complex network’s theory is the location of the entities that are essential or have a main role within the network. For this purpose, the use of dissimilarity measures (specific to theory of classification and data mining) to enrich the centrality measures in complex networks is proposed. The centrality method used is the eigencentrality which is based on the heuristic that the centrality of a node depends on how central are the nodes in the immediate neighbourhood (like rich get richer phenomenon). This can be described by an eigenvalues problem, however the information of the neighbourhood and the connections between neighbours is not taken in account, neglecting their relevance when is one evaluates the centrality/importance/influence of a node. The contribution calculated by the dissimilarity measure is parameter independent, making the proposed method is also parameter independent. Finally, we perform a comparative study of our method versus other methods reported in the literature, obtaining more accurate and less expensive computational results in most cases.

  16. Eigencentrality based on dissimilarity measures reveals central nodes in complex networks

    PubMed Central

    Alvarez-Socorro, A. J.; Herrera-Almarza, G. C.; González-Díaz, L. A.

    2015-01-01

    One of the most important problems in complex network’s theory is the location of the entities that are essential or have a main role within the network. For this purpose, the use of dissimilarity measures (specific to theory of classification and data mining) to enrich the centrality measures in complex networks is proposed. The centrality method used is the eigencentrality which is based on the heuristic that the centrality of a node depends on how central are the nodes in the immediate neighbourhood (like rich get richer phenomenon). This can be described by an eigenvalues problem, however the information of the neighbourhood and the connections between neighbours is not taken in account, neglecting their relevance when is one evaluates the centrality/importance/influence of a node. The contribution calculated by the dissimilarity measure is parameter independent, making the proposed method is also parameter independent. Finally, we perform a comparative study of our method versus other methods reported in the literature, obtaining more accurate and less expensive computational results in most cases. PMID:26603652

  17. An investigation into the measurement of the working length of immature incisor teeth requiring endodontic treatment in children.

    PubMed

    Baggett, F J; Mackie, I C; Worthington, H V

    1996-08-10

    A study was undertaken to determine if a tactile technique, using absorbent paper points, could be used to estimate the working length of nonvital immature incisor teeth undergoing endodontic treatment. Two operators were involved in measuring 35 incisor teeth. The tactile technique was found to be valid and reliable. In 95% of the cases the estimated working length was within 1 mm of the radiographic diagnostic length. It is recommended that diagnostic radiographs are no longer necessary in the majority of cases involving endodontic treatment of incisor teeth requiring root end closure in children, for practitioners who are regularly carrying out endodontic treatment of immature incisor teeth. However, if a tooth has been on open drainage a diagnostic radiograph is still required. PMID:8810108

  18. Essentiality of Early Diagnosis of Molar Incisor Hypomineralization in Children and Review of its Clinical Presentation, Etiology and Management

    PubMed Central

    Jain, Abhay Kumar; Saha, Sonali; Singh, Jaspal

    2012-01-01

    Abstract Molar incisor hypomineralization (MIH) is a common developmental condition resulting in enamel defects in first permanent molars and permanent incisors. It presents at eruption of these teeth. One to four molars, and often also the incisors, could be affected. Since first recognized, the condition has been puzzling and interpreted as a distinct phenomenon unlike other enamel disturbances. Early diagnosis is essential since, rapid breakdown of tooth structure may occur, giving rise to acute symptoms and complicated treatment. The purpose of this article is to review MIH and illustrate its diagnosis and clinical management in young children. How to cite this article: Garg N, Jain AK, Saha S, Singh J. Essentiality of Early Diagnosis of Molar Incisor Hypomineralization in Children and Review of its Clinical Presentation, Etiology and Management. Int J Clin Pediatr Dent 2012;5(3):190-196. PMID:25206166

  19. Alveolar bone loss around incisors in Class I bidentoalveolar protrusion patients: a retrospective three-dimensional cone beam CT study

    PubMed Central

    Nahm, K-Y; Kang, J-H; Moon, S-C; Choi, Y-S; Kook, Y-A; Kim, S-H; Huang, JC

    2012-01-01

    Objectives The aim of this study was to test the null hypothesis that there is no difference in the alveolar bone thickness, bone loss or incidence of fenestrations between upper and lower incisors in skeletal Class I bidentoalveolar protrusive patients before orthodontic treatment. Methods Three-dimensional (3D) cone beam CT (CBCT) images were taken of 24 patients from the Republic of Korea (17 females and 7 males). Reformatted CBCT images were used to measure labial and lingual alveolar bone thickness (ABT) of the 4 upper incisors and 4 lower incisors of the 24 patients (total n = 192 incisors) at every 1/10 of root length (Level 0, cementoenamel junction (CEJ) area; Level 10, root apex area) as well as alveolar bone area (ABA) and alveolar bone loss (%BL) rate to dental root length. The numbers of fenestration teeth were also tallied. Results All anterior teeth were supported by <1 mm of ABT on the labial surfaces up to root length Level 8. ABA was statistically greater on the lingual aspect than the labial aspect in lower incisors. The %BL was 26.98% in the lower labial region, 19.27% in upper labial aspect and most severe on the lower lingual plate 31.25% compared with the labial plate. There were no significant differences in %BL between subgroups when categorized by sex or age. Fenestrations were 1.37 times more frequent on lower incisors (37) than upper incisors (27). Conclusion The null hypothesis was rejected, confirming that incisor periodontal support is poor and alveolar bone loss is severe even prior to the start of orthodontic treatment. Careful diagnosis using 3D CBCT images is needed to avoid iatrogenic degeneration of periodontal support around anterior teeth, particularly in the lower lingual bone plate region. PMID:22184474

  20. Planar cell polarity protein localization in the secretory ameloblasts of rat incisors.

    PubMed

    Nishikawa, Sumio; Kawamoto, Tadafumi

    2012-05-01

    The localization of the planar cell polarity proteins Vang12, frizzled-3, Vang11, and Celsr1 in the rat incisors was examined using immunocytochemistry. The results showed that Vang12 was localized at two regions of the Tomes' processes of inner enamel-secretory ameloblasts in rat incisors: a proximal and a distal region. In contrast, frizzled-3 was localized at adherens junctions of the proximal and distal areas of inner enamel- and outer enamel-secretory ameloblasts, where N-cadherin and β-catenin were localized. frizzled-3 was also localized in differentiating inner enamel epithelial cells. Vang11 was localized sparsely in differentiating preameloblasts and extensively at the cell boundary of stratum intermedium. Celsr1 was not localized in ameloblasts but localized in odontoblasts extensively. These results suggest the involvement of planar cell polarity proteins in odontogenesis. PMID:22378702

  1. Ageing horses by an examination of their incisor teeth: an (im)possible task?

    PubMed

    Muylle, S; Simoens, P; Lauwers, H

    1996-03-30

    It is generally considered that the age of a horse can be determined by examining its incisor teeth. However, the criteria used to determine age from dental configurations differ widely. The existence of this variety of rules and guidelines was the challenge for the present examination. Detailed descriptions of the incisor teeth of 212 horses of registered age were recorded and the results were compared with the age criteria of various authors. The time at which teeth were shed and the appearance of dental stars seemed to be more reliable features than the disappearance of the cups. The disappearance of the marks occurred four years later than usually stated. Other criteria, such as the presence of the seven-year notch and Galvayne's groove, were too variable and inconsistent to be reliable for the determination of age. PMID:8730689

  2. Unilateral Fusion of Maxillary Lateral Incisor: Diagnosis Using Cone Beam Computed Tomography

    PubMed Central

    Castro, Iury Oliveira; Estrela, Carlos; Souza, Vincius Rezende; Lopes, Lawrence Gonzaga; de Souza, Joo Batista

    2014-01-01

    Objective. The objective of this paper is to report a dental fusion case focusing on clinical and radiographic features for the diagnosis. Method. To report a case of right maxillary lateral incisor fusion and a supernumerary tooth, the anatomy of the root canal and dental united portion were assessed by cone beam computed tomography (CBCT). Results. The clinical examination showed dental juxtaposition with the absence of interdental papilla and esthetic impairment in the right maxillary lateral incisor region. The periapical radiography did not provide enough information for the differential diagnosis due to the inherent limitations of this technique. CBCT confirmed the presence of tooth fusion. Conclusion. CBCT examination supports the diagnosis and provides both the identification of changes in tooth development and the visualization of their extent and limits. PMID:25587463

  3. Anti-triangle centrality-based community detection in complex networks.

    PubMed

    Jia, Songwei; Gao, Lin; Gao, Yong; Wang, Haiyang

    2014-06-01

    Community detection has been extensively studied in the past decades largely because of the fact that community exists in various networks such as technological, social and biological networks. Most of the available algorithms, however, only focus on the properties of the vertices, ignoring the roles of the edges. To explore the roles of the edges in the networks for community discovery, the authors introduce the novel edge centrality based on its antitriangle property. To investigate how the edge centrality characterises the community structure, they develop an approach based on the edge antitriangle centrality with the isolated vertex handling strategy (EACH) for community detection. EACH first calculates the edge antitriangle centrality scores for all the edges of a given network and removes the edge with the highest score per iteration until the scores of the remaining edges are all zero. Furthermore, EACH is characterised by being free of the parameters and independent of any additional measures to determine the community structure. To demonstrate the effectiveness of EACH, they compare it with the state-of-the art algorithms on both the synthetic networks and the real world networks. The experimental results show that EACH is more accurate and has lower complexity in terms of community discovery and especially it can gain quite inherent and consistent communities with a maximal diameter of four jumps. PMID:25014378

  4. CenLP: A centrality-based label propagation algorithm for community detection in networks

    NASA Astrophysics Data System (ADS)

    Sun, Heli; Liu, Jiao; Huang, Jianbin; Wang, Guangtao; Yang, Zhou; Song, Qinbao; Jia, Xiaolin

    2015-10-01

    Community detection is an important work for discovering the structure and features of complex networks. Many existing methods are sensitive to critical user-dependent parameters or time-consuming in practice. In this paper, we propose a novel label propagation algorithm, called CenLP (Centrality-based Label Propagation). The algorithm introduces a new function to measure the centrality of nodes quantitatively without any user interaction by calculating the local density and the similarity with higher density neighbors for each node. Based on the centrality of nodes, we present a new label propagation algorithm with specific update order and node preference to uncover communities in large-scale networks automatically without imposing any prior restriction. Experiments on both real-world and synthetic networks manifest our algorithm retains the simplicity, effectiveness, and scalability of the original label propagation algorithm and becomes more robust and accurate. Extensive experiments demonstrate the superior performance of our algorithm over the baseline methods. Moreover, our detailed experimental evaluation on real-world networks indicates that our algorithm can effectively measure the centrality of nodes in social networks.

  5. Management of geminated maxillary lateral incisor using cone beam computed tomography as a diagnostic tool

    PubMed Central

    James, Elizabeth Prabha; Johns, Dexton Antony; Johnson, KI; Maroli, Ramesh Kumar

    2014-01-01

    Geminated teeth are consequences of developmental anomalies leading to joined elements, due to incomplete attempt of one tooth germ to divide into two. This case report describes successful endodontic treatment of an unaesthetic geminated permanent maxillary lateral incisor tooth and its esthetic rehabilitation using all ceramic crowns. Newer imaging technique like cone beam computed tomography was taken for the better understanding of the complicated root canal morphology. PMID:24944458

  6. Presurgical orthodontic decompensation alters alveolar bone condition around mandibular incisors in adults with skeletal Class III malocclusion

    PubMed Central

    Sun, Boyang; Tang, Jun; Xiao, Ping; Ding, Ying

    2015-01-01

    This study is to use cone beam computed tomography (CBCT) to acquire accurate radiographic images for alveolar bone in lower incisors and the change after presurgical orthodontic treatment. Seventeen patients with skeletal Class III malocclusion, ten normal occlusion subjects, and fifteen patients treated with orthodontic treatment and orthognathic surgery were included. CBCT images were obtained. The labial and lingual inclinations of mandibular incisors, the thickness of alveolar bone, the vertical alveolar height and root length were measured. Alveolar bone thickness at the apex in patients with skeletal Class III malocclusion was thinner than normal subjects. The vertical alveolar bone heights at labial and lingual sides in patients with skeletal Class III malocclusion were both reduced compared with normal subjects, especially at the labial side. There were statistically significant correlations between lower incisor inclination and alveolar bone morphology. After orthodontics, the incisors root apex was closer to the lingual side of alveolar bone. The alveolar bone thickness at apex was not statistically changed. The vertical alveolar bone heights at the labial and lingual sides were both significantly reduced especially the lingual side after presurgical orthodontic treatment. The root length was not significantly changed. In conclusion, the alveolar bone thickness at apex is thinner and the vertical alveolar height is reduced at the labial side. Forward movement of lower incisors during presurgical orthodontic treatment can render the lower incisors root apex closer to the lingual side and the vertical alveolar height is reduced. PMID:26550202

  7. On the cutting edge of organ renewal: identification, regulation and evolution of incisor stem cells

    PubMed Central

    Hu, Jimmy Kuang-Hsien; Mushegyan, Vagan; Klein, Ophir D.

    2014-01-01

    The rodent incisor is one of a number of organs that grow continuously throughout the life of an animal. Continuous growth of the incisor arose as an evolutionary adaptation to compensate for abrasion at the distal end of the tooth. The sustained turnover of cells that deposit the mineralized dental tissues is made possible by epithelial and mesenchymal stem cells residing at the proximal end of the incisor. A complex network of signaling pathways and transcription factors regulates the formation, maintenance, and differentiation of these stem cells during development and throughout adulthood. Research over the past 15 years has led to significant progress in our understanding of this network, which includes FGF, BMP, Notch, and Hh signaling, as well as cell adhesion molecules and microRNAs. This review surveys key historical experiments that laid the foundation of the field and discusses more recent findings that definitively identified the stem cell population, elucidated the regulatory network, and demonstrated possible genetic mechanisms for the evolution of continuously growing teeth. PMID:24307456

  8. A Digital Stereomicroscopic Study of the Radicular Wall Thickness of Two-Canal Mandibular Incisors

    PubMed Central

    Khedmat, Sedigheh; Mohamadian, Sohayla; Kharrazifard, Mohamad Javad

    2015-01-01

    Objectives: This study aimed to assess the radicular wall thickness in mandibular incisors with two canals and find the maximum and minimum thickness to prevent root canal treatment (RCT) procedural errors. Materials and Methods: A total of 160 extracted mandibular incisors were selected and radiographed; out of which, 55 had two canals. Three parallel transverse sections were made in each tooth at 1mm below the cementoenamel junction (CEJ), mid-root and 1 millimeter to the apex. Specimens were evaluated under a stereomicroscope and the thickness of radicular walls in each section was determined for the buccal, lingual and proximal surfaces. Data were statistically analyzed using Pearson’s correlation coefficient test. Results: The thickness of radicular wall decreased from the cervical towards the apex. In all three sections (cervical, mid-root and apical), the thickness of lingual wall was significantly greater than the buccal wall. Also, the thickness of buccal and lingual walls was significantly higher than that of the proximal walls. Conclusion: The lingual radicular wall had the highest thickness in two-canal mandibular incisors. Therefore, in these teeth, the lingual canal is a better choice for post placement. PMID:26877738

  9. The Multidisciplinary Management of Fused Maxillary Lateral Incisor with a Supernumerary Tooth in Cleft Lip Adolescence

    PubMed Central

    Yagci, Ahmet; Cantekin, Kenan; Buyuk, Suleyman Kutalmis; Pala, Kansad

    2014-01-01

    Fusion, an uncommon anomaly of the hard dental tissues, is potentially the cause of clinical problems related to esthetics, tooth spacing, and other periodontal complications. This paper describes a multidisciplinary approach involving surgical, endodontic, restorative, and orthodontic attention for the successful, functional, and esthetic rehabilitation of a maxillary left lateral incisor fused with a supernumerary tooth in unilateral cleft lip adolescence in contralateral side. After clinical and radiographic examinations, a fusion between the left maxillary lateral incisor and a supernumerary tooth was diagnosed in the patient, and a small connection was detected between the pulp systems of the two root canals. The case reported in this paper presents the successful resolution of a fused maxillary lateral incisor with a supernumerary tooth, using endodontic, surgical, restorative, and orthodontic management. The decision made in extracting or retaining the fused tooth depends on the arch discrepancy and esthetic needs. Future studies, with long-term followup, will be helpful in evaluating the long-term efficacy of the different treatment options. PMID:24516763

  10. Differences in the pattern of lanthanum diffusion into predentine and dentine in mouse incisors and molars.

    PubMed

    Torres-Quintana, M A; Septier, D; Goldberg, M

    1999-04-01

    Lanthanum nitrate was either perfused intravascularly or segments of mouse tooth were immersed in a fixative solution containing the tracer. The tracer deposits were examined in young (8-day-old) and older (8-week-old) mouse incisors and molars, demineralized or undemineralized. Lanthanum passed the distal junctional complex of odontoblasts and appeared in the predentine of incisors as large electron-dense stellate aggregates, 40-70 nm in diameter, and in molars as round, 20-40 nm dots. In dentine, tracer deposits were detected at three locations. Near the predentine dentine junction, the tracer densely stained a band 0.5-2.5 microm in width, also termed metadentine; in the inner circumpulpal dentine, the staining was weaker or lacking in an area extending 5-7 microm from the predentine-dentine junction; in outer circumpulpal dentine, lateral diffusion had occurred in porosities of intertubular dentine. Lanthanum impregnated the walls of dentine tubules and a peritubular-like dentine. In contrast, the mantle dentine was never stained. These differences in the pattern of diffusion prove that lanthanum staining is age-dependent and varies between mouse incisors and molars, independently of tissue processing. Architectural properties and driving flux are involved in the transport and localization of lanthanum in predentine and dentine. PMID:10348362

  11. Simple method of designing centralized PI controllers for multivariable systems based on SSGM.

    PubMed

    Dhanya Ram, V; Chidambaram, M

    2015-05-01

    A method is given to design multivariable PI/PID controllers for stable and unstable multivariable systems. The method needs only the steady state gain matrix (SSGM). The method is based on the static decoupler design followed by SISO PI/PID controllers design and combining the resulted decoupler and the diagonal PI(D) controllers as the centralized controllers. The result of the present method is shown to be equivalent to the empirical method proposed by Davison EJ. Multivariable tuning regulators: the feed-forward and robust control of general servo-mechanism problem. IEEE Trans Autom Control 1976;21:35-41. Three simulation examples are given. The performance of the controllers is compared with that of the reported centralized controller based on the multivariable transfer function matrix. PMID:25530257

  12. Scedosporium apiospermum as a rare cause of central skull base osteomyelitis.

    PubMed

    Jalava-Karvinen, Päivi; Nyman, Mikko; Gardberg, Maria; Harju, Inka; Hohenthal, Ulla; Oksi, Jarmo

    2016-03-01

    We report a case of Scedosporium apiospermum mold causing ear infection, central skull base osteomyelitis and finally, occlusion of carotid artery in a 48-year-old diabetic man. The exact diagnosis was established and the severity of the disease understood several months after the onset of symptoms. Despite of appropriate antifungal therapy, and repeated surgical and otological procedures, the infection progressed to fatal cerebral infarction. PMID:27134821

  13. Scedosporium apiospermum as a rare cause of central skull base osteomyelitis

    PubMed Central

    Jalava-Karvinen, Päivi; Nyman, Mikko; Gardberg, Maria; Harju, Inka; Hohenthal, Ulla; Oksi, Jarmo

    2016-01-01

    We report a case of Scedosporium apiospermum mold causing ear infection, central skull base osteomyelitis and finally, occlusion of carotid artery in a 48-year-old diabetic man. The exact diagnosis was established and the severity of the disease understood several months after the onset of symptoms. Despite of appropriate antifungal therapy, and repeated surgical and otological procedures, the infection progressed to fatal cerebral infarction. PMID:27134821

  14. Development of a Physiologically-Based Pharmacokinetic Model of the Rat Central Nervous System

    PubMed Central

    Badhan, Raj K. Singh; Chenel, Marylore; Penny, Jeffrey I.

    2014-01-01

    Central nervous system (CNS) drug disposition is dictated by a drug’s physicochemical properties and its ability to permeate physiological barriers. The blood–brain barrier (BBB), blood-cerebrospinal fluid barrier and centrally located drug transporter proteins influence drug disposition within the central nervous system. Attainment of adequate brain-to-plasma and cerebrospinal fluid-to-plasma partitioning is important in determining the efficacy of centrally acting therapeutics. We have developed a physiologically-based pharmacokinetic model of the rat CNS which incorporates brain interstitial fluid (ISF), choroidal epithelial and total cerebrospinal fluid (CSF) compartments and accurately predicts CNS pharmacokinetics. The model yielded reasonable predictions of unbound brain-to-plasma partition ratio (Kpuu,brain) and CSF:plasma ratio (CSF:Plasmau) using a series of in vitro permeability and unbound fraction parameters. When using in vitro permeability data obtained from L-mdr1a cells to estimate rat in vivo permeability, the model successfully predicted, to within 4-fold, Kpuu,brain and CSF:Plasmau for 81.5% of compounds simulated. The model presented allows for simultaneous simulation and analysis of both brain biophase and CSF to accurately predict CNS pharmacokinetics from preclinical drug parameters routinely available during discovery and development pathways. PMID:24647103

  15. Integrated flight/propulsion control system design based on a centralized approach

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay; Mattern, Duane L.; Bullard, Randy E.

    1989-01-01

    An integrated flight/propulsion control system design is presented for the piloted longitudinal landing task with a modern, statically unstable, fighter aircraft. A centralized compensator based on the Linear Quadratic Gaussian/Loop Transfer Recovery methodology is first obtained to satisfy the feedback loop performance and robustness specificiations. This high-order centralized compensator is then partitioned into airframe and engine sub-controllers based on modal controllability/observability for the compensator modes. The order of the sub-controllers is then reduced using internally-balanced realization techniques and the sub-controllers are simplified by neglecting the insignificant feedbacks. These sub-controllers have the advantage that they can be implemented as separate controllers on the airframe and the engine while still retaining the important performance and stability characteristics of the full-order centralized compensator. Command prefilters are then designed for the closed-loop system with the simplified sub-controllers to obtain the desired system response to airframe and engine command inputs, and the overall system performance evaluation results are presented.

  16. Quantitative analysis of the central-chest lymph nodes based on 3D MDCT image data

    NASA Astrophysics Data System (ADS)

    Lu, Kongkuo; Bascom, Rebecca; Mahraj, Rickhesvar P. M.; Higgins, William E.

    2009-02-01

    Lung cancer is the leading cause of cancer death in the United States. In lung-cancer staging, central-chest lymph nodes and associated nodal stations, as observed in three-dimensional (3D) multidetector CT (MDCT) scans, play a vital role. However, little work has been done in relation to lymph nodes, based on MDCT data, due to the complicated phenomena that give rise to them. Using our custom computer-based system for 3D MDCT-based pulmonary lymph-node analysis, we conduct a detailed study of lymph nodes as depicted in 3D MDCT scans. In this work, the Mountain lymph-node stations are automatically defined by the system. These defined stations, in conjunction with our system's image processing and visualization tools, facilitate lymph-node detection, classification, and segmentation. An expert pulmonologist, chest radiologist, and trained technician verified the accuracy of the automatically defined stations and indicated observable lymph nodes. Next, using semi-automatic tools in our system, we defined all indicated nodes. Finally, we performed a global quantitative analysis of the characteristics of the observed nodes and stations. This study drew upon a database of 32 human MDCT chest scans. 320 Mountain-based stations (10 per scan) and 852 pulmonary lymph nodes were defined overall from this database. Based on the numerical results, over 90% of the automatically defined stations were deemed accurate. This paper also presents a detailed summary of central-chest lymph-node characteristics for the first time.

  17. Accentuated lines in the enamel of primary incisors from skeletal remains: A contribution to the explanation of early childhood mortality in a medieval population from Poland.

    PubMed

    Żądzińska, Elżbieta; Lorkiewicz, Wiesław; Kurek, Marta; Borowska-Strugińska, Beata

    2015-07-01

    Physiological disruptions resulting from an impoverished environment during the first years of life are of key importance for the health and biological status of individuals and populations. Studies of growth processes in archaeological populations point to the fact that the main causes of childhood mortality in the past are to be sought among extrinsic factors. Based on this assumption, one would expect random mortality of children, with the deceased individuals representing the entire subadult population. The purpose of this study is to explore whether differences in early childhood survival are reflected in differences in deciduous tooth enamel, which can provide an insight into the development of an individual during prenatal and perinatal ontogeny. Deciduous incisors were taken from 83 individuals aged 2.0-6.5 years from a medieval inhumation cemetery dated AD 1300-1600. Prenatal and postnatal enamel formation time, neonatal line width, and the number of accentuated lines were measured using an optical microscope. The significantly wider neonatal line and the higher frequency of accentuated lines in the enamel of the incisors of children who died at the age of 2-3 years suggest the occurrence of stronger or more frequent stress events in this group. These results indicate that in skeletal populations mortality was not exclusively determined by random external factors. Individuals predisposed by an unfavorable course of prenatal and perinatal growth were more likely to die in early childhood. PMID:25711723

  18. Systematic review of changes in maxillary incisor exposure and upper lip position with Le Fort I type osteotomies with or without cinch sutures and/or VY closures.

    PubMed

    Khamashta-Ledezma, L; Naini, F B

    2014-01-01

    The aim was to systematically review the maxillary incisor exposure and upper lip position changes with Le Fort I type osteotomies for advancement ± impaction with rigid internal fixation, taking into account the use of cinch sutures and VY closures. Electronic databases (Cochrane Library, Medline, Embase, and Web of Science) were searched using medical subject headings (MeSH), key words, truncations, and Boolean operators. Hand searching was also undertaken. Of 979 articles identified, 15 were included (11 retrospective, two prospective, and two unspecified). Relevant study details and outcomes were recorded on a spreadsheet, along with an assessment of their quality. In total, these studies assessed 419 patients (266 female, 118 male) with a mean age of 26.4 years (range 14-57 years). Soft tissue changes were assessed on lateral cephalometric radiographs. The mean maxillary hard tissue advancement and impaction ranged between 0.94 and 8.77 mm and -0.56 and 4.2 mm, respectively. The ranges of ratios demonstrated that from pronasale (0.24-0.35) to labrale superius (0.36-1.43), the soft tissues followed the underlying horizontal hard tissue movement increasingly more closely. Alar base cinch sutures and VY closures tended to increase these ratios. The soft tissue response was more variable vertically. None of the studies reported on maxillary incisor exposure change. More good quality prospective studies are needed. PMID:24103543

  19. Centralized, decentralized, and independent control of a flexible manipulator on a flexible base

    NASA Technical Reports Server (NTRS)

    Li, Feiyue; Bainum, Peter M.; Xu, Jianke

    1991-01-01

    The dynamics and control of a flexible manipulator arm with payload mass on a flexible base in space are considered. The controllers are provided by one torquer at the center of the base and one torquer at the connection joint of the robot and the base. The nonlinear dynamics of the system is modeled by applying the finite element method and Lagrangian formula. Three control strategies are considered and compared, i.e., centralized control, decentralized control, and independent control. All these control designs are based on the linear quadratic regulator theory. A mathematical decomposition is used in the decentralization process so that the coupling between the subsystems is weak, while a physical decomposition is used in the independent control design process. For both the decentralized and the independent controls, the stability of the overall linear system is checked before a numerical simulations is initiated. Two numerical examples show that the response of the independent control system are close to those of the centralized control system, while the responses of the decentralized control system are not.

  20. Assessing the ecological base and peak flow of the alpine streams in Central Taiwan

    NASA Astrophysics Data System (ADS)

    Wei, C.; Yang, P. S.; Tian, P. L.

    2009-04-01

    The ecological base and peak flow are crucial for the assessment and design for habitat rehabilitation and recovery. The amount of discharge affects the aquatic creatures and may severely damage the existence and balance of the community under extreme conditions. Aquatic insects are selected as the target species in this study to evaluate the influence of the discharge and to estimate the ecological base and peak flow. The distribution of the number of species and abundance (density) versus discharge is assessed to define the critical discharge. Two streams located at the alpine area in central Taiwan are selected as the study area to evaluate the base and peak flow. From the preliminary data (Aug 2008 to Dec 2008) collected from one stream Creek C originating from Sitou Area in Central Taiwan shows that the abundance of several species varies with the discharge. The dominate family and genus of aquatic insects is Baetidae (Order Ephemeroptera) and Baetis spp. that accounts for 32.47% and 31.11%, respectively. The Hilsenhoff family biotic index (FBI) shows that the water quality is classified to "Good" and "Very Good" level while the river pollution index (RPI) indicates that the stream is non-polluted. The discharge of base flow interpreted from the 95% curve of duration for the daily discharge is 0.0234 cms. Consistent observations are yet to be collected to yield more accurate result and ecological peak flow in rainy and typhoon seasons.

  1. A multidisciplinary treatment of congenitally missing maxillary lateral incisors: a 14-year follow-up case report

    PubMed Central

    de ALMEIDA, Renato Rodrigues; MORANDINI, Ana Carolina Faria; de ALMEIDA-PEDRIN, Renata Rodrigues; de ALMEIDA, Marcio Rodrigues; CASTRO, Renata Cristina Faria Ribeiro; INSABRALDE, Natalia Martins

    2014-01-01

    Absence of the maxillary lateral incisor creates an aesthetic problem which can be managed in various ways. The condition requires careful treatment planning and consideration of the options and outcomes following either space closure or prosthetic replacement. Recent developments in restorative dentistry have warranted a re-evaluation of the approach to this clinical situation. Factors relating both to the patient and the teeth, including the presentation of malocclusion and the effect on the occlusion must be considered. The objective of this study was to describe the etiology, prevalence and alternative treatment modalities for dental agenesis and to present a clinical case of agenesis of the maxillary lateral incisors treated by the closure of excessive spaces and canine re-anatomization. A clinical case is presented to illustrate the interdisciplinary approach between orthodontics and restorative dentistry for improved esthetic results. In this report, the treatment of a girl with a Class II malocclusion of molars and canines with missing maxillary lateral incisors and convex facial profile is shown. Treatment was successfully achieved and included the space closure of the areas corresponding to the missing upper lateral incisors, through movement of the canines and the posterior teeth to mesial by fixed appliances as well as the canines transformation in the maxillary lateral incisors. This is a 14-year follow-up case report involving orthodontics and restorative dentistry in which pretreatment, post-treatment, and long-term follow-up records for the patient are presented. PMID:25466480

  2. Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases

    SciTech Connect

    Thiessen, R.L.; Eliason, J.R.; Johnson, L.K.; Brougher, C.W.; Foley, M.G.; Beaver, D.E.

    1991-08-01

    Interest in the Hanford site (Washington) as a nuclear production, power, and waste disposal site has led to generation of a vast quantity of geophysical and remote sensing data sets of the central Columbia Plateau. To data, these various studies, including at least 13 independent magnetic linear and image lineament studies, have not been adequately correlated. Therefore, these studies provide a unique opportunity to compare and contrast the viability of the different geophysical and remote sensing techniques. The geology of the central Columbia Plateau is characterized by subdued topography and limited outcrop, with most of the exposure concentrated in localized folded/faulted mountains (the Yakima folds) and along river canyons. In order to efficiently compare lineament data bases, we have written an automated computer routine that correlated lineaments that are within a user specified distance of each other. The angle between their trends has to be less than an input maximum separation angle. If more than two lineament maps exist for the area, the analyst may also specify the minimum number of times each structure must be seen. The lineament correlation routine was applied to data bases of all aeromagnetic linears as well as lineaments seen on radar and a digital elevation model DEM image. Geologic structures align with a set of three-dimensional planar structures identified with our Geologic Spatial Analysis (GSA) system. The GSA analysis is based upon computer automated detection of valley bottoms as defined by a DEM.

  3. Centralized PI control for high dimensional multivariable systems based on equivalent transfer function.

    PubMed

    Luan, Xiaoli; Chen, Qiang; Liu, Fei

    2014-09-01

    This article presents a new scheme to design full matrix controller for high dimensional multivariable processes based on equivalent transfer function (ETF). Differing from existing ETF method, the proposed ETF is derived directly by exploiting the relationship between the equivalent closed-loop transfer function and the inverse of open-loop transfer function. Based on the obtained ETF, the full matrix controller is designed utilizing the existing PI tuning rules. The new proposed ETF model can more accurately represent the original processes. Furthermore, the full matrix centralized controller design method proposed in this paper is applicable to high dimensional multivariable systems with satisfactory performance. Comparison with other multivariable controllers shows that the designed ETF based controller is superior with respect to design-complexity and obtained performance. PMID:24954810

  4. Central FPGA-based destination and load control in the LHCb MHz event readout

    NASA Astrophysics Data System (ADS)

    Jacobsson, R.

    2012-10-01

    The readout strategy of the LHCb experiment is based on complete event readout at 1 MHz. A set of 320 sub-detector readout boards transmit event fragments at total rate of 24.6 MHz at a bandwidth usage of up to 70 GB/s over a commercial switching network based on Gigabit Ethernet to a distributed event building and high-level trigger processing farm with 1470 individual multi-core computer nodes. In the original specifications, the readout was based on a pure push protocol. This paper describes the proposal, implementation, and experience of a non-conventional mixture of a push and a pull protocol, akin to credit-based flow control. An FPGA-based central master module, partly operating at the LHC bunch clock frequency of 40.08 MHz and partly at a double clock speed, is in charge of the entire trigger and readout control from the front-end electronics up to the high-level trigger farm. One FPGA is dedicated to controlling the event fragment packing in the readout boards, the assignment of the farm node destination for each event, and controls the farm load based on an asynchronous pull mechanism from each farm node. This dynamic readout scheme relies on generic event requests and the concept of node credit allowing load control and trigger rate regulation as a function of the global farm load. It also allows the vital task of fast central monitoring and automatic recovery in-flight of failing nodes while maintaining dead-time and event loss at a minimum. This paper demonstrates the strength and suitability of implementing this real-time task for a very large distributed system in an FPGA where no random delays are introduced, and where extreme reliability and accurate event accounting are fundamental requirements. It was in use during the entire commissioning phase of LHCb and has been in faultless operation during the first two years of physics luminosity data taking.

  5. Early Diagnosis of Bilateral Supplemental Primary and Permanent Maxillary Lateral Incisors: A Case Report

    PubMed Central

    Yildirim, Gozde; Bayrak, Sule

    2011-01-01

    Supernumerary teeth occur frequently in permanent dentition, but they are rarely found in primary dentition. Supernumerary teeth of orthodox shape and size that resemble normal dentition are called ‘supplemental teeth’. Supplemental teeth are less common than supernumerary teeth and are often overlooked because of their normal shape and size. Supplemental teeth may cause esthetic problems, delayed eruption and crowding, and they require early diagnosis and treatment to prevent complications. The case reported here is one of bilateral supplemental teeth impeding the eruption of permanent maxillary lateral incisors, and it emphasizes the importance of early diagnosis and treatment during early mixed dentition. PMID:21494392

  6. Mandibular lateral incisor with Vertucci Type IV root canal morphological system: A rare case report

    PubMed Central

    Aggarwal, Kanika

    2016-01-01

    Abnormalities in the root canal anatomy are commonly occurring phenomenon. A thorough knowledge of root canal anatomy and its variation is necessary for successful completion of endodontic treatment. Mandibular anteriors are known for having extra canals. The role of genetics and racial variations may result in difference of incidence of root number and canal number. This paper attempts at explaining a rare case of successful endodontic management of two-rooted lateral incisor with awareness of data pertaining to number of canals, knowledge of canal morphology, correct radiographic interpretation, and tactile examination of canal wall which are important in detecting the presence of multiple canals. PMID:27003981

  7. Orthodontic-associated localized gingival recession of lower incisors: who should treat it?

    PubMed

    Chaushu, Stella; Stabholz, Ayala

    2013-07-01

    Gingival recession of lower incisors in the young population has become more prevalent in association with the increased uptake of orthodontic treatment. The two main predisposing factors are thin gingival biotype and bone dehiscence caused by labially displaced roots. Management is sometimes challenging, and the achievement of a successful result requires close cooperation between the orthodontist and periodontist. This article proposes a decision tree, which includes both orthodontic and periodontal considerations, to help the clinician in making the correct diagnosis and choosing the most suitable treatment in post-orthodontic gingival recessions. PMID:24568245

  8. Management of avulsed permanent incisors with closed apices and prolonged extraoral dry time.

    PubMed

    Ritwik, Priyanshi; Langha, Yunus; Musselman, Robert J

    2012-10-01

    This article reports the clinical management and outcome of two avulsed permanent incisors that were kept dry for 42 hours. Dental trauma guidelines were followed and clinically successful outcomes were seen until seven months of follow-up. The factors contributing to successful management of this case despite the extreme clinical circumstances were attributed to pulp extirpation prior to replantation, doxycycline soak, fluoride soak, and timely endodontic treatment. Recent advances and alternate treatment modalities reported in literature are evaluated in the discussion. PMID:23316562

  9. Central obesity in Yemeni children: A population based cross-sectional study

    PubMed Central

    Bamoshmoosh, Mohamed; Massetti, Luciano; Aklan, Hameed; Al-Karewany, Mahdi; Goshae, Husni Al; Modesti, Pietro Amedeo

    2013-01-01

    AIM: To establish percentile curves and to explore prevalence and correlates of central obesity among Yemeni children in a population based cross-sectional study. METHODS: A representative sample of 3114 Yemeni children (1564 boys, 1550 girls) aged 6-19 years participating in the HYpertension and Diabetes in Yemen study was studied. Data collection was conducted at home by survey teams composed of two investigators of both genders. Study questionnaire included questions about demographics, lifestyle, and medical history. Anthropometric measurements included body weight, height, waist circumference (WC) and hip circumferences. Waist to hip ratio (WHR) and waist-to-height ratio (WHtR) were then calculated. Age and gender specific smoothed percentiles of WC, WHR, and WHtR were obtained using lambda-mu-sigma parameters (LMS method). The independent predictors of central obesity defined as (1) WC percentile ≥ 90th; (2) WHtR ≥ 0.5; or (3) WC percentile ≥ 90th and WHtR ≥ 0.5, were identified at multivariate logistic regression analysis adjusted for age, gender, urban/rural location, years of school education, sedentary/active life-style. RESULTS: Percentile curves for WC, WHR and WHtR are presented. Average WC increased with age for both genders. Boys had a higher WC than girls until early adolescence and thereafter girls had higher values than boys. WHR decreased both in boys and girls until early adolescence. Thereafter while in boys it plateaued in girls it continued to decrease. Mean WHtR decreased until early adolescence with no gender related differences and thereafter increased more in girls than in boys towards adult age. Prevalence of central obesity largely varied according to the definition used which was 10.9% for WC ≥ 90th percentile, 18.3% for WHtR ≥ 0.5, and 8.6% when fulfilling both criteria. At adjusted logistic regression WC ≥ 90th percentiles and WHtR ≥ 0.5 were less prevalent in rural than in urban areas (OR = 0.52, 95%CI: 0.41-0.67 and 0.66, 0.54-0.79 respectively), being more prevalent in children with sedentary lifestyle rather than an active one (1.52, 95%CI: 1.17-1.98 and 1.42, 95%CI: 1.14-1.75, respectively). CONCLUSION: Yemeni children central obesity indices percentile curves are presented. Central obesity prevalence varied according to the definition used and was more prevalent in urban sedentary subjects. PMID:24009819

  10. New approaches to solve old water problems: community based organizations in Central Asia

    NASA Astrophysics Data System (ADS)

    Nurymgereyev, Kanysh

    2010-05-01

    The dry summer of 2009 has once again shown unsteadiness of economy of the Central-Asian countries, first of all, in agricultural sector and serious dependence of the region on water resources. For example, decreasing of water level in Toktogul reservoir forces the Government of the Kyrgyz Republic, the country where the largest rivers of the Central Asia originate, to the systematic switching-off of the electricity in three regions. Already in the spring of 2009, the experts predicted decreasing of gross production of agriculture in region, especially for the main cultures of cotton and rice. Coupled by natural cataclysms, the problems with water resources management have seriously aggravated conditions that are directly reflected on the livelihood of the rural population of Central Asia. This demands a search for new approaches and methods of solution of the main problems of water resources management. Despite the fact that the main issues of water distribution are solved at a level of the governments of the countries of Central Asia, a serious role in this process is associated directly to local water users. In recent years in some countries of the region, a process of creation of new community based Institutes of water resources management like Water Users Associations of (WUA) has started. The main idea for creation of these organizations is the necessity to involve the local water users like farmers to the process of water resources management and distribution. However, activity of the WUAs in the region has shown certain weaknesses both regarding the legal status of these organizations and institutional development. The main weakness of many WUAs is a lack of opportunities and mechanisms of involving of associations in decision-making processes. Members of WUAs have an opportunity to participate in distribution of water only within the borders of the associations while the main requirement of efficient water resources management is the principle of the integrated water management. The essence of this principle is that issues of water use and water distribution should be solved in coordination and in view of interests of all partners from other countries of the region. The next important issue is the necessity to strengthen the institutional capacity of WUAs. First of all, it is related to providing new approaches in training of members of associations in organizational management, fundraising, and modern technologies of natural resources management. It would be useful as well to strengthen cooperation between WUAs of neighboring countries in order to create information exchange and distribution of best practices between them. Hence, cooperation between the WUAs of the Central Asia countries could become an example for local governments for an integrated solution of problems of distribution and water resources management in the region.

  11. Base Excision Repair in Physiology and Pathology of the Central Nervous System

    PubMed Central

    Bosshard, Matthias; Markkanen, Enni; van Loon, Barbara

    2012-01-01

    Relatively low levels of antioxidant enzymes and high oxygen metabolism result in formation of numerous oxidized DNA lesions in the tissues of the central nervous system. Accumulation of damage in the DNA, due to continuous genotoxic stress, has been linked to both aging and the development of various neurodegenerative disorders. Different DNA repair pathways have evolved to successfully act on damaged DNA and prevent genomic instability. The predominant and essential DNA repair pathway for the removal of small DNA base lesions is base excision repair (BER). In this review we will discuss the current knowledge on the involvement of BER proteins in the maintenance of genetic stability in different brain regions and how changes in the levels of these proteins contribute to aging and the onset of neurodegenerative disorders. PMID:23203191

  12. Mobile devices for community-based REDD+ monitoring: a case study for Central Vietnam.

    PubMed

    Pratihast, Arun Kumar; Herold, Martin; Avitabile, Valerio; de Bruin, Sytze; Bartholomeus, Harm; Souza, Carlos M; Ribbe, Lars

    2012-01-01

    Monitoring tropical deforestation and forest degradation is one of the central elements for the Reduced Emissions from Deforestation and Forest Degradation in developing countries (REDD+) scheme. Current arrangements for monitoring are based on remote sensing and field measurements. Since monitoring is the periodic process of assessing forest stands properties with respect to reference data, adopting the current REDD+ requirements for implementing monitoring at national levels is a challenging task. Recently, the advancement in Information and Communications Technologies (ICT) and mobile devices has enabled local communities to monitor their forest in a basic resource setting such as no or slow internet connection link, limited power supply, etc. Despite the potential, the use of mobile device system for community based monitoring (CBM) is still exceptional and faces implementation challenges. This paper presents an integrated data collection system based on mobile devices that streamlines the community-based forest monitoring data collection, transmission and visualization process. This paper also assesses the accuracy and reliability of CBM data and proposes a way to fit them into national REDD+ Monitoring, Reporting and Verification (MRV) scheme. The system performance is evaluated at Tra Bui commune, Quang Nam province, Central Vietnam, where forest carbon and change activities were tracked. The results show that the local community is able to provide data with accuracy comparable to expert measurements (index of agreement greater than 0.88), but against lower costs. Furthermore, the results confirm that communities are more effective to monitor small scale forest degradation due to subsistence fuel wood collection and selective logging, than high resolution remote sensing SPOT imagery. PMID:23344371

  13. Mobile Devices for Community-Based REDD+ Monitoring: A Case Study for Central Vietnam

    PubMed Central

    Pratihast, Arun Kumar; Herold, Martin; Avitabile, Valerio; de Bruin, Sytze; Bartholomeus, Harm; Souza, Carlos M.; Ribbe, Lars

    2013-01-01

    Monitoring tropical deforestation and forest degradation is one of the central elements for the Reduced Emissions from Deforestation and Forest Degradation in developing countries (REDD+) scheme. Current arrangements for monitoring are based on remote sensing and field measurements. Since monitoring is the periodic process of assessing forest stands properties with respect to reference data, adopting the current REDD+ requirements for implementing monitoring at national levels is a challenging task. Recently, the advancement in Information and Communications Technologies (ICT) and mobile devices has enabled local communities to monitor their forest in a basic resource setting such as no or slow internet connection link, limited power supply, etc. Despite the potential, the use of mobile device system for community based monitoring (CBM) is still exceptional and faces implementation challenges. This paper presents an integrated data collection system based on mobile devices that streamlines the community-based forest monitoring data collection, transmission and visualization process. This paper also assesses the accuracy and reliability of CBM data and proposes a way to fit them into national REDD+ Monitoring, Reporting and Verification (MRV) scheme. The system performance is evaluated at Tra Bui commune, Quang Nam province, Central Vietnam, where forest carbon and change activities were tracked. The results show that the local community is able to provide data with accuracy comparable to expert measurements (index of agreement greater than 0.88), but against lower costs. Furthermore, the results confirm that communities are more effective to monitor small scale forest degradation due to subsistence fuel wood collection and selective logging, than high resolution remote sensing SPOT imagery. PMID:23344371

  14. A Comparison of a Centralized Versus De-Centralized Recruitment Schema in Two Community-Based Participatory Research Studies for Cancer Prevention

    PubMed Central

    Adams, Swann Arp; Heiney, Sue P.; Brandt, Heather M.; Wirth, Michael D.; Khan, Samira; Johnson, Hiluv; Davis, Lisa; Wineglass, Cassandra M.; Warren-Jones, Tatiana Y.; Felder, Tisha M.; Drayton, Ruby F.; Davis, Briana; Farr, Deeonna E.; Hébert, James R.

    2014-01-01

    Use of community-based participatory research (CBPR) approaches is increasing with the goal of making more meaningful and impactful advances in eliminating cancer-related health disparities. While many reports have espoused its advantages, few investigations have focused on comparing CBPR-oriented recruitment and retention. Consequently, the purpose of this analysis was to report and compare two different CBPR approaches in two cancer prevention studies. We utilized frequencies and chi-squared tests to compare and contrast subject recruitment and retention for two studies that incorporated a randomized, controlled intervention design of a dietary and physical activity intervention among African Americans. One study utilized a de-centralized approach to recruitment in which primary responsibility for recruitment was assigned to the general AA community of various church partners whereas the other incorporated a centralized approach to recruitment in which a single lay community individual was hired as research personnel to lead recruitment and intervention delivery. Both studies performed equally well for both recruitment and retention (75 and 88% recruitment rates and 71 and 66% retention rates) far exceeding those rates traditionally cited for cancer clinical trials (~5%). The de-centralized approach to retention appeared to result in statistically greater retention for the control participants compared to the centralized approach (77 vs 51%, P<0.01). Consequently, both CBPR approaches appeared to greatly enhance recruitment and retention rates of AA populations. We further note lessons learned and challenges to consider for future research opportunities. PMID:25086566

  15. Theoretical Study of the Effect of Enamel Parameters on Laser-Induced Surface Acoustic Waves in Human Incisor

    NASA Astrophysics Data System (ADS)

    Yuan, Ling; Sun, Kaihua; Shen, Zhonghua; Ni, Xiaowu; Lu, Jian

    2015-06-01

    The laser ultrasound technique has great potential for clinical diagnosis of teeth because of its many advantages. To study laser surface acoustic wave (LSAW) propagation in human teeth, two theoretical methods, the finite element method (FEM) and Laguerre polynomial extension method (LPEM), are presented. The full field temperature values and SAW displacements in an incisor can be obtained by the FEM. The SAW phase velocity in a healthy incisor and dental caries is obtained by the LPEM. The methods and results of this work can provide a theoretical basis for nondestructive evaluation of human teeth with LSAWs.

  16. Retreatment of a Maxillary Lateral Incisor With Two Separate Root Canals Confirmed With Cone Beam Computed Tomography

    PubMed Central

    Aydemir, Seda; Helvacioglu-Yigit, Dilek; Sinanoglu, Alper; Ozel, Emre

    2015-01-01

    The purpose of this report is to present a rare case of a maxillary lateral incisor exhibiting two separate root canals confirmed by cone-beam computed tomography (CBCT). A 65-year-old female patient with an esthetic complaint regarding her maxillary left lateral incisor was referred to our clinic. During a radiographical examination, an endodontically treated root canal and an extra root canal with an apical lesion were observed. The retreatment was performed. CBCT findings confirmed the root canal mophology of the maxillary left lateral with two distinct canals. We conclude that the CBCT imaging is an adjunctive tool for better assessment of complex root canal systems. PMID:26015823

  17. Investigation of lay knowledge of the management of avulsed permanent incisors.

    PubMed

    Hamilton, F A; Hill, F J; Mackie, I C

    1997-02-01

    The prognosis of replanted avulsed permanent incisors depends largely on prompt and appropriate emergency management. The aim of this study was to investigate lay knowledge and attitudes in this respect. Postal questionnaires were sent to all physical education teachers, school nurses and secretaries, attendants in swimming baths and leisure centres and to 220 parents of teenage children in a defined area of North West England. The overall questionnaire response rate was 86.9%. Knowledge of methods of dealing with this problem was generally inadequate in both parents and the other groups. Although 53.6% of respondents claimed to have received first aid training only 3.1% could remember dental injuries being included. There was evidence that dental health education in this field can be effective, since the highest mean knowledge score was found in the 11.5% of respondents who recalled receiving advice from sources such as posters, magazines and newspapers. More than 80% of the respondents stated that they would not want to replant an avulsed incisor themselves, the main reason being lack of knowledge and training. It is suggested that there is a need for potentially effective dental health education in relation to this problem. PMID:9206384

  18. Adaptive diversity of incisor enamel microstructure in South American burrowing rodents (family Ctenomyidae, Caviomorpha)

    PubMed Central

    Vieytes, Emma C; Morgan, Cecilia C; Verzi, Diego H

    2007-01-01

    The aim of this study was to analyse the morphofunctional and adaptive significance of variation in the upper incisor enamel microstructure of South American burrowing ctenomyids and other octodontoid taxa. We studied the specialized subterranean tooth-digger †Eucelophorus chapalmalensis (Pliocene – Middle Pleistocene), and compared it with other fossil and living ctenomyids with disparate digging adaptations, two fossorial octodontids and one arboreal echimyid. Morphofunctionally significant enamel traits were quite similar among the species studied despite their marked differences in habits, digging behaviour and substrates occupied, suggesting a possible phylogenetic constraint for the Octodontoidea. In this context of relative similarity, the inclination of Hunter–Schreger bands, relative thickness of external index (EI) and prismless enamel zone were highest in †Eucelophorus, in agreement with its outstanding craniomandibular tooth-digging specialization. Higher inclination of Hunter–Schreger bands reinforces enamel to withstand high tension forces, while high external index provides greater resistance to wear. Results suggest increased frequency of incisor use for digging in †Eucelophorus, which could be related to a more extreme tooth-digging strategy and/or occupancy of hard soils. Higher external index values as recurring patterns in distant clades of tooth-digging rodents support an adaptive significance of this enamel trait. PMID:17584181

  19. Prevalence of lesions in incisors of mule deer from Colorado Springs, Colorado

    SciTech Connect

    Borrero, L.M.; Scanlon, P.F.

    1995-12-31

    Lesions in teeth may be influenced by exposure to fluorides, malnutrition and trauma. Incisors of 228 mule deer (Odocoileus hemionus) taken from the USAF Academy, Colorado Springs, CO during the 1993 hunting season were examined for lesions. A classification scheme (scale = 0--5) for lesions was derived from the method of Shupe et al. 1963. Lesions were present in at least one incisor of 84.6% of deer. Of the deer with lesions, 86% had at least one tooth with very slight effect (one to few white spots), 9.8% had a slight effect (generalized mottling), 2.6% had a moderate effect (generalized mottling and wear), 10.04% had a marked effect (mottling and hypoplasia of the enamel) , and 0.5 % ad severe effects (hypoplasia of the enamel and abnormal wear). Lesions that affect the enamel are produced during the period of formation of the tooth. The severity of lesions depends on the cause and the length of exposure to the causative agent. Generally mottling and hypoplasia of the enamel are associated with fluorosis. The relationship of lesions to bone and tooth fluoride concentrations was examined.

  20. Vesicular glutamate transporter immunoreactivity in the periodontal ligament of the rat incisor.

    PubMed

    Honma, Shiho; Kato, Akiko; Shi, Lei; Yatani, Hirofumi; Wakisaka, Satoshi

    2012-01-01

    The distribution of three vesicular glutamate transporter (VGluT) isoforms, VGluT1, VGluT2, and VGluT3, were investigated in the trigeminal ganglion of the periodontal ligament in the rat incisor-a receptive field of trigeminal ganglion neurons. In the trigeminal ganglion, mRNAs for all VGluT isoforms were detected and proteins were observed in the cytoplasm of trigeminal ganglion cells. VGluT1 immunoreactions were localized within the cytoplasm for all sizes of trigeminal neurons, although predominately in medium-large trigeminal neurons. Double-labeling showed that most VGluT1 contained both VGluT2 and VGluT3. In the periodontal ligament of the incisor, the Ruffini endings, principal periodontal mechanoreceptors, displayed VGluT1 and VGluT2 immunoreactivities. However, lacked immunoreactions for VGluT3. At the electron microscopic level, VGluT1 immunoreactions were localized around the vesicle membranes at the axon terminal of Ruffini endings. The present results indicate that VGluT is expressed in the sensory nerve endings where apparent synapses are not present. Thus, glutamate in the sensory nerve endings is thought to be used in metabotropic functions. This is because glutamate is a general metabolic substrate, and/or acts as a neurotransmitter as proposed in muscle spindles. PMID:21957077

  1. Shear bond strength of dentin and deproteinized enamel of AI mouse incisors

    PubMed Central

    Pugach, M.K.; Ozer, F.; Mulmadgi, R.; Li, Y.; Suggs, C.; Wright, J.T.; Bartlett, J.D.; Gibson, C.W.; Lindemeyer, R.G.

    2014-01-01

    Purpose To investigate the adhesion through shear bond strength (SBS) testing of a resin composite bonded with a self-etching bonding system (SEB) to amelogenesis imperfecta (AI)-affected deproteinized mouse enamel or dentin; and to compare wild-type (WT), amelogenin null (AmelxKO) and matrix metalloproteinase-20 null (Mmp20KO) enamel and dentin phenotypes using microCT and nanoindentation. Methods Enamel incisor surfaces of WT, AmelxKO and Mmp20KO mice were treated with SEB with and without NaOCl and tested for SBS. Incisor dentin was also treated with SEB and tested for SBS. These surfaces were further examined by SEM. MicroCT and nanoindentation analyses were performed on mouse dentin and enamel. Data were analyzed for significance by ANOVA. Results Deproteinization did not improve SBS of SEB to these AI-affected enamel surfaces. SBS of AmelxKO teeth was similar in dentin and enamel; however, it was higher in Mmp20KO dentin. The nanohardness of knockout enamel was significantly lower than WT, while knockout dentin nanohardness was not different from WT. Conclusions Using animal AI models, it was demonstrated that enamel NaOCl deproteinization of hypoplastic and hypoplastic-hypomaturation enamel did not increase shear bond strength while removal of the defective enamel allowed optimal dentin bonding. PMID:25303500

  2. Incisor size and community structure in rodents: Two tests of the role of competition

    NASA Astrophysics Data System (ADS)

    Parra, Virginie; Loreau, Michel; Jaeger, Jean-Jacques

    1999-04-01

    We used two different approaches to test for the effect of interspecific competition on community-wide patterns in the size of the upper incisor in six rodent communities. One tests for constancy of size ratios between adjacent species (Barton and David's test), and the other tests for minimum mean size overlap between species pairs (randomization test). The results of the two tests were more congruent for the radius of the upper incisor than for its diameter. Although a number of tests gave significant results, they led to a consistent rejection of the null hypothesis of a randomly generated pattern only in two communities from an African rainforest. Many factors are likely to disturb community structure, among which we identify recent species introductions and the presence of rare species. Our results also show that Hutchinson's rule of a limiting size similarity does not hold; the mean size ratio between adjacent species was correlated with the overall size range and the number of species in a community.

  3. CENTERA: A Centralized Trust-Based Efficient Routing Protocol with Authentication for Wireless Sensor Networks †

    PubMed Central

    Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim

    2015-01-01

    In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of “bad” nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics—maliciousness, cooperation, and compatibility—and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates “bad”, “misbehaving” or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated “bad” behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to “good” nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations. PMID:25648712

  4. CENTERA: a centralized trust-based efficient routing protocol with authentication for wireless sensor networks.

    PubMed

    Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim

    2015-01-01

    In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of "bad" nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics-maliciousness, cooperation, and compatibility-and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates "bad", "misbehaving" or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated "bad" behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to "good" nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations. PMID:25648712

  5. Branch-Based Centralized Data Collection for Smart Grids Using Wireless Sensor Networks

    PubMed Central

    Kim, Kwangsoo; Jin, Seong-il

    2015-01-01

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method. PMID:26007734

  6. Branch-based centralized data collection for smart grids using wireless sensor networks.

    PubMed

    Kim, Kwangsoo; Jin, Seong-il

    2015-01-01

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method. PMID:26007734

  7. [Central neurobiological mechanism of liver depression and spleen deficiency syndrome based on chronic stress: a review].

    PubMed

    Li, Xiao-hong; Li, Jing-jing; Liu, Yue-yun; Chen, Jia-xu

    2012-01-01

    Some researchers focus on research of the nature of syndromes. The methods of combining traditional Chinese medicine syndrome and diseases and the correspondence between formulas and syndromes may be used in research of the nature of syndromes. According to combined theories of zang-organ state and seven emotions in traditional Chinese medicine with stress theory in modern medicine, the authors applied the methods of chronic immobilization stress to induce liver depression and spleen deficiency syndrome in rats based on the thinking of relativity on formula and syndrome. The research showed that the central neurobiology mechanism of liver depression and spleen deficiency syndrome closely correlates to the hypothalamic-pituitary-adrenal axis, brain-gut axis, myriad central neurotrophic factors, neurotransmitters, neuropeptides and hormones and their receptors, involving in many encephalic regions such as the hypothalamus, hippocampus, cortex, amygdale, etc. The authors will combine their previous work with multi-disciplinary research, such as genomics, proteomics, metabolomics and bioinformatics in future studies, to reveal the scientific connotations of liver depression and spleen deficiency syndrome. PMID:22237267

  8. Physics-based real time ground motion parameter maps: the Central Mexico example

    NASA Astrophysics Data System (ADS)

    Ramirez Guzman, L.; Contreras Ruiz Esparza, M. G.; Quiroz Ramirez, A.; Carrillo Lucia, M. A.; Perez Yanez, C.

    2013-12-01

    We present the use of near real time ground motion simulations in the generation of ground motion parameter maps for Central Mexico. Simple algorithm approaches to predict ground motion parameters of civil protection and risk engineering interest are based on the use of observed instrumental values, reported macroseismic intensities and their correlations, and ground motion prediction equations (GMPEs). A remarkable example of the use of this approach is the worldwide Shakemap generation program of the United States Geological Survey (USGS). Nevertheless, simple approaches rely strongly on the availability of instrumental and macroseismic intensity reports, as well as the accuracy of the GMPEs and the site effect amplification calculation. In regions where information is scarce, the GMPEs, a reference value in a mean sense, provide most of the ground motion information together with site effects amplification using a simple parametric approaches (e.g. the use of Vs30), and have proven to be elusive. Here we propose an approach that includes physics-based ground motion predictions (PBGMP) corrected by instrumental information using a Bayesian Kriging approach (Kitanidis, 1983) and apply it to the central region of Mexico. The method assumes: 1) the availability of a large database of low and high frequency Green's functions developed for the region of interest, using fully three-dimensional and representative one-dimension models, 2) enough real time data to obtain the centroid moment tensor and a slip rate function, and 3) a computational infrastructure that can be used to compute the source parameters and generate broadband synthetics in near real time, which will be combined with recorded instrumental data. By using a recently developed velocity model of Central Mexico and an efficient finite element octree-based implementation we generate a database of source-receiver Green's functions, valid to 0.5 Hz, that covers 160 km x 300 km x 700 km of Mexico, including a large portion of the Pacific Mexican subduction zone. A subset of the velocity and strong ground motion data available in real time is processed to obtain the source parameters to generate broadband ground motions in a dense grid ( 10 km x 10 km cells). These are interpolated later with instrumental values using a Bayesian Kriging method. Peak ground velocity and acceleration, as well as SA (T=0.1, 0.5, 1 and 2s) maps, are generated for a small set of medium to large magnitude Mexican earthquakes (Mw=5 to 7.4). We evaluate each map by comparing against stations not considered in the computation.

  9. Efficient crop type mapping based on remote sensing in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Zhong, Liheng

    Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages when the size of the training set is limited by ground truth availability. Once developed, the classifier is able to be applied to different years and a vast area with only a few adjustments according to local agricultural and annual weather conditions. 250 m MODIS imagery is utilized as the main input to the PBC algorithm and displays promising capacity in crop identification in several counties in the Central Valley. A time series of Landsat TM/ETM+ images at a 30 m resolution is necessary in the crop mapping of counties with smaller land parcels, although the processing time is longer. Spectral characteristics are also employed to identify crops in PBC. Spectral signatures are associated with phenological stages instead of imaging dates, which highly increases the stability of the classifier performance and overcomes the problem of over-fitting. Moderate accuracies are achieved by PBC, with confusions mostly within the same crop categories. Based on a quantitative analysis, misclassification in PBC has very trivial impacts on the accuracy of agricultural water use estimate. The cost of the entire PBC procedure is controlled to a very low level, which will enable its usage in routine annual crop mapping in the Central Valley.

  10. Spatial and seasonal variability of base flow in the Verde Valley, central Arizona, 2007 and 2011

    USGS Publications Warehouse

    Garner, Bradley D.; Bills, Donald J.

    2012-01-01

    Synoptic base-flow surveys were conducted on streams in the Verde Valley, central Arizona, in June 2007 and February 2011 by the U.S. Geological Survey (USGS), in cooperation with the Verde River Basin Partnership, the Town of Clarkdale, and Yavapai County. These surveys, also known as seepage runs, measured streamflow under base-flow conditions at many locations over a short period of time. Surveys were conducted on a segment of the Verde River that flows through the Verde Valley, between USGS streamflow-gaging stations 09504000 and 09506000, a distance of 51 river miles. Data from the surveys were used to investigate the dominant controls on Verde River base flow, spatial variability in gaining and losing reaches, and the effects that human alterations have on base flow in the surface-water system. The most prominent human alterations in the Verde Valley are dozens of surface-water diversions from streams, including gravity-fed ditch diversions along the Verde River.Base flow that entered the Verde River from the tributary streams of Oak Creek, Beaver Creek, and West Clear Creek was found to be a major source of base flow in the Verde River. Groundwater discharge directly into the Verde River near these three confluences also was an important contributor of base flow to the Verde River, particularly near the confluence with Beaver Creek. An examination of individual reaches of the Verde River in the Verde Valley found three reaches (largely unaffected by ditch diversions) exhibiting a similar pattern: a small net groundwater discharge in February 2011 (12 cubic feet per second or less) and a small net streamflow loss in June 2007 (11 cubic feet per second or less). Two reaches heavily affected by ditch diversions were difficult to interpret because of the large number of confounding human factors. Possible lower and upper bounds of net groundwater flux were calculated for all reaches, including those heavily affected by ditches.

  11. Satellite-based detection of volcanic sulphur dioxide from recent eruptions in Central and South America

    NASA Astrophysics Data System (ADS)

    Loyola, D.; van Geffen, J.; Valks, P.; Erbertseder, T.; van Roozendael, M.; Thomas, W.; Zimmer, W.; Wißkirchen, K.

    2008-01-01

    Volcanic eruptions can emit large amounts of rock fragments and fine particles (ash) into the atmosphere, as well as several gases, including sulphur dioxide (SO2). These ejecta and emissions are a major natural hazard, not only to the local population, but also to the infrastructure in the vicinity of volcanoes and to aviation. Here, we describe a methodology to retrieve quantitative information about volcanic SO2 plumes from satellite-borne measurements in the UV/Visible spectral range. The combination of a satellite-based SO2 detection scheme and a state-of-the-art 3D trajectory model enables us to confirm the volcanic origin of trace gas signals and to estimate the plume height and the effective emission height. This is demonstrated by case-studies for four selected volcanic eruptions in South and Central America, using the GOME, SCIAMACHY and GOME-2 instruments.

  12. [Study on the control of dynamic artificial limb ankle based on central pattern generator].

    PubMed

    Guo, Xin; Xu, Caiyu; Li, Mingyue; Su, Longtao

    2014-12-01

    In order to obtain the normal gait for the prosthesis-carrier with the change of external environment and gait, we designed a model of dynamic ankle prosthesis and control system and introduced the strategy of central pattern generator (CPG) about the moving trail of dynamic ankle prosthesis. The dynamic parts, which are incorporated in the model of dynamic ankle prosthesis, provide power in order to have anthropic function and character. The tool of Matlab/simulink was used to simulate the strategy. The simulation results showed that the strategy of CPG learn- ing control in this study was effective and could track the reference trail rapidly and fit the moving trail of a person's normal limb. It can make the prosthetic timely regulation and action, enhance the prosthetic intelligence. It has im- portant practical value for intelligent prosthesis development based on this analysis of technology. PMID:25868262

  13. [The Development of Information Centralization and Management Integration System for Monitors Based on Wireless Sensor Network].

    PubMed

    Xu, Xiu; Zhang, Honglei; Li, Yiming; Li, Bin

    2015-07-01

    Developed the information centralization and management integration system for monitors of different brands and models with wireless sensor network technologies such as wireless location and wireless communication, based on the existing wireless network. With adaptive implementation and low cost, the system which possesses the advantages of real-time, efficiency and elaboration is able to collect status and data of the monitors, locate the monitors, and provide services with web server, video server and locating server via local network. Using an intranet computer, the clinical and device management staffs can access the status and parameters of monitors. Applications of this system provide convenience and save human resource for clinical departments, as well as promote the efficiency, accuracy and elaboration for the device management. The successful achievement of this system provides solution for integrated and elaborated management of the mobile devices including ventilator and infusion pump. PMID:26665944

  14. Measuring Long-Term Impact Based on Network Centrality: Unraveling Cinematic Citations

    PubMed Central

    Spitz, Andreas; Horvát, Emőke-Ágnes

    2014-01-01

    Traditional measures of success for film, such as box-office revenue and critical acclaim, lack the ability to quantify long-lasting impact and depend on factors that are largely external to the craft itself. With the growing number of films that are being created and large-scale data becoming available through crowd-sourced online platforms, an endogenous measure of success that is not reliant on manual appraisal is of increasing importance. In this article we propose such a ranking method based on a combination of centrality indices. We apply the method to a network that contains several types of citations between more than 40,000 international feature films. From this network we derive a list of milestone films, which can be considered to constitute the foundations of cinema. In a comparison to various existing lists of ‘greatest’ films, such as personal favourite lists, voting lists, lists of individual experts, and lists deduced from expert polls, the selection of milestone films is more diverse in terms of genres, actors, and main creators. Our results shed light on the potential of a systematic quantitative investigation based on cinematic influences in identifying the most inspiring creations in world cinema. In a broader perspective, we introduce a novel research question to large-scale citation analysis, one of the most intriguing topics that have been at the forefront of scientific enquiries for the past fifty years and have led to the development of various network analytic methods. In doing so, we transfer widely studied approaches from citation analysis to the the newly emerging field of quantification efforts in the arts. The specific contribution of this paper consists in modelling the multidimensional cinematic references as a growing multiplex network and in developing a methodology for the identification of central films in this network. PMID:25295877

  15. Results-Based Financing in Mozambique’s Central Medical Store: A Review After 1 Year

    PubMed Central

    Spisak, Cary; Morgan, Lindsay; Eichler, Rena; Rosen, James; Serumaga, Brian; Wang, Angela

    2016-01-01

    ABSTRACT Background: Public health commodity supply chains are typically weak in low-income countries, partly because they have many disparate yet interdependent functions and components. Approaches to strengthening supply chains in such settings have often fallen short—they address technical weaknesses, but not the incentives that motivate staff to perform better. Methods: We reviewed the first year of a results-based financing (RBF) program in Mozambique, which began in January 2013. The program aimed to improve the performance of the central medical store—Central de Medicamentos e Artigos Medicos (CMAM)—by realigning incentives. We completed in-depth interviews and focus group discussions with 33 key informants, including representatives from CMAM and donor agencies, and collected quantitative data on performance measures and use of funds. Implementation: The RBF agreement linked CMAM performance payments to quarterly results on 5 performance indicators related to supply planning, distribution planning, and warehouse management. RBF is predicated on the theory that a combination of carrot and stick—i.e., shared financial incentives, plus increased accountability for results—will spur changes in behavior. Important design elements: (1) indicators were measured against quarterly targets, and payments were made only for indicators that met those targets; (2) targets were set based on documented performance, at levels that could be reasonably attained, yet pushed for improvement; (3) payment was shared with and dependent on all staff, encouraging teamwork and collaboration; (4) results were validated by verifiable data sources; and (5) CMAM had discretion over how to use the funds. Findings: We found that CMAM’s performance continually improved over baseline and that CMAM achieved many of its performance targets, for example, timely submission of quarterly supply and distribution planning reports. Warehouse indicators, such as inventory management and order fulfillment, proved more challenging but were nonetheless positive. By linking payments to periodic verified results, and giving CMAM discretion over how to spend the funds, the RBF agreement motivated the workforce; focused attention on results; strengthened data collection; encouraged teamwork and innovation; and ultimately strengthened the central supply chain. Conclusion: Policy makers and program managers can use performance incentives to catalyze and leverage existing investments. To further strengthen the approach, such incentive programs can shift attention from quantity to quality indicators, improve verification processes, and aim to institutionalize the approach. PMID:27016552

  16. Situational Lightning Climatologies for Central Florida: Phase IV: Central Florida Flow Regime Based Climatologies of Lightning Probabilities

    NASA Technical Reports Server (NTRS)

    Bauman, William H., III

    2009-01-01

    The threat of lightning is a daily concern during the warm season in Florida. Research has revealed distinct spatial and temporal distributions of lightning occurrence that are strongly influenced by large-scale atmospheric flow regimes. Previously, the Applied Meteorology Unit (AMU) calculated the gridded lightning climatologies based on seven flow regimes over Florida for 1-, 3- and 6-hr intervals in 5-, 10-, 20-, and 30-NM diameter range rings around the Shuttle Landing Facility (SLF) and eight other airfields in the National Weather Service in Melbourne (NWS MLB) county warning area (CWA). In this update to the work, the AMU recalculated the lightning climatologies for using individual lightning strike data to improve the accuracy of the climatologies. The AMU included all data regardless of flow regime as one of the stratifications, added monthly stratifications, added three years of data to the period of record and used modified flow regimes based work from the AMU's Objective Lightning Probability Forecast Tool, Phase II. The AMU made changes so the 5- and 10-NM radius range rings are consistent with the aviation forecast requirements at NWS MLB, while the 20- and 30-NM radius range rings at the SLF assist the Spaceflight Meteorology Group in making forecasts for weather Flight Rule violations during Shuttle landings. The AMU also updated the graphical user interface with the new data.

  17. The economics of a pharmacy-based central intravenous additive service for paediatric patients.

    PubMed

    Armour, D J; Cairns, C J; Costello, I; Riley, S J; Davies, E G

    1996-10-01

    This study was designed to compare the costs of a pharmacy-based Central Intravenous Additive Service (CIVAS) with those of traditional ward-based preparation of intravenous doses for a paediatric population. Labour costs were derived from timings of preparation of individual doses in both the pharmacy and ward by an independent observer. The use of disposables and diluents was recorded and their acquisition costs apportioned to the cost of each dose prepared. Data were collected from 20 CIVAS sessions (501 doses) and 26 ward-based sessions (30 doses). In addition, the costs avoided by the use of part vials in CIVAS was calculated. This was derived from a total of 50 CIVAS sessions. Labour, disposable and diluent costs were significantly lower for CIVAS compared with ward-based preparation (p < 0.001). The ratio of costs per dose [in 1994 pounds sterling] between ward and pharmacy was 2.35:1 (2.51 pounds:1.07 pounds). Sensitivity analysis of the best and worst staff mixes in both locations ranged from 2.3:1 to 4.0:1, always in favour of CIVAS. There were considerable costs avoided in CIVAS from the multiple use of vials; the estimated annual sum derived from the study was 44,000 pounds. In addition, CIVAS was less vulnerable to unanticipated interruptions in work flow than ward-based preparation. CIVAS for children was more economical than traditional ward-based preparation, because of a cost-minimisation effect. Sensitivity analysis showed that these advantages were maintained over a full range of skill mixes. Additionally, significant savings accrued from the multiple use of vials in CIVAS. PMID:10163580

  18. Novel treatment of equine odontoclastic tooth resorption and hypercementosis of incisor teeth in a 22-year-old Arabian mare.

    PubMed

    Grier-Lowe, Candace K; Anthony, James

    2015-08-01

    Equine odontoclastic tooth resorption and hypercementosis is a rarely reported condition in the incisor and canine teeth of older horses. Histologically, there is internal and external resorption of the tooth with formation of excessive cementum. Once lesions become infected or supragingival this condition is very painful. The clinical manifestation, diagnosis and treatment of hypercementosis in an Arabian mare are described. PMID:26246633

  19. The effects of day length, hibernation, and ambient temperature on incisor dentin in the Turkish hamster (Mesocricetus brandti).

    PubMed

    Batavia, Mariska; Nguyen, George; Zucker, Irving

    2013-05-01

    Dentin is deposited on a circadian basis, and daily layers manifest as bands on the medial surfaces of rodent incisors. Hibernation alters dentin deposition, and a distinct hibernation mark has been described on incisor surfaces of several rodent species; the factors that influence the morphology of this mark are poorly understood. We tested the effects of day length, torpor expression, and ambient temperature on incisor surface morphology in Turkish hamsters housed in one of four conditions: long days (LDs) at 22 °C, short days (SDs) at 22 °C, SDs at 5 °C, and SDs at 13 °C. Body temperature was monitored continuously with implanted radio transmitters, and teeth examined postmortem. Teeth of SD hamsters had narrower, less distinct circadian increments than those of LD hamsters, but the width of ultradian increments was similar in both photoperiods. Hibernation at both 5 and 13 °C was associated in most specimens with very narrow, sharply defined dentin increments and increased tooth heterogeneity. Hamsters in SDs at 5 °C that did not hibernate lacked characteristic hibernation increments. At 5 °C, but not 13 °C, the number and cumulative width of hibernation increments were related to number and cumulative duration of periodic arousals. Our results suggest that incremental deposition of dentin in rodent incisors may be a useful trait for characterizing hibernation behavior in both evolutionary and historical contexts. PMID:23233167

  20. Functional and Esthetic Treatment of Lateral Incisor Agenesis with a Mini-Implant in a Young Patient: A Case Report.

    PubMed

    da Costa, Moacir Guilherme; Melgaço, Camilo Aquino; Corrêa-Faria, Patrícia; Marques, Leandro Silva

    2015-01-01

    This article reports the treatment of lateral incisor agenesis in a young patient. Treatment was performed with a mini-implant and a temporary crown. Radiographic and clinical follow up for one year demonstrated a very satisfactory restoration with regard to function and esthetics as well as the stability of the mini-implant. PMID:26349292

  1. Novel treatment of equine odontoclastic tooth resorption and hypercementosis of incisor teeth in a 22-year-old Arabian mare

    PubMed Central

    Grier-Lowe, Candace K.; Anthony, James

    2015-01-01

    Equine odontoclastic tooth resorption and hypercementosis is a rarely reported condition in the incisor and canine teeth of older horses. Histologically, there is internal and external resorption of the tooth with formation of excessive cementum. Once lesions become infected or supragingival this condition is very painful. The clinical manifestation, diagnosis and treatment of hypercementosis in an Arabian mare are described. PMID:26246633

  2. Early Miocene catarrhine dietary behaviour: the influence of the Red Queen Effect on incisor shape and curvature.

    PubMed

    Deane, Andrew S

    2009-03-01

    The early Miocene catarrhine fossil record of East Africa represents a diverse and extensive adaptive radiation. It is well accepted that these taxa encompass a dietary range similar to extant hominoids, in addition to some potentially novel dietary behaviour. There have been numerous attempts to infer diet for these taxa from patterns of dental allometry and incisor and molar microwear, however, morphometric analyses until now have been restricted to the post-canine dentition. It has already been demonstrated that given the key functional role of the incisors in pre-processing food items prior to mastication, there is a positive correlation between diet and incisal curvature (Deane, A.S., Kremer, E.P., Begun, D.R., 2005. A new approach to quantifying anatomical curvatures using High Resolution Polynomial Curve Fitting (HR-PCF). Am. J. Phys. Anthropol. 128(3), 630-638.; Deane, A.S., 2007. Inferring dietary behaviour for Miocene hominoids: A high-resolution morphometric approach to incisal crown curvature. Ph.D. Dissertation. The University of Toronto.). This study seeks to re-examine existing dietary hypotheses for large-bodied early Miocene fossil catarrhines by contrasting the incisal curvature for these taxa with comparative models derived from prior studies of the correlation between extant hominoid incisor curvature and feeding behaviour. Incisor curvature was quantified for 78 fossil incisors representing seven genera, and the results confirm that early Miocene fossil catarrhines represent a dietary continuum ranging from more folivorous (i.e., Rangwapithecus) to more frugivorous (i.e., Proconsul) diets, as well as novel dietary behaviours that are potentially similar to extant ceboids (i.e., Afropithecus). Additionally, early Miocene fossil catarrhine incisors are less curved than extant hominoid incisors, indicating a general pattern of increasing mesio-distal and labial curvature through time. This pattern of morphological shifting is consistent with the Red Queen Effect (Van Valen, L., 1973. A new evolutionary law. Evol. Theory 1, 1-30), which predicts that taxa that are removed from one another by geological time, although potentially having similar diets, may exhibit differing degrees of a similar dietary adaptation (i.e., differing degrees of incisal curvature). PMID:19285590

  3. Studying Geology of Central Texas through Web-Based Virtual Field Trips

    NASA Astrophysics Data System (ADS)

    Chan, C.; Khan, S. D.; Wellner, J. S.

    2007-12-01

    Each year over 2500 students, mainly non-science majors, take introductory geology classes at the University of Houston. Optional field trips to Central Texas for these classes provide a unique learning opportunity for students to experience geologic concepts in a real world context. The field trips visit Enchanted Rock, Inks Lake, Bee Cave Road, Lion Mountain, and Slaughter Gap. Unfortunately, only around 10% of our students participate in these field trips. We are developing a web-based virtual field trip for Central Texas to provide an additional effective learning experience for students in these classes. The module for Enchanted Rock is complete and consists of linked geological maps, satellite imagery, digital elevation models, 3-D photography, digital video, and 3-D virtual reality visualizations. The ten virtual stops focus on different geologic process and are accompanied by questions and answers. To test the efficacy of the virtual field trip, we developed a quiz to measure student learning and a survey to evaluate the website. The quiz consists of 10 questions paralleling each stop and information on student attendance on the Central Texas field trip and/or the virtual field trip. From the survey, the average time spent on the website was 26 minutes, and overall the ratings of the virtual field trip were positive. Most noticeably students responded that the information on the website was relevant to their class and that the pictures, figures, and animations were essential to the website. Although high correlation coefficients between responses were expected for some questions (i.e., 0.89 for "The content or text of the website was clear" and "The information on the website was easy to read"), some correlations were less expected: 0.77 for "The number of test questions was appropriate" and "The information on the website was easy to read," and 0.70 for "The test questions reinforced the material presented on the website" and "The information on the website is relevant to my class." These virtual field trips provide an alternative for students who cannot attend the actual field trips. They also allow transfer students to experience these sites before attending upper level field trips, which often return to study these sites in more detail. These modules provide a valuable supplementary experience for all students, as they emphasize skills for which we are presently unable to provide sufficient practice in lecture, fieldtrips, or laboratory. Public access to the field trips is available at: http://geoinfo.geosc.uh.edu/VR/

  4. Assessing the ecological base flow in an experimental watershed of Central Taiwan

    NASA Astrophysics Data System (ADS)

    Wei, Chiang; Yang, Ping-Shih; Tian, Pei-Ling

    2010-05-01

    The ecological base flow is crucial for the assessment and design for habitat rehabilitation and recovery. The amount of discharge affects the aquatic creatures and may damage the existence and balance of the community under extreme low conditions. Aquatic insect is selected as the target species in this study to evaluate the influence of the discharge and to estimate the ecological base flow. The distribution of the number of species and abundance (density) versus discharge is assessed to define the critical discharge. A stream located at the alpine area in central Taiwan is selected as the study area to evaluate the base flow. From the preliminary data (Aug 2008 to May 2009) collected from Creek C of Sitou watershed (area: 1.3 km^2) shows that the abundance of several species varies with the discharge. The dominate family and genus of aquatic insects is Baetidae (Order Ephemeroptera) and Baetis spp. that accounts for 26.3 and 17.2 %, respectively. The Hilsenhoff family biotic index (FBI) shows that the water quality is classified to "Excellent" and "Good" level while the EPT Index (Index of three orders: Ephemeroptera, Plecoptera, and Trichoptera) indicates that the stream is non-polluted. The discharge of base flow interpreted from the 90%, 95% and 96% curve of duration for the daily discharge is 0.1582, 0.0476 and 0.0378 cms; the threshold value evaluated by curve of abundance vs. discharge is 0.0154 cms. Consistent observations are yet to be collected to yield more accurate results.

  5. Centralized web-based loss estimation tool: INLET for disaster response

    NASA Astrophysics Data System (ADS)

    Huyck, C. K.; Chung, H.-C.; Cho, S.; Mio, M. Z.; Ghosh, S.; Eguchi, R. T.; Mehrotra, S.

    2006-03-01

    In the years following the 1994 Northridge earthquake, many researchers in the earthquake community focused on the development of GIS-based loss estimation tools such as HAZUS. These highly customizable programs have many users, and different results after an event can be problematic. Online IMS (Internet Map Servers) offer a centralized system where data, model updates and results cascade to all users. INLET (Internet-based Loss Estimation Tool) is the first online real-time loss estimation system available to the emergency management and response community within Southern California. In the event of a significant earthquake, Perl scripts written to respond to USGS ShakeCast notifications will call INLET routines that use USGS ShakeMaps to estimate losses within minutes after an event. INLET incorporates extensive publicly available GIS databases and uses damage functions simplified from FEMA's HAZUS (R) software. INLET currently estimates building damage, transportation impacts, and casualties. The online model simulates the effects of earthquakes, in the context of the larger RESCUE project, in order to test the integration of IT in evacuation routing. The simulation tool provides a "testbed" environment for researchers to model the effect that disaster awareness and route familiarity can have on traffic congestion and evacuation time.

  6. Central Retinal Vein Occlusion: A Review of Current Evidence-based Treatment Options

    PubMed Central

    Patel, Amy; Nguyen, Christine; Lu, Stephanie

    2016-01-01

    A central retinal vein occlusion (CRVO) can induce an ischemic and hypoxic state with resulting sequelae of macular edema and neovascularization. Many treatment options have been studied. Our review aims to investigate the safety and efficacy of the multiple treatment options of CRVO. A PubMed and Cochrane literature search was performed. Well-controlled randomized clinical trials that demonstrated strong level 1 evidence-based on the rating scale developed by the British Centre for Evidence-Based Medicine were included. Seven clinical trials met inclusion criteria to be included in this review. These included studies that investigated the safety and efficacy of retinal photocoagulation (1 study), intravitreal steroid treatment (2 studies), and antivascular endothelial growth factor treatment (4 studies) for the treatment of CRVO. In addition, studies evaluating surgical treatment options for CRVO were also included. Many treatment modalities have been demonstrated to be safe and efficacious in the treatment of CRVO. These treatment options offer therapeutic benefits for patients and clinically superior visual acuity and perhaps the quality of life after suffering from a CRVO. PMID:26957838

  7. Direct pulp capping in an immature incisor using a new bioactive material.

    PubMed

    Bhat, Sham S; Hegde, Sundeep K; Adhikari, Fardin; Bhat, Vidya S

    2014-07-01

    Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future. PMID:25191081

  8. Very Large Inflammatory Odontogenic Cyst with Origin on a Single Long Time Traumatized Lower Incisor

    PubMed Central

    Freitas, Filipe; Andre, Saudade; Moreira, Andre; Carames, Joao

    2015-01-01

    One of the consequences of traumatic injuries is the chance of aseptic pulp necrosis to occur which in time may became infected and give origin to periapical pathosis. Although the apical granulomas and cysts are a common condition, there appearance as an extremely large radiolucent image is a rare finding. Differential diagnosis with other radiographic-like pathologies, such as keratocystic odontogenic tumour or unicystic ameloblastoma, is mandatory. The purpose of this paper is to report a very large radicular cyst caused by a single mandibular incisor traumatized long back, in a 60-year-old male. Medical and clinical histories were obtained, radiographic and cone beam CT examinations performed and an initial incisional biopsy was done. The final decision was to perform a surgical enucleation of a lesion, 51.4 mm in length. The enucleated tissue biopsy analysis was able to render the diagnosis as an inflammatory odontogenic cyst. A 2 year follow-up showed complete bone recovery. PMID:26393219

  9. Implant-Prosthetic Rehabilitation in Bilateral Agenesis of Maxillary Lateral Incisors with a Mini Split Crest

    PubMed Central

    Figliuzzi, M. M.; Giudice, A.; Pileggi, S.; Pacifico, D.; Marrelli, M.; Tatullo, M.; Fortunato, L.

    2016-01-01

    The reported clinical case describes the surgical procedure of ridge augmentation by using a “split crest” technique with a partial thickness flap and a subsequent implant-prosthetic rehabilitation aimed at treating a bilateral agenesis of the upper lateral incisors. In such cases with vestibule-palatal and mesial-distal scarce bone thicknesses associated with the need of a proper functional and aesthetic rehabilitation, the split crest technique is particularly suitable. In the case we reported, because of the poor bone thicknesses, we performed a minimally invasive split crest which allowed a correct insertion of the fixtures. This technique allowed us to achieve an optimal functional and aesthetic rehabilitation; moreover, we obtained a good emergency profile, ensuring the vitality of the close teeth and ensuring a good primary stability and the following osseointegration of dental implants. PMID:27190658

  10. Bilateral supplemental permanent maxillary lateral incisors in a non-syndromic patient.

    PubMed

    Bhullar, Mandeep Kaur; Uppal, Amandeep Singh; Kochhar, Gulsheen Kaur; Singh, Ranjit

    2014-01-01

    A supernumerary tooth is an additional entity to the normal series and can be seen in all quadrants of the jaw. Occurrence may be single or multiple, unilateral or bilateral, erupted or impacted in one or in both jaws. Multiple supernumeraries are rare in individuals with no other associated disease or syndromes. The conditions commonly associated with an increased prevalence of supernumerary teeth include cleft lip and palate, cleidocranial dysplasia and Gardner syndrome. The supplemental supernumerary refers to a duplication of teeth in normal series and is found at the end of a tooth series. A supplemental tooth may closely resemble the teeth of the group to which it belongs or it may bear little resemblance in size or shape to the teeth with which it is associated. This report presents a case with bilateral supplemental upper permanent lateral incisors without any symptoms of associated disorders. PMID:25168674

  11. Direct pulp capping in an immature incisor using a new bioactive material

    PubMed Central

    Bhat, Sham S.; Hegde, Sundeep K.; Adhikari, Fardin; Bhat, Vidya S.

    2014-01-01

    Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future. PMID:25191081

  12. Palatogingival Groove: Recognizing and Managing the Hidden Tract in a Maxillary Incisor: A Case Report

    PubMed Central

    Sharma, Sarang; Deepak, Passi; Vivek, Sharma; Ranjan Dutta, Shubha

    2015-01-01

    Palatogingival grooves are developmental malformations quite notorious for precipitating endodontic - periodontal lesions. Owing to their inconspicuous occurrence, funnel-shaped morphology and variable extent on tooth root, they promote adherence of plaque and bacteria to levels significant for the development of pathology. Several treatment approaches have been recognized in literature for the management of this anomaly. Here in this report, a 25-year-old patient reported with the complaint of pain and swelling in maxillary right lateral incisor. Clinical examination confirmed an endodontic - periodontal lesion in relation to palatogingival groove. Endodontic treatment was instituted, followed by odontoplasty of the groove and restoration with newer calcium silicate cement, Biodentine. Combined endodontic - periodontal approach was successful in resolving the pathology with complete healing seen both clinically and radiographically. Timely diagnosis, prevention and management are highly recommended to prevent tooth loss due to complications arising secondary to their presence. PMID:26124612

  13. Palatogingival Groove: Recognizing and Managing the Hidden Tract in a Maxillary Incisor: A Case Report.

    PubMed

    Sharma, Sarang; Deepak, Passi; Vivek, Sharma; Ranjan Dutta, Shubha

    2015-06-01

    Palatogingival grooves are developmental malformations quite notorious for precipitating endodontic - periodontal lesions. Owing to their inconspicuous occurrence, funnel-shaped morphology and variable extent on tooth root, they promote adherence of plaque and bacteria to levels significant for the development of pathology. Several treatment approaches have been recognized in literature for the management of this anomaly. Here in this report, a 25-year-old patient reported with the complaint of pain and swelling in maxillary right lateral incisor. Clinical examination confirmed an endodontic - periodontal lesion in relation to palatogingival groove. Endodontic treatment was instituted, followed by odontoplasty of the groove and restoration with newer calcium silicate cement, Biodentine. Combined endodontic - periodontal approach was successful in resolving the pathology with complete healing seen both clinically and radiographically. Timely diagnosis, prevention and management are highly recommended to prevent tooth loss due to complications arising secondary to their presence. PMID:26124612

  14. Very Large Inflammatory Odontogenic Cyst with Origin on a Single Long Time Traumatized Lower Incisor.

    PubMed

    Martins, Jorge N R; Freitas, Filipe; Andre, Saudade; Moreira, Andre; Carames, Joao

    2015-07-01

    One of the consequences of traumatic injuries is the chance of aseptic pulp necrosis to occur which in time may became infected and give origin to periapical pathosis. Although the apical granulomas and cysts are a common condition, there appearance as an extremely large radiolucent image is a rare finding. Differential diagnosis with other radiographic-like pathologies, such as keratocystic odontogenic tumour or unicystic ameloblastoma, is mandatory. The purpose of this paper is to report a very large radicular cyst caused by a single mandibular incisor traumatized long back, in a 60-year-old male. Medical and clinical histories were obtained, radiographic and cone beam CT examinations performed and an initial incisional biopsy was done. The final decision was to perform a surgical enucleation of a lesion, 51.4 mm in length. The enucleated tissue biopsy analysis was able to render the diagnosis as an inflammatory odontogenic cyst. A 2 year follow-up showed complete bone recovery. PMID:26393219

  15. The effects of spaceflight on the mineralization of rat incisor dentin

    NASA Technical Reports Server (NTRS)

    Simmons, D. J.; Rosenberg, G. D.

    1984-01-01

    Specific effects of space flight on dentin formation on the lower incisors of male rats were determined. Data were Fourier analyzed to determine the spectra of chemical growth rhythms. It was found that Calcium and P were more concentrated in the newly forming dentin of the Flight rats than in comparable regions of control tissues. There was no significant difference in the mean S-concentration between the two groups, but the pattern of S-distribution in the recently formed dentin from the Flight rats was different from that in the control group. Sulfur fluctuations in flight animals periodically peak above the irregular background fluctuations, but there are no comparable sulfur peaks across the dentin in the control. It is indicated that spaceflight has measurable effects on dentinogenesis, and may also bear on the problem of the regulatory role of proteoglycans in mineralization and the maturation of mineral and matrix moieties in skeletal tissue.

  16. Assessment of association between molar incisor hypomineralization and hypomineralized second primary molar

    PubMed Central

    Mittal, Rakesh; Chandak, Shweta; Chandwani, Manisha; Singh, Prabhat; Pimpale, Jitesh

    2016-01-01

    Background: The term molar incisor hypomineralization (MIH) has been described as a clinical entity of systemic origin affecting the enamel of one or all first permanent molars and also the incisors; less frequently the second primary molars have also been reported to develop hypomineralization of the enamel, along with MIH. Aim: To scrutinize the association between hypomineralized second primary molars (HSPMs) and MIH and their prevalence in schoolgoing pupils in Nagpur, Maharashtra, India and the associated severity of dental caries. Design: A sample of 1,109 pupils belonging to 3–12-year-old age group was included. The entire sample was then divided into Group I (3–5 years) and Group II (6–12 years). The scoring criteria proposed by the European Academy of Pediatric Dentistry for hypomineralization was used to score HSPM and MIH. The International Caries Detection and Assessment System II (ICDAS II) was used for appraising caries status in the hypomineralized molars. The examination was conducted by a single calibrated dentist in schools in daylight. The results, thus obtained, were statistically analyzed using Chi-square test and odds ratio. Result: Of the children examined, 10 in Group I (4.88%) had HSPM and 63 in Group II (7.11%) had MIH in at least one molar. In Group II, out of 63 subjects diagnosed with MIH, 30 subjects (48%) also had HSPM. Carious lesions with high severity were appreciated in hypomineralized molars. Conclusion: The prevalence of HSPM was 4.88% and of MIH was 7.11%. Approximately half of the affected first permanent molars were associated with HSPM. The likelihood of development of caries increased with the severity of hypomineralization defect. PMID:27011930

  17. Precipitation frequency analysis based on regional climate simulations in Central Alberta

    NASA Astrophysics Data System (ADS)

    Kuo, Chun-Chao; Gan, Thian Yew; Hanrahan, Janel L.

    2014-03-01

    A Regional Climate Model (RCM), MM5 (the Fifth Generation Pennsylvania State University/National Center for Atmospheric Research mesoscale model), is used to simulate summer precipitation in Central Alberta. MM5 was set up with a one-way, three-domain nested framework, with domain resolutions of 27, 9, and 3 km, respectively, and forced with ERA-Interim reanalysis data of ECMWF (European Centre for Medium-Range Weather Forecasts). The objective is to develop high resolution, grid-based Intensity-Duration-Frequency (IDF) curves based on the simulated annual maximums of precipitation (AMP) data for durations ranging from 15-min to 24-h. The performance of MM5 was assessed in terms of simulated rainfall intensity, precipitable water, and 2-m air temperature. Next, the grid-based IDF curves derived from MM5 were compared to IDF curves derived from six RCMs of the North American Regional Climate Change Assessment Program (NARCCAP) set up with 50-km grids, driven with NCEP-DOE (National Centers for Environmental Prediction-Department of Energy) Reanalysis II data, and regional IDF curves derived from observed rain gauge data (RG-IDF). The analyzed results indicate that 6-h simulated precipitable water and 2-m temperature agree well with the ERA-Interim reanalysis data. However, compared to RG-IDF curves, IDF curves based on simulated precipitation data of MM5 are overestimated especially for IDF curves of 2-year return period. In contract, IDF curves developed from NARCCAP data suffer from under-estimation and differ more from RG-IDF curves than the MM5 IDF curves. The over-estimation of IDF curves of MM5 was corrected by a quantile-based, bias correction method. By dynamically downscale the ERA-Interim and after bias correction, it is possible to develop IDF curves useful for regions with limited or no rain gauge data. This estimation process can be further extended to predict future grid-based IDF curves subjected to possible climate change impacts based on climate change projections of GCMs (general circulation models) of IPCC (Intergovernmental Panel on Climate Change).

  18. Characteristics and Composition of Atmospheric Aerosols in Phimai, Central Thailand During BASE-ASIA

    NASA Technical Reports Server (NTRS)

    Li, Can; Tsay, Si-Chee; Hsu, N. Christina; Kim, Jin Young; Howell, Steven G.; Huebert, Barry J.; Ji, Qiang; Jeong, Myeong-Jae; Wang, Sheng-Hsiang; Hansell, Richard A.; Bell, Shaun W.

    2012-01-01

    Popular summary: Atmospheric aerosols play an important role in the Earth's climate system, and can also have adverse effects on air quality and human health. The environmental impacts of aerosols, on the other hand, are highly regional, since their temporal/spatial distribution is inhomogeneous and highly depends on the regional emission sources. To better understand the effects of aerosols, intensive field experiments are necessary to characterize the chemical and physical properties on a region-by-region basis. From late February to early May in 2006, NASA/GSFC's SMARTLabs facility was deployed at a rural site in central Thailand, Southeast Asia, to conduct a field experiment dubbed BASE-ASIA (Biomass-burning Aerosols in South East-Asia: Smoke Impact Assessment). The group was joined by scientists from the University of Hawaii and other regional institutes. Comprehensive measurements were made during the experiment, including aerosol chemical composition, optical and microphysical properties, as well as surface energetics and local . meteorology. This study analyzes part of the data from the BASE-ASIA experiment. It was found that, even for the relatively remote rural site, the aerosol loading was still substantial. Besides agricultural burning in the area, industrial pollution near the Bangkok metropolitan area, about 200 km southeast of the site, and even long-range transport from China, also contribute to the area's aerosol loading. The results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow. Abstract: Comprehensive measurements of atmospheric aerosols were made in Phimai, central Thailand (15.l83 N, 102.565 E, elevation: 206 m) during the BASE-ASIA field experiment from late February to early May in 2006. The observed aerosol loading was sizable for this rural site (mean aerosol scattering: 108 +/- 64 Mm(exp -1); absorption: 15 +/- 8 Mm(exp -1); PM(sub 10) concentration: 33 +/- 17 miro-g/ cubic m and dominated by submicron particles. Major aerosol compounds included carbonaceous (OC: 9.5 +/- 3.6miro-g/ cubic m; EC: 2.0 2.3 miro-g/ cubic m and secondary species (SO4(2-): 6.4 +/- 3.7 miro-g/ cubic m, NH4(+): 2.2 +/- 1.3 miro-g/ cubic m). While the site was seldom under the direct influence of large forest fires to its north, agricultural fires were ubiquitous during the experiment, as suggested by the substantial concentration of K+ (0.56 +/- 0.33 micro-g/ cubic m). Besides biomass burning, aerosols in Phimai during the experiment were also strongly influenced by industrial and vehicular emissions from the Bangkok metropolitan region and long-range transport from southern China. High humidity played an important role in determining the aerosol composition and properties in the region. Sulfate was primarily formed via aqueous phase reactions, and hygroscopic growth could enhance the aerosol light scattering by up to 60%, at the typical morning RH level of 85%. The aerosol single scattering albedo demonstrated distinct diurnal variation, ranging from 0.86 +/- 0.04 in the evening to 0.92 +/- 0.02 in the morning. This experiment marks the first time such comprehensive characterization of aerosols was made for rural central Thailand. Our results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow.

  19. Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases

    SciTech Connect

    Thiessen, R.L.; Eliason, J.R.; Johnson, L.K.; Brougher, C.W.; Foley, M.G.; Beaver, D.E.

    1988-01-01

    The geology of the central Columbia Plateau is characterized by subdued topography and limited outcrop, with most of the exposure concentrated in localized folded/faulted mountains (the Yakima folds) and along river canyons. In order to efficiently compare lineament data bases, we have written an automated computer routine that correlates lineaments that are within a user specified distance of each other. The angle between their trends has to be less than an input maximum separation angle. If more than two lineament maps exist for the area, the analyst may also specify the minimum number of times each structure must be seen. The lineament correlation routine was applied to data bases of all aeromagnetic linears as well as lineaments seen on radar and a digital elevation model image. Due to their topographic expression and associated deformation, the Yakima folds are detected by nearly all of the studies. Other features that do not correspond to known structures are detected in a number of the above data types and so are likely to have a strong structural control. Previously mapped small faults that obliquely cross the Yakima folds were identified a multiple number of times. These structures align with a set of three-dimensional planar structures identified with our unique Geologic Spatial Analysis (GSA) system. The GSA analysis is based upon computer automated detection of valley bottoms as defined by a DEM. Valley vectors which are coplanar may be controlled by a planar geologic structure whose three-dimensional orientation can be calculated by GSA routines. 58 refs., 7 figs.

  20. Status and future transition of rapid urbanizing landscape in central Western Ghats - CA based approach

    NASA Astrophysics Data System (ADS)

    Bharath, S..; Rajan, K. S.; Ramachandra, T. V.

    2014-11-01

    The land use changes in forested landscape are highly complex and dynamic, affected by the natural, socio-economic, cultural, political and other factors. The remote sensing (RS) and geographical information system (GIS) techniques coupled with multi-criteria evaluation functions such as Markov-cellular automata (CA-Markov) model helps in analysing intensity, extent and future forecasting of human activities affecting the terrestrial biosphere. Karwar taluk of Central Western Ghats in Karnataka state, India has seen rapid transitions in its forest cover due to various anthropogenic activities, primarily driven by major industrial activities. A study based on Landsat and IRS derived data along with CA-Markov method has helped in characterizing the patterns and trends of land use changes over a period of 2004-2013, expected transitions was predicted for a set of scenarios through 2013-2022. The analysis reveals the loss of pristine forest cover from 75.51% to 67.36% (1973 to 2013) and increase in agriculture land as well as built-up area of 8.65% (2013), causing impact on local flora and fauna. The other factors driving these changes are the aggregated level of demand for land, local and regional effects of land use activities such as deforestation, improper practices in expansion of agriculture and infrastructure development, deteriorating natural resources availability. The spatio temporal models helped in visualizing on-going changes apart from prediction of likely changes. The CA-Markov based analysis provides us insights into the localized changes impacting these regions and can be useful in developing appropriate mitigation management approaches based on the modelled future impacts. This necessitates immediate measures for minimizing the future impacts.

  1. A new species of Docosia Winnertz from Central Europe, with DNA barcoding based on four gene markers (Diptera, Mycetophilidae)

    PubMed Central

    Ševčík, Jan; Kaspřák, David; Rulik, Björn

    2016-01-01

    Abstract A new species of Docosia Winnertz, Docosia dentata sp. n., is described and illustrated, based on a single male specimen collected in Muránska planina National Park in Central Slovakia. DNA sequences (COI, COII, CytB, and ITS2) are included and compared for 13 species of Docosia. There was found only little congruence between the molecular results and previous scarce data about interspecific relationships based on morphology. The COI and CytB gene markers showed the highest interspecific gene distances while ITS2 showed the lowest ones. An updated key to the 23 Central European species of Docosia is also presented. PMID:26843833

  2. A new species of Docosia Winnertz from Central Europe, with DNA barcoding based on four gene markers (Diptera, Mycetophilidae).

    PubMed

    Ševčík, Jan; Kaspřák, David; Rulik, Björn

    2016-01-01

    A new species of Docosia Winnertz, Docosia dentata sp. n., is described and illustrated, based on a single male specimen collected in Muránska planina National Park in Central Slovakia. DNA sequences (COI, COII, CytB, and ITS2) are included and compared for 13 species of Docosia. There was found only little congruence between the molecular results and previous scarce data about interspecific relationships based on morphology. The COI and CytB gene markers showed the highest interspecific gene distances while ITS2 showed the lowest ones. An updated key to the 23 Central European species of Docosia is also presented. PMID:26843833

  3. Evidence-Based Decision Making in School District Central Offices: Toward a Policy and Research Agenda

    ERIC Educational Resources Information Center

    Honig, Meredith I.; Coburn, Cynthia

    2008-01-01

    District central office administrators increasingly face policy demands to use "evidence" in their decision making. These demands up the ante on education policy researchers and policy makers to better understand what evidence use in district central offices entails and the conditions that may support it. To that end, the authors conducted a…

  4. CrisprGE: a central hub of CRISPR/Cas-based genome editing

    PubMed Central

    Kaur, Karambir; Tandon, Himani; Gupta, Amit Kumar; Kumar, Manoj

    2015-01-01

    CRISPR system is a powerful defense mechanism in bacteria and archaea to provide immunity against viruses. Recently, this process found a new application in intended targeting of the genomes. CRISPR-mediated genome editing is performed by two main components namely single guide RNA and Cas9 protein. Despite the enormous data generated in this area, there is a dearth of high throughput resource. Therefore, we have developed CrisprGE, a central hub of CRISPR/Cas-based genome editing. Presently, this database holds a total of 4680 entries of 223 unique genes from 32 model and other organisms. It encompasses information about the organism, gene, target gene sequences, genetic modification, modifications length, genome editing efficiency, cell line, assay, etc. This depository is developed using the open source LAMP (Linux Apache MYSQL PHP) server. User-friendly browsing, searching facility is integrated for easy data retrieval. It also includes useful tools like BLAST CrisprGE, BLAST NTdb and CRISPR Mapper. Considering potential utilities of CRISPR in the vast area of biology and therapeutics, we foresee this platform as an assistance to accelerate research in the burgeoning field of genome engineering. Database URL: http://crdd.osdd.net/servers/crisprge/. PMID:26120138

  5. CrisprGE: a central hub of CRISPR/Cas-based genome editing.

    PubMed

    Kaur, Karambir; Tandon, Himani; Gupta, Amit Kumar; Kumar, Manoj

    2015-01-01

    CRISPR system is a powerful defense mechanism in bacteria and archaea to provide immunity against viruses. Recently, this process found a new application in intended targeting of the genomes. CRISPR-mediated genome editing is performed by two main components namely single guide RNA and Cas9 protein. Despite the enormous data generated in this area, there is a dearth of high throughput resource. Therefore, we have developed CrisprGE, a central hub of CRISPR/Cas-based genome editing. Presently, this database holds a total of 4680 entries of 223 unique genes from 32 model and other organisms. It encompasses information about the organism, gene, target gene sequences, genetic modification, modifications length, genome editing efficiency, cell line, assay, etc. This depository is developed using the open source LAMP (Linux Apache MYSQL PHP) server. User-friendly browsing, searching facility is integrated for easy data retrieval. It also includes useful tools like BLAST CrisprGE, BLAST NTdb and CRISPR Mapper. Considering potential utilities of CRISPR in the vast area of biology and therapeutics, we foresee this platform as an assistance to accelerate research in the burgeoning field of genome engineering. PMID:26120138

  6. Coal-based stratigraphy for upper Fort Union Group (Paleocene), west-central North Dakota

    SciTech Connect

    Groenewold, G.; Hemish, L.; Daly, D.J.; Schmit, C.

    1986-08-01

    On the basis of an evaluation of lithologic and geophysical logs from 2500 shallow drill holes and information from a limited number of natural outcrops and mine highwalls, a detailed stratigraphic framework was constructed for the Paleocene strata of the Sentinel Butte and upper Bullion Creek formations (upper Fort Union Group) in the Knife River area in west-central North Dakota. The study sequence was found to be characterized by at least seven major coals continuous over the 8000 km/sup 2/ (3089 mi/sup 2/) of the study area instead of a large number of locally persistent coals, as interpreted by previous investigations of surface sections. A series of geologic cross sections demonstrates the correlation of the lignite beds in the upper Bullion Creek and Sentinel Butte formations and together provide a three-dimensional picture of coal distribution in the study area. Each major lignite bed has been named and assigned both type and reference test holes. The recognition of coals continuous over the study area provides a means of correlating this complex terrestrial section. The resulting framework in turn provides a basis for (1) the development of a chronostratigraphy and biostratigraphy, (2) a more accurate evaluation of the magnitude and distribution of coal resources, and (3) an appraisal of depositional setting and history. The recognition of widespread coals in the upper Fort Union strata in other portions of the basin suggests the potential for establishing a basinwide stratigraphic framework based on these coals.

  7. Characteristics and composition of atmospheric aerosols in Phimai, central Thailand during BASE-ASIA

    NASA Astrophysics Data System (ADS)

    Li, Can; Tsay, Si-Chee; Hsu, N. Christina; Kim, Jin Young; Howell, Steven G.; Huebert, Barry J.; Ji, Qiang; Jeong, Myeong-Jae; Wang, Sheng-Hsiang; Hansell, Richard A.; Bell, Shaun W.

    2013-10-01

    Comprehensive measurements of atmospheric aerosols were made in Phimai, central Thailand (15.183°N, 102.565°E, elevation: 206 m) during the BASE-ASIA field experiment from late February to early May in 2006. The observed aerosol loading was sizable for this rural site (mean aerosol scattering: 108 ± 64 Mm-1; absorption: 15 ± 8 Mm-1; PM10 concentration: 33 ± 17 μg m-3), and dominated by submicron particles. Major aerosol compounds included carbonaceous (OC: 9.5 ± 3.6 μg m-3; EC: 2.0 ± 2.3 μg m-3) and secondary species (SO42-: 6.4 ± 3.7 μg m-3, NH4+: 2.2 ± 1.3 μg m-3). While the site was seldom under the direct influence of large forest fires to its north, agricultural fires were ubiquitous during the experiment, as suggested by the substantial concentration of K+ (0.56 ± 0.33 μg m-3). Besides biomass burning, aerosols in Phimai during the experiment were also strongly influenced by industrial and vehicular emissions from the Bangkok metropolitan region and long-range transport from southern China. High humidity played an important role in determining the aerosol composition and properties in the region. Sulfate was primarily formed via aqueous phase reactions, and hygroscopic growth could enhance the aerosol light scattering by up to 60%, at the typical morning RH level of 85%. The aerosol single scattering albedo demonstrated distinct diurnal variation, ranging from 0.86 ± 0.04 in the evening to 0.92 ± 0.02 in the morning. This experiment marks the first time such comprehensive characterization of aerosols was made for rural central Thailand. Our results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow.

  8. A Model Based Attribution of Streamflow Trends in Headwater Catchments of the Tarim River, Central Asia

    NASA Astrophysics Data System (ADS)

    Duethmann, D.; Bolch, T.; Pieczonka, T.; Farinotti, D.; Tong, J.; Guntner, A.

    2014-12-01

    Over the last decades, increasing streamflow has been observed in glacierized headwater catchments of the Tarim River, Central Asia. We investigated to what extent these streamflow increases can be attributed to increasing precipitation, or increasing air temperature and resulting glacier mass loss, using a data-driven approach based on multiple linear regression, and a simulation-driven approach with a hydrological model. The hydrological model was calibrated in a multi-objective way using criteria for discharge and glacier mass balances. This is crucial in such catchments with high uncertainties in precipitation, as a deficient streamflow simulation due to inadequate precipitation input may be compensated by erroneous simulation of glacier melt, if both variables are not jointly considered for model calibration. Temporal variations in glacier changes were calibrated against an observed glacier mass balance time series, whilst geodetic glacier mass balance estimates were used for constraining the absolute mass balance loss. The model considers the effects of changes in glacier area and in the elevation of the glacier surface over the course of the 48-years study period. Simulations with detrended time series indicate that changes in the less glacierized Kokshaal catchment are caused by increases in precipitation and glacier melt to a comparable extent. In contrast, for the more highly glacierized Sary-Djaz catchment, increasing glacier melt plays a dominant role. Results from the data-based approach were generally comparable, but pointed to a higher influence of temperature also in the Kokshaal catchment. Overall, the hydrological modeling approach was considered as advantageous because it allows to (1) directly investigate cause-effect relations, (2) analyze the impact of changes in variables that are not measured (e.g., changes in the fraction of glacier melt), and (3) integrate different kinds of data (like glacier mass balances or snow cover data). In this way, (in-)consistencies between different hypotheses for the causes of changes, the model results and the various data can be revealed.

  9. A tunable protein-based scaffold for the study of central nervous system regeneration

    NASA Astrophysics Data System (ADS)

    Straley, Karin

    Central nervous system (CNS) injuries pose a significant and potentially debilitating health problem in society today and, to date, no successful clinical repair strategies have been advanced. The development of effective treatments is severely hindered by the quick formation of a complex, inhibitory scar at the site of CNS injury. This scar both physically blocks and chemically suppresses nerve regeneration. It has been hypothesized that combinatorial approaches involving biomaterial scaffolds, cell transplantation, and pro-survival factors, which provide a more permissive growth environment, have the highest chance of stimulating regeneration. The work completed in this thesis focuses on the design and characterization of a biomimetic hydrogel scaffold constructed from chemically crosslinked recombinant proteins. This protein-based scaffold has been designed to offer a flexible platform for the systematic optimization of key scaffold design parameters, such as mechanical strength, degradation, cellular interaction, molecule delivery, and topography. Specifically, a collection of proteins containing sequences previously shown to enhance cell adhesion, to promote neurite extension, and to exhibit varying susceptibility to cleavage by neurite-secreted proteases were synthesized to serve as the polymer backbone for the scaffold. Experiments were conducted to analyze the capacity of scaffolds, constructed from single proteins or mixtures of proteins, to independently control cell behavior, scaffold degradation properties, and scaffold mechanical properties based upon differences in the primary protein sequence and crosslinking conditions. In addition, composite scaffolds constructed by layered spatial deposition of chemically crosslinked, protease-degradable proteins were applied to the formation of dynamic internal, three-dimensional scaffold patterns that can be directly coupled to molecule delivery. Overall, this work demonstrates the tunable and bio-functional nature of these hydrogels and sets the framework for future studies into the development of effective protein-engineered scaffolds for CNS regeneration.

  10. A river based stable isotope record of orographic precipitation: Taurus Mountains, south central Turkey

    NASA Astrophysics Data System (ADS)

    Schemmel, Fabian; Mulch, Andreas; Mikes, Tamás.; Schildgen, Taylor

    2010-05-01

    Reconstructing continental precipitation and vegetation patterns has become one of the most rapidly growing fields in terrestrial paleoclimate research. Furthermore, stable isotopes in precipitation within continental plateau regions represent an increasingly important tool for reconstructing the various effects of uplift related climate change within the world's largest plateau regions. With peak elevations of more than 3,000 m the Taurus Mountains represent the southern margin of the central Anatolian plateau and must have played a pivotal role in controlling the drainage and sedimentation patterns within the plateau interior. However, their surface uplift history remains largely elusive. We sampled a series of tributaries and rivers along the Ermenek valley that crosscuts the Taurus Mountains in Southern Turkey. The aim of this study is to quantify the modern effect of orographic rainout of the Taurus Mountains on the d18O and dD values of river and spring waters and to compare these values to the d18O and dD of recent precipitation gathered by the Global Network of Isotopes in Precipitation (GNIP). Further we try to study the trends of the recent d18O and dD isotopic composition of local rivers and precipitation in the area to create a set of isotopic data that is comparable to isotopic studies on paleosoils and can therefore be used in future paleoaltimetry and paleoclimate studies. We sampled 6 individual rivers during the fall season 2008 to capture mostly groundwater runoff in the south central Taurus Mountains. All sampled rivers belong to the same local drainage system which drains into the Mediterranean Sea. The total elevation difference within the sampling area exceeds 2,000 m and we were able to collect samples over almost 1,800 m of elevation. Our measurements show that both d18O and dD values follow the same basic trend. d18O and dD values decrease systematically with increasing elevation. The lapse rate of d18O is about -2.2 per mil/km, whereas the lapse rate of dD is about -20 per mil/km. Select samples have higher d18O and dD values than expected for their respective elevations due to strong evaporative effects at the sampling sites. In areas of very steep topography (waterfalls, valley gorges) the d18O and dD values of water samples are biased towards values lower than expected for their respective elevations. However, such irregularities can be accounted for by plotting the measured isotopic compositions against the hypsometric mean elevations instead of the actual sampling elevations. Comparison with data gathered by the GNIP network at four neighboring stations (Adana, Antalya, Güzeloluk, and Kocebeyli) shows that the longer-term (1 to 18 years) isotopic composition of precipitation agrees very well with the data collected in this study. Collectively, the data presented here may serve as a modern template against which late Neogene proxy-based records of paleoprecipitation along the southern margin of the central Anatolian plateau may be calibrated.

  11. Basement structure based on gravity anomaly in the northern Noto peninsula, Central Japan

    NASA Astrophysics Data System (ADS)

    Mizubayashi, T.; Sawada, A.; Hamada, M.; Hiramatsu, Y.; Honda, R.

    2012-12-01

    Upper crustal block structures are usually defined by using surface information, such as geological and morphological data. The northern Noto Peninsula, central Japan, is divided into four geological block structures from tectonic geomorphologic perspectives (Ota and Hirakawa, 1979). This division is based on the surface crustal movement. To image the geological blocks three-dimensionally, it is necessary to construct a subsurface structure model. Gravity survey can clarify the detailed subsurface structure with dense gravity measurement. From the detailed Bouguer anomalies in the northwestern Noto Peninsula, Honda et al. (2008) suggested that the rupture size of the 2007 Noto Hanto earthquake was constrained by the geological block structures. Hiramatsu et al. (2008) also suggested the active faults on the seafloor, such as the source fault of the 2007 Noto Hanto earthquake plays a major role for the formation of the geological block structures. In this study, we analyze subsurface density structure based on the Bouguer anomaly and estimate the distribution of basement depth in the northern Noto Peninsula. We focus the relationship among the basement depth, the block structures and the active faults on the seafloor and discuss the block movement in the northern Noto Peninsula. We compiled the data measured and published previously (Gravity Database of Southwest Japan, 2001; Geological survey of Japan, 2004; Geographical survey institute of Japan, 2006; The Gravity Research Group in Southwest Japan, 2001; Komazawa and Okuma, 2010; Hokuriku electric power Co. Ltd., undisclosed) and calculated Bouguer anomaly in the northern Noto Peninsula. Based on this Bouguer anomaly, we analyzed subsurface density structures along 13 northeastern-southwestern profiles and 35 northwestern-southeastern profiles with the interval of 2 km using the two dimensional Talwani's method (Talwani et al., 1959). In the analysis, we assumed a density structure with four layers: basement (density is 2670kg/m3), Neocene volcanic rock (density is 2400kg/m3, or 2550kg/m3), Neocene sedimentary rock (density is 2200kg/m3), and Quaternary sedimentary rock (density is 1800kg/m3, or 1500kg/m3) (Honda et al., 2008). To compare our basement model to the geological block structures, we focus on a transition zone of the basement depth. We recognize that two of three geological block boundaries correspond to the transition zones. These boundaries also correspond to the boundary of active fault segments on the seafloor. Therefore, based on the relationship between the source fault of the 2007 Noto Hanto earthquake and the geological block, we suggest that the movement of those geological blocks is possibly controlled by the corresponding active fault segments. However, we find that the other block boundary doesn't correspond to the transition zone.

  12. An EO-Based Approach to Modelling Ecosystem Health in Response to Wildfire in Central Greece

    NASA Astrophysics Data System (ADS)

    Evans, Aaron; Petropoulos, George P.

    2014-05-01

    Assessment of ecosystem health is becoming more relevant in a world where ecosystems are being used unsustainably and have been showing increased signs of stress and dysfunction. Therefore, this research has set out to establish an Earth Observation (EO) based methodology in conjunction with Geographical Information Systems (GIS) to establish and monitor the indicators of ecosystem health in a region affected by wildfire in Central Greece. A further goal has been to assess the responses of ecosystem health to wildfire and urban expansion in the studied region. The methodology integrated GIS software and EO data to assess ecosystem characteristics including: vigour, organisation and resilience. The characteristics were quantified using remote sensing techniques focusing on Normalised Difference Vegetation Index (NDVI) images derived from Landsat imagery from 1999-2011. Topographic features including slope and aspect were extracted from a digital elevation model (DEM). These elements were then assigned weightings based upon research and combined in a model to produce a map of ecosystem health. The map of ecosystem health was validated against a compound topographic index that was produced for the study region, completed by overlaying the layers in Google Earth. This software allowed for a direct comparison of each layer. The results of the model have demonstrated correlations with past wildfires and the associated recovery. The findings are in agreement with the hypothesis that ecosystem health maps can illustrate the effect wildfires have on ecosystem health, thus providing useful information to land managers and policy makers who manage wildfire. The results further demonstrate that the resolution of Landsat imagery is excellent for obtaining a general overview of ecosystem health mapping. The methods described in this study could provide more detailed information if applied to high resolution imagery such as Worldview or IKONOS data. Results could be further enhanced with hyperspectral sensors due to the possibility of detecting chemical processes associated with ecosystem process. The method is robust enough to be transferable to other regions, with some minor changes based on a specified climate for a given location. The launch of Landsat 8 will ensure the continued acquisition and availability of Landsat data as well as provide high quality images, also making it possible to develop this method to potentially contribute to an operational estimation of ecosystem health recovery after wildfire.

  13. A Rare Case of Bilateral Agenesis of Central Lower Incisors Associated With Upper Impacted Canine- A Case Report

    PubMed Central

    PORUMB, Anca; IGNAT ROMANUL, Ioana; DALAI, Camelia; CIAVOI, Gabiela; TIG, Ioan Andrei

    2016-01-01

    This case of a female patient, 14 yr old with association of the two anomalies, which we came across with in 2014, is rarely met in the specialty practice. The impacted canines are part of the group of dental anomalies of position, while the agenesis is part of the group of dental number anomalies. The orthodontic treatment in the two arches has to be differentiated, the therapeutic objectives being, also different in the two arches.

  14. A Rare Case of Bilateral Agenesis of Central Lower Incisors Associated With Upper Impacted Canine- A Case Report.

    PubMed

    Porumb, Anca; Ignat Romanul, Ioana; Dalai, Camelia; Ciavoi, Gabiela; Tig, Ioan Andrei

    2016-03-01

    This case of a female patient, 14 yr old with association of the two anomalies, which we came across with in 2014, is rarely met in the specialty practice. The impacted canines are part of the group of dental anomalies of position, while the agenesis is part of the group of dental number anomalies. The orthodontic treatment in the two arches has to be differentiated, the therapeutic objectives being, also different in the two arches. PMID:27141502

  15. Autotransplantation combined with orthodontic treatment: a case involving the maxillary central incisors with root resorption after traumatic injury

    PubMed Central

    Ferreira, Hugo M.; Botelho, Filomena; Carrilho, Eunice

    2015-01-01

    Traumatic dental injury can result in avulsion of anterior teeth. In young patients, it is a challenge to the dental professional because after replantation, late complications such as ankylosis require tooth extraction. Although prosthetic and orthodontic treatment, and implant placement have been described as the options for intervention, autogenous tooth transplantation could be an effective procedure in growing patients if there is a suitable donor tooth available. This case presents the treatment of a patient who suffered a traumatic injury at 9 years old with avulsion of tooth 21, which had been replanted, and intrusion of tooth 11. Both teeth ankylosed; thus they were removed and autotransplantation of premolars was carried out. After transplantation, the tooth underwent root canal treatment because of pulpal necrosis. Orthodontic treatment began 3 months after transplantation and during 7 years' follow-up the aesthetics and function were maintained without signs of resorption. PMID:26295028

  16. Retrieval of Iatrogenically Pushed Pulp Stone From Middle Third of Root Canal in Permanent Maxillary Central Incisor: A Case Report

    PubMed Central

    Juneja, Suruchi; Randhawa, Sohajpreet; Dhebar, Tejal Malay; Raheja, Anupama

    2015-01-01

    The pulp stones are the discrete nodular calcified masses commonly existing in coronal and occasionally in radicular pulp, placed freely, attached or embedded into the dentine. The present case report revealed the iatrogenic pushing of pulp stone and blockage of root canal that caused endodontic failure. The case enlightens the proper use of ultrasonic instruments with irrigating solutions to manage the calcifications in root canal for successful endodontic therapy. PMID:26266224

  17. Double talon cusps on supernumerary tooth fused to maxillary central incisor: Review of literature and report of case

    PubMed Central

    2014-01-01

    Human tooth development is a continuous process begin at the sixth weeks in utero and extends to about sixth months after birth for the primary dentition and from sixteenth week in utero to late adolescence for permanent dentition. There is no other organ of the human body which takes so long to attain its ultimate morphology as dentition. Several physiologic growth processes participate in the progressive development of the teeth including: initiation, proliferation, histodifferentiation, morphodifferentiation, apposition, calcification, and eruption. Aberrations in different stages of tooth development can result in unique manifestations both in primary and permanent dentitions. The fact that premaxilla is the predilection site for the occurrence of supernumerary teeth, talon cusp, dens invaginatus, and geminated teeth may suggest that the embryological development of premaxilla differ from other sites of the jaws. The dental abnormalities presented in this review are of great concern to dentist and parents because they create clinical, pathological and esthetic problems. Dental practitioner should be aware of the clinical sign, associated problems and treatment options for a given case. Key words:Double talon cusps, fusion, supernumerary, case report. PMID:25593664

  18. A BiomeBGC-based Evaluation of Dryness Stress of Central European Forests

    NASA Astrophysics Data System (ADS)

    Buddenbaum, H.; Hientgen, J.; Dotzler, S.; Werner, W.; Hill, J.

    2015-04-01

    Dryness stress is expected to become a more common problem in central European forests due to the predicted regional climate change. Forest management has to adapt to climate change in time and think ahead several decades in decisions on which tree species to plant at which locations. The summer of 2003 was the most severe dryness event in recent time, but more periods like this are expected. Since forests on different sites react quite differently to drought conditions, we used the process-based growth model BiomeBGC and climate time series from sites all over Germany to simulate the reaction of deciduous and coniferous tree stands in different characteristics of drought stress. Times with exceptionally high values of water vapour pressure deficit coincided with negative modelled values of net primary production (NPP). In addition, in these warmest periods the usually positive relationship between temperature and NPP was inversed, i.e., under stress conditions, more sunlight does not lead to more photosynthesis but to stomatal closure and reduced productivity. Thus we took negative NPP as an indicator for drought stress. In most regions, 2003 was the year with the most intense stress, but the results were quite variable regionally. We used the Modis MOD17 gross and net primary production product time series and MOD12 land cover classification to validate the spatial patterns observed in the model runs and found good agreement between modelled and observed behaviour. Thus, BiomeBGC simulations with realistic site parameterization and climate data in combination with species- and variety-specific ecophysiological constants can be used to assist in decisions on which trees to plant on a given site.

  19. Disease burden of enterovirus 71 in rural central China: A community-based survey.

    PubMed

    Gan, Zheng-kai; Jin, Hui; Li, Jing-xin; Yao, Xue-jun; Zhou, Yang; Zhang, Xue-feng; Zhu, Feng-cai

    2015-01-01

    In recent years, the epidemics of hand, foot, and mouth disease (HFMD) centered in the Asian-Pacific region have been characterized by high morbidity and mortality. Enterovirus 71 (EV71) infections were responsible for the majority of the infections leading to severe cases of HFMD and death. This is a community-based survey aimed to estimate the disease burden of EV71 in rural central China, especially for HFMD. From 2011 to 2013, demographic and socio-economic data were gathered from 343 ill children and their parents using a structured questionnaire. We quantified the health burden of disease resulting from EV71 infection in disability-adjusted life years (DALYs). Among 343 cases, 303 had confirmed HFMD, 6 presented with herpangina, 25 presented with respiratory symptoms, and 9 presented with non-specific symptoms. The number of severe cases was 47 (including 1 death) and all of these presented with HFMD. The total cost per patient for severe HFMD, mild HFMD, herpangina, respiratory disease, and non-specific disease was $2149.47, $513.22, $53.28, $31.95, and $39.25, respectively. The overall cost of EV71-related diseases as a proportion of local farmers' per capita net income ranged from 0.18% for those with non-specific disease to 187.12% for those with severe HFMD. The loss of DALYs for the 5 forms of disease were 3.47, 1.76, 1.07, 1.44, 1.22 person-years per 1000 persons, respectively. This study provides data on cost of treatment and health burden for diseases caused by EV71, which can be used in the evaluation of EV71 vaccine cost-effectiveness. PMID:26158689

  20. Remote Sensing Based Biophysical Characterization of Tropical Deciduous Forest in Central India

    NASA Astrophysics Data System (ADS)

    Singh, R. P.; Goroshi, S.; Sharma, N. K.; Bairagi, G. D.; Sharma, R.; Jalil, P.; Jain, A.; Sonakia, A.; Parihar, J. S.

    2011-09-01

    The paper reports the measurements of biophysical parameters using field and satellite data over a tropical deciduous forest Kanha National Park (KNP), central India. Field measurement (GBH, LAI, litter, soil moisture) was carried out over ten quadrates of 0.1ha in KNP for characterization of biophysical parameters with specified measurement protocol and sampling. Satellite based remote sensing analysis (LAI, Phenology, and NPP) was carried out using multi date observations of IRS-LISS-III, IMS-1MX, SPOT-VEGETATION and EOS-MODIS instruments. Rank correlation analysis using field data collected in the selected quadrates at KNP showed Sal (Shorea robusta) is dominant forest species followed by Lendia, Jamun (Syzygium cumini), Saja, Harra and Dhawda etc. Field measurement of Sal showed GBH range from 20 cm to 170 cm. Different forest classes such as Sal; Sal mixed with Jamun, Bamboo (Dendrocalamus strictus) etc, including grasslands/scrubland were classified with overall accuracy of 85.56 percent using March, May and October multi spectral data. Sal has distinct growth characteristics (low vegetation growth/ leaf fall in March instead of May) as compared to other vegetation species. As per the Leaf Area Index (LAI) measurement using hemispherical photographs, Sal showed the highest LAI (6.95 m2/m2) during September and lowest LAI (2.63 m2/m2) during March. Overall good agreement (r= 0.79) was found between the LAI generated from LISS-III and MODIS data product. It was observed from SPOT-VEGETATION analysis that NPP varied from 8.4 tC/ha/year (dry deciduous forest) to 14.25 tC/ha/year (Moist deciduous forest) in KNP.

  1. Halogens in water from the crystalline basement of the Gotthard rail base tunnel (central Alps)

    NASA Astrophysics Data System (ADS)

    Seelig, Ulrike; Bucher, Kurt

    2010-05-01

    Drilling of the new Gotthard rail base tunnel (central Alps) opened a large number of water-conducting fractures in granite and gneiss of the crystalline basement. The overburden reaches locally more than 2000 m and water and rock temperature is up to 45 °C. The tunnel crosses a series of steeply dipping fractured rock units that also crop out at the surface above the tunnel. Recharge water enters the fractured rocks in the high mountainous area, migrates gravity driven to the sampling locality in the tunnel. Along its flow path it reacts with rocks exposed on the fractures where it dissolves the principal granite minerals, resulting in high-pH Na 2CO 3 waters. The tunnel waters contain unusually high concentrations of fluoride ranging from 5 to 29 mg/L. Alteration of F-bearing biotite to F-free chlorite is one of the sources of fluorine. The highest F-concentrations result from the equilibration of low-Ca waters with fluorite. Fluoride concentration is strongly lithology-dependent and sharp discontinuities in both, concentration and saturation state with respect to fluorite occur at the contacts of the different gneiss and granite slabs. Chloride concentrations vary between 1 and 1300 mg/L. In contrast, the Cl/Br mass ratio exhibits small variations and centers around 110 suggesting a common source for the Cl and Br, which is independent of the lithology. In the northern part of the tunnel, Cl and Br are chiefly derived from saline pore fluids of one lithology which is then mixed with low-salinity water along flow paths. Cl/Br ratios of the waters in the southern part of the tunnel section are similar to those measured in experimental leachates from different tunnel rocks, suggesting that leaching of metamorphic fluids in the pore space is the main source of both Cl and Br.

  2. Attenuation Tomography Based on Strong Motion Data: Case Study of Central Honshu Region, Japan

    NASA Astrophysics Data System (ADS)

    Kumar, Parveen; Joshi, A.; Verma, O. P.

    2013-12-01

    Three-dimensional frequency dependent S-wave quality factor (Qβ(f)) value for the central Honshu region of Japan has been determined in this paper using an algorithm based on inversion of strong motion data. The method of inversion for determination of three-dimensional attenuation coefficients is proposed by H ashida and S himazaki (J Phys Earth. 32, 299-316, 1984) and has been used and modified by J oshi (Curr Sci. 90, 581-585, 2006; Nat Hazards. 43, 129-146, 2007) and J oshi et al. (J. Seismol. 14, 247-272, 2010). Twenty-one earthquakes digitally recorded on strong motion stations of Kik-net network have been used in this work. The magnitude of these earthquake ranges from 3.1 to 4.2 and depth ranging from 5 to 20 km, respectively. The borehole data having high signal to noise ratio and minimum site effect is used in the present work. The attenuation structure is determined by dividing the entire area into twenty-five three-dimensional blocks of uniform thickness having different frequency-dependent shear wave quality factor. Shear wave quality factor values have been determined at frequencies of 2.5, 7.0 and 10 Hz from record in a rectangular grid defined by 35.4°N to 36.4°N and 137.2°E to 138.2°E. The obtained attenuation structure is compared with the available geological features in the region and comparison shows that the obtained structure is capable of resolving important tectonic features present in the area. The proposed attenuation structure is compared with the probabilistic seismic hazard map of the region and shows that it bears some remarkable similarity in the patterns seen in seismic hazard map.

  3. Radicular cyst arising from a traumatized primary incisor: a case report of a rare complication that emphasizes the need for regular follow up.

    PubMed

    Smith, Alastair T F; Cowpe, Jonathan G

    2005-03-01

    Radicular cysts associated with the deciduous dentition are rare. The literature is sparse regarding cysts associated with primary incisor teeth, which is surprising given the frequency with which these teeth are traumatized. Most cases reported involve molar teeth associated with apical infection following on from caries. A case of a 3-year-old boy who developed a large radicular cyst associated with a previously traumatized upper primary incisor is reported. PMID:15819155

  4. [Blood vessels of the periodontium of incisors and molars of the lower jaw of the white rat].

    PubMed

    Varshavskiĭ, A I

    1985-12-01

    By means of injective and noninjective methods, the structural organization of the incisor and molar blood bed has been studied in the white rat mandible. For the periodontal blood bed, distinguishing by a pronounced organo-specificity, distribution of arterial and venous vessels between collagenous fiber bundles and a reticular arrangement of the capillaries is peculiar. A definite connection is clearly seen between angioarchitectonics of different segments of the periodontium, its structure and function. Unequal density of the capillary networks in the area of the epithelial dental organ and difference of the periodontal angioarchitectonics with the lingual and labial surfaces of the incisors are noted. The area of the epithelial dental organ, having a peculiar functional importance, is characterized by multiple pathways of blood inflow and outflow, by concentration of structural-functional adaptations which increase expansiveness, capacity and diffusive surface of metabolic microvessels, by a small critical thickness of the tissue layer between neighbouring capillaries. PMID:4091685

  5. Deep sounding TEM investigation method based on a modified fixed central-loop system

    NASA Astrophysics Data System (ADS)

    Xue, Guo-qiang; Bai, Chao-ying; Yan, Shu; Greenhalgh, Stewart; Li, Mei-fang; Zhou, Nan-nan

    2012-01-01

    The central-loop TEM technology has been widely used in mineral exploration, engineering and environmental investigations and assorted geologic studies. For easy and efficient working conditions, a square (or rectangular) loop is generally employed instead of a circular one. Any position within the inner one ninth of the central part of the loop is often designated as the central survey location (within which the field is assumed to be uniform), and referred to as a modified central-loop configuration. However, the deduced field parameters at such non-central positions when calculated by a central-loop formula result in decreased accuracy and possibly erroneous interpretation. A large-fixed loop offers the advantage of being able to determine the induced potential at any point inside or outside the loop. In this study we provide the formula for the large-fixed loop and receiver positions within the modified central-loop system and solve the problem. Specifically, we compute the electromagnetic response of any field point by using an electric dipole integration method. The full time-domain apparent resistivity values are then extracted by using an iterative method. Both theoretical modeling and real data examples indicate that such a configuration not only improves the accuracy for the TEM survey, but also enlarges the exploration depth, due to a large loop used in the deployment. The method is used for locating the water enriched areas in coal mines in Yangquan region of Shanxi province and in Bin County of Shaanxi province, China. The interpreted results are tested by later drilling, which confirmed our combined method to be a reliable and efficient method for deep sounding.

  6. Unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor: a report of a rare case.

    PubMed

    Cunha, Rodrigo Sanches; Junaid, Alanna; Mello, Isabel

    2015-03-01

    A supernumerary tooth is an additional entity to the normal series of teeth that may occur in isolation or may be fused to a normal counterpart. Diagnosis and delineation of an accurate treatment plan in cases involving supernumerary teeth are often a challenge. This report describes a case of unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor in which a conservative approach was used to reach a favorable outcome. PMID:25498832

  7. Replacement of missing lateral incisors with lithium disilicate glass-ceramic veneer-fixed dental prostheses: a clinical report

    PubMed Central

    Bissasu, Sami M; Al-houri, Nabil A

    2014-01-01

    Key Clinical Message This report describes the use of lithium disilicate glass-ceramic veneer-fixed dental prostheses in replacing congenitally missing maxillary lateral incisors. This kind of prosthesis has an advantage over a lingual-retainer resin-bonded fixed dental prosthesis in its capability of changing the color and shape of the abutment teeth. The prostheses provided an acceptable esthetics and comfort for the patient. PMID:25356269

  8. Direct evidence of central European forest refugia during the last glacial period based on mollusc fossils

    NASA Astrophysics Data System (ADS)

    Juřičková, Lucie; Horáčková, Jitka; Ložek, Vojen

    2014-07-01

    Although there is evidence from molecular studies for the existence of central European last glacial refugia for temperate species, there is still a great lack of direct fossil records to confirm this theory. Here we bring such evidence in the form of fossil shells from twenty strictly forest land snail species, which were recorded in radiocarbon-dated late glacial or older mollusc assemblages of nine non-interrupted mollusc successions situated in the Western Carpathians, and one in the Bohemian Massif. We proposed that molluscs survived the last glacial period in central Europe in isolated small patches of broadleaf forest, which we unequivocally demonstrate for two sites of last glacial maximum age.

  9. Zirconia crowns for rehabilitation of decayed primary incisors: an esthetic alternative.

    PubMed

    Ashima, G; Sarabjot, K Bhatia; Gauba, K; Mittal, H C

    2014-01-01

    Esthetic management of extensively decayed primary maxillary anterior teeth requiring full coronal coverage restoration is usually challenging to the pediatric dentists especially in very young children. Many esthetic options have been tried over the years each having its own advantages, disadvantages and associated technical, functional or esthetic limitations. Zirconia crowns have provided a treatment alternative to address the esthetic concerns and ease of placement of extra-coronal restorations on primary anterior teeth. The present article presents a case where grossly decayed maxillary primary incisors were restored esthetically and functionally with ready made zirconia crowns (ZIRKIZ, HASS Corp; Korea). After endodontic treatment the decayed teeth were restored with zirconia crowns. Over a 30 months period, the crowns have demonstrated good retention and esthetic results. Dealing with esthetic needs in children with extensive loss of tooth structure, using Zirconia crowns would be practical and successful. The treatment described is simple and effective and represents a promising alternative for rehabilitation of decayed primary teeth. PMID:25631720

  10. The application of fiber core posts in restoring badly destroyed primary incisors.

    PubMed

    Sharaf, Aly A

    2002-01-01

    Early childhood caries (ECC) represents a challenge to pediatric dentists especially, when teeth are badly destroyed. ECC involves the upper anterior teeth early in life and by the time the dentist sees the child, most of the coronal structure is lost. Dentally, this is a very devastating situation for both the dentist and parents, as in many cases, extraction of these teeth is the only option. With the introduction of new adhesive systems and restorative materials, a new approach for treating these teeth is explained and documented by clinical cases, where fiber core posts are introduced into the root canals of primary incisors for a distance of 2 to 3 mm. It is retained in place by flowable composite, then the coronal part is reconstructed by a strip crown to restore the crown form. After a follow up period of one year, only 2 teeth out of 30 had to be extracted. The failure was attributed to failure in pulpal therapy rather than failure in the restorations, which were totally intact. A laboratory testing of the fracture load resistance of the restored teeth proved that this technique significantly improved the fracture load resistance of composite celluloid crowns, making it a valuable procedure to consider when the coronal tooth structure is not enough to support and retain a composite celluloid strip crown. PMID:11990042

  11. Relapse of incisor crowding: A visit to the prince of salina

    PubMed Central

    Gandía, Jose L.

    2013-01-01

    The management of the retention period after comprehensive orthodontic treatment is of great importance, as a primary goal of clinician. Considerable controversy still surrounds the problem of stability after the retention period. Many studies analyze factors associated to the presence of crowding or incisor irregularity and find predictive features on its relapse. Most studies have reported little o no correlation between the treatment changes in the biological parameters - clinical, biometric (irregularity index, intermolar width, intercanine width, arch length, overjet, overbite), or cephalometric variables- that ocurred and the posttretament and postretention changes that may predict their future development. This article provides a bibliographical overview on the relapse of dental alignment in treated cases. In a brief historical introduction, the first studies on the long-term stability of orthodontic results are analysed. The article then goes on to assess studies that focus attention on anteroinferior alignment before finally studying relapse of upper crowding. It concludes by making some final comments in the light of the bibliography provided and the differents schools regarding retention needs and methods. Key words:Retention, stability, irregularity, dental alignment. PMID:23229267

  12. Computer-assisted intraosseous anaesthesia for molar and incisor hypomineralisation teeth. A preliminary study.

    PubMed

    Cabasse, C; Marie-Cousin, A; Huet, A; Sixou, J L

    2015-03-01

    Anesthetizing MIH (Molar and Incisor Hypomineralisation) teeth is one of the major challenges in paediatric dentistry. Computer-assisted IO injection (CAIO) of 4% articaine with 1:200,000 epinephrine (Alphacaine, Septodont) has been shown to be an efficient way to anesthetize teeth in children. The aim of this study was to assess the efficacy of this method with MIH teeth. This preliminary study was performed using the Quick Sleeper system (Dental Hi Tec, Cholet, France) that allows computer-controlled rotation of the needle to penetrate the bone and computer-controlled injection of the anaesthetic solution. Patients (39) of the department of Paediatric Dentistry were included allowing 46 sessions (including 32 mandibular first permanent molars) to be assessed. CAIO showed efficacy in 93.5% (43/46) of cases. Failures (3) were due to impossibility to reach the spongy bone (1) and to achieve anaesthesia (2). This prospective study confirms that CAIO anaesthesia is a promising method to anesthetize teeth with MIH that could therefore be routinely used by trained practitioners. PMID:26058304

  13. Geodiversity of the Umbria region (central Italy): a GIS-based quantitative index

    NASA Astrophysics Data System (ADS)

    Melelli, Laura; Pica, Alessia; Del Monte, Maurizio

    2014-05-01

    The measure of natural range related to geological bedrock, landforms and geomorphological processes is the necessary starting point to geodiversity evaluation. Geodiversity plays a strategic role in landscape management. Whereas geotourism and geosites are identified as a driving power for the scientific and economic promotion of an area, the geodiversity knowledge is required for a complete and accurate research. For example, high values of this abiotic parameter identify and support the foundation of geoparks. According to this perspective, the geodiversity is the unifying factor for these areas of interest. While a subjective and qualitative approach may be adequate for geosites definition, identification and cultural promotion, the geodiversity concept needs a different evaluation method. A quantitative procedure allows achieving an objective and repeatable process exportable in different geographic units. Geographical Information Systems and spatial analysis techniques are the base to quantitative evaluation involving topographic, geological and geomorphological data. Therefore, the assessment of a numerical index derived from the overlay of spatial parameters can be conveniently computed in GIS environment. In this study, a geodiversity index is proposed where geological, geomorphological and landcover factors deriving mainly from maps and field survey; topographic ones are employed from DEM and remote sensed data. Each abiotic parameter is modelled in a grid format; focal functions do provide neighbourhood analysis and computing variety statistics. A particular extent is dedicated to topographic information and terrain roughness, that are strictly related to efficiency of geomorphological processes and generally corresponding to the abiotic components variability. The study area is located in central Italy and is characterized by a well known natural heritage. Thirty-seven geosites are detected in the Umbria region, where seven regional and one natural parks are present. All the area shows a strong correlation between the geological setting and the relief energy associated to topography assessment. Three main outcrop complexes are present: a fluvial lacustrine, where the lowest slope values and plain area are widespread; a terrigenous one, with a medium slope value; and a calcareous complex corresponding to the mountain areas and the highest amplitude of relief. This partition matches different geomorphological processes and landforms, ensuring a widespread distribution of geodiversity. The final map is a digital data that localizes areas with, respectively, null or minimum, medium, and high geodiversity values. The highest class overlaps to geosites areas, to high values of amplitude of relief and where the geomorphological processes are more effective and various. This confirms the method accuracy. The results obtained represent an important advancement in geodiversity research and a significant instrument for economic development and conservation management.

  14. Estimation of Evapotranspiration of Almond orchards using Remote Sensing based SEBAL model in Central Valley, California

    NASA Astrophysics Data System (ADS)

    Roy, S.; Ustin, S.; Kefauver, S. C.

    2009-12-01

    Evapotranspiration is one of the main components of the hydrologic cycle and its impact to hydrology, agriculture,forestry and environmental studies is very crucial. SEBAL (Surface Energy Balance Algorithm for Land) is an image-processing model comprised of twenty-five computational sub-models that computes actual evapotranspiration (ETa) and other energy exchanges as a component of energy balance which is used to derive the surface radiation balance equation for the net surface radiation flux (Rn) on a pixel-by-pixel basis. For this study, SEBAL method is applied to Level 1B dataset of visible, near-infrared and thermal infrared radiation channels of MASTER instrument on-board NASA-DC 8 flight. This paper uses the SEBAL method to (1) investigate the spatial distribution property of land surface temperature (Ls), NDVI, and ETa over the San Joaquin valley. (2) Estimate actual evapotranspiration of almond class on pixel-by-pixel basis in the Central valley, California. (3) Comparison of actual Evapotranspiration obtained from SEBAL model with reference evapotranspiration (Eto) using Penman Monteiths method based on the procedures and available data from California Irrigation Management Information System (CIMIS) stations. The results of the regression between extracted land surface temperature, NDVI and, evapotranspiration show negative (-) correlation. On the other hand Ls possessed a slightly stronger negative correlation with the ETa than with NDVI for Almond class. The correlation coefficient of actual ETa estimates from remote sensing with Reference ETo from Penmann Monteith are 0.8571. ETa estimated for almond crop from SEBAL were found to be almost same with the CIMIS_Penman Monteith method with bias of 0.77 mm and mean percentage difference is 0.10%. These results indicate that combination of MASTER data with surface meteorological data could provide an efficient tool for the estimation of regional actual ET used for water resources and irrigation scheduling and management. Keywords: Evapotranspiration, Hydrologic cycle, SEBAL, net surface radiation flux, MASTER, NDVI, Penman Monteith, CIMIS, Surface Temperature

  15. Isotopic constraints on the genesis of base-metal ores in southern and central Sardinia

    USGS Publications Warehouse

    Ludwig, K. R.; Vollmer, R.; Turi, B.; Simmons, K.R.; Perna, G.

    1989-01-01

    The Pb-Zn-Ag deposits of southwestern and central Sardinia occur within a restricted region, but comprise a variety of mineralization ages and styles. New Pb-isotope data, together with published data provide a reasonably coherent picture of possible sources for the various types of deposits. -from Authors

  16. Sensor-based mapping of soil quality on degraded claypan landscapes of the central United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Claypan soils (Epiaqualfs) in the central USA have experienced severe erosion as a result of tillage practices of the late 1800s and 1900s. Because of the site-specific nature of erosion processes within claypan fields, research is needed to achieve cost-effective sensing and mapping of soil and lan...

  17. Sexual Precocity--Genetic Bases of Central Precocious Puberty and Autonomous Gonadal Activation.

    PubMed

    Macedo, Delanie Bulcão; Silveira, Letícia Ferreira Gontijo; Bessa, Danielle Souza; Brito, Vinicius Nahime; Latronico, Ana Claudia

    2016-01-01

    Precocious puberty has been classically defined as the onset of sexual secondary characteristics in girls younger than 8 years and in boys younger than 9 years. The discovery of potential factors which trigger human puberty is one of the central mysteries of reproductive biology. Several approaches, including mutational analysis of candidate genes, large-scale genome-wide association studies, and (more recently) whole-exome sequencing, have been performed in attempt to identify novel genetic factors that modulate the human hypothalamic-pituitary-gonadal axis, resulting in premature sexual development. In the last two decades, it has been well established that autonomous gonadal activation can be caused by somatic (GNAS) or germline (LHCGR)-activating mutations of genes that encode essential elements for signal transduction of G protein-coupled receptors, resulting in peripheral precocious puberty in McCune-Albright syndrome and testotoxicosis, respectively. More recently, dominant activating and inactivating mutations of excitatory (KISS1/KISS1R) and inhibitory (MKRN3) modulators of gonadotropin-releasing hormone secretion, respectively, were associated with central precocious puberty phenotype. Indeed, loss-of-function mutations of MKRN3, a maternal imprinted gene located at chromosome 15q, currently represent a frequent cause of central precocious puberty diagnosed in families from distinct geographic origins. Here, we review the known genetic defects in central and peripheral precocious puberty. PMID:26680572

  18. A simulation-based "just in time" and "just in place" central venous catheter education program.

    PubMed

    Lengetti, Evelyn; Monachino, Anne Marie; Scholtz, Amy

    2011-01-01

    The authors describe the Central Venous Catheter Dress Rehearsal simulation program. Teaching is conducted at the bedside, which is efficient and cost effective and allows nurses to practice in a safe environment with no harm to the patient. The educators' challenges and remediation strategies are shared. This simulation program has demonstrated improved consistency of practice and knowledge among pediatric nurses. PMID:22108068

  19. Mineral Deposit Data for Epigenetic Base- and Precious-metal and Uranium-thorium Deposits in South-central and Southwestern Montana and Southern and Central Idaho

    USGS Publications Warehouse

    Klein, T.L.

    2004-01-01

    Metal deposits spatially associated with the Cretaceous Boulder and Idaho batholiths of southwestern Montana and southern and central Idaho have been exploited since the early 1860s. Au was first discovered in placer deposits; exploitation of vein deposits in bedrock soon followed. In 1865, high-grade Ag vein deposits were discovered and remained economically important until the 1890s. Early high-grade deposits of Au, Ag and Pb were found in the weathered portions of the veins systems. As mining progressed to deeper levels, Ag and Pb grades diminished. Exploration for and development of these vein deposits in this area have continued until the present. A majority of these base- and precious-metal vein deposits are classified as polymetallic veins (PMV) and polymetallic carbonate-replacement (PMR) deposits in this compilation. Porphyry Cu and Mo, epithermal (Au, Ag, Hg and Sb), base- and precious-metal and W skarn, W vein, and U and Th vein deposits are also common in this area. The world-class Butte Cu porphyry and the Butte high-sulfidation Cu vein deposits are in this study area. PMV and PMR deposits are the most numerous in the region and constitute about 85% of the deposit records compiled. Several types of syngenetic/diagenetic sulfide mineral deposits in rocks of the Belt Supergroup or their equivalents are common in the region and they have been the source of a substantial metal production over the last century. These syngenetic deposits and their metamorphosed/structurally remobilized equivalents were not included in this database; therefore, deposits in the Idaho portion of the Coeur d'Alene district and the Idaho Cobalt belt, for example, have not been included because many of them are believed to be of this type.

  20. The design of future central receiver power plants based on lessons learned from the Solar One Pilot Plant

    SciTech Connect

    Kolb, G.J.

    1991-01-01

    The 10-MW{sub e} Solar One Pilot Plant was the world's largest solar central receiver power plant. During its power production years it delivered over 37,000 MWhrs (net) to the utility grid. In this type of electric power generating plant, large sun-tracking mirrors called heliostats reflect and concentrate sunlight onto a receiver mounted on top a of a tower. The receiver transforms the solar energy into thermal energy that heats water, turning it into superheated steam that drives a turbine to generate electricity. The Solar One Pilot Plant successfully demonstrated the feasibility of generating electricity with a solar central receiver power plant. During the initial 2 years the plant was tested and 4 years the plant was operated as a power plant, a great deal of data was collected relating to the efficiency and reliability of the plant's various systems. This paper summarizes these statistics and compares them to goals developed by the US Department of Energy. Based on this comparison, improvements in the design and operation of future central receiver plants are recommended. Research at Sandia National Laboratories and the US utility industry suggests that the next generation of central receiver power plants will use a molten salt heat transfer fluid rather than water/steam. Sandia has recently completed the development of the hardware needed in a molten salt power plant. Use of this new technology is expected to solve many of the performance problems encountered at Solar One. Projections for the energy costs from these future central receiver plants are also presented. For reference, these projections are compared to the current energy costs from the SEGS parabolic trough plants now operating in Southern California.

  1. A Common Variation in EDAR Is a Genetic Determinant of Shovel-Shaped Incisors

    PubMed Central

    Kimura, Ryosuke; Yamaguchi, Tetsutaro; Takeda, Mayako; Kondo, Osamu; Toma, Takashi; Haneji, Kuniaki; Hanihara, Tsunehiko; Matsukusa, Hirotaka; Kawamura, Shoji; Maki, Koutaro; Osawa, Motoki; Ishida, Hajime; Oota, Hiroki

    2009-01-01

    Shovel shape of upper incisors is a common characteristic in Asian and Native American populations but is rare or absent in African and European populations. Like other common dental traits, genetic polymorphisms involved in the tooth shoveling have not yet been clarified. In ectodysplasin A receptor (EDAR), where dysfunctional mutations cause hypohidrotic ectodermal dysplasia, there is a nonsynonymous-derived variant, 1540C (rs3827760), that has a geographic distribution similar to that of the tooth shoveling. This allele has been recently reported to be associated with Asian-specific hair thickness. We aimed to clarify whether EDAR 1540C is also associated with dental morphology. For this purpose, we measured crown diameters and tooth-shoveling grades and analyzed the correlations between the dental traits and EDAR genotypes in two Japanese populations, inhabitants around Tokyo and in Sakishima Islands. The number of EDAR 1540C alleles in an individual was strongly correlated with the tooth-shoveling grade (p = 7.7 × 10−10). The effect of the allele was additive and explained 18.9% of the total variance in the shoveling grade, which corresponds to about one-fourth of the heritability of the trait reported previously. For data reduction of individual-level metric data, we applied a principal-component analysis, which yielded PC1-4, corresponding to four patterns of tooth size; this result implies that multiple factors are involved in dental morphology. The 1540C allele also significantly affected PC1 (p = 4.9 × 10−3), which denotes overall tooth size, and PC2 (p = 2.6 × 10−3), which denotes the ratio of mesiodistal diameter to buccolingual diameter. PMID:19804850

  2. Elevated serum 25(OH)-vitamin D levels are negatively correlated with molar-incisor hypomineralization.

    PubMed

    Kühnisch, J; Thiering, E; Kratzsch, J; Heinrich-Weltzien, R; Hickel, R; Heinrich, J

    2015-02-01

    To date, the precise etiology of molar-incisor hypomineralization (MIH) is uncertain. Vitamin D plays a key role in hard tissue formation. Therefore, this study aimed to analyze the relationship between serum 25-hydroxy-vitamin D (25(OH)D) status and dental health data obtained from 1,048 children in a 10-year follow-up of the Munich GINIplus and LISAplus birth cohorts. The dental examination included the diagnosis of MIH and recording of (non-)cavitated caries lesions in primary and permanent teeth. Serum 25(OH)D concentrations were taken from blood samples of the 10-year investigation and measured with a fully automated, modular system. Different logistic regression and Poisson hurdle models were calculated. MIH was diagnosed in 13.6% of the study population. Approximately 16.4% of the children demonstrated caries-related defects (D3-4MFS > 0). The mean season-adjusted concentration of 25(OH)D was 75.8 nmol/l (standard deviation 22.0 nmol/l). After adjusting for sex, age, body mass index, parental education, equivalent income, and television/personal computer (TV/PC) viewing hours, a 10 nmol/l increase in serum 25(OH)D concentrations was significantly associated with a lower odds ratio of having MIH (OR = 0.89; P = 0.006). Furthermore, higher 25(OH)D values were associated with a lower number of caries-affected permanent teeth. It is concluded that elevated serum 25(OH)D concentrations were associated with better dental health parameters. PMID:25503610

  3. Synthesis and in vitro transfection efficiency of spermine-based cationic lipids with different central core structures and lipophilic tails.

    PubMed

    Niyomtham, Nattisa; Apiratikul, Nuttapon; Suksen, Kanoknetr; Opanasopit, Praneet; Yingyongnarongkul, Boon-Ek

    2015-02-01

    Twelve spermine-based cationic lipids with four different central core structures (di(oxyethyl)amino, di(oxyethyl)amino carboxy, 3-amino-1,2-dioxypropyl and 2-amino-1,3-dioxypropyl) and three hydrophobic tails (lauric acid, myristic acid and palmitic acid) were synthesized. The liposomes containing lipids and DOPE showed moderate to good in vitro DNA delivery into HeLa cells. GFP expression experiments revealed that liposomes composed of lipids with 3-amino-1,2-dioxypropyl as a central core structure exhibited highest transfection efficiency under serum-free condition. Whereas, lipid with 2-amino-1,3-dioxypropyl core structure showed highest transfection under 10% serum condition. Moreover, the liposomes and lipoplexes composted of these cationic lipids exhibited low cytotoxicity. PMID:25556091

  4. Polytropic index of central plasma sheet ions based on MHD Bernoulli integral

    NASA Astrophysics Data System (ADS)

    Pang, Xuexia; Cao, Jinbin; Liu, Wenlong; Ma, Yuduan; Lu, Haoyu; Yang, Junying; Li, Liuyuan; Liu, Xu; Wang, Jing; Wang, Tieyan; Yu, Jiang

    2015-06-01

    This paper uses the data of Cluster from 2001 to 2009 to study the polytropic processes of central plasma sheet (CPS) ions. We first adopt the approach of MHD Bernoulli integral (MBI) to identify homogeneous streamflow tubes (quasi-invariant MBI regions) and then calculate the polytropic index of ions for those streamflow tubes whose outward electromagnetic energy ratios δ < 0.05. The central plasma sheet is actually a complicated system, which comprises many streamflow tubes with different polytropic relations and the transition layers in between. The polytropic indexes of the CPS ions range from 0.1 to 1.8 and have a quasi-Gaussian distribution. The median polytropic index is 0.93 for AE < 200 nT and 0.91 for AE ≥ 200 nT. Thus, there is no obvious difference between the polytropic indexes of the quiet time and the substorm time CPS ions, which suggests that the thinning and thickening processes of plasma sheet during substorm times do not change obviously the polytropic relation of the CPS ions. The statistical analysis using different δ (δ < 0.05, 0.025, and 0.01) shows that the outward emission of electromagnetic energy is an effective cooling mechanism and can make the polytropic index to decrease and shift toward isobaric. It is inferred that the CPS ions as a whole much likely behave in a way between isobaric and isothermal.

  5. How long has the central-northern Greenland Ice Sheet been melting at the base?

    NASA Astrophysics Data System (ADS)

    Rogozhina, Irina; Petrunin, Alexey G.; Johnson, Jesse V.; Vaughan, Alan P. M.

    2014-05-01

    Ice-penetrating radar studies (Fahnestock et al., 2001) and the deep ice core project NGRIP (Anderson et al., 2004) have identified extensive areas of rapid basal melt under the central-northern Greenland Ice Sheet (GIS). Our new reconstruction of the lithosphere structure in Greenland reveal that strong anomalies in geothermal heat flux are responsible for much of the estimated ice loss through basal melt. We use our coupled lithosphere-GIS model to study the history of basal ice conditions since the Pliocene period and find that the anomalous heat flow has been maintaining basal ice melt throughout the history of Greenland glaciation. Persistence of basal melt water over the course of ~3.5 million years and periodic development of paleo ice streams originating at the anomaly have likely caused considerable erosion of the subglacial bedrock. The erosion is revealed by ice-penetrating radar measurements, and now exerts a geometric control on ice sheet streaming in the eroded region, and possibly the overall geometry of the GIS. Anderson, K. K., et al. (2004), High-resolution record of Northern Hemisphere climate extending into the last interglacial period, Nature, 431(7005), 147-151 Fahnestock, M., W. Abdalati, I. Joughin, J. Brozena, and P. Gogineni (2001), High geothermal heat flow, basal melt, and the origin of rapid ice flow in central Greenland, Science, 294, 2338-2342

  6. Conservation Action Based on Threatened Species Capture Taxonomic and Phylogenetic Richness in Breeding and Wintering Populations of Central Asian Birds

    PubMed Central

    Schweizer, Manuel; Ayé, Raffael; Kashkarov, Roman; Roth, Tobias

    2014-01-01

    Although phylogenetic diversity has been suggested to be relevant from a conservation point of view, its role is still limited in applied nature conservation. Recently, the practice of investing conservation resources based on threatened species was identified as a reason for the slow integration of phylogenetic diversity in nature conservation planning. One of the main arguments is based on the observation that threatened species are not evenly distributed over the phylogenetic tree. However this argument seems to dismiss the fact that conservation action is a spatially explicit process, and even if threatened species are not evenly distributed over the phylogenetic tree, the occurrence of threatened species could still indicate areas with above average phylogenetic diversity and consequently could protect phylogenetic diversity. Here we aim to study the selection of important bird areas in Central Asia, which were nominated largely based on the presence of threatened bird species. We show that although threatened species occurring in Central Asia do not capture phylogenetically more distinct species than expected by chance, the current spatially explicit conservation approach of selecting important bird areas covers above average taxonomic and phylogenetic diversity of breeding and wintering birds. We conclude that the spatially explicit processes of conservation actions need to be considered in the current discussion of whether new prioritization methods are needed to complement conservation action based on threatened species. PMID:25337861

  7. Management of an Endodontic-Periodontal Lesion in a Maxillary Lateral Incisor with Palatal Radicular Groove: A Case Report

    PubMed Central

    Sooratgar, Aidin; Tabrizizade, Mehdi; Nourelahi, Maryam; Asadi, Yasin; Sooratgar, Hosein

    2016-01-01

    The radicular groove is a developmental anomaly that predisposes the tooth to periodontal break-down. Sometimes the situation becomes more complicated by pulp necrosis and development of a combined endodontic-periodontal lesion which is a diagnostic and treatment challenge for the clinician. This report presents the successful management of an endodontic-periodontal lesion in a maxillary lateral incisor that has a developmental palatal radicular groove using a combination of nonsurgical endodontic therapy and periodontal regenerative techniques. Conclusion: The combination of nonsurgical endodontic and periodontal regenerative treatment is a predictable method in treating combined endodontic-periodontal lesions caused by palato-gingival groove. PMID:27141225

  8. Internet-based physician's workbench as user interface for a central medical case repository.

    PubMed

    Kindler, H; Baranov, A E; Fliedner, T M; Mall, H; Engelke, A; Densow, D

    1999-09-01

    Two World Health Organization Radiation Medical Emergency Preparedness and Assistance Network centers have constructed a standardized central repository of acute radiation syndrome case histories. The case histories are stored on a database server. Radiation protection centers can remotely access the database by user-friendly client software over the Internet. Physicians can use the medical information system to retrieve similar case histories for decision support, to improve their medical knowledge by inspecting real case histories, and for research on the acute radiation syndrome. The system architecture is presented and it is shown in detail how the information system can be employed to deliver medical decision support. Dialogue-response times over narrow-bandwidth Internet connections are better than when using conventional World-Wide-Web technology. However, the latter does not require the installation of client software other than a browser. A Java applet as client could combine the advantages of the two approaches. PMID:10522123

  9. Peripherally inserted central catheter: compliance with evidence-based indications for insertion in an inpatient setting.

    PubMed

    Wojnar, Danuta G; Beaman, Margaret L

    2013-01-01

    A randomized, retrospective chart review was conducted at a medium-sized community hospital to verify appropriateness of peripherally inserted central catheter (PICC) use in 49 inpatient patients. Study results support the Infusion Nurses Society recommendation to use PICCs to facilitate either short- or long-term intravenous therapy of vesicants, irritants, and any medications with a pH less than 5 or greater than 9 and osmolarity greater than 600 mOsm/L. All PICC insertion criteria recommended by the Centers for Disease Control and Prevention were met except one--the intended duration of intravenous therapy of more than 6 days. Identical PICC selection criteria are needed to standardize clinical practice. PMID:23823005

  10. Endodontic Management of a Mandibular Incisor Exhibiting Concurrence of Fusion, Talon Cusp and Dens Invaginatus using CBCT as a Diagnostic Aid

    PubMed Central

    Kumar, Varun

    2016-01-01

    Teeth with aberrant anatomy present a challenge to the endodontist. Advanced tools like cone beam computed tomography aid in exploring the details of endodontic architecture in such cases. The aim of this case report is to highlight the advantage of CBCT in endodontic management of teeth with multiple dental anomalies. A mandibular lateral incisor associated with an extraoral sinus tract revealed unusual clinical anatomy. A provisional diagnosis of type III dens in dente was made based on radiographic findings. Considering the complex anatomy, CBCT was advised to get a confirmatory diagnosis. The anatomic details revealed by CBCT differed significantly from the provisional diagnosis. A final diagnosis of concurrence of fusion with a supernumerary tooth, talon cusp and type II dens invaginatus was established and endodontic treatment of the concerned tooth was carried out. Non-surgical endodontic treatment resulted in successful resolution of the sinus tract and healing of the periapical lesion. CBCT, thus proves to be an excellent diagnostic tool for management of teeth with unusual anatomy, paving way for a conservative treatment free of endodontic mishaps. PMID:27042591

  11. Exploring a type of central pattern generator based on Hindmarsh-Rose model: from theory to application.

    PubMed

    Zhang, Dingguo; Zhang, Qing; Zhu, Xiangyang

    2015-02-01

    This paper proposes the idea that Hindmarsh-Rose (HR) neuronal model can be used to develop a new type of central pattern generator (CPG). Some key properties of HR model are studied and proved to meet the requirements of CPG. Pros and cons of HR model are provided. A CPG network based on HR model is developed and the related properties are investigated. We explore the bipedal primary gaits generated by the CPG network. The preliminary applications of HR model are tested on humanoid locomotion model and functional electrical stimulation (FES) walking system. The positive results of stimulation and experiment show the feasibility of HR model as a valid CPG. PMID:25146328

  12. Centralized Monitoring of the Microsoft Windows-based computers of the LHC Experiment Control Systems

    NASA Astrophysics Data System (ADS)

    Varela Rodriguez, F.

    2011-12-01

    The control system of each of the four major Experiments at the CERN Large Hadron Collider (LHC) is distributed over up to 160 computers running either Linux or Microsoft Windows. A quick response to abnormal situations of the computer infrastructure is crucial to maximize the physics usage. For this reason, a tool was developed to supervise, identify errors and troubleshoot such a large system. Although the monitoring of the performance of the Linux computers and their processes was available since the first versions of the tool, it is only recently that the software package has been extended to provide similar functionality for the nodes running Microsoft Windows as this platform is the most commonly used in the LHC detector control systems. In this paper, the architecture and the functionality of the Windows Management Instrumentation (WMI) client developed to provide centralized monitoring of the nodes running different flavour of the Microsoft platform, as well as the interface to the SCADA software of the control systems are presented. The tool is currently being commissioned by the Experiments and it has already proven to be very efficient optimize the running systems and to detect misbehaving processes or nodes.

  13. SENEX: a computer-based representation of cellular signal transduction processes in the central nervous system.

    PubMed

    Ball, S S; Mah, V H; Miller, P L

    1991-04-01

    The SENEX project is exploring knowledge representation in the neurobiology of ageing through object-oriented programming. SENEX is built from a classification structure of biologic entities and significant relationships among them. For example, an enzyme is an entity and an enzymatic reaction is a relationship among enzyme, cofactor(s), substrate(s) and product(s). There are currently 2600 classes of entities and 50 classes of relationships in SENEX. The class structure serves several functions. One function is to interrelate general and specific categories of molecular and morphologic entities. For example, tyrosine kinase and serine/threonine kinase are specific types of the more general class of protein kinase enzymes. Another function of the class structure is to serve as a network through which inheritance of attributes may occur. For example, the attribute 'subunits' is inherited by all subclasses of the general class multisubunit protein. Information may be accessed through links established in the class structure and through links relating one object as part of another. Relationships form the basis of separate modules within SENEX. This paper describes the types of relationships currently used and planned in the representation of age-related changes in cellular signal transduction processes of mammalian central nervous systems. We also describe tools for specific retrieval of relationships and for tracing links in complex reaction cascades. Application of these tools to identifying possible signal transduction pathways to guide further exploration through experimentation is discussed. PMID:2059842

  14. An observationally based evaluation of WRF seasonal simulations over the Central and Eastern Pacific

    NASA Astrophysics Data System (ADS)

    Wu, Longtao; Li, J.-L. F.; Pi, Chia-Jung; Yu, Jia-Yuh; Chen, Jen-Ping

    2015-10-01

    This study uses multiple satellite data sets to evaluate seasonal simulations of the Weather Research and Forecasting (WRF) model over Central and Eastern Pacific. Experiments with five different convective parameterizations all show reasonably good performance for precipitation simulations. However, large discrepancies exist in the model-simulated ice clouds compared to CloudSat observations. Underestimations of ice clouds, mainly snow and graupel, are present in the Intertropical Convergence Zone (ITCZ) in all the experiments compared to CloudSat. In the ITCZ, all the experiments show a systematic overestimation of outgoing longwave radiation at the top of the atmosphere and downward shortwave radiation at the surface, along with biased cloud cooling in the middle and upper troposphere and biased cloud warming in the lower troposphere. Vertical motion is enhanced in the ITCZ compared to reanalysis. A weaker low-level circulation over the midlatitude oceans is evidenced in all simulations with an eastward overextension of the South Pacific Convergence Zone and overestimated moisture over the Southern Hemisphere oceans when compared to Special Sensor Microwave/Imager observations. Sensitivity experiment demonstrates that doubling the radiative effect of snow can reduce high biases in vertical motion within the ITCZ and improve the large-scale circulation and moisture over the midlatitude oceans.

  15. The beaver Anchitheriomys from the Miocene of Central Europe

    SciTech Connect

    Stefen, C.; Mors, T.

    2008-09-15

    New finds of teeth and mandibles of Anchitheriomys from the Hambach opencast lignite mine in Northwest Germany and the first detailed descriptions of other mandibles from South Germany and Switzerland allow a review of the Central European specimens of this rare beaver genus. The metric variation of cheek teeth and especially the great differences in dimensions of incisors can be much better assessed. The observed range in size can be attributed to ontogenetic changes, and all material is assigned to Anchitheriomys suevicus. Stratigraphically, this species is restricted to the early middle Miocene, European Mammalian Neogene biozones MN 5-6.

  16. Endo-esthetic Management of Permanent Maxillary Lateral Incisor with Severe Root Dilaceration in a 12-year-old Child

    PubMed Central

    Chaugule, Vishwas; Bhat, Chetan; Patil, Vishwas; Shah, Krupali; Vihapure, Shirish

    2008-01-01

    Functional, esthetic and endodontic restoration of a pulpally involved permanent incisor with root dilaceration often presents a daunting clinical challenge. The outcome of conventional treatment modalities like surgical removal of the tooth followed by orthodontic closure of the space is time consuming and esthetically compromising. Even the prosthetic and implantalogical rehabilitation after extraction is not possible until the patient reaches certain age; while the compliance is a problem with the use of removable partial denture in young children. Autoalloplastic anterior tooth transplantation can lead to physical and psychological trauma in a young individual. Thus endo-esthetic management of such teeth helps in maintaining both morphology and esthetics in a growing child until the permanent long lasting prosthetic solution is sought after the complete development of the dentition and jaws. This treatment option for a pulpally involved permanent incisor with root dilaceration involves completing the endodontic treatment in a partially calcified and aberrantly located root canal followed by the use of light transmitting fiber post and core build up using composite resin. PMID:25206086

  17. Micro-CT evaluation of the radioprotective effect of resveratrol on the mandibular incisors of irradiated rats.

    PubMed

    Barbosa, Gabriella Lopes de Rezende; Pimenta, Luiz André; Almeida, Solange Maria de

    2016-01-01

    The purpose of this study was to perform a microcomputed tomographic evaluation of the radioprotective effect of resveratrol on the volume of mandibular incisors of irradiated rats. A second aim was to make a quantitative assessment of the effect of x-ray exposure on these dental tissues. Twenty adult male rats were divided into four groups: control, irradiated control, resveratrol, and irradiated resveratrol. The resveratrol groups received 100 mg/kg of resveratrol, whereas the irradiated groups were exposed to 15 Gy of irradiation. The animals were sacrificed 30 days after the irradiation procedure, and their mandibles were removed and scanned in a microcomputed tomography unit. The images were loaded into Mimics software to allow segmentation of the mandibular incisor and assessment of its volume. The results were compared by One-way ANOVA and Tukey's post hoc test, considering a 5% significance level. The irradiated groups showed significantly diminished volumes of the evaluated teeth, as compared with the control group (p < 0.05). The resveratrol group presented higher values than those of the irradiated groups, and volumes similar to those of the control group. High radiation doses significantly affected tooth formation, resulting in alterations in the dental structure, and thus lower volumes. Moreover, resveratrol showed no effective radioprotective impact on dental tissues. Future studies are needed to evaluate different concentrations of this substance, in an endeavor to verify its potential as a radioprotector for these dental tissues. PMID:26981750

  18. Effect of Ligation Method on Maxillary Arch Force/Moment Systems for a Simulated Lingual Incisor Malalignment

    PubMed Central

    Seru, Surbhi; Romanyk, Dan L; Toogood, Roger W; Carey, Jason P; Major, Paul W

    2014-01-01

    Introduction: The objectives of this study were to determine whether there is a difference in the magnitude of forces and moments produced by elastic ligation when compared to passive ligation, and whether these forces and moments propagate differently along the arch for the two ligation types. A lingual incisor malalignment was used in this study. Methods: The Orthodontic Simulator (OSIM) was used to quantify the three-dimensional forces and moments applied on the teeth given a lingually displaced incisor. A repeated measures MANOVA was performed to statistically analyze the data. Results: The interaction factor illustrated convincing evidence that there is a difference in maximum force and moment values for all outcome variables between ligation types considering all tooth positions along the arch. The mean differences for FX and FY between ligation types were found to be clinically significant, with values for elastic ligation consistently higher than passive ligation. Conclusion: It was found that the maximum forces and moments produced by elastic ligation are greater than those produced by passive ligation and that the magnitude of this difference for the mesiodistal and buccolingual forces is clinically relevant. Additionally, it was determined that elastic ligation causes forces and moments to propagate further along the arch than passive ligation for all outcome variables. PMID:25400715

  19. Temperature changes on the root surfaces of mandibular incisors after an 810-nm high-intensity intracanal diode laser irradiation

    NASA Astrophysics Data System (ADS)

    da Fonseca Alvarez, Andrea; Moura-Netto, Cacio; Daliberto Frugoli, Alexandre; Fernando, Casemiro; Correa Aranha, Ana Cecilia; Davidowicz, Harry

    2012-01-01

    Temperature changes caused by laser irradiation can promote damage to the surrounding dental tissues. In this study, we evaluated the temperature changes of recently extracted human mandibular incisors during intracanal irradiation with an 810-nm diode laser at different settings. Fifty mandibular incisors were enlarged up to an apical size of ISO No. 40 file. After the final rinse with 17% ethylenediaminetetraacetic acid, 0.2% lauryl sodium sulfate biologic detergent, and sterile water, samples were irradiated with circular movements from apex to crown through five different settings of output power (1.5, 2.0, 2.5, 3.0, and 3.5 W) in continuous mode. The temperature changes were measured on both sides of the apical and middle root thirds using two thermopar devices. A temperature increase of 7 C was considered acceptable as a safe threshold when applying the diode laser. Results: The results showed that only 3.5-W output power increased the outer surface temperature above the critical value. Conclusion: The recommended output power can be stipulated as equal to or less than 3 W to avoid overheating during diode laser irradiation on thin dentin walls.

  20. Fracture resistance of cementum-extended composite fillings in severely damaged deciduous incisors: An in vitro study

    PubMed Central

    Seraj, Bahman; Ehsani, Sara; Taravati, Shirin; Ghadimi, Sara; Fatemi, Mostafa; Safa, Sahar

    2014-01-01

    Objective: The aim of this study was to comparatively assess the fracture resistance of the cementum-extended and conventional composite fillings with or without intracanal composite posts in severely damaged deciduous incisors. Materials and Methods: This in vitro study was performed on 60 extracted deciduous maxillary incisors that were randomly divided into four groups: Group 1: Composite filling (CF); Group 2: Composite filling with composite posts (CF + CP); Group 3: Composite filling extended 0.5 mm to cementum (ceCF); Group 4: Composite filling extended 0.5 mm to cementum with composite posts (ceCF + CP). The fracture resistance was assessed by exerting a progressively increasing load with a cross-head speed of 0.5 mm/min in a Universal Testing Machine. Statistical Analysis: Data were analyzed by SPSS-18 using one-way analysis of variance at α < 0.05. Results: The mean fracture resistance (MFR) values of the experimental groups were 410.57 ± 139.44 N, 564.44 ± 92.63 N, 507.5 ± 76.37 N and 601.08 ± 96.04 N. A significant difference was found between the MFR of Groups 1 and 2, Groups 1 and 4 and Groups 3 and 4 (P < 0.05). Conclusion: A superior outcome was achieved by intracanal composite posts in both conventional and cementum-extended composite fillings. PMID:25512722

  1. Endodontic and periodontal management of a severely affected maxillary lateral incisor having combined mucosal fenestration and palatogingival groove

    PubMed Central

    Sharma, Sarang; Srivastava, Dhirendra; Sood, Vishal; Yadav, Priya

    2015-01-01

    Mucosal fenestrations, wherein the tooth root apices are clinically discernible in the oral cavity subsequent to loss of overlying alveolar bone and mucosa, are rare pathologic entities. Palato gingival grooves- anatomic aberrations are also infrequent occurrences that notoriously predispose to periodontal pathologies of varying extent. Both conditions independently are known to popularly affect maxillary lateral incisors. Coexistent fenestration defect and palato gingival groove in the same tooth is extremely rare and undoubtedly is a perfect combination to precipitate severe endodontic-periodontal consequences. In this report, a 34-year-old patient presented to the dental department with complaint of esthetics in relation to exposed root of right maxillary lateral incisor. On closer inspection, a palato gingival groove in addition to fenestration defect was evident on the root surface along with a periodontal pocket of >5 mm. An interdisciplinary treatment was instituted which included endodontic treatment followed by root end resection, osseous bone graft placement and guided tissue regeneration procedures for repair of mucosal fenestration defect. Debridement of the palatal pocket, with saucerization of the groove and restoration with glass ionomer cement were simultaneously employed to correct the palatal defect. PMID:26229283

  2. The central role of chloride in the metabolic acid-base changes in canine parvoviral enteritis.

    PubMed

    Burchell, Richard K; Schoeman, Johan P; Leisewitz, Andrew L

    2014-04-01

    The acid-base disturbances in canine parvoviral (CPV) enteritis are not well described. In addition, the mechanisms causing these perturbations have not been fully elucidated. The purpose of the present study was to assess acid-base changes in puppies suffering from CPV enteritis, using a modified strong ion model (SIM). The hypothesis of the study was that severe acid-base disturbances would be present and that the SIM would provide insights into pathological mechanisms, which have not been fully appreciated by the Henderson-Hasselbalch model. The study analysed retrospective data, obtained from 42 puppies with confirmed CPV enteritis and 10 healthy control dogs. The CPV-enteritis group had been allocated a clinical score, to allow classification of the data according to clinical severity. The effects of changes in free water, chloride, l-lactate, albumin and phosphate were calculated, using a modification of the base excess algorithm. When the data were summated for each patient, and correlated to each individual component, the most important contributor to the metabolic acid-base changes, according to the SIM, was chloride (P<0.001). Severely-affected animals tended to demonstrate hypochloraemic alkalosis, whereas mildly-affected puppies had a hyperchloraemic acidosis (P=0.007). In conclusion, the acid-base disturbances in CPV enteritis are multifactorial and complex, with the SIM providing information in terms of the origin of these changes. PMID:24613416

  3. Structure tensor based automated detection of macular edema and central serous retinopathy using optical coherence tomography images.

    PubMed

    Hassan, Bilal; Raja, Gulistan; Hassan, Taimur; Usman Akram, M

    2016-04-01

    Macular edema (ME) and central serous retinopathy (CSR) are two macular diseases that affect the central vision of a person if they are left untreated. Optical coherence tomography (OCT) imaging is the latest eye examination technique that shows a cross-sectional region of the retinal layers and that can be used to detect many retinal disorders in an early stage. Many researchers have done clinical studies on ME and CSR and reported significant findings in macular OCT scans. However, this paper proposes an automated method for the classification of ME and CSR from OCT images using a support vector machine (SVM) classifier. Five distinct features (three based on the thickness profiles of the sub-retinal layers and two based on cyst fluids within the sub-retinal layers) are extracted from 30 labeled images (10 ME, 10 CSR, and 10 healthy), and SVM is trained on these. We applied our proposed algorithm on 90 time-domain OCT (TD-OCT) images (30 ME, 30 CSR, 30 healthy) of 73 patients. Our algorithm correctly classified 88 out of 90 subjects with accuracy, sensitivity, and specificity of 97.77%, 100%, and 93.33%, respectively. PMID:27140751

  4. The regime of aerosol optical depth over Central Asia based on MODIS Aqua Deep Blue data

    NASA Astrophysics Data System (ADS)

    Floutsi, Athina; KorrasCarraca, Marios; Matsoukas, Christos; Biskos, George

    2015-04-01

    Atmospheric aerosols, both natural and anthropogenic, can affect the regional and global climate through their direct, indirect, and semi-direct effects on the radiative energy budget of the Earth-atmosphere system. To quantify these effects it is therefore important to determine the aerosol load, and an effective way to do that is by measuring the aerosol optical depth (AOD). In this study we investigate the spatial and temporal variability of the AOD over the climatically sensitive region of Central Asia (36° N - 50° N, 46° E - 75° E), which has significant sources of both natural and anthropogenic particles. The primary source of anthropogenic particles is fossil fuel combustion occurring mainly at oil refineries in the Caspian Sea basin. Natural particles originate mostly from the two deserts in the region (namely Kara-Kum and Kyzyl-Kum), where persistent dust activity is observed. Another source is the Aral Sea region, which due to its phenomenal desertification also drives an intense salt and dust transport from the exposed sea-bed to the surrounding regions. This transport is of particular interest because of health-hazardous materials contained in the Aral Sea sea-bed. For our analysis we use Level-3 daily MODIS - Aqua Dark Target - Deep Blue combined product, from the latest MODIS collection (006), available in 1° x 1° resolution (about 100 km x 100 km) over the period 2002-2014.Our first results indicate a significant spatial variability of the aerosol load over the study region. The data also show a clear seasonal cycle, with large aerosol load being associated with strong dust activity during spring and summer (AOD up to 0.5), and low during autumn and winter (AOD up to 0.4). In spring and summer significant aerosol load is observed in the Garabogazköl basin, Northeast and South-southeast Caspian Sea (offshore North Iran and Azerbaijan), as well as southwest of the Aral Sea. In the later region, the high AOD values can be explained by export of dust from the exposed sea-bed under strong northerly and north-easterly winds, and was found to be slightly larger during summer. From this analysis we have excluded the Aral Sea, over which the AOD values were extreme (up to 2.1 and 1.3 during July and January, respectively). The AOD exhibits statistically-significant increasing trend, with an ~40% mean regional relative change. The changes over are more pronounced over and around the Aral Sea, and are stronger during the warm period of the year (April to September). Our results suggest that these trends are associated with increased dust transport from the exposed Aral Sea sea-bed during the study period, which will be examined with the trends of the frequency and strength of aerosol events over central Asia, as well as their association with the Aral Sea desertification.

  5. Paleoecology and Paleoclimate of Tanjung Formation Deposition, Based on Palynological Data From Siung Malopot, Central Borneo

    NASA Astrophysics Data System (ADS)

    Kristyarin, D. A.; Rahardjo, A. T.; Bambang, P.

    2016-01-01

    The northern part of Barito basin is exposed around Siung Malopot area (Central Kalimantan), showing the late cretaceous basement of andesite lavas and granite intrusion. The basement is unconformably overlied by the rocks of Tanjung formation at middle to late Eocene age. Compressive phase during Miocene and Plio-Pleistocene folded and uplifted all existing rocks, made the rocks become relatively north-south structurally oriented. The exposed Tanjung formation consists of sandstone, mudstone, siltstone with intercalation of coals and thin layers of limestone. These lithologies may represent the upper parts of Tanjung formation. Palynology quantitative study is an approach to identify the palaeoclimate and palaeoecology of a certain sedimentation system. Analyses from 18 samples taken from lithologies of Tanjung formation show the presence of palinomorph fossils associated in Proxapertites operculatus zonation indicating the P18-P20 age intervals, or late eocene age. The ratio of spore and non-spore percentage, as well as the comparison between arboreal pollen (AP) and non-arboreal pollen (NAP) show the significant change of environment from time to time during the deposition of the Tanjung formation, also indicating the climate humidity that became more stabile to the younger ages. From 52 observed taxa in the samples, the ratio of marine versus non-marine taxon indicates the influence of sea-water influx in the sedimentation system, explaining the possible presence of thin limestone intercalations at the upper parts of Tanjung formation. Palynology quantitative study on Tanjung Formation indicates the sedimentation of this formation was in backmangrove environment that tends to become more influenced by marine conditions.

  6. The Generation of Antiphase Oscillations and Synchrony by a Rebound-Based Vertebrate Central Pattern Generator

    PubMed Central

    Merrison-Hort, Robert; Zhang, Hong-Yan; Borisyuk, Roman

    2014-01-01

    Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left–right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency. Spontaneous synchrony bouts are rare in most tadpoles, and they instantly emerge from and switch back to swimming, most frequently within the first second after skin stimulation. Analyses show that only neurons that are active during swimming fire action potentials in synchrony, suggesting both output patterns derive from the same neural circuit. The firing of excitatory descending interneurons (dINs) leads that of other types of neurons in synchrony as it does in swimming. During synchrony, the time window between phasic excitation and inhibition is 7.9 ± 1 ms, shorter than that in swimming (41 ± 2.3 ms). The occasional, extra midcycle firing of dINs during swimming may initiate synchrony, and mismatches of timing in the left and right activity can switch synchrony back to swimming. Computer modeling supports these findings by showing that the same neural network, in which reciprocal inhibition mediates rebound firing, can generate both swimming and synchrony without circuit reconfiguration. Modeling also shows that lengthening the time window between phasic excitation and inhibition by increasing dIN synaptic/conduction delay can improve the stability of synchrony. PMID:24760866

  7. Landslide observation and volume estimation in central Georgia based on L-band InSAR

    NASA Astrophysics Data System (ADS)

    Nikolaeva, E.; Walter, T. R.; Shirzaei, M.; Zschau, J.

    2014-03-01

    The republic of Georgia is a mountainous and tectonically active area that is vulnerable to landslides. Because landslides are one of the most devastating natural hazards, their detection and monitoring is of great importance. In this study we report on a previously unknown landslide in central Georgia near the town of Sachkhere. We used a set of Advanced Land Observation Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR) data to generate displacement maps using interferometric synthetic aperture radar (InSAR). We detected a sliding zone of dimensions 2 km north-south by 0.6 km east-west that threatens four villages. We estimated surface displacement of up to ∼30 cm/yr over the sliding body in the satellite line-of-sight (LOS) direction, with the largest displacement occurring after a local tectonic earthquake. We mapped the morphology of the landslide mass by aerial photography and field surveying. We found a complex set of interacting processes, including surface fracturing, shear and normal faults at both the headwall and the sides of the landslide, local landslide velocity changes, earthquake-induced velocity peaks, and loss in toe support due to mining activity. Important implications that are applicable elsewhere can be drawn from this study of coupled processes. We used inverse dislocation modelling to find a possible dislocation plane resembling the landslide basal décollement, and we used that plane to calculate the volume of the landslide. The results suggest a décollement at ∼120 m depth, dipping at ∼10° sub-parallel to the surface, which is indicative of a translational-type landslide.

  8. A Field-Based Aquatic Life Benchmark for Conductivity in Central Appalachian Streams (Final Report)

    EPA Science Inventory

    Cover of the Field-<span class=Based Aquatic Life Benchmark for Conductivity ...

  9. PROPERLY MANAGED FORAGE-BASED COW-CALF OPERATIONS IN SOUTH CENTRAL FLORIDA ARE ENVIRONMENTALLY FRIENDLY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil P levels in subtropical forage-based beef cattle pastures with BG and RP-G declined from 1988 to 2004. During the past 15 years, there was no build up of Mehlich-1 extractable soil P and other crop nutrients despite annual N and P fertilization. Soil testing of pastures in the subtropics is vi...

  10. A Field-Based Aquatic Life Benchmark for Conductivity in Central Appalachian Streams (Final Report)

    EPA Science Inventory

    Cover of the Field-<span class=Based Aquatic Life Benchmark for Conductivity ...

  11. Assessment of Herbicide Transport in Central Missouri Watersheds Using a Process-Based Index Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Identification of areas at risk for pesticide loss is a necessary requirement for targeting best management practices (BMPs) to the most vulnerable areas within watersheds. To work toward that goal, a process-based index model was developed to assess relative landscape vulnerability to hydrologic lo...

  12. Properly managed forage-based cow-calf operations in south Central Florida are environmentally friendly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil phosphorus levels in subtropical forage-based beef cattle pastures with bahiagrass (BG) and rhizoma peanut – mixed grass (RP-G) declined from 1988 to 2004. During the past 15 years, there was no buildup of Mehlich-1 extractable soil P and other crop nutrients despite annual nitrogen and phospho...

  13. Competency Base for Curriculum Development in Preschool Education: Volume 1; Central Document.

    ERIC Educational Resources Information Center

    Troutt, George , Jr.

    Presented in the first of 4 related documents on the Home-Oriented Preschool Education (HOPE) Program is an overview of the procedures for developing a competency based curriculum for normal preschool Appalachian children up to 6-years-old. Discussed are the investigation's procedural components: rationale; philosophical framework (including…

  14. Central Issues in the Use of Computer-Based Materials for High Volume Entrepreneurship Education

    ERIC Educational Resources Information Center

    Cooper, Billy

    2007-01-01

    This article discusses issues relating to the use of computer-based learning (CBL) materials for entrepreneurship education at university level. It considers CBL as a means of addressing the increased volume and range of provision required in the current context. The issues raised in this article have importance for all forms of computer-based…

  15. Knowledge-Based, Central Nervous System (CNS) Lead Selection and Lead Optimization for CNS Drug Discovery

    PubMed Central

    2011-01-01

    The central nervous system (CNS) is the major area that is affected by aging. Alzheimer’s disease (AD), Parkinson’s disease (PD), brain cancer, and stroke are the CNS diseases that will cost trillions of dollars for their treatment. Achievement of appropriate blood–brain barrier (BBB) penetration is often considered a significant hurdle in the CNS drug discovery process. On the other hand, BBB penetration may be a liability for many of the non-CNS drug targets, and a clear understanding of the physicochemical and structural differences between CNS and non-CNS drugs may assist both research areas. Because of the numerous and challenging issues in CNS drug discovery and the low success rates, pharmaceutical companies are beginning to deprioritize their drug discovery efforts in the CNS arena. Prompted by these challenges and to aid in the design of high-quality, efficacious CNS compounds, we analyzed the physicochemical property and the chemical structural profiles of 317 CNS and 626 non-CNS oral drugs. The conclusions derived provide an ideal property profile for lead selection and the property modification strategy during the lead optimization process. A list of substructural units that may be useful for CNS drug design was also provided here. A classification tree was also developed to differentiate between CNS drugs and non-CNS oral drugs. The combined analysis provided the following guidelines for designing high-quality CNS drugs: (i) topological molecular polar surface area of <76 Å2 (25–60 Å2), (ii) at least one (one or two, including one aliphatic amine) nitrogen, (iii) fewer than seven (two to four) linear chains outside of rings, (iv) fewer than three (zero or one) polar hydrogen atoms, (v) volume of 740–970 Å3, (vi) solvent accessible surface area of 460–580 Å2, and (vii) positive QikProp parameter CNS. The ranges within parentheses may be used during lead optimization. One violation to this proposed profile may be acceptable. The chemoinformatics approaches for graphically analyzing multiple properties efficiently are presented. PMID:22267984

  16. Proxy-based reconstructions of earthquakes and tsunamis over the past millennia, Quidico, central Chile

    NASA Astrophysics Data System (ADS)

    Hong, I.; Ely, L. L.; Horton, B.; Dura, T.; Cisternas, M.

    2013-12-01

    We utilized geomorphic, sedimentological, and stratigraphic methods to describe the relative magnitude of historic tsunamis and better understand the paleoseismic history at Quidico, Chile (38.1° S, 73.2° W). The study site lies within the transition zone between two major subduction-zone earthquake events during the observational period: the great 1960 Mw 9.5 earthquake to the south and the 2010 Mw 8.8 Maule earthquake to the north. Despite Chile's growing need to continue to refine earthquake and tsunami hazards, there are few studies aimed at quantifying the geologic impact of earthquake-rupture overlap through time in this region. A combination of pits, cores, and riverbank exposures provide stratigraphic evidence of 5, laterally-continuous sand layers within the Quidico River floodplain. The sand units display landward thinning and disappear completely from the stratigraphy approximately 1 km inland from the coast, characteristic of tsunami deposits. All of the sand units have similar grain-size distribution, ranging from 70-120 μm, which contrasts with the broader, bimodal distribution of grain size (10-450 μm) from an eolian dune at the site and the coarser grain size (155-430 μm) of the local beach sand. Intervening sediment layers consists of organic-rich silts and peat. AMS radiocarbon dates of Scirpus seeds found in peat directly below each sand layer indicate deposition of the sand layers has occurred within the past 800 years. The surficial sand layer (≤ 2 cm thick) is identified as the deposit from the 2010 tsunami. 137Cs measurements taken above, within, and below the second sand unit (4-7 cm) confirmed 14C results that this layer was deposited by the 1960 tsunami. Preliminary microfossil analysis indicates a slightly more marine diatom assemblage in the 1960 sand layer than in the organic-rich silt units above and below it, indicating a marine incursion. Lithology of the sand layers will further constrain their provenance. Comparison of the chronology of these deposits with the 500-year record of historical earthquakes in this region of Chile will be used to identify which tsunami events are preserved in the stratigraphy at Quidico. This information will help characterize the relative magnitude, preservation pattern, and history of past tsunamis within this transition zone. Correlating this record with additional geologic studies and historic accounts of earthquakes and tsunamis throughout the region will collectively advance our understanding of potential seismic hazards in south-central Chile.

  17. The influence of central neuropathic pain in paraplegic patients on performance of a motor imagery based Brain Computer Interface☆

    PubMed Central

    Vuckovic, A.; Hasan, M.A.; Osuagwu, B.; Fraser, M.; Allan, D.B.; Conway, B.A.; Nasseroleslami, B.

    2015-01-01

    Objective The aim of this study was to test how the presence of central neuropathic pain (CNP) influences the performance of a motor imagery based Brain Computer Interface (BCI). Methods In this electroencephalography (EEG) based study, we tested BCI classification accuracy and analysed event related desynchronisation (ERD) in 3 groups of volunteers during imagined movements of their arms and legs. The groups comprised of nine able-bodied people, ten paraplegic patients with CNP (lower abdomen and legs) and nine paraplegic patients without CNP. We tested two types of classifiers: a 3 channel bipolar montage and classifiers based on common spatial patterns (CSPs), with varying number of channels and CSPs. Results Paraplegic patients with CNP achieved higher classification accuracy and had stronger ERD than paraplegic patients with no pain for all classifier configurations. Highest 2-class classification accuracy was achieved for CSP classifier covering wider cortical area: 82 ± 7% for patients with CNP, 82 ± 4% for able-bodied and 78 ± 5% for patients with no pain. Conclusion Presence of CNP improves BCI classification accuracy due to stronger and more distinct ERD. Significance Results of the study show that CNP is an important confounding factor influencing the performance of motor imagery based BCI based on ERD. PMID:25698307

  18. Evidence-based evaluation of information: the centrality and limitations of systematic reviews.

    PubMed

    Jrvholm, Bengt; Bohlin, Ingemar

    2014-03-01

    This introductory paper considers the value and limitations of the methodology of systematic reviews especially according to the evidence-based movement. It explains some terms and organisations producing systematic reviews. It also discusses controversies. The first concerns the criteria by which the quality of individual studies is assessed, the second the possible effects of the affiliation of some reviewers, and the third the value of formalisation of procedure (i.e. the tensions between formal tools and professional judgments). The article contrasts the evidence-based formalism with other formalisms as those by the Intergovernmental Panel on Climate Change and the International Agency for Research on Cancer. It discusses systematic reviews in social science where interventions are complex, difficult to blind, and depend on context. Systematic reviews in working life research are often focusing on prevention. The formal evidence-based process may devaluate or disregard findings from mechanistic and observational studies. Hence such reviews may falsely conclude that existing knowledge about the risk of the factor is limited or nonexistent. PMID:24553849

  19. GIS-based seismic shaking slope vulnerability map of Sicily (Central Mediterranean)

    NASA Astrophysics Data System (ADS)

    Nigro, Fabrizio; Arisco, Giuseppe; Perricone, Marcella; Renda, Pietro; Favara, Rocco

    2010-05-01

    Earthquakes often represent very dangerouses natural events in terms of human life and economic losses and their damage effects are amplified by the synchronous occurrence of seismically-induced ground-shaking failures in wide regions around the seismogenic source. In fact, the shaking associated with big earthquakes triggers extensive landsliding, sometimes at distances of more than 100 km from the epicenter. The active tectonics and the geomorphic/morphodinamic pattern of the regions affected by earthquakes contribute to the slopes instability tendency. In fact, earthquake-induced groun-motion loading determines inertial forces activation within slopes that, combined with the intrinsic pre-existing static forces, reduces the slope stability towards its failure. Basically, under zero-shear stress reversals conditions, a catastrophic failure will take place if the earthquake-induced shear displacement exceeds the critical level of undrained shear strength to a value equal to the gravitational shear stress. However, seismic stability analyses carried out for various infinite slopes by using the existing Newmark-like methods reveal that estimated permanent displacements smaller than the critical value should also be regarded as dangerous for the post-earthquake slope safety, in terms of human activities use. Earthquake-induced (often high-speed) landslides are among the most destructive phenomena related to slopes failure during earthquakes. In fact, damage from earthquake-induced landslides (and other ground-failures), sometimes exceeds the buildings/infrastructures damage directly related to ground-shaking for fault breaking. For this matter, several hearthquakes-related slope failures methods have been developed, for the evaluation of the combined hazard types represented by seismically ground-motion landslides. The methodologies of analysis of the engineering seismic risk related to the slopes instability processes is often achieved through the evaluation of the permanent displacement potentially induced by an seismic scenario. Such methodologies found on the consideration that the conditions of seismic stability and the post-seismic functionality of engineering structures are tightly related to the entity of the permanent deformations that an earthquake can induce. Regarding the existing simplified procedures among slope stability models, Newmark's model is often used to derive indications about slope instabilities due to earthquakes. In this way, we have evaluated the seismically-induced landslides hazard in Sicily (Central Mediterranean) using the Newmark-like model. In order to determine the map distribution of the seismic ground-acceleration from an earthquake scenario, the attenuation-law of Sabetta & Pugliese has been used, analyzing some seismic recordings occurred in Italy. Also, by evaluating permanent displacements, the correlation of Ambraseys & Menu has been assumed. The seismic shaking slope vulnerability map of Sicily has been carried out using GIS application, also considering max seismic ground-acceleration peak distribution (in terms of exceedance probability for fixed time), slope acclivity, cohesion/angle of internal friction of outcropping rocks, allowing the zoning of the unstable slopes under seismic forces.

  20. Successful Implementation of a Unit-based Quality Nurse to Reduce Central Line-associated Bloodstream Infections

    PubMed Central

    Thom, Kerri A.; Li, Shanshan; Custer, Melissa; Preas, Michael Anne; Rew, Cindy D.; Cafeo, Christina; Leekha, Surbhi; Caffo, Brian S.; Scalea, Thomas M.; Lissauer, Matthew E.

    2013-01-01

    Background Central line-associated bloodstream infections (CLABSI) are an important cause of patient morbidity and mortality. Novel strategies to prevent CLABSI are needed. Methods We described a quasi-experimental study to examine the effect of the presence of a unit-based quality nurse (UQN), dedicated to perform patient safety and infection control activities with a focus on CLABSI reduction, on CLABSI rates in a surgical intensive care unit (SICU). Results From July 2008 to March 2012 there were 3257 SICU admissions; central line (CL) utilization ratio was 0.74 (18,193 CL days/24,576 patient days). The UQN program began in July 2010; the nurse was present for 30% (193/518) of the days of the intervention period of July 2010 to March 2012. The average CLABSI rate was 5.0 per 1000 CL days before the intervention and 1.5 after the intervention; and decreased by 5.1% (p = 0.005) for each additional 1% of days of the month that the UQN was present, even after adjusting for CLABSI rates in other adult ICUs, time, severity of illness, and On the CUSP participation (5.1%, p = 0.004). Approximately 11.4 CLABSIs were prevented. Conclusions The presence of a UQN dedicated to perform infection control activities may be an effective strategy for CLABSI reduction. PMID:24360354

  1. Configuring calendar variation based on time series regression method for forecasting of monthly currency inflow and outflow in Central Java

    NASA Astrophysics Data System (ADS)

    Setiawan, Suhartono, Ahmad, Imam Safawi; Rahmawati, Noorgam Ika

    2015-12-01

    Bank Indonesia (BI) as the central bank of Republic Indonesiahas a single overarching objective to establish and maintain rupiah stability. This objective could be achieved by monitoring traffic of inflow and outflow money currency. Inflow and outflow are related to stock and distribution of money currency around Indonesia territory. It will effect of economic activities. Economic activities of Indonesia,as one of Moslem country, absolutely related to Islamic Calendar (lunar calendar), that different with Gregorian calendar. This research aims to forecast the inflow and outflow money currency of Representative Office (RO) of BI Semarang Central Java region. The results of the analysis shows that the characteristics of inflow and outflow money currency influenced by the effects of the calendar variations, that is the day of Eid al-Fitr (moslem holyday) as well as seasonal patterns. In addition, the period of a certain week during Eid al-Fitr also affect the increase of inflow and outflow money currency. The best model based on the value of the smallestRoot Mean Square Error (RMSE) for inflow data is ARIMA model. While the best model for predicting the outflow data in RO of BI Semarang is ARIMAX model or Time Series Regression, because both of them have the same model. The results forecast in a period of 2015 shows an increase of inflow money currency happened in August, while the increase in outflow money currency happened in July.

  2. Object based change detection of Central Asian Tugai vegetation with very high spatial resolution satellite imagery

    NASA Astrophysics Data System (ADS)

    Gärtner, Philipp; Förster, Michael; Kurban, Alishir; Kleinschmit, Birgit

    2014-09-01

    Ecological restoration of degraded riparian Tugai forests in north-western China is a key driver to combat desertification in this region. Recent restoration efforts attempt to recover the forest along with its most dominant tree species, Populus euphratica. The present research observed the response of natural vegetation using an object based change detection method on QuickBird (2005) and WorldView2 (2011) data. We applied the region growing approach to derived Normalized Difference Vegetation Index (NDVI) values in order to identify single P. euphratica trees, delineate tree crown areas and quantify crown diameter changes. Results were compared to 59 reference trees. The findings confirmed a positive tree crown growth and suggest a crown diameter increase of 1.14 m, on average. On a single tree basis, tree crown diameters of larger crowns were generally underestimated. Small crowns were slightly underestimated in QuickBird and overestimated in Worldview2 images. The results of the automated tree crown delineation show a moderate relation to field reference data with R20052: 0.36 and R20112: 0.48. The object based image analysis (OBIA) method proved to be applicable in sparse riparian Tugai forests and showed great suitability to evaluate ecological restoration efforts in an endangered ecosystem.

  3. Wetlands Maps of Central Canada based on L-band SAR Imagery

    NASA Astrophysics Data System (ADS)

    Whitcomb, J.; Moghaddam, M.; Clewley, D.; McDonald, K. C.; Podest, E.; Chapman, B. D.

    2013-12-01

    Many boreal wetlands appear to be evolving into significant sources of greenhouse gases. The ability to accurately quantify the locations, types, and extents of northern wetlands is important to understanding their role in the global carbon cycle and responses to changes in climate. However, due to the extent of boreal wetlands and their inaccessibility, there have been few maps produced of this important ecosystem. To address this need, we have been constructing high-resolution (100 m) thematic maps of North American boreal wetlands. The maps are developed using space-based synthetic aperture radar (SAR), which is capable of efficiently providing high-resolution imagery of vast and often inaccessible regions. Unlike optical imagery, space-based SAR imagery is unaffected by cloud cover. Additionally, L-band SAR is able to sense vegetation structure and moisture content, as well as ground and surface water characteristics (even under vegetation canopies), thereby providing information unobtainable from optical sensors. Space-based L-band SAR thus constitutes an excellent tool for mapping boreal wetlands. One wetlands map is based on HH-polarized L-band SAR imagery from the Japanese Earth Resources Satellite (JERS-1), collected for both summer and winter in the late 1990s. A second map is based on dual-polarized (HH and HV) imagery from the Phased Array L-band SAR (PALSAR) sensor, collected in the summer of 2007. Prior to classification, a sequence of preprocessing steps are executed, including filtering, mosaicking, resampling, reprojection, co-registration, and the formation of supplementary data layers such as image texture, topographic slope, and proximity to water. This preprocessing is implemented by a semi-automated software suite specifically designed to handle the large volumes of data involved in the project. Training/testing data needed in the classification process are formed by merging national wetland inventory and land cover databases. Finally, a 'Random Forests' decision tree classifier takes in the processed SAR and other data layers, along with the training/testing data, and uses them to produce a thematic wetlands map. The accuracy of the resulting classification product is quantified by calculating producer and user error statistics for all validation pixels within the mapped region. Thematic change maps are generated from the SAR-derived maps, thereby allowing decadal changes in wetland extent and type to be identified. These change maps provide information on wetland dynamics and responses to anthropogenic and climatic influences over a large spatial area. This work was done in part within the ALOS Kyoto & Carbon Initiative, with portions carried out at the University of Southern California and at the Jet Propulsion Laboratory under contract to National Aeronautics and Space Administration. PALSAR data were provided by JAXA/EORC and the Alaska Satellite Facility.

  4. A conodont-based standard reference section in central Nevada for the lower Middle Ordovician Whiterockian Series

    USGS Publications Warehouse

    Sweet, W.C.; Ethington, Raymond L.; Harris, A.G.

    2005-01-01

    Ranges of conodonts in stratigraphic sections at five localities in the Monitor and Antelope ranges of central Nevada are used graphically to assemble a standard reference section for the lower Middle Ordovician Whiterockian Series. The base of the series is officially 0.3 m above the base of the Antelope Valley Limestone in the stratotype in Whiterock Canyon (Monitor Range). The top is the level at which Baltoniodus gerdae makes a brief appearance in an exposure of the Copenhagen Formation on the flanks of Hill 8308 in the western Antelope Range. Graphic compilation of the sections considered in this report also indicates that a level correlative with the base of the Whiterockian Series in the stratotype section is 66 m above the base of the Antelope Valley Limestone in its de facto type section on Martin Ridge in the eastern part of the Monitor Range. Ranges, diversity, and the composition of the conodont faunas differ markedly in lithofacies adjacent to the basal boundary of the series; hence we are unable to identify a single conodont species, in a credible developmental sequence, to serve as biological marker of that boundary.

  5. Central odontogenic fibroma of the maxilla

    PubMed Central

    El Harti, Karima; Oujilal, Abdelilah; El Wady, Wafaa

    2015-01-01

    Central odontogenic fibroma (COF) is an uncommon tumor that accounts for 0.1% of all odontogenic tumors; it has been defined as a benign neoplasm of the jaw. Clinically, the lesion grows slowly and leads to cortical expansion. Radiologically, the most common finding is multilocular radiolucency. The lesions are associated with the crown of an unerupted molar, premolar, or incisor tooth and in some cases, with root resorption or displacement. Histologically, the lesion is characterized by mature collagen fibers and numerous fibroblasts. COF responds well to surgical enucleation with no tendency for malignancy or recurrence. We report a case of a 15-year-old female patient presented with painless swelling of the left side of the maxilla since her childhood. Radiographs revealed an expanding ill-defined radiolucency with a displacement of the adjacent tooth. The impacted tooth was pushed posteriorly. The lesion was removed surgically. There were no postoperative complications. PMID:26752885

  6. GIS-based landslide hazard assessment at regional scale in Sicily (Central Mediterranean)

    NASA Astrophysics Data System (ADS)

    Nigro, Fabrizio; Pisciotta, Antonino; Perricone, Marcella; Renda, Pietro; Favara, Rocco

    2010-05-01

    The presence, type and abundance of landslides in an area depend on the characteristics of the triggers and on the predisposing conditions. Natural conditions that control these factors include the local and regional morphological and lithological setting, the presence and abundance of geological discontinuities including bedding planes, faults, joints, and cleavage systems, the type and depth of the soil, the extent and type of the vegetation cover, and the mechanical and hydrological properties of the rocks and soils. In order to evaluate the landslides susceptibility requires understanding of spatial distribution of all these factors that control slope instability. They depend on intrinsic and extrinsic variables. Intrinsic variables determining hazards include bedrock geology, topography, soil depth, soil type, slope gradient, slope aspect, slope curvature, elevation, engineering properties of the slope material, land use pattern and drainage patterns. Extrinsic variables include heavy rainfall, earthquakes and volcanic activities. Although the probability of landslide occurrence depends on both intrinsic and extrinsic variables, the latter possess a temporal distribution which is more difficult to handle in modelling practice. Therefore, for landslide hazard assessment, "landslide susceptibility mapping" is often conducted in which the extrinsic variables are not considered in determining the probability of landslide occurrence. The landslide susceptibility zoning methods mainly applied are: qualitative, statistical methodologies, and geotechnical/safety factor models. Qualitative approaches are based on the judgment of those conducting the susceptibility or hazard assessment; the statistical approach uses a predictive function or index derived from a combination of weighted factors; and the deterministic, models are based on the physical laws of conservation of mass, energy, and momentum. Regarding the statistical methodologies, the combination of factors that have led to landslides in the past are determined and quantitative predictions are made for areas currently free of landslides. In these methods the use of complex statistics requires the collection of large amounts of data to produce reliable results. Instead, deterministic landslide hazard maps normally provide the most detailed results, expressing the hazard in absolute values in the form of safety factors, or the probability of failure given a set of boundary conditions for groundwater levels and seismic acceleration. A methodology for landslide susceptibility mapping of the Sicily using a GIS technology is presented, based on a weighted approach. The degree of susceptibility was weighted considering the extrinsic variable of rainfall and the prevalence of the condition of geology, elevation, slope and land cover. Finally, an overlay analysis is carried out by evaluating the layers obtained according to their weight, and the landslide susceptibility map is produced. The study area was classified into five classes of relative landslide susceptibility, namely, very low, low, moderate, high and very high.

  7. [Evidence-based treatment of ADHD/DAMP in children and adolescents with central stimulants].

    PubMed

    Dalsgaard, S; Thomsen, P H

    2001-02-19

    The use of stimulants in the treatment of children and adolescents with Attention Deficit Hyperactivity Disorder, ADHD, and Deficit in Attention, Motor Control and Perception, DAMP, is often considered somewhat controversial. It was first used in 1937, and since the 1960s, 3000 published studies and 250 reviews have demonstrated the positive, short-term effect of stimulants on children and adolescents with ADHD/DAMP. More than 160 randomised, controlled trials (RCT) have studied the effect of attention, hyperactivity, and impulsivity. Furthermore, stimulants have proved effective on the social relation of such children, both in their families and in with their peers. Side effects are often mild, transient and dose-related. The short-term effectiveness of stimulants is thus well-documented and their prescription evidence-based, whereas further studies on the long-term effect are needed. PMID:11242674

  8. Dynamics and Central Black Hole of NGC 3377 Based on Sauron and Oasis 2D Spectroscopic Observations

    NASA Astrophysics Data System (ADS)

    Copin, Y.; Cretton, N.; Emsellem, E.; Bacon, R.; Davies, R.; de Zeeuw, T.

    2002-01-01

    We have constrained the central black hole mass and dynamical structure of the E6 galaxy NGC 3377, using axisymmetric dynamical models based on Schwarzschild's orbit method. These models fit simultaneously two sets of 2D-kinematic constraints: i) 475 SAURON spectra, covering the inner 41" x 33" at a spatial resolution of 0.95" and ii) 153 OASIS spectra, covering the inner 4" x 2" at 0.25" resolution. The large radii constraints of SAURON help to fix the dynamical structure of NGC 3377's main body, whereas the higher resolution data from OASIS pin down the black hole mass. I will also describe what kind of improvement in the models is needed to satisfy the increased number of data (compared to the "classical" long-slit spectroscopy).

  9. Effect of central mode on the dielectric tunability of ferroelectrics near room temperature: a first-principle-based study.

    PubMed

    Weerasinghe, Jeevaka; Wang, Dawei; Bellaiche, L

    2013-06-26

    First-principles-based effective Hamiltonian molecular dynamics simulations are performed to investigate GHz-THz dynamical properties of bulk and epitaxially strained film made of SrTiO3 near room temperature. Our simulations confirm the huge dielectric tunability recently observed in films. Moreover, universal phenomenological laws, with bulk-like parameters, are found to describe reasonably well the dielectric tunability-versus-dc electric field curves in both systems at low and high electric fields, except for the sole case of the STO film in the low-field regime. Such deviation originates from the presence of a central mode in this low-dimensional system. A revised equation, arising from an original analysis of the simulations, is proposed for modeling this latter situation. PMID:23719129

  10. A new species of Centropages (Copepoda: Calanoida: Centropagidae) from the central Red Sea based on morphological and molecular evidence.

    PubMed

    El-Sherbiny, Mohsen M; Al-Aidaroos, Ali M

    2015-01-01

    Centropages mohamedi sp. nov. (Copepoda: Calanoida) is described from specimens collected in zooplankton samples off Obhur Creek on the Saudi Arabian coast of the central Red Sea. The new species is most closely related to C. orsinii Giesbrecht, 1889, a species described from the Red Sea and widely distributed in the neritic waters of the Indo-West Pacific region. The new species is mainly distinguished by the female genital double somite, male antennules, male leg 4, and leg 5 of both sexes. DNA sequences of the mitochondrial cytochrome C oxidase subunit one (mtCOI) of the two species differ by 20.8%, supporting their morphology-based identification as distinct species.  PMID:25661620

  11. Simulation of a rubber plantation productivity in central Cambodia using the individual-based dynamic vegetation model SEIB-DGVM

    NASA Astrophysics Data System (ADS)

    Kumagai, T.; SATO, H.; Shinjiro, Ph. D., F.

    2013-12-01

    To provide a useful tool for building strategy of forest plantation management, we developed the Spatially Explicit Individual-Based (SEIB) Dynamic Global Vegetation Model (DGVM) applicable to simulate productivity of tree plantations (SEIB-PP). Rubber (Hevea brasiliensis Müll. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers that are being replaced. Describing both primary and latex productivities in rubber plantations via SEIB-PP is, therefore, important to understanding the climatic impacts on productive processes. Model results are compared with measurements collected at a field site in central Cambodia, and here, we show some examples of projections: the rubber plantation production under future climate change conditions.

  12. Centrally controlled self-healing wavelength division multiplexing passive optical network based on optical carrier suppression technique

    NASA Astrophysics Data System (ADS)

    Zhu, Min; Zhang, Jiao; Sun, Xiaohan

    2015-12-01

    We proposed and demonstrated a centrally controlled and self-healing wavelength division multiplexing passive optical network with colorless optical network units (ONUs) based on optical carrier suppression technique. By switching the affected data in the OCS signal sideband to an alternate protection path, only one optical switch is provisioned at the optical line terminal, which is controlled by a logic control circuit upon monitoring of power outage on the working path. The proposed scheme can reliably protect against both distribution and feeder fiber failures. Moreover, gain-saturated reflective semiconductor optical amplifiers are used as colorless transmitters in ONUs. The protection scheme feasibility and system performances are experimentally verified with 10 Gb/s downstream and 1.25 Gb/s upstream data in both working and protection modes. The protection switching time was measured to be around 1 ms.

  13. Outpatient computer-based 32-hour esophageal pH studies teletransmitted to a central esophageal laboratory.

    PubMed

    Falor, W H; Miller, J; Kraus, J; Fannin, S; Taylor, B; Greczanik, V; Steiner, P; Crocker, N

    1985-09-01

    Using a computer-based 32-hour esophageal pH system with a small patient-worn digital recording computer, outpatient studies are performed in the physiologic environment of the patient's workplace and home. Samples are taken at 15-s intervals, and the pH data stored in this computer are then fed into the main computer in the Central Esophageal Laboratory for analysis, scoring, printing out, and storage. Satellite esophageal laboratories located in regional hospitals, clinics, and physicians' offices conduct pH studies by telecommunication, using antimony electrodes, a recording computer, and a modem to transmit data to the main computer for high-quality computer analysis. One main computer and associated personnel serve multiple satellite stations. This maintains patient-physician relationships and is highly cost-effective. PMID:4026492

  14. Are Physiologically Based Pharmacokinetic Models Reporting the Right C(max)? Central Venous Versus Peripheral Sampling Site.

    PubMed

    Musther, Helen; Gill, Katherine L; Chetty, Manoranjenni; Rostami-Hodjegan, Amin; Rowland, Malcolm; Jamei, Masoud

    2015-09-01

    Physiologically based pharmacokinetic (PBPK) models can over-predict maximum plasma concentrations (C(max)) following intravenous administration. A proposed explanation is that invariably PBPK models report the concentration in the central venous compartment, rather than the site where the samples are drawn. The purpose of this study was to identify and validate potential corrective models based on anatomy and physiology governing the blood supply at the site of sampling and incorporate them into a PBPK platform. Four models were developed and scrutinised for their corrective potential. All assumed the peripheral sampling site concentration could be described by contributions from surrounding tissues and utilised tissue-specific concentration-time profiles reported from the full-PBPK model within the Simcyp Simulator. Predicted concentrations for the peripheral site were compared to the observed C(max). The models results were compared to clinical data for 15 studies over seven compounds (alprazolam, imipramine, metoprolol, midazolam, omeprazole, rosiglitazone and theophylline). The final model utilised tissue concentrations from adipose, skin, muscle and a contribution from artery. Predicted C(max) values considering the central venous compartment can over-predict the observed values up to 10-fold whereas the new sampling site predictions were within 2-fold of observed values. The model was particularly relevant for studies where traditional PBPK models over-predict early time point concentrations. A successful corrective model for C(max) prediction has been developed, subject to further validation. These models can be enrolled as built-up modules into PBPK platforms and potentially account for factors that may affect the initial mixing of the blood at the site of sampling. PMID:26100012

  15. A high-order vertex-based central ENO finite-volume scheme for three-dimensional compressible flows

    SciTech Connect

    Charest, Marc R.J.; Canfield, Thomas R.; Morgan, Nathaniel R.; Waltz, Jacob; Wohlbier, John G.

    2015-03-11

    High-order discretization methods offer the potential to reduce the computational cost associated with modeling compressible flows. However, it is difficult to obtain accurate high-order discretizations of conservation laws that do not produce spurious oscillations near discontinuities, especially on multi-dimensional unstructured meshes. A novel, high-order, central essentially non-oscillatory (CENO) finite-volume method that does not have these difficulties is proposed for tetrahedral meshes. The proposed unstructured method is vertex-based, which differs from existing cell-based CENO formulations, and uses a hybrid reconstruction procedure that switches between two different solution representations. It applies a high-order k-exact reconstruction in smooth regions and a limited linear reconstruction when discontinuities are encountered. Both reconstructions use a single, central stencil for all variables, making the application of CENO to arbitrary unstructured meshes relatively straightforward. The new approach was applied to the conservation equations governing compressible flows and assessed in terms of accuracy and computational cost. For all problems considered, which included various function reconstructions and idealized flows, CENO demonstrated excellent reliability and robustness. Up to fifth-order accuracy was achieved in smooth regions and essentially non-oscillatory solutions were obtained near discontinuities. The high-order schemes were also more computationally efficient for high-accuracy solutions, i.e., they took less wall time than the lower-order schemes to achieve a desired level of error. In one particular case, it took a factor of 24 less wall-time to obtain a given level of error with the fourth-order CENO scheme than to obtain the same error with the second-order scheme.

  16. A high-order vertex-based central ENO finite-volume scheme for three-dimensional compressible flows

    DOE PAGESBeta

    Charest, Marc R.J.; Canfield, Thomas R.; Morgan, Nathaniel R.; Waltz, Jacob; Wohlbier, John G.

    2015-03-11

    High-order discretization methods offer the potential to reduce the computational cost associated with modeling compressible flows. However, it is difficult to obtain accurate high-order discretizations of conservation laws that do not produce spurious oscillations near discontinuities, especially on multi-dimensional unstructured meshes. A novel, high-order, central essentially non-oscillatory (CENO) finite-volume method that does not have these difficulties is proposed for tetrahedral meshes. The proposed unstructured method is vertex-based, which differs from existing cell-based CENO formulations, and uses a hybrid reconstruction procedure that switches between two different solution representations. It applies a high-order k-exact reconstruction in smooth regions and a limited linearmore » reconstruction when discontinuities are encountered. Both reconstructions use a single, central stencil for all variables, making the application of CENO to arbitrary unstructured meshes relatively straightforward. The new approach was applied to the conservation equations governing compressible flows and assessed in terms of accuracy and computational cost. For all problems considered, which included various function reconstructions and idealized flows, CENO demonstrated excellent reliability and robustness. Up to fifth-order accuracy was achieved in smooth regions and essentially non-oscillatory solutions were obtained near discontinuities. The high-order schemes were also more computationally efficient for high-accuracy solutions, i.e., they took less wall time than the lower-order schemes to achieve a desired level of error. In one particular case, it took a factor of 24 less wall-time to obtain a given level of error with the fourth-order CENO scheme than to obtain the same error with the second-order scheme.« less

  17. Energy-based Location and Wavefield Polarization Analysis of Tectonic Tremors in Central Mexico

    NASA Astrophysics Data System (ADS)

    Cruz-Atienza, V. M.; Husker, A. L.; Legrand, D.; Kostoglodov, V.

    2013-05-01

    We have designed a location technique based on non-volcanic tremor (NVT) energy measurements and their spatial derivatives in the three ground motion components. By means of a source-scanning grid search and a large database of theoretical Green's functions (i.e. more than 45,000 functions from rake-variable horizontal point dislocations) accounting for both intrinsic attenuation and layered media, the algorithm looks for the hypocentral locations that minimize an error function between observed and synthetic spatial-energy distributions. However, since the energy has little information about the footprint of the source-radiation-pattern on the wavefield polarization we have introduced, into the location algorithm, a particle-motion polarization analysis. The analysis is based on the eigendecomposition of the covariance matrix determined from the three ground motion components, and provides the algorithm with much better control of both NVT location and source mechanism (i.e. dislocation rake angle). Preliminary locations of the NVT catalogue by Husker et al. (2010) for the Guerrero province confirmed the coastward spreading of the NVT activity during the 2006 Slow Slip Event, recently reported. Although the horizontal NVT-energy distribution changes along the one-dimensional MASE array from downdip to updip locations, our results show that this variation may be explained, for all NVT's, with approximately the same rake angle, which differs from the plate convergence direction by 15 to 20 degrees clockwise. Moreover, although a few NVT foci are located within the deep continental crust (i.e. between 30 and 40 km depth), most of the NVT activity is embedded within the subducted slab, below the 40 km depth Moho. Most of the intraslab activity lies between 200 and 240 km from the trench (region called the 'Sweet Spot' by Husker et al., 2012) with 40 to 50 km depth. By superimposing the NVT hypocentral cross-section locations over the state of pore pressure (Pp) computationally modeled within the slab due to the strain field induced by previous Slow Slip Events in the region (Cruz-Atienza et al., 2011), a surprisingly good spatial correlation appears between a low pore-pressure slab segment toward which fluids diffuse and the 'Sweet Spot', where most of the NVT bursts are systematically located.

  18. Wetland Maps of Central Canada based on L-band SAR Imagery

    NASA Astrophysics Data System (ADS)

    Whitcomb, J.; Clewley, D.; Moghaddam, M.; McDonald, K. C.

    2014-12-01

    Northern wetlands have the potential to become major sources of greenhouse gases. Detailed and accurate maps of the locations, types, and extents of these wetlands are therefore essential to the development of accurate carbon budgets. However, due to their vast extent and inaccessibility, most northern wetlands remain unmapped. We have been constructing high-resolution (100 m) thematic maps of boreal wetlands, with current focus on Canadian wetlands. The maps are developed using spaceborne synthetic aperture radar (SAR), which efficiently collects high-resolution imagery over extensive regions and, unlike optical sensors, is unimpaired by clouds or lack of sunlight. Spaceborne L-band (~1.3 GHz) SAR, in particular, records scene characteristics imperceptible to optical sensors such as vegetation structure and moisture content, soil moisture and roughness, and canopy-obscured surface waters. These attributes make it the best single tool for mapping boreal wetlands. Two L-band SAR-based wetland maps are being assembled: one using HH-polarized imagery from the JERS-1 satellite collected in the winter and summer of 1997-1998, and a second using dual-polarized (HH and HV) imagery from the PALSAR sensor of the ALOS satellite collected in the summer of 2008. Ancillary data layers such as image texture, topographic slope, and proximity to water are also generated, and a training/testing data layer is formed by merging polygons from the Canadian Wetland Inventory (CWI) with other land cover databases. A Random Forests decision tree classifier takes as input the SAR, ancillary, and training/testing data layers and uses them to produce thematic wetland maps. The accuracy of each map is quantified via producer and user error statistics. Finally, the SAR-based wetland maps are compared to form a 1998-2008 wetlands change map. Recent advances include a powerful new software suite developed to handle huge volumes of data and much-improved JERS-1 registration. Challenges, including non-GIS-ready CWI data and nonstructural CWI class definitions, are being addressed. This work was carried out in part within the ALOS Kyoto & Carbon Initiative at the University of Southern California and Jet Propulsion Laboratory (JPL) under contract to NASA. JERS-1 mosaics were generated by JPL. PALSAR mosaics were provided by JAXA/EORC.

  19. Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes.

    PubMed

    Reinagel, Adam; Bray Speth, Elena

    2016-01-01

    In an introductory biology course, we implemented a learner-centered, model-based pedagogy that frequently engaged students in building conceptual models to explain how genes determine phenotypes. Model-building tasks were incorporated within case studies and aimed at eliciting students' understanding of 1) the origin of variation in a population and 2) how genes/alleles determine phenotypes. Guided by theory on hierarchical development of systems-thinking skills, we scaffolded instruction and assessment so that students would first focus on articulating isolated relationships between pairs of molecular genetics structures and then integrate these relationships into an explanatory network. We analyzed models students generated on two exams to assess whether students' learning of molecular genetics progressed along the theoretical hierarchical sequence of systems-thinking skills acquisition. With repeated practice, peer discussion, and instructor feedback over the course of the semester, students' models became more accurate, better contextualized, and more meaningful. At the end of the semester, however, more than 25% of students still struggled to describe phenotype as an output of protein function. We therefore recommend that 1) practices like modeling, which require connecting genes to phenotypes; and 2) well-developed case studies highlighting proteins and their functions, take center stage in molecular genetics instruction. PMID:26903496

  20. Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes

    PubMed Central

    Reinagel, Adam; Bray Speth, Elena

    2016-01-01

    In an introductory biology course, we implemented a learner-centered, model-based pedagogy that frequently engaged students in building conceptual models to explain how genes determine phenotypes. Model-building tasks were incorporated within case studies and aimed at eliciting students’ understanding of 1) the origin of variation in a population and 2) how genes/alleles determine phenotypes. Guided by theory on hierarchical development of systems-thinking skills, we scaffolded instruction and assessment so that students would first focus on articulating isolated relationships between pairs of molecular genetics structures and then integrate these relationships into an explanatory network. We analyzed models students generated on two exams to assess whether students’ learning of molecular genetics progressed along the theoretical hierarchical sequence of systems-thinking skills acquisition. With repeated practice, peer discussion, and instructor feedback over the course of the semester, students’ models became more accurate, better contextualized, and more meaningful. At the end of the semester, however, more than 25% of students still struggled to describe phenotype as an output of protein function. We therefore recommend that 1) practices like modeling, which require connecting genes to phenotypes; and 2) well-developed case studies highlighting proteins and their functions, take center stage in molecular genetics instruction. PMID:26903496

  1. Stem and progenitor cell-based therapy of the human central nervous system.

    PubMed

    Goldman, Steve

    2005-07-01

    Multipotent neural stem cells, capable of giving rise to both neurons and glia, line the cerebral ventricles of all adult animals, including humans. In addition, distinct populations of nominally glial progenitor cells, which also have the capacity to generate several cell types, are dispersed throughout the subcortical white matter and cortex. A number of approaches have evolved for using neural progenitor cells in cell therapy. Four strategies are especially attractive for clinical translation: first, transplantation of oligodendrocyte progenitor cells as a means of treating the disorders of myelin; second, transplantation of phenotypically restricted neuronal progenitor cells to treat diseases of discrete loss of a single neuronal phenotype, such as Parkinson disease; third, implantation of mixed progenitor pools to treat diseases characterized by the loss of several discrete phenotypes, such as spinal cord injury; and fourth, mobilization of endogenous neural progenitor cells to restore neurons lost as a result of neurodegenerative diseases, in particular Huntington disease. Together, these may present the most compelling strategies and near-term disease targets for cell-based neurological therapy. PMID:16003375

  2. Treatment of a molasses based distillery effluent in a constructed wetland in central India.

    PubMed

    Billore, S K; Singh, N; Ram, H K; Sharma, J K; Singh, V P; Nelson, R M; Dass, P

    2001-01-01

    A field-scale 4-celled, horizontal subsurface constructed wetland (CW) was installed to evaluate removal efficiencies of wastewater constituents in an industrial distillery effluent. Total and dissolved solids, NH4-N, TKN, P and COD were measured. This CW design provides four serial cells with synthetic liners and a river gravel base. The first two unplanted cells provide preliminary treatment. Specific gravel depths and ensuing biofilm growth provides anaerobic treatment in Cell 1 and anaerobic treatment in Cell 2. Cell 3 was planted with Typha latifolia with an inserted layer of brick rubble (for phosphorus removal). Locally grown reed, Phragmites karka was planted in Cell 4. COD was reduced from 8420 mg/l 3000 from Cell 1 to the outlet of Cell 4. Likewise other parameters: total and dissolved solids, ammonium and total nitrogen, and total P, indicated declining trends at the 4-celled CW effluent. This study reveals how high strength distillery wastewater strongly impacts morphology, aeration anatomy in the chiseled plant tissues, reed growth; and composition of the biofilm in the specialized substratum. The reliability of a CW for organic and nutrients reduction, in association with a poorly performing conventional system is discussed. There is an immense potential for appropriately designed constructed wetlands to improve high strength wastewaters in India. PMID:11804132

  3. A Role for Fragment-Based Drug Design in Developing Novel Lead Compounds for Central Nervous System Targets

    PubMed Central

    Wasko, Michael J.; Pellegrene, Kendy A.; Madura, Jeffry D.; Surratt, Christopher K.

    2015-01-01

    Hundreds of millions of U.S. dollars are invested in the research and development of a single drug. Lead compound development is an area ripe for new design strategies. Therapeutic lead candidates have been traditionally found using high-throughput in vitro pharmacological screening, a costly method for assaying thousands of compounds. This approach has recently been augmented by virtual screening (VS), which employs computer models of the target protein to narrow the search for possible leads. A variant of VS is fragment-based drug design (FBDD), an emerging in silico lead discovery method that introduces low-molecular weight fragments, rather than intact compounds, into the binding pocket of the receptor model. These fragments serve as starting points for “growing” the lead candidate. Current efforts in virtual FBDD within central nervous system (CNS) targets are reviewed, as is a recent rule-based optimization strategy in which new molecules are generated within a 3D receptor-binding pocket using the fragment as a scaffold. This process not only places special emphasis on creating synthesizable molecules but also exposes computational questions worth addressing. Fragment-based methods provide a viable, relatively low-cost alternative for therapeutic lead discovery and optimization that can be applied to CNS targets to augment current design strategies. PMID:26441817

  4. Prevalence of molar incisor hypomineralization in 7–9-year-old children of Bengaluru City, India

    PubMed Central

    Subramaniam, Priya; Gupta, Tulika; Sharma, Akhilesh

    2016-01-01

    Background: Molar incisor hypomineralization (MIH) is a developmental defect. The prevalence of MIH ranges widely from 2.4% to 40.2%. Aim: This study was under taken to determine the prevalence of MIH in 7–9-year-old children of Bengaluru City, India. Materials and Methods: A cross-sectional epidemiological study was conducted in a representative sample of 2500 school children aged 7–9 years of Bengaluru, India. Oral examination was carried out by a single trained calibrated examiner under natural daylight. Results: Twelve children (0.48%) were diagnosed with MIH. A total of 68 teeth were observed with MIH. All four first permanent molars were affected in 50% of children. In the molar group, mandibular molars (29.41%) were more frequently affected than maxillary molars (27.94%). Conclusion: The prevalence of MIH in 7–9-year-old children of Bengaluru was 0.48%, with no gender predilection.

  5. Depressed eruption rate of the rat maxillary incisor in a drug-induced uncompensated hemolytic state model

    SciTech Connect

    Giglio, M.J.; Sanz, A.M.; Bozzini, C.E. )

    1990-03-01

    Female rats weighing about 180 g were separated into two groups. One group (A) received phenylhydrazine (PHZ) every other day during three weeks (for induction of an uncompensated hemolytic state), while the control group (C) received saline. The evidence for the establishment of the uncompensated hemolytic state was obtained by hematocrit value, reticulocyte count, and red-cell-volume-59Fe uptake. Body-weight gain (which is a measure of overall body growth rate), body-length gain (which is a measure of longitudinal skeletal growth rate), food intake, and maxillary incisor eruption rate (ER) were significantly depressed in rats of group A during the PHZ-injection period, in relation to rats of group C. These results indicate that anemia and/or associated factors depress ER, along with body growth and skeletal growth.

  6. [The extraction of a lower incisor in orthodontics: indications, planning of the treatment and clinical handling in different malocclusions].

    PubMed

    Chaqués Asensi, José

    2012-09-01

    The extraction of a lower incisor has been a therapeutic approach considered controversial in orthodontics over the last decades and, therefore, supported by some authors and questioned by others. In recent years, different publications have attempted to provide with substantial and structured information that could help to perform this atypical form of therapy in selected cases with a prospective good result. The purpose of this article is to summarise the available information, providing an order and structure to the diagnostic features that could support the indication and use of this treatment alternative, including the quantification of those parameters that can be measured in the decision-making process. Finally, to set up a clear and meaningful clinical frame that could be used by the orthodontist as a reference line in daily practice. Four case reports will be used in order to illustrate the indication of this treatment modality in different malocclusions. PMID:22944012

  7. A 2000 year varve-based climate record from the central Brooks Range, Alaska

    SciTech Connect

    Bird, BW; Abbott, MB; Finney, BP; Kutchko, B

    2009-01-01

    Varved minerogenic sediments from glacial-fed Blue Lake, northern Alaska, are used to investigate late Holocene climate variability. Varve-thickness measurements track summer temperature recorded at Atigun Pass, located 41 km east at a similar elevation (r (2) = 0.31, P = 0.08). Results indicate that climate in the Brooks Range from 10 to 730 AD (varve year) was warm with precipitation inferred to be higher than during the twentieth century. The varvetemperature relationship for this period was likely compromised and not used in our temperature reconstruction because the glacier was greatly reduced, or absent, exposing sub-glacial sediments to erosion from enhanced precipitation. Varve-inferred summer temperatures and precipitation decreased after 730 AD, averaging 0.4A degrees C above the last millennial average (LMA = 4.2A degrees C) from 730 to 850 AD, and 0.1A degrees C above the LMA from 850 to 980 AD. Cooling culminated between 980 and 1030 AD with temperatures 0.7A degrees C below the LMA. Varve-inferred summer temperatures increased between 1030 and 1620 AD to the LMA, though the period between 1260 and 1350 AD was 0.2A degrees C below the LMA. Although there is no equivalent to the European Medieval Warm Period in the Blue Lake record, two warm intervals occurred from 1350 to 1450 AD and 1500 to 1620 AD (0.4 and 0.3A degrees C above the LMA, respectively). During the Little Ice Age (LIA; 1620 to 1880 AD), inferred summer temperature averaged 0.2A degrees C below the LMA. After 1880 AD, inferred summer temperature increased to 0.8A degrees C above the LMA, glaciers retreated, but aridity persisted based on a number of regional paleoclimate records. Despite warming and glacial retreat, varve thicknesses have not achieved pre-730 AD levels. This reflects limited sediment availability and transport due to a less extensive retreat compared to the first millennium, and continued relative aridity. Overall, the Blue Lake record is similar to varve records from the eastern Canadian Arctic that document a cool LIA and twentieth century warming. However, the occurrence and timing of events, such as the LIA and Medieval Warm Period, varies considerably among records, suggesting heterogeneous climatic patterns across the North American Arctic.

  8. Two takes on the ecosystem impacts of climate change and fishing: Comparing a size-based and a species-based ecosystem model in the central North Pacific

    NASA Astrophysics Data System (ADS)

    Woodworth-Jefcoats, Phoebe A.; Polovina, Jeffrey J.; Howell, Evan A.; Blanchard, Julia L.

    2015-11-01

    We compare two ecosystem model projections of 21st century climate change and fishing impacts in the central North Pacific. Both a species-based and a size-based ecosystem modeling approach are examined. While both models project a decline in biomass across all sizes in response to climate change and a decline in large fish biomass in response to increased fishing mortality, the models vary significantly in their handling of climate and fishing scenarios. For example, based on the same climate forcing the species-based model projects a 15% decline in catch by the end of the century while the size-based model projects a 30% decline. Disparities in the models' output highlight the limitations of each approach by showing the influence model structure can have on model output. The aspects of bottom-up change to which each model is most sensitive appear linked to model structure, as does the propagation of interannual variability through the food web and the relative impact of combined top-down and bottom-up change. Incorporating integrated size- and species-based ecosystem modeling approaches into future ensemble studies may help separate the influence of model structure from robust projections of ecosystem change.

  9. Association between Dental Erosion and Diet in Brazilian Adolescents Aged from 15 to 19: A Population-Based Study

    PubMed Central

    Aguiar, Yêska Paola Costa; dos Santos, Fábio Gomes; Moura, Eline Freitas de Farias; da Costa, Fernanda Clotilde Mariz; Auad, Sheyla Marcia; de Paiva, Saul Martins; Cavalcanti, Alessandro Leite

    2014-01-01

    Dental erosion is a pathological condition resulting from the irreversible dissolution of the mineralized portion of the teeth, being recognized in modern society as an important cause of loss of tooth structure. The aim of this study was to assess the prevalence and its association with diet in Brazilian adolescents of Campina Grande, PB, Brazil. A population-based study was conducted on a stratified sample of 675 adolescents aged from 15 to 19 of both sexes using the index proposed by O'Sullivan. Dental examinations were performed by two calibrated dentists (kappa = 0.82). The significance level adopted was 5%. The prevalence of dental erosion was 21%, and the upper central incisors and lateral incisors were the most affected elements, with 50.5% and 40.2%, respectively. The buccal surface showed greater impairment (51.4%) and 67.8% of teeth with dental erosion had more than half of the surface of affected area. Most damage was on the enamel (93.5%). There were no statistically significant differences between the occurrence of dental erosion and gender, age, socioeconomic status, self-reported ethnicity, and diet. There was high prevalence of dental erosion in its early stages among adolescents and there were no significant differences in the frequency of the consumption of foods and beverages and the presence of dental erosion. PMID:24695943

  10. The effects of incisor inclination changes on the position of point A in Class II division 2 malocclusion using three-dimensional evaluation: a long-term prospective study

    PubMed Central

    Chen, Qiushuo; Zhang, Caixia; Zhou, Yu

    2014-01-01

    Objective: The aim of this study was to evaluate change in the sagittal position of point A due to orthodontic treatment by orthodontic community-cone beam computed tomography (CBCT). Materials and methods: 40 subjects (22 males and 18 females) who had Class II division 2 malocclusion were recruited, and 40 subjects (23 males and 17 females) who had minor crowding in the beginning of the treatment and required no or minimal maxillary anterior tooth movement were served as control. The changes in maxillary incisor inclination, sagittal position of point A, SNA angle, and movement of incisor root apex and incisal edge were calculated before and after CBCT treatment. Results: Maxillary incisors were significantly proclined in the study group but not in the control group. This proclination resulted in 2.95 mm backward movement of the root apex and 6.23 mm forward movement of the incisal edge of maxillary incisors. Point A moved 1.24 mm and 0.18 mm backward in the study and control groups, respectively. Incisor root apex and incisal edge almost remained stable in the control group. No significant change was observed in the SNA angle in both the study and control groups. However, the change in SNA between the two groups was found to be significant. Conclusions: Proclination of maxillary incisors with backward movement of incisor root apex caused posterior movement of point A. This posterior movement significantly affects the SNA angle. PMID:25419382

  11. Effects of guanine bases at the central loop on stabilization of the quadruplex DNAs and their interactions with Meso-tetrakis(N-methylpyridium-4-yl)porphyrin.

    PubMed

    Jeon, Sun Hee; Moon, Jihye; Lee, Myung Won; Kim, Seog K

    2015-10-01

    The thermal stability of the G-quadruplex formed from the thrombin-binding aptamer, 5'G2T2G2TGTG2T2G2, in which the guanine (G) base at the central loop was replaced with an adenine (A) or inosine (I) base, was examined to determine the role of the central G base in stabilizing the quadruplex. Replacement of the central G base by the I base resulted in a slight decrease in thermal stability. On the other hand, the stability of the G-quadruplex decreased to a significant extent when it was replaced with the A base. The optimized structure of the G-quadruplex, which was obtained by a molecular dynamic simulation, showed that the carbonyl group of the C5 position of the central G base could form hydrogen bonds with the G1 amine group at the C7 position on the upper G-quartet. This formation of a hydrogen bond contributes to the stability of the G-quadruplex. The spectral property of meso-tetrakis(N-methylpyridium-4yl)porphyrin (TMPyP) associated with the G-quadruplex was characterized by a moderate red shift and hypochromism in the absorption spectrum, a positive CD signal, and two emission maxima in the fluorescence emission spectrum, suggesting that TMPyP binds at the exterior of the G-quadruplex. Spectral properties were slightly altered when the G base at the central loop was replaced with A or I, while the fluorescence decay times of TMPyP associated with the G-quadruplex were identical. Observed spectral properties removes the possibility of intercalation binding mode for TMPyP. TMPyP binds at the exterior of the quadruplex. Whether it stacks on the central loop or binds at the side of the quadruplex is unclear at this stage. PMID:26057195

  12. Future trends of precipitation-related extremes in Central/Eastern Europe based on regional climate model simulations

    NASA Astrophysics Data System (ADS)

    Pongracz, Rita; Bartholy, Judit; Kis, Anna

    2013-04-01

    For building adequate regional adaptation and mitigation strategies, global climate model (GCM) simulation results must be downscaled. Local-scale analysis requires regional climate models (RCMs) embedded in GCMs providing finer spatial and temporal resolutions, which can better serve end-users' needs. This is especially important in case of precipitation due to the large temporal and spatial variability. Furthermore, the high potential risks of drought events on agricultural production and the possible flood events in the Central/Eastern European area also highlight the importance of this issue. On the base of evaluating raw RCM precipitation outputs of ENSEMBLES model experiments for 1951-2000, simulated values usually significantly overestimate the observations in Central/Eastern Europe, except in summer when mostly underestimations were found. These biases of the raw RCM outputs are corrected using quantile matching technique when the monthly empirical distribution functions of each grid point are fitted to the observed distribution (represented by gridded E-OBS data). Then, the calculated bias correcting factors are applied to the outputs of RCM experiments for the future 2000-2100 period taking into account the SRES A1B emission scenario, according to which CO2 concentration by 2100 is estimated to exceed 700 ppm, i.e., more than twice of the preindustrial level. In order to assess precipitation tendencies in the region, several precipitation-related indices (including the number of wet days using several threshold values, e.g. 5 mm, 10 mm, 20 mm; CDD - the maximum number of consecutive dry days; RX1 - the highest 1-day precipitation amount; RX5 - the greatest 5-day rainfall total; etc.) are analyzed both on annual and seasonal scales. The results clearly suggest that consecutive dry periods in the region are likely to lengthen in the future, especially in summer. Furthermore, extreme precipitation is projected to increase in winter and autumn, especially in the northern part of the selected domain.

  13. A Descriptive Comparison of Ultrasound Guided Central Venous Cannulation of the Internal Jugular to Landmark Based Subclavian Vein Cannulation

    PubMed Central

    Theodoro, Daniel; Bausano, Brian; Lewis, Lawrence; Evanoff, Bradley; Kollef, Marin

    2013-01-01

    The safest site for central venous cannulation (CVC) remains debated. Many emergency medicine physicians advocate the ultrasound guided internal jugular approach (USIJ) because of data supporting its efficiency. However, a number of physicians prefer, and are most comfortable with, the subclavian vein approach. The purpose of this study was to describe adverse event rates among operators using the USIJ approach and the landmark subclavian vein approach without ultrasound (SC). Methods This was a prospective observational trial of patients undergoing CVC of the subclavian or internal jugular veins in the Emergency Department (ED). Physicians performing the procedures did not undergo standardized training in either technique. The primary outcome was a composite of adverse events defined as hematoma, arterial cannulation, pneumothorax, and failure to cannulate. Physicians recorded the anatomical site of cannulation, ultrasound assistance, indications and acute complications. Variables of interest were collected from the pharmacy and ED record. Physician experience was based on a self-reported survey. We followed outcomes of central line insertion until device removal or patient discharge. Results Physicians attempted 236 USIJ and 132 SC cannulations on 333 patients. The overall adverse event rate was 22% with failure to cannulate being the most common. Adverse events occurred in 19% of USIJ attempts compared to 29% of non-ultrasound guided subclavian attempts. Among highly experienced operators CVCs placed at the subclavian site resulted in more adverse events than those performed using USIJ (RR=1.89, 95%CI 1.05 to 3.39). Conclusions While limited by observational design, our results suggest that the USIJ technique may result in fewer adverse events compared to the landmark SC approach. PMID:20370781

  14. Structural interpretation and physical property estimates based on COAST 2012 seismic reflection profiles offshore central Washington, Cascadia subduction zone

    NASA Astrophysics Data System (ADS)

    Webb, S. I.; Tobin, H. J.; Everson, E. D.; Fortin, W.; Holbrook, W. S.; Kent, G.; Keranen, K. M.

    2014-12-01

    The Cascadia subduction zone has a history of large magnitude earthquakes, but a near-total lack of plate interface seismicity, making the updip limit of the seismogenic zone difficult to locate. In addition, the central Cascadia accretionary prism is characterized by an extremely low wedge taper angle, landward vergent initial thrusting, and a flat midslope terrace between the inner and outer wedges, unlike most other accretionary prisms (e.g. the Nankai Trough, Japan). The Cascadia Open Access Seismic Transect (COAST) lines were shot by R/V Marcus Langseth in July of 2012 off central Washington to image this subduction zone. Two trench-parallel and nine trench-perpendicular lines were collected. In this study, we present detailed seismic interpretation of both time- and depth-migrated stacked profiles, focused on elucidating the deposition and deformation of both pre- and syn-tectonic sediment in the trench and slope. Distribution and timing of sediments and their deformation is used to unravel the evolution of the wedge through time. Initially, interpretation of the time-sections is carried out to support the building of tomographic velocity models to aid in the pre-stack depth migration (PSDM) of selected lines. In turn, we use PSDM velocity models to estimate porosity and pore pressure conditions at the base of the wedge and across the basal plate interface décollement where possible, using established velocity-porosity transforms. Interpretation in this way incorporates both accurate structural relationships and robust porosity models to document wedge development and present-day stress state, in particular regions of potential overpressure. Results shed light on the origin and evolution of the mid-slope terrace and the low taper angle for the forearc wedge. This work may shed light ultimately on the position of the potential updip limit of the seismogenic zone beneath the wedge.

  15. Late Quaternary alluvial fan response to climatic and tectonic base-level changes: Jakes Valley, Central Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Stokes, M.; Garcia, A. F.

    2003-12-01

    Late Quaternary alluvial fans within the Jakes Valley region (White Pine County, Central Great Basin) are typically composed of up to 4 inset morphostratigraphic units. These units, Qf0 (oldest) through to Qf3 (youngest), are based upon field relationships (mapping & fan topographic profiles) and soil properties. Distal fan areas contain pluvial lake shoreline features (erosional benches and beach ridges) that record lake-level lowering since the last glacial maximum. Integration of the fan morphostratigraphy and pluvial lake shoreline features allows for the alluvial fan response to climate induced base-level lowering to be investigated. Geochronology is established by AMS C14 dating of gastropod shells sampled from a range of highstand (dates pending) through to lowstand (12,080 +/- 50 rcybp) beach ridges. Detailed analysis of two alluvial fans from the western (Cottonwood Fan) and eastern (Yamaha Fan) basin margins reveals some interesting differences in fan morphostratigraphy. The Cottonwood fan is characterised by a complete suite of morphostratigraphic units (Qf0-Qf3), whilst the Yamaha fan comprises only Qf0 and Qf3. The presence of a pronounced 17 m high scarp feature, some several hundreds of metres in length, within close proximity to the mountain front on the Cottonwood fan, suggests the occurrence of neotectonic activity. This extensional (?) faulting appears to be post QF0 and may have been responsible for influencing the observed stratigraphic differences between the Cottonwood and Yamaha fans via a tectonic lowering of base-level. Within this poster we explore the relative roles of climate and tectonic base-level lowering for alluvial fan development.

  16. The optimal fractional S transform of seismic signal based on the normalized second-order central moment

    NASA Astrophysics Data System (ADS)

    Wang, Yuqing; Peng, Zhenming

    2016-06-01

    As the extension of time-bandwidth product (TBP) in the fractional domain, the generalized time-bandwidth product (GTBP) provides a rotation-independent measure of compactness. A new fractional S transform (FrST) is proposed to avoid missing the physical meaning of the fractional time-frequency plane. FrST is based on the GTBP criterion and the time-frequency rotation property of fractional Fourier transform (FrFT). In addition, we introduce the normalized second-order central moment (NSOCM) calculation method to determine the optimal order. The optimal order searching process can be converted into the NSOCM calculation. Compared with TBP search algorithms, the NSOCM approach has higher computational efficiency. The qualitative advantage of the NSOCM approach in the optimal order selection is demonstrated by a series of model tests. The optimal FrST based on NSOCM (OFrST) can produce more compact time-frequency support than the S transform. The real seismic data spectral decomposition results show that the proposed algorithm can obtain single-frequency visualization with better time-frequency concentration, thereby enhancing the precision of reservoir prediction.

  17. Nanoparticle-based drug delivery to improve the efficacy of antiretroviral therapy in the central nervous system

    PubMed Central

    Gomes, Maria João; Neves, José das; Sarmento, Bruno

    2014-01-01

    Antiretroviral drug therapy plays a cornerstone role in the treatment of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome patients. Despite obvious advances over the past 3 decades, new approaches toward improved management of infected individuals are still required. Drug distribution to the central nervous system (CNS) is required in order to limit and control viral infection, but the presence of natural barrier structures, in particular the blood–brain barrier, strongly limits the perfusion of anti-HIV compounds into this anatomical site. Nanotechnology-based approaches may help providing solutions for antiretroviral drug delivery to the CNS by potentially prolonging systemic drug circulation, increasing the crossing and reducing the efflux of active compounds at the blood–brain barrier, and providing cell/tissue-targeting and intracellular drug delivery. After an initial overview on the basic features of HIV infection of the CNS and barriers to active compound delivery to this anatomical site, this review focuses on recent strategies based on antiretroviral drug-loaded solid nanoparticles and drug nanosuspensions for the potential management of HIV infection of the CNS. PMID:24741312

  18. A Central Support System Can Facilitate Implementation and Sustainability of a Classroom-Based Undergraduate Research Experience (CURE) in Genomics

    PubMed Central

    Lopatto, David; Hauser, Charles; Jones, Christopher J.; Paetkau, Don; Chandrasekaran, Vidya; Dunbar, David; MacKinnon, Christy; Stamm, Joyce; Alvarez, Consuelo; Barnard, Daron; Bedard, James E. J.; Bednarski, April E.; Bhalla, Satish; Braverman, John M.; Burg, Martin; Chung, Hui-Min; DeJong, Randall J.; DiAngelo, Justin R.; Du, Chunguang; Eckdahl, Todd T.; Emerson, Julia; Frary, Amy; Frohlich, Donald; Goodman, Anya L.; Gosser, Yuying; Govind, Shubha; Haberman, Adam; Hark, Amy T.; Hoogewerf, Arlene; Johnson, Diana; Kadlec, Lisa; Kaehler, Marian; Key, S. Catherine Silver; Kokan, Nighat P.; Kopp, Olga R.; Kuleck, Gary A.; Lopilato, Jane; Martinez-Cruzado, Juan C.; McNeil, Gerard; Mel, Stephanie; Nagengast, Alexis; Overvoorde, Paul J.; Parrish, Susan; Preuss, Mary L.; Reed, Laura D.; Regisford, E. Gloria; Revie, Dennis; Robic, Srebrenka; Roecklien-Canfield, Jennifer A.; Rosenwald, Anne G.; Rubin, Michael R.; Saville, Kenneth; Schroeder, Stephanie; Sharif, Karim A.; Shaw, Mary; Skuse, Gary; Smith, Christopher D.; Smith, Mary; Smith, Sheryl T.; Spana, Eric P.; Spratt, Mary; Sreenivasan, Aparna; Thompson, Jeffrey S.; Wawersik, Matthew; Wolyniak, Michael J.; Youngblom, James; Zhou, Leming; Buhler, Jeremy; Mardis, Elaine; Leung, Wilson; Threlfall, Jennifer; Elgin, Sarah C. R.

    2014-01-01

    In their 2012 report, the President's Council of Advisors on Science and Technology advocated “replacing standard science laboratory courses with discovery-based research courses”—a challenging proposition that presents practical and pedagogical difficulties. In this paper, we describe our collective experiences working with the Genomics Education Partnership, a nationwide faculty consortium that aims to provide undergraduates with a research experience in genomics through a scheduled course (a classroom-based undergraduate research experience, or CURE). We examine the common barriers encountered in implementing a CURE, program elements of most value to faculty, ways in which a shared core support system can help, and the incentives for and rewards of establishing a CURE on our diverse campuses. While some of the barriers and rewards are specific to a research project utilizing a genomics approach, other lessons learned should be broadly applicable. We find that a central system that supports a shared investigation can mitigate some shortfalls in campus infrastructure (such as time for new curriculum development, availability of IT services) and provides collegial support for change. Our findings should be useful for designing similar supportive programs to facilitate change in the way we teach science for undergraduates. PMID:25452493

  19. A central support system can facilitate implementation and sustainability of a Classroom-based Undergraduate Research Experience (CURE) in Genomics.

    PubMed

    Lopatto, David; Hauser, Charles; Jones, Christopher J; Paetkau, Don; Chandrasekaran, Vidya; Dunbar, David; MacKinnon, Christy; Stamm, Joyce; Alvarez, Consuelo; Barnard, Daron; Bedard, James E J; Bednarski, April E; Bhalla, Satish; Braverman, John M; Burg, Martin; Chung, Hui-Min; DeJong, Randall J; DiAngelo, Justin R; Du, Chunguang; Eckdahl, Todd T; Emerson, Julia; Frary, Amy; Frohlich, Donald; Goodman, Anya L; Gosser, Yuying; Govind, Shubha; Haberman, Adam; Hark, Amy T; Hoogewerf, Arlene; Johnson, Diana; Kadlec, Lisa; Kaehler, Marian; Key, S Catherine Silver; Kokan, Nighat P; Kopp, Olga R; Kuleck, Gary A; Lopilato, Jane; Martinez-Cruzado, Juan C; McNeil, Gerard; Mel, Stephanie; Nagengast, Alexis; Overvoorde, Paul J; Parrish, Susan; Preuss, Mary L; Reed, Laura D; Regisford, E Gloria; Revie, Dennis; Robic, Srebrenka; Roecklien-Canfield, Jennifer A; Rosenwald, Anne G; Rubin, Michael R; Saville, Kenneth; Schroeder, Stephanie; Sharif, Karim A; Shaw, Mary; Skuse, Gary; Smith, Christopher D; Smith, Mary; Smith, Sheryl T; Spana, Eric P; Spratt, Mary; Sreenivasan, Aparna; Thompson, Jeffrey S; Wawersik, Matthew; Wolyniak, Michael J; Youngblom, James; Zhou, Leming; Buhler, Jeremy; Mardis, Elaine; Leung, Wilson; Shaffer, Christopher D; Threlfall, Jennifer; Elgin, Sarah C R

    2014-01-01

    In their 2012 report, the President's Council of Advisors on Science and Technology advocated "replacing standard science laboratory courses with discovery-based research courses"-a challenging proposition that presents practical and pedagogical difficulties. In this paper, we describe our collective experiences working with the Genomics Education Partnership, a nationwide faculty consortium that aims to provide undergraduates with a research experience in genomics through a scheduled course (a classroom-based undergraduate research experience, or CURE). We examine the common barriers encountered in implementing a CURE, program elements of most value to faculty, ways in which a shared core support system can help, and the incentives for and rewards of establishing a CURE on our diverse campuses. While some of the barriers and rewards are specific to a research project utilizing a genomics approach, other lessons learned should be broadly applicable. We find that a central system that supports a shared investigation can mitigate some shortfalls in campus infrastructure (such as time for new curriculum development, availability of IT services) and provides collegial support for change. Our findings should be useful for designing similar supportive programs to facilitate change in the way we teach science for undergraduates. PMID:25452493

  20. Base surge deposits, eruption history, and depositional processes of a wet phreatomagmatic volcano in Central Anatolia (Cora Maar)

    NASA Astrophysics Data System (ADS)

    Gençalioğlu-Kuşcu, Gonca; Atilla, Cüneyt; Cas, Ray A. F.; Kuşcu, İlkay

    2007-01-01

    Cora Maar is a Quaternary volcano located to the 20 km northwest of Mount Erciyes, the largest of the 19 polygenetic volcanic complexes of the Cappadocian Volcanic Province in central Anatolia. Cora Maar is a typical example of a maar-diatreme volcano with a nearly circular crater with a mean diameter of c.1.2 km, and a well-bedded base surge-dominated maar rim tephra sequence up to 40 m in thickness. Having a diameter/depth ratio ( D/ d) of 12, Cora is a relatively "mature" maar compared to recent maar craters in the world. Cora crater is excavated within the andesitic lava flows of Quaternary age. The tephra sequence is not indurated, and consists of juvenile clasts up to 70 cm, non-juvenile clasts up to 130 cm, accretionary lapilli up to 1.2 cm in diameter, and ash to lapilli-sized tephra. Base surge layers display well-developed antidune structures indicating the direction of the transport. Both progressive and regressive dune structures are present within the tephra sequence. Wavelength values increase with increasing wave height, and with large wavelength and height values. Cora tephra display similarities to Taal and Laacher See base surge deposits. Impact sags and small channel structures are also common. Lateral and vertical facies changes are observed for the dune bedded and planar bedsets. According to granulometric analyses, Cora Maar tephra samples display a bimodal distribution with a wide range of Md φ values, characteristic for the surge deposits. Very poorly sorted, bimodal ash deposits generally vary from coarse tail to fine tail grading depending on the grain size distribution while very poorly sorted lapilli and block-rich deposits display a positive skewness due to fine tail grading.

  1. Application of a process-based shallow landslide hazard model over a broad area in Central Italy

    USGS Publications Warehouse

    Gioia, Eleonora; Speranza, Gabriella; Ferretti, Maurizio; Godt, Jonathan W.; Baum, Rex L.; Marincioni, Fausto

    2015-01-01

    Process-based models are widely used for rainfall-induced shallow landslide forecasting. Previous studies have successfully applied the U.S. Geological Survey’s Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability (TRIGRS) model (Baum et al. 2002) to compute infiltration-driven changes in the hillslopes’ factor of safety on small scales (i.e., tens of square kilometers). Soil data input for such models are difficult to obtain across larger regions. This work describes a novel methodology for the application of TRIGRS over broad areas with relatively uniform hydrogeological properties. The study area is a 550-km2 region in Central Italy covered by post-orogenic Quaternary sediments. Due to the lack of field data, we assigned mechanical and hydrological property values through a statistical analysis based on literature review of soils matching the local lithologies. We calibrated the model using rainfall data from 25 historical rainfall events that triggered landslides. We compared the variation of pressure head and factor of safety with the landslide occurrence to identify the best fitting input conditions. Using calibrated inputs and a soil depth model, we ran TRIGRS for the study area. Receiver operating characteristic (ROC) analysis, comparing the model’s output with a shallow landslide inventory, shows that TRIGRS effectively simulated the instability conditions in the post-orogenic complex during historical rainfall scenarios. The implication of this work is that rainfall-induced landslides over large regions may be predicted by a deterministic model, even where data on geotechnical and hydraulic properties as well as temporal changes in topography or subsurface conditions are not available.

  2. Migrating Ignimbrite Flares in the Central Andes, Implications for Crustal Evolution Based on Chemical, Isotopic, Geochronological, and GIS-Based Volumetric Data

    NASA Astrophysics Data System (ADS)

    Worner, G.; Brandmeier, M.; Freymuth, H.; Heistek, R. M.

    2014-12-01

    Temporal and compositional patterns of Neogene ignimbrites in the Central Andes were analysed using GIS and geostatistical modelling based on 203 digitized ignimbrite sheets for which geochronological, geochemical, and Sr-Nd-Pb-isotopic data on pumices as well as Sr-O isotopes on minerals from selected samples were compiled and compared to compositional and isotopic data from andesite lavas. Composition, timing, volumes and sources of erupted ignimbrite deposits are thus constrained and magma volumes through space and time are calculated. The total erupted ignimbrite magma volume of 31,000 km3 (minimum value) in the past 30 Ma indicate an average magmatic addition of 20-30 km3*Ma/km, similar to the basaltic "base"-flux for arc magmatism. Ignimbrite flare-ups are, however, rather punctuated, short-lived events well separated in space and time. There is a clear N-S "younging" of ignimbrite pulses from N to S at 19-24 Ma, 13-14 Ma, 6-10 Ma and 3-6 Ma. Ignimbrite eruptions occurred in the wake of subduction of the Juan-Fernandez ridge on the Nazca Plate passing below the Central Andes from N to S. Low angle subduction caused compression and fluid release is followed by massive inflow and melting of asthenospheric mantle when the slab steepened again after the passing of the ridge. This in turn caused massive melting within the crust aided by advective heat transport. Differences in chemical and isotopic composition of the large-volume ignimbrites are related to changes in crustal thickness, and different "preconditioning" during the Andean orogeny at a given space in time. Isotope data and whole rock compositional data suggest a higher degree of crustal assimilation for the younger Altiplano ignimbrites in the S (c. 50%) compared to the older (22-19 Ma) ignimbrites in the N were the crustal component is significantly less (20%). REE compositions reflect changes in crustal thickness with a "transition" at c. 13-9 Ma that can be related to accelerated crustal shortening and lower crustal heating at that time. There is no "single" ignimbrite flare up, we suggest a more dynamic scenario, with "flares" moving from N to S across the Central Andes during the past 25 Ma. Our database yield volumes of mantle and crustal magmas produced through time and space and should aid to constrain numerical models of Andean geodynamic processes.

  3. GIS-based probability assessment of natural hazards in forested landscapes of Central and South-Eastern Europe.

    PubMed

    Lorz, C; Fürst, C; Galic, Z; Matijasic, D; Podrazky, V; Potocic, N; Simoncic, P; Strauch, M; Vacik, H; Makeschin, F

    2010-12-01

    We assessed the probability of three major natural hazards--windthrow, drought, and forest fire--for Central and South-Eastern European forests which are major threats for the provision of forest goods and ecosystem services. In addition, we analyzed spatial distribution and implications for a future oriented management of forested landscapes. For estimating the probability of windthrow, we used rooting depth and average wind speed. Probabilities of drought and fire were calculated from climatic and total water balance during growing season. As an approximation to climate change scenarios, we used a simplified approach with a general increase of pET by 20%. Monitoring data from the pan-European forests crown condition program and observed burnt areas and hot spots from the European Forest Fire Information System were used to test the plausibility of probability maps. Regions with high probabilities of natural hazard are identified and management strategies to minimize probability of natural hazards are discussed. We suggest future research should focus on (i) estimating probabilities using process based models (including sensitivity analysis), (ii) defining probability in terms of economic loss, (iii) including biotic hazards, (iv) using more detailed data sets on natural hazards, forest inventories and climate change scenarios, and (v) developing a framework of adaptive risk management. PMID:20535611

  4. GIS-based Probability Assessment of Natural Hazards in Forested Landscapes of Central and South-Eastern Europe

    NASA Astrophysics Data System (ADS)

    Lorz, C.; Fürst, C.; Galic, Z.; Matijasic, D.; Podrazky, V.; Potocic, N.; Simoncic, P.; Strauch, M.; Vacik, H.; Makeschin, F.

    2010-12-01

    We assessed the probability of three major natural hazards—windthrow, drought, and forest fire—for Central and South-Eastern European forests which are major threats for the provision of forest goods and ecosystem services. In addition, we analyzed spatial distribution and implications for a future oriented management of forested landscapes. For estimating the probability of windthrow, we used rooting depth and average wind speed. Probabilities of drought and fire were calculated from climatic and total water balance during growing season. As an approximation to climate change scenarios, we used a simplified approach with a general increase of pET by 20%. Monitoring data from the pan-European forests crown condition program and observed burnt areas and hot spots from the European Forest Fire Information System were used to test the plausibility of probability maps. Regions with high probabilities of natural hazard are identified and management strategies to minimize probability of natural hazards are discussed. We suggest future research should focus on (i) estimating probabilities using process based models (including sensitivity analysis), (ii) defining probability in terms of economic loss, (iii) including biotic hazards, (iv) using more detailed data sets on natural hazards, forest inventories and climate change scenarios, and (v) developing a framework of adaptive risk management.

  5. A parameter-free community detection method based on centrality and dispersion of nodes in complex networks

    NASA Astrophysics Data System (ADS)

    Li, Yafang; Jia, Caiyan; Yu, Jian

    2015-11-01

    K-means is a simple and efficient clustering algorithm to detect communities in networks. However, it may suffer from a bad choice of initial seeds (also called centers) that seriously affect the clustering accuracy and the convergence rate. Additionally, in K-means, the number of communities should be specified in advance. Till now, it is still an open problem on how to select initial seeds and how to determine the number of communities. In this study, a new parameter-free community detection method (named K-rank-D) was proposed. First, based on the fact that good initial seeds usually have high importance and are dispersedly located in a network, we proposed a modified PageRank centrality to evaluate the importance of a node, and drew a decision graph to depict the importance and the dispersion of nodes. Then, the initial seeds and the number of communities were selected from the decision graph actively and intuitively as the 'start' parameter of K-means. Experimental results on synthetic and real-world networks demonstrate the superior performance of our approach over competing methods for community detection.

  6. A MODIS- Based Approach for Crop Yield Prediction in Irrigation Regions of Central Asia Using Light Use Efficiency Modeling

    NASA Astrophysics Data System (ADS)

    Fritsch, Sebastian; Conrad, Christopher, Dech, Stefan

    2010-12-01

    This study describes a MODIS-driven light-use efficiency (LUE) model for irrigated agriculture in a test area of arid Central Asia where there is a high demand for solutions to widespread environmental and economic problems. The model was applied to cotton, winter-wheat and rice and is based on MODIS FPAR time-series, crop maps, meteorological data (temperature, relative humidity, PAR) and crop-specific parameters (growing season, maximum LUE and harvest index). To increase spatial accuracy the MODIS FPAR product was downscaled from 1km to 250m by applying crop-specific linear regressions between NDVI and FPAR. Actual crop production was derived via temperature and water stress terms calculated from meteorological data. Results were compared to official statistics for accuracy assessment. They indicate that the model overestimates crop yields on the regional scale, which is due to scaling issues caused by MODIS data. It is shown that the incorporation of sub-pixel information can account for this drawback.

  7. Determinants of Cervical Cancer Screening Uptake among Women in Ilorin, North Central Nigeria: A Community-Based Study

    PubMed Central

    Idowu, Ajibola; Olowookere, Samuel Anu; Fagbemi, Aderonke Tolulope; Ogunlaja, Olumuyiwa Ayotunde

    2016-01-01

    Introduction. Cancer of the cervix is the leading cause of cancer deaths among women in developing countries. Screening is one of the most cost effective control strategies for the disease. This study assessed the determinants of cervical cancer screening uptake among Nigerian women. Methodology. This cross-sectional study was conducted using multistage sampling technique among 338 participants in Ilorin, North Central Nigeria. A pretested questionnaire was used for data collection and data analysis was done using SPSS version 21. Chi-square test was used for bivariate analysis while binary logistic regression was used for multivariate analysis. Statistical significance was set at p < 0.05. Results. Only 8.0% of the respondents had ever been screened for cancer of the cervix. The proportion of women who had ever been screened was significantly higher among those who demonstrated positive attitude to screening (81.5%, p = 0.001), respondents who were aware of the disease (100.0%, p = 0.001), and those who were aware of cervical cancer screening (88.9%, p = 0.001). Respondents who had negative attitude had 63% lesser odds of being screened compared to those who had positive attitudes towards screening (AOR; 0.37, 95% CI; 0.01–0.28). Conclusion. There is urgent need to improve the knowledge base and attitude of Nigerian women to enhance cervical cancer screening uptake among them. PMID:26880916

  8. Enhancing flavonoid production by systematically tuning the central metabolic pathways based on a CRISPR interference system in Escherichia coli

    PubMed Central

    Wu, Junjun; Du, Guocheng; Chen, Jian; Zhou, Jingwen

    2015-01-01

    The limited supply of intracellular malonyl-CoA in Escherichia coli impedes the biological synthesis of polyketides, flavonoids and biofuels. Here, a clustered regularly interspaced short palindromic repeats (CRISPR) interference system was constructed for fine-tuning central metabolic pathways to efficiently channel carbon flux toward malonyl-CoA. Using synthetic sgRNA to silence candidate genes, genes that could increase the intracellular malonyl-CoA level by over 223% were used as target genes. The efficiencies of repression of these genes were tuned to achieve appropriate levels so that the intracellular malonyl-CoA level was enhanced without significantly altering final biomass accumulation (the final OD600 decreased by less than 10%). Based on the results, multiple gene repressing was successful in approaching the limit of the amount of malonyl-CoA needed to produce the plant-specific secondary metabolite (2S)-naringenin. By coupling the genetic modifications to cell growth, the combined effects of these genetic perturbations increased the final (2S)-naringenin titer to 421.6?mg/L, which was 7.4-fold higher than the control strain. The strategy described here could be used to characterize genes that are essential for cell growth and to develop E. coli as a well-organized cell factory for producing other important products that require malonyl-CoA as a precursor. PMID:26323217

  9. Ocular biometry in the adult population in rural central China: a population-based, cross-sectional study

    PubMed Central

    Fu, Ting; Song, Yin-Wei; Chen, Zhi-Qi; He, Jun-Wen; Qiao, Kun; Sun, Xu-Fang; Zhang, Hong; Wang, Jun-Ming

    2015-01-01

    AIM To describe the distribution and determinants of ocular biometric parameters and to ascertain the relative importance of these determinants in a large population of adults in rural central China. METHODS A population-based, cross-sectional study performed in rural central China included 1721 participants aged 40 or more years. Ocular biometrical parameters including axial length (AL), anterior chamber depth (ACD), radius of corneal curvature (K) and horizontal corneal diameter [white-to-white (WTW) distance] were measured using non-contact partial coherence interferometry [intraocular lens (IOL)-Master]. RESULTS Ocular biometric data on 1721 participants with a average age of 57.0±8.7y were analyzed at last. The general mean AL, ACD, mean corneal curvature radius (MCR), WTW were 22.80±1.12, 2.96±0.36, 7.56±0.26 and 11.75±0.40 mm, respectively. The mean values of each parameter in 40 to 49, 50 to 59, 60 to 69, and 70 to 91 years age groups were as follows: AL, 22.77±0.87, 22.76±1.06, 22.89±1.41, 22.92±0.80 mm; ACD, 3.10±0.32, 2.98±0.34, 2.86±0.36, 2.77±0.35 mm; MCR, 7.58±0.25, 7.54±0.26, 7.55±0.26, 7.49±0.28 mm; WTW, 11.79±0.38, 11.75±0.40, 11.72±0.41, 11.67±0.41 mm. The AL, ACD, MCR and WTW were correlated with age and the AL was correlated with height and weight. CONCLUSION Our findings can serve as an important normative reference for multiple purposes and may help to improve the quality of rural eye care. PMID:26309884

  10. Tree-ring-width-based PDSI reconstruction for central Inner Mongolia, China over the past 333 years

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Zhang, Xinjia; Song, Huiming; Cai, Qiufang; Li, Qiang; Zhao, Boyang; Liu, Han; Mei, Ruochen

    2016-04-01

    A tree-ring-width chronology was developed from Pinus tabulaeformis aged up to 333 years from central Inner Mongolia, China. The chronology was significantly correlated with the local Palmer Drought Severity Index (PDSI). We therefore reconstructed the first PDSI reconstruction from March to June based on the local tree ring data from 1680 to 2012 AD. The reconstruction explained 40.7 % of the variance (39.7 % after adjusted the degrees of freedom) of the actual PDSI during the calibration period (1951-2012 AD). The reconstructed PDSI series captured the severe drought event of the late 1920s, which occurred extensively in northern China. Running variance analyses indicated that the variability of drought increased sharply after 1960, indicating more drought years, which may imply anthropogenic related global warming effects in the region. In the entire reconstruction, there were five dry periods: 1730-1814 AD, 1849-1869 AD, 1886-1942 AD (including severe drought in late 1920s), 1963-1978 AD and 2004-2007 AD; and five wet periods: 1685-1729 AD, 1815-1848 AD, 1870-1885 AD, 1943-1962 AD and 1979-2003 AD. Conditions turned dry after 2003 AD, and the PDSI from March to June (PDSI36) captured many interannual extreme drought events since then, such as 2005-2008 AD. The reconstruction is comparable to other tree-ring-width-based PDSI series from the neighboring regions, indicating that our reconstruction has good regional representativeness. Significant relationships were found between our PDSI reconstruction and the solar radiation cycle and the sun spot cycle, North Atlantic Oscillation, the El Niño-Southern Oscillation, as well as the Pacific Decadal Oscillation. Power spectral analyses detected 147.0-, 128.2-, 46.5-, 6.5-, 6.3-, 2.6-, 2.2- and 2.0-year quasi-cycles in the reconstructed series.

  11. A GIS-based Spatial Analysis of Volcanoes in the Central Andes: Insights Into Factors Controlling Volcano Spacing.

    NASA Astrophysics Data System (ADS)

    Savant, S. S.; de Silva, S. L.

    2005-12-01

    Volcano spacing has received little attention since the mid-70's when studies undertaken by Vogt (1974; EPSL) and then Marsh (1979; J Geol) suggested a regular spacing of volcanoes in arcs that ranged from 50 to 75 km for different arcs. The spacing was thought to be influenced by the thickness of the lithosphere or gravitational (Rayleigh-Taylor) instabilities related to source layer thickness and viscosity respectively. We have revisited these ideas through a detailed study of volcano distribution in the Central Volcanic Zone (CVZ) of the Andes where volcano spacing was thought to be around 70 km. The CVZ was selected as it is the type example of continental arc volcanism, built on an extremely thick crust of up to 70 km. The availability of a comprehensive dataset describing the relative age, location, and geomorphic characteristics of each volcano (Volcanoes of the Central Andes, de Silva and Francis, 1990, Springer Verlag) made this a compelling case study. The ready availability of ARC GIS Geographic Information Systems software and the geospatial analysis tools therein, allowed a comprehensive spatial analysis of the volcanoes to be conducted. Of the 1,118 volcanoes of ages from 23Ma to active in the CVZ, we focused on the 106 active and potentially active large composite volcanoes that define the modern arc. These volcanoes are related in time and thus to a consistent set of tectonic factors. The frequency distribution of inter-volcano distances shows a peak frequency in the 10 - 30 km range (71%) with subordinate between 40-80 km (19%) and 80 - 120 km (10%). The characteristic spacing is thus much smaller than the characteristic spacing of 70 km found previously and is consistent with Baker (1974; EPSL). The primary cause appears to be clustering of volcanoes into groups. The density of volcanoes is variable along the arc with regularly spaced clusters of two to three volcanoes in northern and southern parts of the arc (13 r°S to 19 r°S and 24 r° to 27 r°S). The central part of the arc between 22 r° and 24 r°S shows the highest density of volcanoes. An interpolated continuous raster grid of volcano base elevation revealed a strong positive correlation with the density of volcanoes. Interestingly, the spacing of the peaks in density is fairly regular at about 75 to 110 km. We interpret the different orders of spacing as reflecting control by different levels within the plumbing system for the arc. The spacing of density peaks (clusters) is likely the primary spacing of diapirs rising from the source layer into the lithosphere. The dominant 10 to 30 km spacing of individual volcanoes probably reflects the influence of intra-crustal regions superimposed on the primary spacing. These regions may be mid-crustal, low-velocity, high-conductivity zones that have been imaged geophysically and/or the influence of older upper crustal batholiths that may have been emplaced into the thickest crust between 22 r° and 24 r°S.

  12. Treatment of Dens Invagination in a Maxillary Lateral Incisor: A Case Report

    PubMed Central

    Heydari, Azar; Rahmani, Mona

    2015-01-01

    Dens invagination is a developmental anomaly requiring specific treatment approaches. Oehler's Type III dens in dente, extends into the root and perforates at the apical area or lateral surface of the root. In this case endodontic treatment of the invaginated tooth was carried out through the central lumen of the invagination with calcium hydroxide without manipulation of the main pulp canal, thereby leaving the tooth vital. The 18-month follow-up examinations were indicative of treatment success; the periapical lesion resolved completely and the tooth remained vital. Conclusion: Information about the three dimensional anatomy of the teeth especially those with an abnormality is necessary for a successful treatment. PMID:26213545

  13. A three-dimensional slope stability model based on GRASS GIS and its application to the Collazzone area, Central Italy

    NASA Astrophysics Data System (ADS)

    Mergili, M.; Marchesini, I.; Fellin, W.; Rossi, M.; Raia, S.; Guzzetti, F.

    2012-04-01

    Landslide risk depends on landslide hazard, i.e. the probability of occurrence of a slope failure of a given magnitude within a specified period and in a given area. The occurrence probability of slope failures in an area characterized by a set of geo-environmental parameters gives the landslide susceptibility. Statistical and deterministic methods are used to assess landslide susceptibility. Deterministic models based on limit equilibrium techniques are applied for the analysis of particular types of landslides (e.g., shallow soil slips, debris flows, rock falls), or to investigate the effects of specific triggers, i.e., an intense rainfall event or an earthquake. In particular, infinite slope stability models are used to calculate the spatial probability of shallow slope failures. In these models, the factor of safety is computed on a pixel basis, assuming a slope-parallel, infinite slip surface. Since shallow slope failures coexist locally with deep-seated landslides, infinite slope stability models fail to describe the complexity of the landslide phenomena. Limit equilibrium models with curved sliding surfaces are geometrically more complex, and their implementation with raster-based GIS is a challenging task. Only few attempts were made to develop GIS-based three-dimensional applications of such methods. We present a preliminary implementation of a GIS-based, three-dimensional slope stability model capable of dealing with deep-seated and shallow rotational slope failures. The model is implemented as a raster module (r.rotstab) in the Open Source GIS package GRASS GIS, and makes use of the three-dimensional sliding surface model proposed by Hovland (1977). Given a DEM and a set of thematic layers of geotechnical and hydraulic parameters, the model tests a large number of randomly determined potential ellipsoidal slip surfaces. In addition to ellipsoidal slip surfaces, truncated ellipsoids are tested, which can occur in the presence of weak layers or hard bedrock. Any raster cell may be intersected by various sliding surfaces, each associated with a computed factor of safety. The lowest value of the factor of safety is stored for each raster cell together with the depth of the associated slip surface. This results in an overview of potentially unstable regions without showing the individual sliding areas. We test the model in the Collazzone area, Umbria, Central Italy, which is susceptible to landslides of different types. The presence of both shallow translational and deep-seated rotational landslides, and the availability of reference data, allow for the critical evaluation of the model in comparison with standard infinite slope stability models.

  14. Localization of transcriptional co-activator CBP in the ameloblasts and the other enamel organ-derived cells of the rat incisor.

    PubMed

    Nishikawa, Sumio

    2002-11-01

    CREB-binding protein (CBP) was examined in ameloblasts and in other enamel organ-derived cells of the rat incisor, using Western blotting analysis and immunocytochemistry by specific antibodies. Western blotting of labial tissues, including ameloblasts of the incisors, detected a single band with a molecular weight equivalent to the reported value of CBP. In immunocytochemistry, CBP was localized in ameloblast nuclei in the maturation zone but not in the secretion and transition zones. The nuclei of the other enamel organ-derived cells were also positive. Because this protein is suggested to take part in c-Jun-mediated transcription, the present study and the results of a previous report showing c-Jun localization in the nuclei of enamel organ-derived cells suggest that the enamel organ-derived cells, including maturation ameloblasts, undergo active transcriptional regulation. PMID:12417610

  15. Central Odontogenic Fibroma of the Gingiva: A Case Report

    PubMed Central

    Soolari, Ahmad; Khan, Asghar

    2015-01-01

    In this paper, we present a case of an uncommon and slow-growing tumor known as a central odontogenic fibroma (COF). The patient in question is a 53-year-old African-American man who was referred for periodontal evaluation of asymptomatic space formation between the mandibular central incisors. Clinical and radiological evaluations disclosed tumor-like tissue expanding the alveolar ridge in the buccolingual dimension, along with thinning of the cortical plates. Surgical excision was performed, and the specimen was sent for histopathology, which later confirmed that the lesion was a COF. Periodontal regenerative therapy was performed to rebuild the hard and soft tissue that had been compromised as a result of tumor expansion. The site was grafted, with excellent results. PMID:25646136

  16. Mapping hydrological environments in central Amazonia: ground validation and surface model based on SRTM DEM data corrected for deforestation

    NASA Astrophysics Data System (ADS)

    Moulatlet, G. M.; Rennó, C. D.; Costa, F. R. C.; Emilio, T.; Schietti, J.

    2015-03-01

    One of the most important freely available digital elevation models (DEMs) for Amazonia is the one obtained by the Shuttle Radar Topography Mission (SRTM). However, since SRTM tends to represent the vegetation surface instead of the ground surface, the broad use of SRTM DEM as a framework for terrain description in Amazonia is hampered by the presence of deforested areas. We present here two data sets: (1) a deforestation-corrected SRTM DEM for the interfluve between the Purus and Madeira rivers, in central Amazonia, which passed through a careful identification of different environments and has deforestation features corrected by a new method of increasing pixel values of the DEM (Rennó, 2009); and (2) a set of 18 hydrological-topographic descriptors based on the corrected SRTM DEM. Deforestation features are related with the opening of an 800 km road in the central part of the interfluve and occupancy of its vicinity. We used topographic profiles from the pristine forest to the deforested feature to evaluate the recovery of the original canopy coverage by minimizing canopy height variation (corrections ranged from 1 to 38 m). The hydrological-topographic description was obtained by the Height Above the Nearest Drainage (HAND) algorithm, which normalizes the terrain elevation (above sea level) by the elevation of the nearest hydrologically connected drainage. The validation of the HAND data set was done by in situ hydrological description of 110 km of walking trails also available in this data set. The new SRTM DEM expands the applicability of SRTM data for landscape modelling; the data sets of hydrological features based on topographic modelling are undoubtedly appropriate for ecological modelling and an important contribution to environmental mapping of Amazonia. The deforestation-corrected SRTM DEM is available at http://ppbio.inpa.gov.br/knb/metacat/naman.318.3/ppbio; the polygons selected for deforestation correction are available at http://ppbio.inpa.gov.br/knb/metacat/naman.317.3/ppbio; the set of hydrological-topographic descriptors is available at http://ppbio.inpa.gov.br/knb/metacat/naman.544.2/ppbio; the environmental description of access trails is available at http://ppbio.inpa.gov.br/knb/metacat/naman.541.2/ppbio; and the limits of deforestation corrections and drainage validation are available at http://ppbio.inpa.gov.br/knb/metacat/liliandias.38.1/ppbio.

  17. Causes and prevalence of traumatic injuries to the permanent incisors of school children aged 10-14 years in Maseru, Lesotho.

    PubMed

    Lin, H; Naidoo, Sudeshni

    2008-04-01

    Traumatic dental injuries are widespread in the population and the prevalence of traumatic dental injuries among school children in different parts of the world varies from about 3% to 45%. Most injuries involve the anterior teeth, which may lead to eating restrictions, changes in physical appearance, speech defects and psychological impacts that affect the child's quality of life. A cross-sectional survey was carried out to investigate the prevalence, aetiology and types of injuries to permanent incisors among schoolchildren aged 10-14 years from Maseru, Lesotho. Upper and lower permanent incisors were examined for dental injuries. The prevalence of traumatic injuries to the permanent incisor teeth was 9.3% (13.3% boys and 6.3% girls). Significantly more boys than girls suffered injury. The most common type of injury was enamel fractures and most common cause was falls. Health promotion policies should aim to create an appropriate and safe environment for children. Soft playground surfaces, school-crossing patrols, marked zebra crossings and bicycle lanes would help create a safe environment. Speed limits for cars and the use of seat belts, air bags, special car seats for children and bicycle helmets should be enforced. Mouth guards should be used when playing sport, in particular contact sports. Education regarding the epidemiology of dental injuries and their prevention through health promotion may play a major role in reducing the prevalence of dental injury and avoiding the financial costs of treatment, especially in developing countries. PMID:18689347

  18. Distribution of non-collagenous dentin matrix proteins and proteoglycans, and their relation to calcium accumulation in bisphosphonate-affected rat incisors.

    PubMed

    Ohma, N; Takagi, Y; Takano, Y

    2000-06-01

    It has been reported that multiple injections of 1-hydroxyethylidene- 1,1-bisphosphonate (HEBP) to rats prevent mineralization of incisor dentin, thereby revealing high concentrations of calcium in the non-mineralized matrix of circumpulpal dentin. To identify the molecules responsible for calcium accumulation in circumpulpal dentin matrix, rats were injected daily with HEBP (8 mg P/kg) for 7 d, and the incisors processed for various histochemical and immunohistochemical staining of non-collagenous matrices of dentin. Cuprolinic blue reactions for proteoglycans (PGs) were equally distributed in non-mineralized matrix of mantle and circumpulpal dentin layers. Dentin sialoprotein (DSP) and osteopontin (OPN) immunoreactions were found in non-mineralized circumpulpal dentin matrix, but not in mantle dentin. In normal incisors, however, predentin matrix showing significant DSP immunoreactivity was negative for Ca-GBHA reactions. HEBP-affected, non-mineralized OPN immunopositive bone matrix was also non-reactive for calcium. From these observations, neither PGs, OPN nor DSP appear to be responsible for calcium accumulation in HEBP-affected circumpulpal dentin. Stains-all reactive component, possibly dentin phosphoprotein (DPP), only showed the same distribution as that of Ca-GBHA in both HEBP-affected and normal dentin matrix, implicating a possible contribution of DPP to calcium accumulation in circumpulpal dentin and, hence, to appositional mineralization of dentin. PMID:10872993

  19. The effect of different full-coverage crown systems on fracture resistance and failure pattern of endodontically treated maxillary incisors restored with and without glass fiber posts.

    PubMed

    Salameh, Ziad; Sorrentino, Roberto; Ounsi, Hani F; Sadig, Walid; Atiyeh, Fadi; Ferrari, Marco

    2008-07-01

    The aim of this study was to compare the fracture resistance and failure pattern of endodontically treated maxillary incisors restored using composite resin with or without fiber-reinforced composite (FRC) posts under different types of full-coverage crowns. The null hypothesis tested was that fracture resistance and the failure pattern of these teeth were not affected by the use of FRC posts or by the type of full-coverage crown. One hundred twenty maxillary incisors were endodontically treated and divided into 4 groups of 30 each. Each group was divided into two subgroups: restoration with or without fiber post. PFM crowns were placed in group 1, Empress II crowns in group 2, SR Adoro crowns in group 3, and Cercon crowns in group 4. Fracture tests were performed by loading specimens to fracture. Data were analyzed with two-way analysis of variance (alpha = 0.05). The type of crown was not a significant factor affecting fracture resistance (p = 0.4), whereas the presence of a post was (p = 0.001). Both the presence of post and the type of crown had a significant influence on the proportion of restorable versus unrestorable fractures. Although prosthodontics textbooks do not generally advocate the placement of fiber posts in endodontically treated incisors, the results of this study indicate that the use of fiber posts in such teeth increases their resistance to fracture and improves the prognosis in case of fracture. PMID:18570992

  20. Field based measurements of albedo for two candidate perennial cellulosic feedstocks and row crops in Central Illinois

    NASA Astrophysics Data System (ADS)

    Miller, J. N.; VanLoocke, A.; Bernacchi, C. J.

    2012-12-01

    The production of perennial cellulosic feedstocks for bioenergy present the potential to diversify regional economies and the national energy supply, while also serving as a climate 'regulators' due to a number of biogeochemical and biophysical differences relative to row crops. Numerous observationally and modeling based approaches, including life cycle analyses have investigated biogeochemical tradeoffs, such as increased carbon sequestration and biophysical increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biophysical changes associated with the difference in albedo, which will alter the local energy balance and could cause a local to regional cooling several times larger than that associated with offsetting carbon. To address this factor an experiment consisting of paired fields of Miscanthus and Switchgrass, two of the leading perennial cellulosic feedstock candidates, and traditional row crops was established in central Illinois. Data from the first two growing seasons indicate that this effect is most pronounced during the spring and fall as perennial biofuel crops green up earlier and senesce later than common annual row crops. The albedo of the perennials converges to that of the row crops during the growing season as the canopies develop. During the early winter, before the perennial crops are harvested, the albedo over fallow soybean and maize fields can vary greatly depending on snowfall and, to a lesser extent, soil moisture, whereas perennials show less variation. Thus, perennial biofuel crops also have the potential to buffer the local environment against short-term variations in climate. These factors should be considered when evaluating the tradeoffs and climate-regulation services associated with large-scale planting of bioenergy crops.

  1. Structure-based functional characterization of repressor of toxin (Rot), a central regulator of staphylococcus aureus virulence

    DOE PAGESBeta

    Killikelly, April; Jakoncic, Jean; Benson, Meredith A.; Ohneck, Elizabeth A.; Sampson, Jared M.; Spurrier, Brett; Torres, Victoer J.; Kong, Xian -Peng

    2014-10-20

    Staphylococcus aureus is responsible for a large number of diverse infections worldwide. In order to support its pathogenic lifestyle, S. aureus has to regulate the expression of virulence factors in a coordinated fashion. One of the central regulators of the S. aureus virulence regulatory networks is the transcription factor repressor of toxin (Rot). Rot plays a key role in regulating S. aureus virulence through activation or repression of promoters that control expression of a large number of critical virulence factors. However, the mechanism by which Rot mediates gene regulation has remained elusive. Here, we have determined the crystal structure ofmore » Rot and used this information to probe the contribution made by specific residues to Rot function. Rot was found to form a dimer, with each monomer harboring a winged helix-turn-helix (WHTH) DNA-binding motif. Despite an overall acidic pI, the asymmetric electrostatic charge profile suggests that Rot can orient the WHTH domain to bind DNA. Structure-based site-directed mutagenesis studies demonstrated that R91, at the tip of the wing, plays an important role in DNA binding, likely through interaction with the minor groove. We also found that Y66, predicted to bind within the major groove, contributes to Rot interaction with target promoters. Evaluation of Rot binding to different activated and repressed promoters revealed that certain mutations on Rot exhibit promoter-specific effects, suggesting for the first time that Rot differentially interacts with target promoters. As a result, this work provides insight into a precise mechanism by which Rot controls virulence factor regulation in S. aureus.« less

  2. Modelling soil moisture spatial-temporal variability with 3-D physically-based hdrological model in central Italy

    NASA Astrophysics Data System (ADS)

    Formetta, Giuseppe; Brocca, Luca; Camici, Stefania; Capparelli, Giovanna; Rigon, Riccardo

    2015-04-01

    Soil water content (SWC) evolution in space and in time influences many hydrological processes such as infiltration and run-off production, surface energy exchanges, floods and drought generation and propagation, triggering of shallow landslide. Modeling SWC is a complex task influenced by heterogeneity in precipitation, soil parameters, topography, and vegetation. In order to consider these different factors we used a three-dimensional process based hydrological model that solves the 3-D Richard equations, coupled with atmospheric energy exchanges, considering the radiative and turbulent fluxes. For the purposes of this study we modeled the surface SWC dynamics (of top 10-15 cm of soil) in a 60 km² watershed located in central Italy (Vallaccia catchment). In the basin were available: i) SWC measured continuously at hourly time step for 3-years (2002-2005), and ii) 35 daily SWC measures carried out within one year (from Nov-2006 to Nov-2007) in seven different fields consisting in a regular grid configuration of five by six nodes (grid-step of 10 m). Two were the objectives of the study. Firstly, the calibration of model parameters (hydraulic conductivity and van Genuchten parameters) in order to simulate long term SWC dynamics in time. The two long-term SWC time-series were split in two and used for model calibration and verification, respectively. Model performances reaches values of Kling-Gupta Efficiency of 0.85 in calibration and 0.78 in verification period, giving confidence of reliability for the estimation of the ungauged points. The second objective was the reproduction of SWC patterns in space in the seven different fields where measurements were collected. For each field, modeled and measured statistical moments (from the first to the fourth: mean, variance, skewness and kurtosis) were presented in the form of scatterplots and influence of the variability of the hydraulic conductivity in space on the overall SWC distribution was investigated by generation of different random-fields correlated in space.

  3. Infection risk factors associated with seropositivity for Toxoplasma gondii in a population-based study in the Central Region, Ghana.

    PubMed

    Abu, E K; Boampong, J N; Ayi, I; Ghartey-Kwansah, G; Afoakwah, R; Nsiah, P; Blay, E

    2015-07-01

    About 20-90% of the world's population has had contact with Toxoplasma gondii parasites. The aim of this study was to determine the seroprevalence and risk factors associated with T. gondii infection in the Central Region, Ghana. A community-based cross-sectional study was conducted in three selected communities. Serum samples were tested for the presence of anti-T. gondii IgG and IgM antibodies by ELISA. A serological criterion for seropositivity was a positive test result for any of the two anti-Toxoplasma IgG or IgM antibodies or a combination of both. In all, 390 participants of mean age 47.0 years consisting of 118 (30.%) males and 272 (69.7%) females were tested. The overall seroprevalence of T. gondii was 85% (333/390) where fishermen, farmers and fishmongers, respectively, had the highest seropositivity. IgG and IgM antibodies were detected in 329 (84%) and 25 (6%), respectively, while both IgG and IgM antibodies were detected in 21 (5%) of the participants. Respectively, 1% (4/390) and 79% (308/390) of participants tested positive for IgM-only and IgG-only antibodies. There was a significant relationship between Toxoplasma seropositivity and contact with soil, presence of a cat in the surrounding area, age, sources of drinking water, level of formal education, and socioeconomic status. The results suggest that the seashore may serve as a good ground for sporulation and survival of Toxoplasma oocysts. PMID:25373611

  4. Feasibility study of date (Phoenix dactylifera L.) fruit syrup-based natural jelly using central composite design.

    PubMed

    Benali, Sonia; Benamara, Salem; Bigan, Muriel; Madani, Khodir

    2015-08-01

    A feasibility study of natural fruit jelly from three Algerian raw materials, namely date (Phoenix dactylifera l.) fruit syrup and suspension of orange albedo powder (OAP) in lemon juice (LJ) was performed by response surface methodology (RSM) based on central composite design (CCD). The textural properties of the final jelly were investigated through two dependent variables: hardness and stickiness. The cooking temperature (X1), corresponding to that of thermo stated oil bath, and cooking time (X 2), taken for heating the initial fruit mixture in the oil bath (from ambient temperature without fixing however, the final temperature), were found to be the most influent factors, compared to °Brix of date syrup (X3) and temperature (X4) of the cooling stage following the cooking process. Results have also shown that the second-degree polynomial models correctly fit experimental data (R(2), adjusted R(2) (R(2) adj) and cross-validation (Q(2)) ≈ 1). Considering textural properties of commercial jellies as a reference, it was found that the cooking temperature of 155 °C for 10 min gave a jelly with suitable textural properties. On the other hand, FT-IR spectra revealed that the structure of such jelly was partially close to that of pectin molecules. Finally, the color analysis in the CIELab system of the fruit mixture over the cooking process showed that both lightness (L(*)) and a*/b* ratio were not affected by the experienced temperature range (80-155 °C). PMID:26243917

  5. Structure-Based Functional Characterization of Repressor of Toxin (Rot), a Central Regulator of Staphylococcus aureus Virulence

    PubMed Central

    Killikelly, April; Benson, Meredith A.; Ohneck, Elizabeth A.; Sampson, Jared M.; Jakoncic, Jean; Spurrier, Brett

    2014-01-01

    Staphylococcus aureus is responsible for a large number of diverse infections worldwide. In order to support its pathogenic lifestyle, S. aureus has to regulate the expression of virulence factors in a coordinated fashion. One of the central regulators of the S. aureus virulence regulatory networks is the transcription factor repressor of toxin (Rot). Rot plays a key role in regulating S. aureus virulence through activation or repression of promoters that control expression of a large number of critical virulence factors. However, the mechanism by which Rot mediates gene regulation has remained elusive. Here, we have determined the crystal structure of Rot and used this information to probe the contribution made by specific residues to Rot function. Rot was found to form a dimer, with each monomer harboring a winged helix-turn-helix (WHTH) DNA-binding motif. Despite an overall acidic pI, the asymmetric electrostatic charge profile suggests that Rot can orient the WHTH domain to bind DNA. Structure-based site-directed mutagenesis studies demonstrated that R91, at the tip of the wing, plays an important role in DNA binding, likely through interaction with the minor groove. We also found that Y66, predicted to bind within the major groove, contributes to Rot interaction with target promoters. Evaluation of Rot binding to different activated and repressed promoters revealed that certain mutations on Rot exhibit promoter-specific effects, suggesting for the first time that Rot differentially interacts with target promoters. This work provides insight into a precise mechanism by which Rot controls virulence factor regulation in S. aureus. PMID:25331435

  6. Reinterpretation of Paleoproterozoic accretionary boundaries of the north-central United States based on a new aeromagnetic-geologic compilation

    USGS Publications Warehouse

    Holm, D.K.; Anderson, R.; Boerboom, Timothy; Cannon, W.F.; Chandler, V.; Jirsa, M.; Miller, J.; Schneider, D.A.; Schulz, K.J.; Van Schmus, W. R.

    2007-01-01

    The Paleoproterozoic crust in the north-central U.S. represents intact juvenile terranes accreted to the rifted Archean Superior craton. A new tectonic province map, based on the interpretation of a new aeromagnetic compilation, published geologic maps, and recent geochronologic data, shows progressive accretion of juvenile arc terranes from ca. 1900-1600 Ma. Contrary to earlier models, geon 18 Penokean-interval crust is primarily confined to a ???2100 Ma tectonic embayment of the rifted Superior craton. The newly defined Spirit Lake tectonic zone, characterized by a sharp magnetic discontinuity that marks the southern limit of Archean and Penokean-interval rocks, is here interpreted to represent an eastern analog of the Cheyenne belt suture zone in southern Wyoming. South of this boundary, geon 17 Yavapai-interval rocks form the basement upon which 1750 Ma rhyolite and succeeding quartzite sequences were deposited. Substantial portions of the Penokean and Yavapai terranes were subsequently deformed during the 1650-1630 Ma Mazatzal orogeny. The northern boundary of the Mazatzal terrane is obscured by abundant 1470-1430 Ma "anorogenic" plutons that stitched the suture with the older Yavapai terrane rocks. These data reveal a progressive tectonic younging to the south as the Laurentian craton grew southward and stabilized during the Proterozoic. Late Mesoproterozoic rift magmatism produced pronounced geophysical anomalies, indicating strong, but localized crustal modification. In comparison to the western U.S., little tectonism has occurred here in the last 1 billion years, providing a uniquely preserved record of the Precambrian evolution of the continental U.S. lithosphere. ?? 2007 Elsevier B.V. All rights reserved.

  7. Detection of planets in extremely weak central perturbation microlensing events via next-generation ground-based surveys

    SciTech Connect

    Chung, Sun-Ju; Lee, Chung-Uk; Koo, Jae-Rim E-mail: leecu@kasi.re.kr

    2014-04-20

    Even though the recently discovered high-magnification event MOA-2010-BLG-311 had complete coverage over its peak, confident planet detection did not happen due to extremely weak central perturbations (EWCPs, fractional deviations of ≲ 2%). For confident detection of planets in EWCP events, it is necessary to have both high cadence monitoring and high photometric accuracy better than those of current follow-up observation systems. The next-generation ground-based observation project, Korea Microlensing Telescope Network (KMTNet), satisfies these conditions. We estimate the probability of occurrence of EWCP events with fractional deviations of ≤2% in high-magnification events and the efficiency of detecting planets in the EWCP events using the KMTNet. From this study, we find that the EWCP events occur with a frequency of >50% in the case of ≲ 100 M {sub E} planets with separations of 0.2 AU ≲ d ≲ 20 AU. We find that for main-sequence and sub-giant source stars, ≳ 1 M {sub E} planets in EWCP events with deviations ≤2% can be detected with frequency >50% in a certain range that changes with the planet mass. However, it is difficult to detect planets in EWCP events of bright stars like giant stars because it is easy for KMTNet to be saturated around the peak of the events because of its constant exposure time. EWCP events are caused by close, intermediate, and wide planetary systems with low-mass planets and close and wide planetary systems with massive planets. Therefore, we expect that a much greater variety of planetary systems than those already detected, which are mostly intermediate planetary systems, regardless of the planet mass, will be significantly detected in the near future.

  8. The Lilongwe Central Hospital Patient Management Information System: A Success in Computer-Based Order Entry Where One Might Least Expect It

    PubMed Central

    GP, Douglas; RA, Deula; SE, Connor

    2003-01-01

    Computer-based order entry is a powerful tool for enhancing patient care. A pilot project in the pediatric department of the Lilongwe Central Hospital (LCH) in Malawi, Africa has demonstrated that computer-based order entry (COE): 1) can be successfully deployed and adopted in resource-poor settings, 2) can be built, deployed and sustained at relatively low cost and with local resources, and 3) has a greater potential to improve patient care in developing than in developed countries. PMID:14728338

  9. Effect of intermediate fiber layer on the fracture load and failure mode of maxillary incisors restored with laminate veneers.

    PubMed

    Turkaslan, Suha; Tezvergil-Mutluay, Arzu; Bagis, Bora; Shinya, Akikazu; Vallittu, Pekka K; Lassila, Lippo V

    2008-01-01

    This study evaluated the fracture load and failure mode of various veneer materials cemented with or without the addition of a fiber-reinforced composite (FRC) layer at the adhesive interface. Sixty intact incisors were randomly divided into three groups. Group 1 was fabricated with the heat-press technique (IPS Empress 2); Group 2 with the copy milling technique (ZirkonZahn); and Group 3 with the direct or indirect composite technique (Z250)--and specimens were cemented either with or without FRC at the adhesive interface. The specimens were thermocycled and tested with a universal testing machine. No significant differences in fracture load (p>0.05) were found among the various veneer materials. The addition of FRC at the adhesive layer did not lead to significant differences in the fracture load (p>0.05) but resulted in differences in the failure mode. Laminate veneers made of composite, zirconia, and Empress 2 showed comparable mean fracture loads. However, the use of FRC at the interface changed their failure modes. PMID:18309613

  10. Accuracy of CBCT, Digital Radiography and Cross-Sectioning for the Evaluation of Mandibular Incisor Root Canals

    PubMed Central

    Assadian, Hadi; Dabbaghi, Arash; Gooran, Morteza; Eftekhar, Behrouz; Sharifi, Sanaz; Shams, Nassim; Dehghani Najvani, Ali; Tabesh, Hamed

    2016-01-01

    Introduction: The aim of this study was to compare the accuracy of cone-beam computed tomography (CBCT), digital radiography and tooth sectioning in evaluating root canal morphology of mandibular incisors in an in vitro setting. Methods and Materials: A total of 76 samples were imaged using CBCT, and digital radiography in straight and angled views. The samples were then sectioned at different distances from the apex for further visualization under stereomicroscope. The agreement between the observers was statistically analyzed by kappa correlation coefficient and the chi-square test. Results: The results showed that the majority of the samples had a single canal (Vertucci’s Type I). CBCT analysis reported more frequent multi-canal roots in comparison with the other techniques. In pairwise comparisons, the highest agreement was found between digital radiographic imaging and microscopic cross-sectioning both in terms of canal configuration and the number of root canals. Conclusion: None of the used imaging techniques per se could adequately show the exact internal anatomical configuration in accordance with the gold standard. PMID:27141217

  11. Localization of Core Planar Cell Polarity Proteins, PRICKLEs, in Ameloblasts of Rat Incisors: Possible Regulation of Enamel Rod Decussation

    PubMed Central

    Nishikawa, Sumio; Kawamoto, Tadafumi

    2015-01-01

    To confirm the possible involvement of planar cell polarity proteins in odontogenesis, one group of core proteins, PRICKLE1, PRICKLE2, PRICKLE3, and PRICKLE4, was examined in enamel epithelial cells and ameloblasts by immunofluorescence microscopy. PRICKLE1 and PRICKLE2 showed similar localization in the proliferation and secretory zones of the incisor. Immunoreactive dots and short rods in ameloblasts and stratum intermedium cells were evident in the proliferation to differentiation zone, but in the secretion zone, cytoplasmic dots decreased and the distal terminal web was positive for PRICKLE1 and PRICKLE2. PRICKLE3 and PRICKLE4 showed cytoplasmic labeling in ameloblasts and other enamel epithelial cells. Double labeling of PRICKLE2 with VANGL1, which is another planar cell polarity protein, showed partial co-localization. To examine the transport route of PRICKLE proteins, PRICKLE1 localization was examined after injection of a microtubule-disrupting reagent, colchicine, and was compared with CX43, which is a membrane protein transported as vesicles via microtubules. The results confirmed the retention of immunoreactive dots for PRICKLE1 in the cytoplasm of secretory ameloblasts of colchicine-injected animals, but fewer dots were observed in control animals. These results suggest that PRICKLE1 and PRICKLE2 are transported as vesicles to the junctional area, and are involved in pattern formation of distal junctional complexes and terminal webs of ameloblasts, further implying a role in the formed enamel rod arrangement. PMID:26175546

  12. Mapping hydrological environments in central Amazonia: ground validation and surface model based on SRTM DEM data corrected for deforestation

    NASA Astrophysics Data System (ADS)

    Moulatlet, G. M.; Rennó, C. D.; Costa, F. R. C.; Emilio, T.; Schietti, J.

    2014-07-01

    One of the most important freely available digital elevation models (DEMs) for Amazonia is the one obtained by the Shuttle Radar Topography Mission (SRTM). However, since SRTM tends to represent the vegetation surface instead of the ground surface, the broad use of SRTM DEM as a framework for terrain description in Amazonia is hampered by the presence of deforested areas. We present here two datasets: (1) a deforestation-corrected SRTM DEM for the interfluve between the Purus and Madeira rivers, in central Amazonia, which passed through a careful identification of different environments and has deforestation features corrected by a new method of increasing pixel values of the DEM; and (2) a set of eighteen hydrological-topographic descriptors based on the corrected SRTM DEM. The hydrological-topographic description was generated by the Height Above the Nearest Drainage (HAND) algorithm, which normalizes the terrain elevation (a.s.l.) by the elevation of the nearest hydrologically connected drainage. The validation of the HAND dataset was done by in situ hydrological description of 110 km of walking trails also available in this dataset. The new SRTM DEM expands the applicability of SRTM data for landscape modelling; and the datasets of hydrological features based on topographic modelling is undoubtedly appropriate for ecological modelling and an important contribution for environmental mapping of Amazonia. The deforestation-corrected SRTM DEM is available at http://ppbio.inpa.gov.br/knb/metacat/naman.318.3/ppbio; the polygons selected for deforestation correction are available at http://ppbio.inpa.gov.br/knb/metacat/naman.317.3/ppbio; the set of hydrological-topographic descriptors is available at http://ppbio.inpa.gov.br/knb/metacat/naman.544.2/ppbio; and the environmental description of access trails is available at http://ppbio.inpa.gov.br/knb/metacat/naman.541.2/ppbio.

  13. injections based on a 200,000-year record of Plinian eruptions along the Central American Volcanic Arc

    NASA Astrophysics Data System (ADS)

    Metzner, D.; Kutterolf, S.; Toohey, M.; Timmreck, C.; Niemeier, U.; Freundt, A.; Krüger, K.

    2014-10-01

    We present for the first time a self-consistent methodology connecting volcanological field data to global climate model estimates for a regional time series of explosive volcanic events. Using the petrologic method, we estimated SO2 emissions from 36 detected Plinian volcanic eruptions occurring at the Central American Volcanic Arc (CAVA) during the past 200,000 years. Together with simple parametrized relationships collected from past studies, we derive estimates of global maximum volcanic aerosol optical depth (AOD) and radiative forcing (RF) describing the effect of each eruption on radiation reaching the Earth's surface. In parallel, AOD and RF time series for selected CAVA eruptions are simulated with the global aerosol model MAECHAM5-HAM, which shows a relationship between stratospheric SO2 injection and maximum global mean AOD that is linear for smaller volcanic eruptions (<5 Mt SO2) and nonlinear for larger ones (≥5 Mt SO2) and is qualitatively and quantitatively consistent with the relationship used in the simple parametrized approximation. Potential climate impacts of the selected CAVA eruptions are estimated using an earth system model of intermediate complexity by RF time series derived by (1) directly from the global aerosol model and (2) from the simple parametrized approximation assuming a 12-month exponential decay of global AOD. We find that while the maximum AOD and RF values are consistent between the two methods, their temporal evolutions are significantly different. As a result, simulated global maximum temperature anomalies and the duration of the temperature response depend on which RF time series is used, varying between 2 and 3 K and 60 and 90 years for the largest eruption of the CAVA dataset. Comparing the recurrence time of eruptions, based on the CAVA dataset, with the duration of climate impacts, based on the model results, we conclude that cumulative impacts due to successive eruptions are unlikely. The methodology and results presented here can be used to calculate approximate volcanic forcings and potential climate impacts from sulfur emissions, sulfate aerosol or AOD data for any eruption that injects sulfur into the tropical stratosphere.

  14. ScienceCentral: open access full-text archive of scientific journals based on Journal Article Tag Suite regardless of their languages

    PubMed Central

    Huh, Sun

    2013-01-01

    ScienceCentral, a free or open access, full-text archive of scientific journal literature at the Korean Federation of Science and Technology Societies, was under test in September 2013. Since it is a Journal Article Tag Suite-based full text database, extensible markup language files of all languages can be presented, according to Unicode Transformation Format 8-bit encoding. It is comparable to PubMed Central: however, there are two distinct differences. First, its scope comprises all science fields; second, it accepts all language journals. Launching ScienceCentral is the first step for free access or open access academic scientific journals of all languages to leap to the world, including scientific journals from Croatia. PMID:24266292

  15. ScienceCentral: open access full-text archive of scientific journals based on Journal Article Tag Suite regardless of their languages.

    PubMed

    Huh, Sun

    2013-01-01

    ScienceCentral, a free or open access, full-text archive of scientific journal literature at the Korean Federation of Science and Technology Societies, was under test in September 2013. Since it is a Journal Article Tag Suite-based full text database, extensible markup language files of all languages can be presented, according to Unicode Transformation Format 8-bit encoding. It is comparable to PubMed Central: however, there are two distinct differences. First, its scope comprises all science fields; second, it accepts all language journals. Launching ScienceCentral is the first step for free access or open access academic scientific journals of all languages to leap to the world, including scientific journals from Croatia. PMID:24266292

  16. Central line complications

    PubMed Central

    Kornbau, Craig; Lee, Kathryn C; Hughes, Gwendolyn D; Firstenberg, Michael S

    2015-01-01

    Central venous access is a common procedure performed in many clinical settings for a variety of indications. Central lines are not without risk, and there are a multitude of complications that are associated with their placement. Complications can present in an immediate or delayed fashion and vary based on type of central venous access. Significant morbidity and mortality can result from complications related to central venous access. These complications can cause a significant healthcare burden in cost, hospital days, and patient quality of life. Advances in imaging, access technique, and medical devices have reduced and altered the types of complications encountered in clinical practice; but most complications still center around vascular injury, infection, and misplacement. Recognition and management of central line complications is important when caring for patients with vascular access, but prevention is the ultimate goal. This article discusses common and rare complications associated with central venous access, as well as techniques to recognize, manage, and prevent complications. PMID:26557487

  17. Validation and future predictions based on a new Non-Point Source Assessment Toolbox, applied to the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Kourakos, G.; Harter, T.

    2011-12-01

    Groundwater is a major irrigation water source in semi-arid regions. It is also vulnerable to Non-Point Source (NPS) contamination, particularly from nitrate (NO3-) as a result of agricultural practices. To support sound policy decisions we developed a physically based flow and transport model framework to understand and predict the fate of contaminants within regional aquifer systems. In large aquifers, the total source area of pollutants typically cover several thousand square kilometers, whilst individual sources typically do not exceed a few hundred square meters. The large contrast in these scenarios result in NPS modeling tasks that are computationally demanding, and the classical 3D models that solve the Advection-Dispersion Equation (ADE) are often not applicable due to computer memory limitations, numerical dispersion and numerical instabilities. Here, we developed and employed a number of numerical techniques to assemble a Non-Point Source Assessment Toolbox (NPSAT). The NPSAT is a quasi-3D model, combining a flow model and a streamline transport model. The flow model solves the groundwater flow equation using very fine discretization. For very large groundwater basins, a simplistic decomposition method is applied, splitting the aquifer into several overlapping sub-domains and solving to produce a high resolution velocity field. This velocity field is subsequently utilized within the transport model, where backward particle tracking links contamination sources with discharge surfaces using a large number of streamlines. For each streamline the 1D ADE is solved, assuming a unit pulse loading at the source side and a free exit boundary condition at the discharge surface side. From this, a Unit Response Function (URF) is obtained at the discharge surface side. Subsequently, actual Breakthrough Curves (BTCs) can be quickly computed from actual or hypothetical loading histories, by convoluting the URFs with real loading functions. The URFs are stored into a GIS platform and can be used for efficient scenario evaluations without the need to repeat groundwater model simulations. This method is applied to the southern third part of the Central Valley Aquifer, California, which is an intensively farmed semi-arid area, where the local communities rely heavily on groundwater. To obtain a detailed velocity field, the Central Valley Hydrologic Model (CVHM) developed by the USGS was used as the coarse solution, split and refined into a large number of sub-domains. The CVHM resolution is 1 sq mi, with the stresses applied to the center of each cell. In our refined model the well stresses are spatially distributed to a large number of hypothetical wells, where the pumping rates, well depths and screen lengths are obtained from empirical probability distributions, derived from real data. The NPSAT generates a time-dependent water quality probability distribution, which express the time-dependent probability for a discharge surface (e.g., well) to exceed a threshold level of contamination across at a specific time. The model result is compared against real historic nitrate data, and used for future predictions with different scenario evaluations.

  18. Comparative gene expression supports the origin of the incisor and molar process from a single endite in the mandible of the red flour beetle Tribolium castaneum

    PubMed Central

    2013-01-01

    Background The biting edge of the primitive arthropod mandible consists of a biting incisor process and a crushing molar process. These structures are thought to be derived from a structure known as an endite but the precise details of this are not understood. Various hypotheses concerning the number of endites present in the arthropod mandible have been proposed. In the developing embryo, the mandible has an inner and outer lobe that are likely to develop into the incisor and molar processes of the larval mandible; these two lobes are commonly held to be derived from separate endites and to be serially homologous to the galea and lacinia endites of the maxillary appendage respectively (Machida). Results We undertook a study of the development of the embryonic mandible of the beetle Tribolium castaneum using the expression of developmental genes as markers of the developing endites in the mandible and maxilla. The Tribolium ortholog of paired (Tc-prd) has expression domains in the developing maxillary and labial endites as well as the inner and outer lobes of the mandible. Following the expression of Tc-prd in the developing mandible through to late stage embryos shows that the molar and incisor process develop from the inner and outer lobes respectively. In addition to Tc-prd, we compared the expression of genes in the endites of the maxilla to the mandible to draw conclusions about the number of endites in the mandible. Homologs of dachshund are typically expressed in the endites of mandibulate gnathal appendages. Comparison of the expression of Tc-prd, Tribolium dachshund (Tc-dac) and Tribolium wingless (Tc-wg) between the endites of the maxilla and the mandible suggest that, while there are two endites in the maxilla only a single endite is present in the mandible. Conclusions Comparative gene expression suggests that the Tribolium mandible has a single endite from which both mandible lobes are derived. Our results do not support Machida’s hypothesis homologising the incisor and molar processes of the mandible to the galea and lacinia endites of the maxilla. We propose, instead, that both incisor and molar processes are derived from a single endite serially homologous to the lacinia of the maxilla. PMID:23280103

  19. Neuroarchitecture and neuroanatomy of the Drosophila central complex: A GAL4-based dissection of protocerebral bridge neurons and circuits

    PubMed Central

    Wolff, Tanya; Iyer, Nirmala A; Rubin, Gerald M

    2015-01-01

    Insects exhibit an elaborate repertoire of behaviors in response to environmental stimuli. The central complex plays a key role in combining various modalities of sensory information with an insect's internal state and past experience to select appropriate responses. Progress has been made in understanding the broad spectrum of outputs from the central complex neuropils and circuits involved in numerous behaviors. Many resident neurons have also been identified. However, the specific roles of these intricate structures and the functional connections between them remain largely obscure. Significant gains rely on obtaining a comprehensive catalog of the neurons and associated GAL4 lines that arborize within these brain regions, and on mapping neuronal pathways connecting these structures. To this end, small populations of neurons in the Drosophila melanogaster central complex were stochastically labeled using the multicolor flip-out technique and a catalog was created of the neurons, their morphologies, trajectories, relative arrangements, and corresponding GAL4 lines. This report focuses on one structure of the central complex, the protocerebral bridge, and identifies just 17 morphologically distinct cell types that arborize in this structure. This work also provides new insights into the anatomical structure of the four components of the central complex and its accessory neuropils. Most strikingly, we found that the protocerebral bridge contains 18 glomeruli, not 16, as previously believed. Revised wiring diagrams that take into account this updated architectural design are presented. This updated map of the Drosophila central complex will facilitate a deeper behavioral and physiological dissection of this sophisticated set of structures. J. Comp. Neurol. 523:9971037, 2015. 2014 Wiley Periodicals, Inc. PMID:25380328

  20. Focal Image Plane Detection Based on Central Coordinate Point Spectral Value in Off-Axis Digital Particle Holography

    NASA Astrophysics Data System (ADS)

    Qiu, Peizhen; Deng, Lijun; Lu, Wenhui

    2015-12-01

    A method to detect the focal image plane from a single off-axis digital particle hologram is proposed. This method utilizes the central coordinate point spectral value of the reconstructed particle image as focusing criterion to detect the focal image plane. It is found that the central coordinate point spectral values come into maximum when the reconstruction distance is equal to the actual distance that was used in experiment of hologram acquisition. Numerical simulations are given to validate the feasibility and effectiveness of the proposed method. The proposed method is a potential and better option for studying three dimensional particles by using digital holography.

  1. Constraining the magma flow record based on magmatic and magnetic data in La Gloria Pluton, central Chile

    NASA Astrophysics Data System (ADS)

    Gutierrez, F. J.; Payacán, I.; Gelman, S. E.; Bachmann, O.; Creative Physical Petrology Team

    2013-05-01

    The magmatic origin of the anisotropy of magnetic susceptibility (AMS) is examined in comparison with magmatic anisotropy data in a small, shallow, silicic magma reservoir in the upper crust. La Gloria Pluton (LGP) is a 10 Ma granodiorite/quartz monzonite of about 250 km3 located in the southern Andes, central Chile. LGP represents a particularly simple case of a silicic intrusion that was assembled in only a few pulses and cooled over a short time interval. Hornblende, biotite and minor magnetite are ubiquitous mafic phases. The AMS tensor indicates that magnetic fabric has an oblate shape (i.e. magnetic foliation is higher than magnetic lineation). Lineations are weak (values up to 1.05), have a N-NW trend with a nearly horizontal dip and are interpreted to represent axisymmetric convection parallel to the main pluton elongation. Foliations are more pronounced (values up to 1.14), having NW trends and dips that vary gradually from vertical at the walls, to horizontal at the center and near the roof of the chamber. We selected 12 samples from AMS sites to obtain petrographic data (well-distributed throughout the pluton, containing samples from the walls, the center and the roof of LGP), and then, determine the magmatic fabric (anisotropy, lineation, foliation). We made 3 oriented thin sections per sample oriented with the AMS. Magmatic anisotropy data were obtained by measuring mineral length, width and orientation in photomicrographs of the three main planes of the AMS tensor, producing 3-D mineral data which were collected for plagioclase and amphibole + bitotite independently. For each site, a Bingham distribution with 95% of confidence is used to determine the mean mineral orientations and their angle difference with the AMS axes. Magmatic anisotropy tensor and rotations with respect to the AMS tensor are determined using both eigenvalues and minimization algorithms. Preliminary results indicate that crystals are coherently oriented in both mineral groups, and that magmatic anisotropy values are similar for all crystals and consistent with AMS data. Based on fluid dynamical numerical simulations of LGP, we interpret both magmatic and magnetic anisotropy as a consequence of shear during late magmatic convection, near the magma locking point along solidification fronts. Acknowledgments This research has been developed by the FONDECYT N°11100241 and PBCT-PDA07 projects granted by CONICYT (Chilean National Commission for Science and Technology). Gutierrez and Bachmann were supported by U.S. National Science Foundation (NSF) grant EAR-080982 during the completion of this research. Gelman was supported by U.S. National Science Foundation (NSF) grant DGE-0718124.

  2. PROGNOSTIC FACTORS FOR PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMAS TREATED WITH HIGH-DOSE METHOTREXATE-BASED CHEMO-RADIOTHERAPY

    PubMed Central

    Nagane, Motoo; Lee, Jeunghun; Shishido-Hara, Yukiko; Suzuki, Kaori; Shimizu, Saki; Umino, Michiru; Kobayashi, Keiichi; Shiokawa, Yoshiaki

    2014-01-01

    BACKGROUND: Chemotherapy with high-dose methotrexate (HD-MTX) followed by whole brain radiotherapy (WBRT) is a conventional approach to treat primary central nervous system lymphomas (PCNSL), but some tumors relapse early leading to unfavorable outcome. Several biomarkers have been identified as prognostic factors in PCNSL, however, the correlation of both clinical factors including those related to MTX metabolism and B-cell differentiation and oncogenic biomarkers with response to and outcome by therapy is yet unclear. METHODS: We investigated 32 immunocompetent patients (19 males, 13 females) with PCNSL (all diffuse large B-cell type) treated with HD-MTX based therapy with or without WBRT since 2000 in our institution. Paraffin-embedded formalin-fixed tumor tissue sections were stained immunohistochemically with antibodies against following factors: B-cell differentiation markers (CD10, Bcl-6, Mum-1, CD138); MTX metabolism-related (MRP family, LRP, DHFR); cell cycle-related (p27KIP1, MIB-1); drug resistance-related (MGMT, MLH1, MSH2, MSH6, PMS2); and oncogenes (Myc, Bcl-2). Correlation between positivity of these factors and clinical outcomes were evaluated using logrank test and cox regression analysis. RESULTS: Among these factors, complete response to HD-MTX was significantly associated with longer progression-free survival (PFS)(P = 0.0012), while Bcl-6 expression as well as histological subtype (non-germinal center B-cell, non-GCB) was closely correlated with shorter PFS. Age (>60) (P = 0.006) and MSH2 expression (P = 0.017) were found to be better predictor for overall survival (OS), but in multivariate analysis, they were no longer significant. Other factors involved in MTX metabolism, DNA repair enzymes, and oncogenes did not affect outcome. CONCLUSIONS: Non-GCB subtype and Bcl-6 expression may be associated with worse outcome in patients with PCNSL treated with HD-MTX, while MTX-metabolism related factors did not influence prognosis. Further investigation is needed to assess Bcl-6 as a potential prognostic factor in PCNSL. SECONDARY CATEGORY: Clinical Neuro-Oncology.

  3. Pedostratigraphy of pre-Quaternary/Quaternary red paleosols from Central Europe based on geochemical and clay mineralogical proxies

    NASA Astrophysics Data System (ADS)

    Kovács, János; Újvári, Gábor; Seelos, Klemens; Varga, György; Ottner, Franz; Lukoczki, Georgina

    2013-04-01

    Geochemical and mineralogical studies of paleosols provide essential information for paleoclimatic and paleoenvironmental interpretation of continental deposits and can present a high-resolution proxy for paleoclimate. Consequently, paleosols can help to interpret the history of sediment deposition and the autogenic and allogenic processes that influenced a sedimentary basin. Paleosols are also helpful in stratigraphic studies, including sequence stratigraphic analyses. They are used for stratigraphic correlations at the local and basinal scale, and some workers have calculated sediment accumulation rates based on the degree of paleosol development. The horizons of paleosols are widely used as key horizons for the stratigraphic subdivision of continental sedimentary series. The reliability of usage of paleopedologic data has increased, especially with the development of methods of absolute and relative dating: radiocarbon, luminescent, paleomagnetic, amino acid, and paleontological (palynological and paleofaunistic) with geochemical and clay mineralogical data. The use of paleosols as components of the stratigraphic record has increased, especially after paleosols morphotypical features of different ages were studied. Paleosols in various sediment sections were once compound units of soil covers of different ages. Results from geochemical climofunctions applied to Upper Pliocene-Lower Pleistocene red clays and paleosols located in East-Central Europe (Austria, Slovakia, Hungary, Serbia and Romania) together with other geochemical data, clay mineralogy and fossil record, indicate that there were three major periods of their development. 1. The older type red clay/paleosol (age ~4.2-3.2 Ma) is red kaolinitic clay containing typically disordered kaolinite, mixed-layer smectite/kaolinite, smectite and little gibbsite. It was formed in the local subaerial weathering crust in warm, humid, subtropical or monsoon climate. 2. The younger type (age ~3.2-2.5 Ma) contains red (or "reddish") clay beds. It contains relatively fresh material (illite, chlorite), the weathering products are predominantly smectite and goethite formed under warm and drier climate in environmental conditions of savannah and steppe or forest steppe. 3. The basal red paleosol layer of the loess-paleosol series (age ~1.0-0.5 Ma) contain similar material as the 2nd type. The slightly but significantly lesser degree of weathering (more illite and chlorite, less smectite) indicates cooling of the climate. This contribution was made possible through financial support by 'Developing Competitiveness of Universities in the South Transdanubian Region (SROP-4.2.1.B-10/2/KONV-2010-0002)' and Austrian Agency for International Education & Research, financed by the Scholarship Foundation of the Republic of Austria (OeAD). It was additionally supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences for G. Újvári.

  4. Adapting to Climate Variability and Change: Experiences from Cereal-Based Farming in the Central Rift and Kobo Valleys, Ethiopia

    NASA Astrophysics Data System (ADS)

    Kassie, Belay Tseganeh; Hengsdijk, Huib; Rötter, Reimund; Kahiluoto, Helena; Asseng, Senthold; Van Ittersum, Martin

    2013-11-01

    Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions—the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20-30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977-2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers’ perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new risks outside the range of current experiences. To enable farmers to adapt to these impacts critical technological, institutional, and market-access constraints need to be removed. Inconsistencies between farmers’ perceptions and observed climate trends (e.g., decrease in annual rainfall) could lead to sub-optimal or counterproductive adaptations, and therefore must be removed by better communication and capacity building, for example through Climate Field Schools. Enabling strategies, which are among others targeted at agricultural inputs, credit supply, market access, and strengthening of local knowledge and information services need to become integral part of government policies to assist farmers to adapt to the impacts of current and future climate change.

  5. Distinct Characteristics of Small Cell Lung Cancer Correlate With Central or Peripheral Origin: Subtyping Based on Location and Expression of Transcription Factor TTF-1.

    PubMed

    Miyauchi, Eisaku; Motoi, Noriko; Ono, Hiroshi; Ninomiya, Hironori; Ohyanagi, Fumiyoshi; Nishio, Makoto; Okumura, Sakae; Ichinose, Masakazu; Ishikawa, Yuichi

    2015-12-01

    Small-cell lung carcinoma (SCLC) is a type of lung cancer with neuroendocrine differentiation and a poor prognosis that is widely believed to arise in the central lung. Thyroid transcription factor-1 (TTF-1) is a peripheral marker of lung adenocarcinoma that is also highly expressed in SCLC. In this study, we examined whether SCLC is really a central-type tumor and the relationship between tumor location, TTF-1 expression and prognosis of SCLC.Ninety six SCLCs, diagnosed from biopsies or surgical materials, for which detailed computed tomography (CT) images were available, were collected consecutively from Japanese patients between 2004 and 2011. We examined the location of the primary tumor (central or peripheral) using thin-sliced CT, a TTF-1 immunohistochemical expression, and clinicopathology including prognosis.Of the 96 SCLCs, 74% (71/96) were of the peripheral type and found to have a significantly worse prognosis than central-type tumors. TTF-1 immunoreactivity was identified in 79 tumors (82%), 78% of which (62/79) were of the peripheral type and 22% of which were central. TTF-1 expression was significantly correlated with peripheral location (P = 0.030). Multivariate analysis revealed that high TNM stages and the peripheral location were independent markers for poor survival.The majority of SCLCs were of the peripheral type. The peripheral-type SCLC expressed TTF-1 more frequently and had a poorer prognosis than central-type tumors did. Further analysis on original sites of SCLC, using molecular methodology, or based on another ethnicity, should be warranted. PMID:26705222

  6. Noninvasive Central Systolic Blood Pressure Is More Strongly Related to Kidney Function Decline Than Peripheral Systolic Blood Pressure in a Chinese Community-Based Population.

    PubMed

    Fan, Fangfang; Qi, Litong; Jia, Jia; Xu, Xin; Liu, Yan; Yang, Yang; Qin, Xianhui; Li, Jianping; Li, Haixia; Zhang, Yan; Huo, Yong

    2016-06-01

    This study aimed to investigate the association of noninvasive central aortic blood pressure with kidney function decline in a Chinese community-based population with normal kidney function at baseline. A total of 3153 Chinese participants from an atherosclerosis cohort were included in our analysis. The primary outcome was renal function decline defined as a drop in estimated glomerular filtration rate (eGFR) category accompanied by a ≥25% drop in eGFR from baseline; or a sustained decline in eGFR of >5 mL/min per 1.73 m(2)/y. The secondary outcomes were rapid eGFR decline (a decline in eGFR of >3 mL/min per 1.73 m(2)/y) and new incidence of chronic kidney disease. Participants were 56.6±8.5 years old, 36.0% were males, and 48.8% had hypertension. Mean (SD) baseline eGFR was 101.2±10.6 mL/min per 1.73 m(2) After a mean 2.35-year follow-up, the incidence of renal function decline, rapid eGFR decline and chronic kidney disease were 7.3%, 19.7%, and 0.7%, respectively. In multivariate logistic-regression analyses, central and peripheral systolic blood pressure (SBP) were both independently associated with all outcomes after adjustment for various confounders. When peripheral SBP was forced into the model with central SBP simultaneously, its significant association with the 3 outcomes all disappeared; however, central SBP was still significantly related with all outcomes even after further adjusting peripheral SBP. In conclusion, central SBP is a stronger predictor compared with peripheral SBP for early kidney function decline in a Chinese community-based population with normal kidney function at baseline. PMID:27141056

  7. The case of diagnostics of invasive pulmonary aspergillosis by in vivo probe-based confocal laser endomicroscopy of central and distal airways

    PubMed Central

    Danilevskaya, Olesya; Averyanov, Alexander; Klimko, Nikolay; Lesnyak, Viktor; Sorokina, Anastasia; Sazonov, Dmitry; Zabozlaev, Fedor

    2014-01-01

    We present a case of 41-year-old patient with invasive pulmonary aspergillosis (IPA) in which probe-based confocal laser endomicroscopy (pCLE) imaging of central and distal airways was first performed in vivo. pCLE imaging showed the signs of complete or partial destruction of elastin network of alveolar wall with fibrillar branching fluorescent structures in the zone with typical IPA changes on HRCT. PMID:25180153

  8. [Metastatic tumor implantation from a primary cancer of the base of the tongue at the site of placement of a central venous portacath].

    PubMed

    Tixier, H; Fraisse, J; Bruchon, Y; Cuisenier, J

    2009-10-01

    Central venous catheter placement with an implanted port (portacath) is used to provide long-term venous access. We report a case of metastatic implantation at a port site from a primary cancer of the base of the tongue. Insertion of portacaths must be performed using full sterile precautions to avoid spread of tumor cells; in no case should the port site incisions be in contact with the surgical field in which the tumor resection was performed. PMID:19833338

  9. Analysis of bacterial core communities in the central Baltic by comparative RNA–DNA-based fingerprinting provides links to structure–function relationships

    PubMed Central

    Brettar, Ingrid; Christen, Richard; Höfle, Manfred G

    2012-01-01

    Understanding structure–function links of microbial communities is a central theme of microbial ecology since its beginning. To this end, we studied the spatial variability of the bacterioplankton community structure and composition across the central Baltic Sea at four stations, which were up to 450 km apart and at a depth profile representative for the central part (Gotland Deep, 235 m). Bacterial community structure was followed by 16S ribosomal RNA (rRNA)- and 16S rRNA gene-based fingerprints using single-strand conformation polymorphism (SSCP) electrophoresis. Species composition was determined by sequence analysis of SSCP bands. High similarities of the bacterioplankton communities across several hundred kilometers were observed in the surface water using RNA- and DNA-based fingerprints. In these surface communities, the RNA- and DNA-based fingerprints resulted in very different pattern, presumably indicating large difference between the active members of the community as represented by RNA-based fingerprints and the present members represented by the DNA-based fingerprints. This large discrepancy changed gradually over depth, resulting in highly similar RNA- and DNA-based fingerprints in the anoxic part of the water column below 130 m depth. A conceivable mechanism explaining this high similarity could be the reduced oxidative stress in the anoxic zone. The stable communities on the surface and in the anoxic zone indicate the strong influence of the hydrography on the bacterioplankton community structure. Comparative analysis of RNA- and DNA-based community structure provided criteria for the identification of the core community, its key members and their links to biogeochemical functions. PMID:21697960

  10. A new kind of node centrality in directed weighted networks based on the demands of network clients

    NASA Astrophysics Data System (ADS)

    Ma, Lili; Jiang, Xin; Zhang, Zhanli; Tang, Shaoting; Zheng, Zhiming

    2011-08-01

    To reveal the correlation between the demands of network clients and the safety and robustness of real-world networks, we propose client demand centrality (CDC) in order to quantify the contributions of nodes in the transportation processes in directed weighted networks. CDC is defined by incorporating not only the topology and dynamics of the network but also the demands of network clients. The centrality measures node potential to ensure acceptable and successful transportation for clients and does quite well in distinguishing the roles of different nodes in the network. Simulation results show that node CDC has Gaussian distributions in directed networks with different link weight distributions, and the expected value of the Gaussian distribution increases from negative to positive with a decrease of the client demand. In particular, for directed scale-free networks with the scale-free link weight distribution, the network CDC is only correlated with the degree structure of the network when the client demand is large.

  11. TrajGraph: A Graph-Based Visual Analytics Approach to Studying Urban Network Centralities Using Taxi Trajectory Data.

    PubMed

    Huang, Xiaoke; Zhao, Ye; Yang, Jing; Zhang, Chong; Ma, Chao; Ye, Xinyue

    2016-01-01

    We propose TrajGraph, a new visual analytics method, for studying urban mobility patterns by integrating graph modeling and visual analysis with taxi trajectory data. A special graph is created to store and manifest real traffic information recorded by taxi trajectories over city streets. It conveys urban transportation dynamics which can be discovered by applying graph analysis algorithms. To support interactive, multiscale visual analytics, a graph partitioning algorithm is applied to create region-level graphs which have smaller size than the original street-level graph. Graph centralities, including Pagerank and betweenness, are computed to characterize the time-varying importance of different urban regions. The centralities are visualized by three coordinated views including a node-link graph view, a map view and a temporal information view. Users can interactively examine the importance of streets to discover and assess city traffic patterns. We have implemented a fully working prototype of this approach and evaluated it using massive taxi trajectories of Shenzhen, China. TrajGraph's capability in revealing the importance of city streets was evaluated by comparing the calculated centralities with the subjective evaluations from a group of drivers in Shenzhen. Feedback from a domain expert was collected. The effectiveness of the visual interface was evaluated through a formal user study. We also present several examples and a case study to demonstrate the usefulness of TrajGraph in urban transportation analysis. PMID:26529696

  12. ecological geological maps: GIS-based evaluation of the Geo-Ecological Quality Index (GEQUI) in Sicily (Central Mediterranean)

    NASA Astrophysics Data System (ADS)

    Nigro, Fabrizio; Arisco, Giuseppe; Perricone, Marcella; Renda, Pietro; Favara, Rocco

    2010-05-01

    The condition of landscapes and the ecological communities within them is strongly related to levels of human activity. As a consequence, determining status and trends in the pattern of human-dominated landscapes can be useful for understanding the overall conditions of geo-ecological resources. Ecological geological maps are recent tools providing useful informations about a-biotic and biotic features worldwide. These maps represents a new generation of geological maps and depict the lithospheric components conditions on surface, where ecological dynamics (functions and properties) and human activities develop. Thus, these maps are too a fundamental political tool to plan the human activities management in relationship to the territorial/environmental patterns of a date region. Different types of ecological geological maps can be develop regarding the: conditions (situations), zoning, prognosis and recommendations. The ecological geological conditions maps reflects the complex of parameters or individual characteristics of lithosphere, which characterized the opportunity of the influence of lithosphere components on the biota (man, fauna, flora, and ecosystem). The ecological geological zoning maps are foundamental basis for prognosis estimation and nature defenses measures. Estimation from the position of comfort and safety of human life and function of ecosystem is given on these maps. The ecological geological prognosis maps reflect the spatial-temporary prognoses of ecological geological conditions changing during the natural dynamic of natural surrounding and the main-during the economic mastering of territory and natural technical systems. Finally, the ecological geological recommendation maps are based on the ecological geological and social-economical informations, aiming the regulation of territory by the regulation of economic activities and the defense of bio- and socio-sphere extents. Each of these maps may also be computed or in analytic or in synthetic way. The first, characterized or estimated, prognosticated one or several indexes of geological ecological conditions. In the second type of maps, the whole complex is reflected, which defined the modern or prognosticable ecological geological situation. Regarding the ecological geological zoning maps, the contemporary state of ecological geological conditions may be evaluated by a range of parameters into classes of conditions and, on the basis of these informations, the estimation from the position of comfort and safety of human life and function of ecosystem is given. Otherwise, the concept of geoecological land evaluation has become established in the study of landscape/environmental plannings in recent years. It requires different thematic data-sets, deriving from the natural-, social- and amenity-environmental resources analysis, that may be translate in environmental (vulnerability/quality) indexes. There have been some attempts to develop integrated indices related to various aspects of the environment within the framework of sustainable development (e.g.: United Nations Commission on Sustainable Development, World Economic Forum, Advisory Board on Indicators of Sustainable Development of the International Institute for Sustainable Development, Living Planet Index established by the World Wide Fund for Nature, etc.). So, the ecological geological maps represent the basic tool for the geoecological land evaluation policies and may be computed in terms of index-maps. On these basis, a GIS application for assessing the ecological geological zoning is presented for Sicily (Central Mediterranean). The Geo-Ecological Quality Index (GEQUI) map was computed by considering a lot of variables. Ten variables (lithology, climate, landslide distribution, erosion rate, soil type, land cover, habitat, groundwater pollution, roads density and buildings density) generated from available data, were used in the model, in which weighting values to each informative layer were assigned. An overlay analysis was carried out, allowing to classify the region into five classes: bad, poor, moderate, good and high.

  13. Estimation of Recurrence Interval of Large Earthquakes on the Central Longmen Shan Fault Zone Based on Seismic Moment Accumulation/Release Model

    PubMed Central

    Zhang, Shimin

    2013-01-01

    Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 1017 N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region. PMID:23878524

  14. Estimation of recurrence interval of large earthquakes on the central Longmen Shan fault zone based on seismic moment accumulation/release model.

    PubMed

    Ren, Junjie; Zhang, Shimin

    2013-01-01

    Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 10¹⁷ N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region. PMID:23878524

  15. ASNT central certification program

    NASA Astrophysics Data System (ADS)

    Spring, Robert W.; Snell, John R., Jr.

    1997-04-01

    The American Society of Nondestructive Testing (ASNT) has recently established a new central certification program. This program will allow individuals who meet the requirements to receive a 'portable' certificate. Augmenting the existing employer-based certification, this program will have significant impact on industries that may ultimately require nondestructive testing (NDT) personnel to have central certification. This paper explains show ASNT has structured central certification and when and how it will effect thermal/infrared thermography (T/IRT) personnel. The paper also discusses the industry specific certification process.

  16. Primary failure of eruption combined with bilateral transmigration of mandibular canines, transposition, torus palatinus, and class III incisor relationship: A rare case report

    PubMed Central

    Elhag, Salma Babiker Idris; Abdulghani, Ashraf Sidig Idris

    2015-01-01

    Eruption disorders are numerous varying from delayed to complete failure of eruption. Primary failure of eruption (PFE) is a rare condition that involves arrested eruption of teeth with the absence of local or general contributory factors. Another rare and clinically challenging phenomenon is canine transmigration which is the intra-osseous movement of impacted canines across the midline. This report presents the first case of combined failure of eruption of multiple teeth with bilateral mandibular canine transmigration, transposition of upper canine and the first premolar, torus palatinus, and class III incisor relationship in a 33-year-old asymptomatic and nonsyndromic female patient. PMID:26929701

  17. Primary failure of eruption combined with bilater