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Sample records for aplasia irreversible por

  1. Aplasia of the optic nerve.

    Science.gov (United States)

    Tang, Daniel C W; Man, Eric M W; Cheng, Sunny C S

    2015-08-01

    Aplasia of the optic nerve is an extraordinarily rare congenital anomaly that affects one or both optic nerves and is associated with the absence of the central retinal vessel and retinal ganglion cells. We report a case of unilateral optic nerve aplasia in a 4-month-old infant who was found to have left microphthalmos on routine postnatal checkup. Family history, antenatal history, and systemic evaluation were unremarkable. Magnetic resonance imaging showed absent left optic nerve with left microphthalmos. The optic chiasm was present and slightly deviated towards the right side. The remaining cerebral and ocular structures were normal.

  2. A Rare Case of Aplasia Cutis Congenita

    Directory of Open Access Journals (Sweden)

    Sumita Mehta

    2017-10-01

    Full Text Available Aplasia cutis congenita is a heterogenous group of disorders characterized by the absence of a portion of skin either localized or widespread at birth. Most commonly seen on the scalp (84%, it can affect any part of the body, including the trunk and limbs. We report a case of a baby born with aplasia cutis congenital managed conservatively.

  3. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible Pure red cell aplasia after ABO incompatible bone marrow transplantation

    OpenAIRE

    E. Bulliorsky; C. Shanley; G. Stemmelin; J. Ceresetto; O. Rabinovich

    2002-01-01

    El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH) con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoy...

  4. Diphenylhydantoin-induced pure red cell aplasia.

    Science.gov (United States)

    Rusia, Usha; Malhotra, Purnima; Joshi, Panul

    2006-01-01

    Pure red cell aplasia is an uncommon complication of diphenylhydantoin therapy. It has not been reported in Indian literature. Awareness of the entity helps in establishing the cause of anaemia in these patients and alerts the physicians to the need of comprehensive haematological monitoring in these patients. A case of 58-year-old male who developed pure red cell aplasia following three months of diphenylhydantoin therapy is reported here.

  5. [Morphogenesis of vaginal aplasia. Therapeutic deductions].

    Science.gov (United States)

    Minh, H N; Smadja, A; Belaisch, J

    1985-01-01

    On the basis of the studies of the embryogenesis of the vagina, the authors consider that malformations classically described as being partial aplasia should not be separated from the total absence of the vagina. The important feature is the association of a functioning or non functioning uterus with the absence of the vagina. They believe that it is incorrect to describe the pouch of menstrual retention associated with a functioning uterus as "haematocolpos" and that is not justified to describe the cup-shaped vestibular depression as "hemi-vagina". According to the authors, although vaginal aplasia with a functioning uterus forming a pouch of menstrual retention constitutes an absolute indication for surgery, surgery is not justified in cases of vaginal aplasia with a non functioning uterus. If Frank's method fails in these cases, the patient or the couple should be referred to a sexologist, as women with this anomaly retain a perfect femininity, although unable to conceive.

  6. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible Pure red cell aplasia after ABO incompatible bone marrow transplantation

    Directory of Open Access Journals (Sweden)

    E. Bulliorsky

    2002-12-01

    Full Text Available El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoyetina o plasmaféresis, con relativo éxito. Algunos autores han informado también la utilización de globulina antilinfocitaria, asumiendo que dicha aplasia selectiva de la serie roja en la médula ósea trasplantada es mediada por un mecanismo inmune. En este trabajo se describe un paciente portador de una leucemia aguda en quien se realizó un TCPH alogeneico (ABO incompatible con su donante. Teniendo niveles bajos de aglutininas contra el grupo sanguíneo de la donante, desarrolló una aplasia pura de serie roja post - TCPH. La misma no mejoró con tratamiento con eritropoyetina o con un refuerzo de progenitores hematopoyéticos de sangre periférica de la misma donante (boost, resolviéndose totalmente luego de un tratamiento exitoso con globulina antilinfocitaria de origen equino.ABO incompatibility in allogeneic bone marrow transplantation may be associated with incomplete or delayed erythroid engraftment, being pure red cell aplasia (PRCA the most severe complication in this setting. Attempts for the treatment of PRCA have been made with erythropoietin or with plasmapheresis with relative success, and some authors have reported the reversibility of PRCA with antilymphocyte globulin (ALG or ATG, based on the assumption that PRCA might be immunologically mediated. We report herewith a patient with acute leukemia who developed post - BMT pure red cell aplasia. His sibling donor (sister was HLA identical and ABO incompatible, having low agglutinin

  7. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible

    OpenAIRE

    E. Bulliorsky; C. Shanley; G. Stemmelin; J. Ceresetto; O. Rabinovich

    2002-01-01

    El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH) con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoy...

  8. Acquired pure red cell aplasia in children

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    Sujata R Dafale

    2012-01-01

    Full Text Available Acquired Pure Red Cell Aplasia (PRCA is a rare occurrence in children.This is a case of an eight year old girl child who developed acquired PRCA secondary to long term intake of sodium Valproate. This case is reported to review the causes of PRCA in children and to reconsider the use of drugs of longer duration in children and adults.

  9. Aplasia of the parotid gland in Down syndrome.

    Science.gov (United States)

    Ferguson, M M; Ponnambalam, Y

    2005-04-01

    Salivary gland aplasia has not to our knowledge been previously reported in association with Down syndrome. We present a case of bilateral parotid aplasia in a patient with Down syndrome. Clinically he had aplasia of the major salivary glands and symptoms of xerostomia. Thirteen other family members over three generations were examined, and all had functional parotid glands. We reviewed publications about Down syndrome and salivary aplasia, together with the data regarding his other clinical problems and family background. His oral problems were inadequate plaque control, dental caries, and erosion of the teeth.

  10. Reconstruction of bilateral tibial aplasia and split hand-foot ...

    African Journals Online (AJOL)

    Background: Tibial aplasia is of heterogeneous aetiology, the majority of reports are sporadic. We describe the reconstruction procedures in two subjects - a daughter and father manifested autosomal dominant (AD) inheritance of the bilateral tibial aplasia and split hand-foot syndrome. Materials and Methods: ...

  11. Aplasia Cutis Congenita Association with Fetus Papyraceus

    OpenAIRE

    Ahmet Özdemir; Osman Baştuğ; Serra Alçı

    2015-01-01

    Aplasia cutis congenita (ACC) is a rare malformation characterized by localized or a wide area absence of tissue. The disease may involve any site of the body, although usually seen on the scalp. Observed one in 10.000 births, it can occur as the ACC as an isolated lesion and may be associated with cleft palate/lip, syndactyly, absence of fingers, eye abnormalities and congenital heart disease. ACC’s a rare form due to intrauterine twin, which is a form of ex. Large lesions tha...

  12. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible

    Directory of Open Access Journals (Sweden)

    E. Bulliorsky

    2002-12-01

    Full Text Available El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoyetina o plasmaféresis, con relativo éxito. Algunos autores han informado también la utilización de globulina antilinfocitaria, asumiendo que dicha aplasia selectiva de la serie roja en la médula ósea trasplantada es mediada por un mecanismo inmune. En este trabajo se describe un paciente portador de una leucemia aguda en quien se realizó un TCPH alogeneico (ABO incompatible con su donante. Teniendo niveles bajos de aglutininas contra el grupo sanguíneo de la donante, desarrolló una aplasia pura de serie roja post - TCPH. La misma no mejoró con tratamiento con eritropoyetina o con un refuerzo de progenitores hematopoyéticos de sangre periférica de la misma donante (boost, resolviéndose totalmente luego de un tratamiento exitoso con globulina antilinfocitaria de origen equino.

  13. [Aplasia cutis congenita: Update and management].

    Science.gov (United States)

    Belkhou, A; François, C; Bennis, Y; Duquennoy-Martinot, V; Guerreschi, P

    2016-10-01

    Congenital skin aplasia, or aplasia cutis congenita (ACC) is a rare congenital disease. It is characterized by the absence of skin at birth, localized or widespread, of one or several areas. This condition commonly involve the scalp but can also involve more rarely the trunk or limbs. However it is most frequently an isolated disorder, it can be associated with other anomalies, such as the Adams-Oliver syndrome, the association with a fetus papyraceus or with an epidermolysis bullosa. Many hypothesis have been suggested: vascular, genetic, traumatic, pharmacological or an anomaly in the neural tube closure process, but the exact mechanism is still unknown. Morbidity and mortality of this malformation depends on the affected area and the size of the defect. The main risk is the infection, hemorrhage and thrombosis in the case of a scalp defect with an underlying bone defect, the exposure of the meninges and the superior sagittal sinus. The initial management of ACC will therefore involve several plastic surgery techniques, from more simple to more complex, using conservative wound care to flaps techniques. Other techniques can be performed later, in the management of ACC sequelae, such as skin expansion for scarring alopecia. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Pulmonary Aplasia in an Adult : A Case Report

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    Nurettin Yiyit

    2016-01-01

    Full Text Available Pulmonary aplasia is a rare congenital anomaly in which there are absence of pulmonary vessels, bronchus and parenchyma. It is distinguished from pulmonary agenesis by the presence of rudimentary stump bronchus. Patients are usually diagnosed in childhood. Patients without additional anomaly and the patients with mild disease can be diagnosed in adulthood. The left lung was not observed at the chest X-ray of 19-year-old male patient with respiratory distress in exercise. Left lung aplasia was diagnosed by computed tomography and ventilation perfusion scintigraphy. The patients with lung aplasia have an increased risk of infections. Therefore the follow-up of the patients is important.

  15. Aplasia cutis congenita with two completely different presentations

    Directory of Open Access Journals (Sweden)

    Sanchaita Bala

    2014-01-01

    Full Text Available Aplasia cutis congenita is a rare disorder, which presents with congenital absence of skin. Besides isolated presentation, it may manifest with other developmental malformation of cardiovascular, gastrointestinal, genitourinary and central nervous systems, and malformation syndromes such as chromosomal abnormalities, Adams-Oliver syndrome, Bart′s syndrome, and Johanson-Bilzzard syndrome. Here, we present two cases of aplasia cutis congenita, which represent two different types of the disease. The first case presented as non-syndromic aplasia cutis congenita of scalp, and the other case presented as a part of Bart′s syndrome.

  16. Unilateral aplasia of both cruciate ligaments

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    Liem Dennis

    2010-02-01

    Full Text Available Abstract Aplasia of both cruciate ligaments is a rare congenital disorder. A 28-year-old male presented with pain and the feeling of instability of his right knee after trauma. The provided MRI and previous arthroscopy reports did not indicate any abnormalities except cruciate ligament tears. He was referred to us for reconstruction of both cruciate ligaments. The patient again underwent arthroscopy which revealed a hypoplasia of the medial trochlea and an extremely narrow intercondylar notch. The tibia revealed a missing anterior cruciate ligament (ACL footprint and a single bump with a complete coverage with articular cartilage. There was no room for an ACL graft. A posterior cruciate ligament could not be identified. The procedure was ended since a ligament reconstruction did not appear reasonable. A significant notch plasty if not a partial resection of the condyles would have been necessary to implant a ligament graft. It is most likely that this would not lead to good knee stability. If the surgeon would have retrieved the contralateral hamstrings at the beginning of the planned ligament reconstruction a significant damage would have occurred to the patient. Even in seemingly clear diagnostic findings the arthroscopic surgeon should take this rare abdnormality into consideration and be familiar with the respective radiological findings. We refer the abnormal finding of only one tibial spine to as the "dromedar-sign" as opposed to the two (medial and a lateral tibial spines in a normal knee. This may be used as a hint for aplasia of the cruciate ligaments.

  17. Aplasia cutis congenita with two completely different presentations

    OpenAIRE

    Sanchaita Bala; Sumit Sen; Atul Jain; Amlan K Biswas

    2014-01-01

    Aplasia cutis congenita is a rare disorder, which presents with congenital absence of skin. Besides isolated presentation, it may manifest with other developmental malformation of cardiovascular, gastrointestinal, genitourinary and central nervous systems, and malformation syndromes such as chromosomal abnormalities, Adams-Oliver syndrome, Bart′s syndrome, and Johanson-Bilzzard syndrome. Here, we present two cases of aplasia cutis congenita, which represent two different types of the disease....

  18. Unilateral submandibular gland aplasia masquerading as cancer nodal metastasis.

    Science.gov (United States)

    Shipchandler, Taha Z; Lorenz, Robert R

    2008-01-01

    Five reports have examined unilateral submandibular gland aplasia. The purposes of this report are to demonstrate submandibular gland aplasia leading to contralateral gland hypertrophy in the setting of oral cavity cancer and to discuss the corresponding diagnostic and management challenges. This study is a case report of a 60-year-old male who presented with pain on the right side of the mobile tongue. This report uses literature review. A 60-year-old male presented with pain on the right side of the mobile tongue. Subsequent results of punch biopsy revealed squamous cell carcinoma in situ with foci of microinvasion of the tongue. Head and neck examination revealed no abnormalities. The patient underwent a wide-local excision of the tongue lesion. Postoperative computed tomographic (CT) scan showed an asymmetric mass on the ipsilateral side of the cancer in the region of the submandibular gland. The gland was noted to be abnormally large. A diagnosis of contralateral submandibular gland aplasia was made. The patient is cancer-free at 2 years postlocal excision. Salivary gland aplasia is an extremely rare disorder and is often associated with various congenital syndromes. Unilateral submandibular gland aplasia is even rarer with ours representing the sixth reported case. Aplasia is believed to stem from a regional disturbance in early fetal development. Common symptoms can include dysphagia, dry mouth, decreased taste, and tooth decay. In the presence of a history of oral cavity cancer, unilateral submandibular gland aplasia poses a challenge during postoperative cancer follow-up. Unilateral submandibular gland aplasia in the setting of oral cavity cancer poses a unique challenge for cancer follow-up. Hypertrophy of the submandibular gland on the other side can masquerade as nodal metastasis. Head and neck examination as well as CT scan can be inconclusive. Regular confirmatory tests such as fine needle aspiration biopsy and positron emission tomography/CT for

  19. Congenital aplasia of the semicircular canals.

    Science.gov (United States)

    Satar, Bulent; Mukherji, Suresh K; Telian, Steven A

    2003-05-01

    To describe the underrecognized inner ear malformation characterized by complete aplasia of the labyrinthine semicircular canals associated with a relatively well-formed cochlea, to investigate its relationship with known syndromic forms of hearing loss, and to hypothesize regarding the potential embryopathogenesis of this anomaly. A retrospective case review consisting of cases of sensorineural hearing loss with radiographic evidence demonstrating agenesis of the semicircular canals associated with a cochlea that was either morphologically normal or sufficiently well developed to accommodate the full insertion of a cochlear implant electrode. Cases were identified by computerized tomography findings that identified the anomaly under study. Departments of otolaryngology and radiology in a tertiary referral center, with a large cochlear implant program serving over 800 patients, more than half of whom are children. Fifteen patients with the anomaly under study were identified. Each patient underwent a complete otologic examination, audiometric studies, and high resolution computerized tomography of the temporal bone in axial and coronal planes. The bony morphology of the cochlea, round and oval windows, vestibule, semicircular canals, and vestibular aqueduct, and the course of the facial nerve were examined. Auditory findings and otologic treatment are presented. Of the 15 identified patients, 4 were nonsyndromic, 9 had CHARGE association (Coloboma of the eye, congenital Heart defects, choanal Atresia, mental and/or growth Retardation, Genital hypoplasia, and Ear anomalies and/or deafness), 1 met criteria for Noonan's syndrome, and one had features of both these syndromes. Although the cochlea was present in all cases, the cochlear morphology was usually abnormal in the CHARGE association patients. Of the 20 ears in the CHARGE subjects, only 3 ears (15%) were seen to have completely normal development of the cochlea in both the basal and upper turns. The others

  20. [Surgical management of aplasia cutis congenita].

    Science.gov (United States)

    Betancourth-Alvarenga, J E; Vázquez-Rueda, F; Vargas-Cruz, V; Paredes-Esteban, R M; Ayala-Montoro, J

    2015-11-01

    Aplasia cutis congenita (ACC) is a rare congenital malformation that commonly involves the scalp, but can affect pericranium, bone and dura mater. Complications are rare, but can be fatal, so early treatment must be achieved. The treatment remains controversial with no consensus between the conservative and surgical approach. The aim of this study is to describe our experience in the management of ACC. Retrospective review of the medical records of all children up to 14 years diagnosed with ACC and treated between 2000 and 2013. There were a total of 22 cases of ACC with lesions ranging from 1cm (0.79 cm(2)) to 14cm (153.94 cm(2)). ACC of the scalp was found in 18 cases, with 3 in extremities and 1 in trunk. Conservative treatment was performed on 9 patients and 13 underwent surgical treatment (8 primary closures, 2 plasties, 2 skin grafts, and 1 skin flap). Two patients died due to complications of other diseases not related with the ACC. ACC is a rare disease that can be fatal. A complete initial assessment to establish early treatment is necessary to prevent this. Surgery should be considered as an initial therapeutic option in defects >4cm (>12.6 cm(2)) as it prevents the risk of fatal complications. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  1. Aplasia cutis congenita: report of 22 cases.

    Science.gov (United States)

    Mesrati, Hela; Amouri, Meriem; Chaaben, Hend; Masmoudi, Abdelrahmen; Boudaya, Sonia; Turki, Hamida

    2015-12-01

    Aplasia cutis congenita (ACC) is a rare malformation characterized by absent or scarred areas of skin at birth. Although most commonly found on the scalp, ACC can also involve other locations. Its etiology and pathogenesis remain unclear. To describe the epidemiologic, clinical, therapeutic, and evolutionary aspects of ACC through a hospital series. We conducted a retrospective study from 1995 to 2012 and reported all cases of ACC. We enrolled 22 cases (14 girls and eight boys) of ACC during 18 years. The mean age at diagnosis was 5.7 years. Sixteen ACC involved the scalp, five the trunk, and one the left buttock. ACC was oval-shaped in 20 cases, triangular in one case, and linear in one case. The mean size was 4 cm. ACC was associated with bone defects in two cases, various malformations in eight (37.1%), and with syndromic malformation in three (Adams-Olivier syndrome: two cases; Goltz syndrome: one case). Conservative treatment consisting of wound dressing with vaseline was indicated in six cases. Bone reconstruction was performed in two cases. Regular follow-up and no treatment was recommended in 14 cases. Our study emphasizes the frequent association of ACC with malformations (37.1%) and bone defects (9%). © 2015 The International Society of Dermatology.

  2. Right pulmonary aplasia, aberrant left pulmonary artery, and bronchopulmonary sequestration with an esophageal bronchus

    International Nuclear Information System (INIS)

    Lee, Peter; McCauley, Roy; Westra, Sjirk; Baba, Timothy

    2006-01-01

    Pulmonary aplasia and bronchopulmonary foregut malformations in which a patent communication between the foregut and the pulmonary system is present are rare congenital abnormalities. Pulmonary aplasia associated with a pulmonary sling is an even rarer abnormality. We report a unique case of right pulmonary aplasia, aberrant left pulmonary artery, and bronchopulmonary sequestration with an esophageal bronchus diagnosed by multidetector helical CT. (orig.)

  3. Unilateral Aplasia of Mandibular Condyle: A Rare Case Entity

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    Anil G Ghom

    2011-01-01

    Full Text Available Aplasia of the mandibular condyle is extremely rare when not seen in association with or as a part of any syndrome. The incidence is estimated to be 1 in 5.600 births. Growth disturbances in the development of the mandibular condyle may occur in utero late in the first trimester and may result in disorders, such as aplasia or hypoplasia of the mandibular condyle. We report a case of aplasia of left mandibular condyle along with hypoplasia of right condylar head in a 20-year-old female patent. The patient reported to the clinic with the complaint of proclined upper front teeth, wanting to improve her esthetics. Clinical, conventional radiography and computer tomographic studies revealed the complete absence of condyle on the left and hypoplasia of the head of mandibular condyle on the right side. The etiology was unknown and on the basis of history, clinical study and radiological examination it was suggested to be of developmental origin.

  4. Treatment dilemma: conservative versus surgery in cutis aplasia congenita.

    Science.gov (United States)

    Bang, R L; Ghoneim, I E; Gang, R K; Al Najjadah, I

    2003-04-01

    Cutis aplasia congenita (CAC), a congenital absence of skin and its appendages, may extend into underlying muscles and bones. The scalp is the commonest site and it may be associated with acrania. CAC presents either as a thin transparent membrane, a black eschar, an ulcer or a healed scar. The dilemma of either immediate surgical management or conservative treatment is much more pronounced in the presence of acrania. Two patients with scalp lesions measuring 12 x 8 cm and 14 x 12 cm respectively and one patient with 4 cm wide circumferential trunk cutis aplasia treated conservatively are presented. The conservative treatment is simple, easy to carry out, and effective even for large defects; therefore, it is recommended in cutis aplasia congenita till complete healing. Surgical interventions such as tissue expansion and resurfacing, contracture release, etc. are for the correction of subsequent deformity at a later date.

  5. Irreversible processes kinetic theory

    CERN Document Server

    Brush, Stephen G

    2013-01-01

    Kinetic Theory, Volume 2: Irreversible Processes deals with the kinetic theory of gases and the irreversible processes they undergo. It includes the two papers by James Clerk Maxwell and Ludwig Boltzmann in which the basic equations for transport processes in gases are formulated, together with the first derivation of Boltzmann's ""H-theorem"" and a discussion of this theorem, along with the problem of irreversibility.Comprised of 10 chapters, this volume begins with an introduction to the fundamental nature of heat and of gases, along with Boltzmann's work on the kinetic theory of gases and s

  6. Aplasia of the parotid glands with accessory parotid tissue

    Energy Technology Data Exchange (ETDEWEB)

    Higley, Meghan J.; Walkiewicz, Thomas W.; Miller, Jeffrey H.; Curran, John G.; Towbin, Richard B. [Phoenix Children' s Hospital, Department of Radiology, Phoenix, AZ (United States)

    2010-03-15

    Congenital absence of the parotid gland is a rare entity. Absence is most commonly unilateral, and is not associated with accessory glandular tissue. In the majority of reported cases, parotid gland aplasia is seen with craniofacial abnormalities or hypoplasia of other ectodermal structures, particularly the lacrimal glands. We present a 14-year-old male with bilateral parotid gland aplasia detected incidentally on MRI of the brain and then confirmed on neck CT. The studies also revealed accessory parotid tissue superficial to the left masseter muscle. There were no associated craniofacial abnormalities. The lacrimal glands and submandibular glands were normal. (orig.)

  7. Aplasia and hypoplasia of the maxillary sinus: A case series

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    Nasim Jafari-Pozve

    2014-01-01

    Full Text Available Maxillary sinus aplasia and hypoplasia are rare conditions that can cause symptoms such as headaches and voice alteration. The majority of patients are asymptomatic, but these conditions must be noticed for importance of differential diagnosis such as infection and neoplasms. Conventional radiographs could not differentiate between inflammatory mucosal thickening, neoplasm, and hypoplasia of the sinus. Computed tomography (CT and also cone beam computed tomography (CBCT are the proper modalities to detect these conditions. In the present study, CBCT findings of three cases with maxillary sinus hypoplasia and aplasia are reported.

  8. Tissue expansion for correction of baldness in aplasia cutis congenita

    NARCIS (Netherlands)

    Beekmans, S.J.A.; Don Griot, J.P.W.; Niessen, F.B.; Mulder, J.W.

    2009-01-01

    Aplasia cutis is a congenital absence of the skin, usually presenting on the scalp. In 20% of all cases, part of the skull is also absent. A residual area of baldness may still be present some years after surgical or conservative treatment. It is possible to excise the scarred hairless region and

  9. Pure red cell aplasia following irradiation of an asymptomatic thymoma

    International Nuclear Information System (INIS)

    Shibata, Kazuo; Masaoka, Akira; Mizuno, Takeo; Ichimura, Hideki

    1982-01-01

    An unusual case of pure red-cell aplasia (PRCA) developed sixteen days after irradiation of an asymptomatic thymoma. After removal of the encapsulated thymoma there was no improvement in the anemia, and no response to adrenocortical and anabolic steroid hormones or immunosuppressive agents. (author)

  10. Pyloric atresia epidermolysis bullosa aplasia cutis syndrome: a case ...

    African Journals Online (AJOL)

    Pyloric atresia epidermolysis bullosa aplasia cutis syndrome: a case report and literature review. ... At birth, there was denuded skin over the right leg from the knee joint up to the middle of the right foot. Abdominal radiograph ... Examination indicated no signs of child abuse; the parents refused an autopsy exam for the child.

  11. Unilateral proximal focal femoral deficiency, fibular aplasia, tibial ...

    African Journals Online (AJOL)

    Rabah M. Shawky

    2014-04-30

    Apr 30, 2014 ... Unilateral proximal focal femoral deficiency, fibular aplasia, tibial campomelia and oligosyndactyly in an Egyptian child – Probable. FFU syndrome. Rabah M. ... We report for the first time an Egyptian child with a rare unilateral .... 4th and 5th metatarsal bones are absent), absent middle phalanx of the 2nd ...

  12. A Case of Aplasia Cutis Congenita, Type VII

    Science.gov (United States)

    Lee, Joung Sun; Lee, Jee Bum; Kim, Seong Jin; Won, Young Ho

    2008-01-01

    Aplasia cutis congenita (ACC) is a rare congenital defect in which localized or widespread areas of the skin are absent at birth. In the majority of cases, it is limited to the scalp especially on the vertex although other areas of the body may also be involved. Other congenital malformations can be associated with ACC. We present herein the case of a new born male with unilateral absence of skin on the extensor surface of the right lower leg. There was no associated malformation or skin disease such as blistering or nail abnormailty. According to the classification outlined by Frieden, the condition was diagnosed as type VII aplasia cutis congenita. The treatment of this large ulcer was conservative, wet dressing and prophylactic topical antibiotics. On follow up after 2 years showed that the patient was nearly cured of the ulcer and had only minimal scar formation. PMID:27303163

  13. Laparoscopic morcellation of didelphic uterus with cervical and renal aplasia.

    Science.gov (United States)

    Altchek, Albert; Brodman, Michael; Schlosshauer, Peter; Deligdisch, Liane

    2009-01-01

    This is a case report (and review of the literature) of a 12-year and 10-month-old girl with a rare congenital anomaly of uterus didelphys, unilateral cervix aplasia, and ipsilateral renal aplasia. She had severe dysmenorrhea from the first menses. In an effort to preserve fertility, a cervical fistula was made that closed over. A laparoscopic hemi-hysterectomy was done successfully and rapidly with laparoscopic morcellation. Because no ureter was present, it was not necessary to trace it. For this congenital anomaly, laparoscopic morcellation of the obstructed hemiuterus is the preferred treatment either as a primary procedure or as a secondary procedure following failure of a surgical cervical fistula for the young patient.

  14. A case of extensive aplasia cutis congenita: a conservative approach.

    Science.gov (United States)

    Starcevic, Mirta; Sepec, Marija Pozgaj; Zah, Vanja

    2010-01-01

    Aplasia cutis congenita is a rare, sporadic congenital malformation characterized by skin defects, sometimes extending to the underlying bone. We report a case of a boy born with a large rhomboid scalp and skull defect measuring 8 × 12 cm with no other anomalies. Conservative treatment led to the complete epithelization of the skin defect with secondary closure of the cranial vault without need for surgical intervention. © 2010 Wiley Periodicals, Inc.

  15. Pure Red Cell Aplasia Associated with Good Syndrome

    Directory of Open Access Journals (Sweden)

    Masayuki Okui

    2017-04-01

    Full Text Available Pure red cell aplasia (PRCA and hypogammaglobulinemia are paraneoplastic syndromes that are rarer than myasthenia gravis in patients with thymoma. Good syndrome coexisting with PRCA is an extremely rare pathology. We report the case of a 50-year-old man with thymoma and PRCA associated with Good syndrome who achieved complete PRCA remission after thymectomy and postoperative immunosuppressive therapy, and provide a review of the pertinent literature.

  16. Pure Red Cell Aplasia Following Thymothymectomy: A Case Report

    OpenAIRE

    CK RAO, Anuradha; NAYAL, Bhavna; MANOHAR, Chethan

    2013-01-01

    Thymoma, a rare epithelial neoplasm, is the most common anterior-superior mediastinal tumour. Thymoma can occur sporadically or in association with other conditions, such as myasthenia gravis, pure red cell aplasia (PRCA), and hypogammaglobulinemia. Only 5% of thymoma cases develop PRCA; however, 10–50% of patients presenting with PRCA have an associated spindle cell type thymoma. Thymoma complicated by PRCA is associated with a poor outcome. We report the case of a 38-year-old female who pre...

  17. Stochastic dynamics and irreversibility

    CERN Document Server

    Tomé, Tânia

    2015-01-01

    This textbook presents an exposition of stochastic dynamics and irreversibility. It comprises the principles of probability theory and the stochastic dynamics in continuous spaces, described by Langevin and Fokker-Planck equations, and in discrete spaces, described by Markov chains and master equations. Special concern is given to the study of irreversibility, both in systems that evolve to equilibrium and in nonequilibrium stationary states. Attention is also given to the study of models displaying phase transitions and critical phenomema both in thermodynamic equilibrium and out of equilibrium. These models include the linear Glauber model, the Glauber-Ising model, lattice models with absorbing states such as the contact process and those used in population dynamic and spreading of epidemic, probabilistic cellular automata, reaction-diffusion processes, random sequential adsorption and dynamic percolation. A stochastic approach to chemical reaction is also presented.The textbook is intended for students of ...

  18. Extended Irreversible Thermodynamics

    CERN Document Server

    Jou, David

    2010-01-01

    This is the 4th edition of the highly acclaimed monograph on Extended Irreversible Thermodynamics, a theory that goes beyond the classical theory of irreversible processes. In contrast to the classical approach, the basic variables describing the system are complemented by non-equilibrium quantities. The claims made for extended thermodynamics are confirmed by the kinetic theory of gases and statistical mechanics. The book covers a wide spectrum of applications, and also contains a thorough discussion of the foundations and the scope of the current theories on non-equilibrium thermodynamics. For this new edition, the authors critically revised existing material while taking into account the most recent developments in fast moving fields such as heat transport in micro- and nanosystems or fast solidification fronts in materials sciences. Several fundamental chapters have been revisited emphasizing physics and applications over mathematical derivations. Also, fundamental questions on the definition of non-equil...

  19. CT and MR Imagings of Semicircular Canal Aplasia

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chung Hee; Hong, Hyun Sook; Yi, Beom Ha; Cha, Jang Gyu; Park, Seong Jin; Kim, Dae Ho; Lee, Hae Kyung; Kim, Shi Chan [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2009-07-15

    To evaluate the clinical, CT and MR imaging findings of semicircular canal (SCC) aplasia and to evaluate if a correlation exists between these findings and the associated anomalies or syndromes. This study retrospectively reviewed the CT and MRI findings of five patients with SCC aplasia. The CT and MR findings were analyzed for SCC, direction of facial nerve canal, cochlea, vestibule, oval or round window, middle ear ossicles, and internal auditory canal (IAC). The subjects included three boys and two girls ranging in age from one to 120 months (mean age; 51 months). Four of the subjects had the CHARGE syndrome, and one had the Goldenhar syndrome. Moreover, four subjects had sensorineural hearing loss and one had combined hearing loss. The course of the facial nerve canal was abnormal in all five cases. Moreover, trapped cochlea and dysplastic modiolus were each observed in one case. Four subjects had atresia of the oval window; whereas ankylosis of the ossicles was present in three subjects. IAC stenosis was present in one patient with the CHARGE syndrome. The aberrant course of the facial nerve canal, atresia of the oval window, and abnormal ossicles were frequently associated in patients with SCC aplasia. In addition, the Goldenhar and CHARGE syndromes were also commonly associated syndromes.

  20. Rational management approach to pure red cell aplasia.

    Science.gov (United States)

    Balasubramanian, Suresh Kumar; Sadaps, Meena; Thota, Swapna; Aly, Mai; Przychodzen, Bartlomiej P; Hirsch, Cassandra M; Visconte, Valeria; Radivoyevitch, Tomas; Maciejewski, Jaroslaw P

    2018-02-01

    Pure red cell aplasia is an orphan disease, and as such lacks rationally established standard therapies. Most cases are idiopathic; a subset is antibody-mediated. There is overlap between idiopathic cases and those with T-cell large granular lymphocytic leukemia, hypogammaglobulinemia, and low-grade lymphomas. In each of the aforementioned, the pathogenetic mechanisms may involve autoreactive cytotoxic responses. We selected 62 uniformly diagnosed pure red cell aplasia patients and analyzed their pathophysiologic features and responsiveness to rationally applied first-line and salvage therapies in order to propose diagnostic and therapeutic algorithms that may be helpful in guiding the management of prospective patients, 52% of whom were idiopathic, while the others involved large granular lymphocytic leukemia, thymoma, and B-cell dyscrasia. T-cell-mediated responses ranged between a continuum from polyclonal to monoclonal (as seen in large granular lymphocytic leukemia). During a median observation period of 40 months, patients received a median of two different therapies to achieve remission. Frequently used therapy included calcineurin-inhibitors with a steroid taper yielding a first-line overall response rate of 76% (53/70). Oral cyclophosphamide showed activity, albeit lower than that produced by cyclosporine. Intravenous immunoglobulins were effective both in parvovirus patients and in hypogammaglobulinemia cases. In salvage settings, alemtuzumab is active, particularly in large granular lymphocytic leukemia-associated cases. Other potentially useful salvage options include rituximab, anti-thymocyte globulin and bortezomib. The workup of acquired pure red cell aplasia should include investigations of common pathological associations. Most effective therapies are directed against T-cell-mediated immunity, and therapeutic choices need to account for associated conditions that may help in choosing alternative salvage agents, such as intravenous immunoglobulin

  1. Aplasia pulmonar: a propósito de dos casos

    Directory of Open Access Journals (Sweden)

    Augusto Ignacio Siegert-Olivares

    2015-01-01

    Conclusiones: La aplasia pulmonar es una entidad infrecuente. Debido a la variabilidad en la presentación clínica debe tenerse un alto índice de sospecha ante el hallazgo de la radiopacidad total del hemitórax. Los métodos diagnósticos que se utilizan son radiografía, tomografía y gammagrafía. Para confirmar el diagnóstico se requiere realizar broncoscopia. La escisión del muñón y la traslocación diafragmática se han descrito como opciones quirúrgicas de tratamiento.

  2. Nonequilibrium and irreversibility

    CERN Document Server

    Gallavotti, Giovanni

    2014-01-01

    This book concentrates on the properties of the stationary states in chaotic systems of particles or fluids, leaving aside the theory of the way they can be reached. The stationary states of particles or of fluids (understood as probability distributions on microscopic configurations or on the fields describing continua) have received important new ideas and data from numerical simulations and reviews are needed. The starting point is to find out which time invariant distributions come into play in physics. A special feature of this book is the historical approach. To identify the problems the author analyzes the papers of the founding fathers Boltzmann, Clausius and Maxwell including translations of the relevant (parts of ) historical documents. He also establishes a close link between treatment of irreversible phenomena in statistical mechanics and the theory of chaotic systems at and beyond the onset of turbulence as developed by Sinai, Ruelle, Bowen (SRB) and others: the author gives arguments intending t...

  3. Pure red cell aplasia following thymothymectomy: a case report.

    Science.gov (United States)

    Ck Rao, Anuradha; Nayal, Bhavna; Manohar, Chethan

    2013-10-01

    Thymoma, a rare epithelial neoplasm, is the most common anterior-superior mediastinal tumour. Thymoma can occur sporadically or in association with other conditions, such as myasthenia gravis, pure red cell aplasia (PRCA), and hypogammaglobulinemia. Only 5% of thymoma cases develop PRCA; however, 10-50% of patients presenting with PRCA have an associated spindle cell type thymoma. Thymoma complicated by PRCA is associated with a poor outcome. We report the case of a 38-year-old female who presented with chest pain, and was diagnosed with an anterior mediastinal mass. A thymectomy was performed, and histopathological examination revealed mixed thymoma; two months later, the patient developed PRCA. The present case reinforces the need for clinicians to be vigilant with thymoma patients, even following thymectomy.

  4. Pure red cell aplasia in a simultaneous pancreas-kidney transplantation patient: inside the erythroblast

    Directory of Open Access Journals (Sweden)

    Francesca Labbadia

    2012-09-01

    Full Text Available A case of pure red cell aplasia in a simultaneous kidney-pancreas transplant recipient on immunosuppressive therapy is reported here. The patient presented with anemia unresponsive to erythropoietin treatment. Bone marrow cytomorphology was highly suggestive of parvovirus pure red cell aplasia, which was confirmed with serology and polymerase chain reaction positive for parvovirus B19 DNA in peripheral blood. After the administration of intravenous immunoglobulin the anemia improved with a rising number of the reticulocytes.

  5. A Patient with Unilateral Tibial Aplasia and Accessory Scrotum: A Pure Coincidence or Nonfortuitous Association?

    Directory of Open Access Journals (Sweden)

    Zoran Gucev

    2010-01-01

    Full Text Available Tibial aplasia is an uncommon lower limb malformation that can occur isolated or be part of a more complex malformation pattern. We describe a 9-year-old boy born after uneventful pregnancy and delivery. Family history was negative for maternal diabetes and other malformations. The patient presented with left tibial aplasia and homolateral prexial foot polydactyly. He also displayed enamel dysplasia and bifid scotum with cryptorchidism. Literature review failed to identify a significant syndromic association between lower limb defects of the tibial type and the genital anomalies reported here. The combination of tibial aplasia with midline genital malformations further supports the hypothesis that the tibial ray development mirrors the morphogenetic process of the radial structures. Accordingly, the malformation pattern observed in the present patient may be pathogenetically explained by an insult occurring during late blastogenesis.

  6. Flow cytometric of reticulocytes quantification: radio-induction medullary aplasia application

    International Nuclear Information System (INIS)

    Dubner, D.; Perez, M.; Gisone, P.

    1996-01-01

    Flow cytometric reticulocyte quantification was assayed in ten patients undergoing bone marrow transplantation (BMT) with previous conditioning by chemotherapy and total body irradiation. A reticulocyte maturity index (RMI) was determined taking into account the RNA content. With the aim of testing the utility of RMI as an early predictor of functional recovery in marrow aplasia, other hematological indicators as neutrophils count were comparatively evaluated. Mean time elapsed between BMT and engraftment evidence by RMI was 17,6 days. In six patients the RMI was the earliest indicator of functional recovery. The applicability of this assay in the pursuit of radioinduced bone marrow aplasia is discussed. (authors). 4 refs., 4 figs., 2 tabs

  7. Chronic renal failure due to unilateral renal agenesis and total renal dysplasia (=aplasia)

    International Nuclear Information System (INIS)

    Kroepelin, T.; Ziupa, J.; Wimmer, B.

    1983-01-01

    Three adult patients with unilateral renal agenesis/total dysplasia (= aplasia) and with an early chronic renal failure are presented. One patient had renal agenesis without ureter bud and ureteric ostium on one side, and reflux pyelonephritis on the other; one had small compact total renal dysplasia (= aplasia) on one side, while chronic uric acid nephropathy (chronic renal disease as a cause of gout) was diagnosed on the other; the third patient had a total large multicystic dysplasia on one side, and on the other a segmental large multicystic dysplasia. Radiological steps and radiodiagnostic criteria are discussed and the combination of urogenital and extraurogenital anomalies is referred to. (orig.)

  8. Aplasia Cutis Congénita: Presentación de un caso

    OpenAIRE

    Rosa María Alonso Uría; Irka Ballesté López

    1998-01-01

    Se reportó el caso de un recién nacido, hijo de madre secundigesta, con una malformación congénita del cuero cabelludo, del tipo aplasia cutis congénita. Se describieron las características clínicas de ésta, su evolución, pronóstico y tratamiento. Se hizo énfasis en el cuidado y la prevención de las complicaciones, fundamentalmente infecciosas, en este tipo de neonatosThe case of a newborn, son of a secundigravida, with a congenital malformation of the scalp denominated aplasia cutis congenit...

  9. Cyclosporin A Reversed Chemoresistance of a Patient with Pure Red Cell Aplasia Secondary to Thymoma.

    Science.gov (United States)

    Li, Peng; Du, Fengcai; Gong, Zhaohua; Hu, Baohong; Chi, Cheng; Chu, Hongjin; Chen, Jian

    2017-08-01

    This case study reports on a patient who relapsed with thymoma (mixed type) nine years after tumor resection. After four courses of rescue chemotherapy (docetaxel and cisplatinum), the patient was further diagnosed with pure red cell aplasia. It was noticed that cyclosporin A (CsA), which was administered to treat aplasia, could reverse chemoresistance. Its mechanism is not completely clear, but the hypothesis of CsA inhibiting P-glycoprotein mediated drug efflux is the most acceptable. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  10. Reticulocyte maturity index by flow cytometry: its applicability in radioinduced bone marrow aplasia

    International Nuclear Information System (INIS)

    Dubner, D.; Gisone, P.; Perez, M.R.

    1995-01-01

    Flow cytometric reticulocyte quantification was assayed in ten patients undergoing bone marrow transplantation (BMT) with previous conditioning chemotherapy and total body irradiation (TBI). A reticulocyte maturity index (RMI) was determined taking into account the RNA content. With de aim of testing the utility of RMI as an early predictor of functional recovery in marrow aplasia, other haematological indicators as neutrophils count were comparatively evaluated. Mean time elapsed between BMT and engraftment evidence by RMI was 17,6 days. In six patients the RMI was the earliest indicator of functional recovery. The applicability of this assay in the following of radioinduced bone marrow aplasia is discussed. (author). 4 refs., 4 figs., 2 tabs

  11. Global Warming, Irreversibility and Learning.

    OpenAIRE

    Ulph, Alistair; Ulph, David

    1997-01-01

    A number of economists have argued that the literature on the irreversibility effect implies that current abatement of greenhouse gas emissions should be greater when there is the possibility of obtaining better information in the future about the potential damages from global warming than when there is no possibility of obtaining better information. In this paper the authors show that even the simplest model of global warming does not satisfy either of Epstein's (1980) sufficient conditions,...

  12. Extremum principles for irreversible processes

    International Nuclear Information System (INIS)

    Hillert, M.; Agren, J.

    2006-01-01

    Hamilton's extremum principle is a powerful mathematical tool in classical mechanics. Onsager's extremum principle may play a similar role in irreversible thermodynamics and may also become a valuable tool. His principle may formally be regarded as a principle of maximum rate of entropy production but does not have a clear physical interpretation. Prigogine's principle of minimum rate of entropy production has a physical interpretation when it applies, but is not strictly valid except for a very special case

  13. Ecological optimization for generalized irreversible Carnot refrigerators

    Science.gov (United States)

    Chen, Lingen; Xiaoqin, Zhu; Sun, Fengrui; Wu, Chih

    2005-01-01

    The optimal ecological performance of a Newton's law generalized irreversible Carnot refrigerator with the losses of heat resistance, heat leakage and internal irreversibility is derived by taking an ecological optimization criterion as the objective, which consists of maximizing a function representing the best compromise between the exergy output rate and exergy loss rate (entropy production rate) of the refrigerator. Numerical examples are given to show the effects of heat leakage and internal irreversibility on the optimal performance of generalized irreversible refrigerators.

  14. Aplasia of the arteria carotis interna in a male patient with congenital myotonia

    International Nuclear Information System (INIS)

    Sakellariou, P.; Schirmer, M.; Seibert, H.

    1980-01-01

    In a 54 years old man who suffered from a myotonia congenita an intracranial aneurysm was suspected. Cerebral angiography revealed an aplasia of the left internal carotid artery. This very rate anomaly has not yet been described together with a myotonia congenita. (orig.) [de

  15. Aplasia cutis congenita er en sjælden og mulig overset kongenit anomali

    DEFF Research Database (Denmark)

    E Rogvi, Rasmus; Sommerlund, Mette; Vestergaard, Esben Thyssen

    2014-01-01

    Aplasia cutis congenita (ACC) is a rare congenital defect of the skin. In this study we present the diagnosis and management of the condition. In 1997-2009 a total of 65 ACC cases were registered in the Danish National Patient Registry (1:13.000 births). The mortality among these cases was 1...

  16. Sebaceous nevus syndrome, central nervous system malformations, aplasia cutis congenita, limbal dermoid, and pigmented nevus syndrome.

    Science.gov (United States)

    Hsieh, Chih-Wei; Wu, Yu-Hung; Lin, Shuan-Pei; Peng, Chun-Chih; Ho, Che-Sheng

    2012-01-01

    SCALP syndrome is an acronym describing the coincidence of sebaceous nevus syndrome, central nervous system malformations, aplasia cutis congenita, limbal dermoid, and pigmented nevus (giant congenital melanocytic nevus). We present a fourth case of this syndrome. © 2012 Wiley Periodicals, Inc.

  17. Extensive Intracranial Arteriovenous Malformation in a Child with Aplasia Cutis Congenita.

    Science.gov (United States)

    Gómez, María; Chiesura, Vilma; Noguera-Morel, Lucero; Hernández-Martín, Angela; García-Peñas, Juan José; Torrelo, Antonio

    2015-01-01

    We report on a child with multiple lesions of membranous aplasia cutis congenita of the scalp since birth who developed an extensive intracranial arteriovenous malformation several years later. Even in the absence of other clues to suggest intracranial anomalies, children with multiple scalp defects should be carefully surveyed and followed up in the long term. © 2015 Wiley Periodicals, Inc.

  18. Reconstruction of bilateral tibial aplasia and split hand-foot syndrome in a father and daughter

    Directory of Open Access Journals (Sweden)

    Ali Al Kaissi

    2014-01-01

    Full Text Available Background: Tibial aplasia is of heterogeneous aetiology, the majority of reports are sporadic. We describe the reconstruction procedures in two subjects - a daughter and father manifested autosomal dominant (AD inheritance of the bilateral tibial aplasia and split hand-foot syndrome. Materials and Methods: Reconstruction of these patients required multiple surgical procedures and orthoprosthesis was mandatory. The main goal of treatment was to achieve walking. Stabilization of the ankle joint by fibular-talar-chondrodesis on both sides, followed by bilateral Brown-procedure at the knee joint level has been applied accordingly. Results: The outcome was with improved function of the deformed limbs and walking was achieved with simultaneous designation of orthotic fitting. Conclusion: This is the first study encompassing the diagnosis and management of a father and daughter with bilateral tibial aplasia associated with variable split hand/foot deformity without foot ablation. Our patients showed the typical AD pattern of inheritance of split-hand/foot and tibial aplasia.

  19. [Bilateral deep venous thrombosis and vena cava aplasia treated with local thrombolysis

    DEFF Research Database (Denmark)

    Pelta, A.M.; Jørgensen, Maja; Just, Sven Richardt Lundgren

    2008-01-01

    In this case report the treatment of a young man with bilateral iliaco-femoral DVT and vena cava aplasia is presented. The patient was treated with catheter-directed thrombolysis; the catheters were introduced in the thrombus of both legs via v. popliteae. The treatment led to almost complete...

  20. Antibiotic use for irreversible pulpitis.

    Science.gov (United States)

    Agnihotry, Anirudha; Fedorowicz, Zbys; van Zuuren, Esther J; Farman, Allan G; Al-Langawi, Jassim Hasan

    2016-02-17

    Irreversible pulpitis, which is characterised by acute and intense pain, is one of the most frequent reasons that patients attend for emergency dental care. Apart from removal of the tooth, the customary way of relieving the pain of irreversible pulpitis is by drilling into the tooth, removing the inflamed pulp (nerve) and cleaning the root canal. However, a significant number of dentists continue to prescribe antibiotics to stop the pain of irreversible pulpitis.This review updates the previous version published in 2013. To assess the effects of systemic antibiotics for irreversible pulpitis. We searched the Cochrane Oral Health Group's Trials Register (to 27 January 2016); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 12); MEDLINE via Ovid (1946 to 27 January 2016); EMBASE via Ovid (1980 to 27 January 2016), ClinicalTrials.gov (to 27 January 2016) and the WHO International Clinical Trials Registry Platform (to 27 January 2016). There were no language restrictions in the searches of the electronic databases. Randomised controlled trials which compared pain relief with systemic antibiotics and analgesics, against placebo and analgesics in the acute preoperative phase of irreversible pulpitis. Two review authors screened studies and extracted data independently. We assessed the quality of the evidence of included studies using GRADEpro software. Pooling of data was not possible and a descriptive summary is presented. One trial assessed at low risk of bias, involving 40 participants was included in this update of the review. The quality of the body of evidence was rated low for the different outcomes. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the seven-day study period. There was insufficient evidence to claim or refute a benefit for penicillin for pain intensity. There was no significant difference in the mean total number of ibuprofen tablets over the

  1. Bullous aplasia cutis congenita: Case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Maria Teresa Garcia-Romero

    2011-01-01

    Full Text Available Aplasia cutis congenita is a rare condition characterized by the absence of skin and sometimes other underlying structures such as bone or dura. It can be a part of various syndromes and can be associated with multiple genetic diseases, malformation patterns, or a combination of all. It is even considered as a form frustre of a neural tube defect in several literatures. Bullous aplasia cutis congenita is a clinical subtype of the condition, with extremely few cases reported in the literature. It presents as a cystic or bullous lesion at birth, which eventually transforms into an atrophic, flat scar covered by a thin epithelium. Some cases present with a dark collar hair sign around the lesion, which can be even more indicative of an underlying neural tube defect. Management remains controversial and depends on the characteristics of the lesion, but conservative treatment is usually chosen.

  2. Aplasia Cutis Congénita: Presentación de un caso

    Directory of Open Access Journals (Sweden)

    Rosa María Alonso Uría

    1998-06-01

    Full Text Available Se reportó el caso de un recién nacido, hijo de madre secundigesta, con una malformación congénita del cuero cabelludo, del tipo aplasia cutis congénita. Se describieron las características clínicas de ésta, su evolución, pronóstico y tratamiento. Se hizo énfasis en el cuidado y la prevención de las complicaciones, fundamentalmente infecciosas, en este tipo de neonatosThe case of a newborn, son of a secundigravida, with a congenital malformation of the scalp denominated aplasia cutis congenita is reported. Its clinical characteristics, evolutions, prognosis and treatment are described. Emphasis is made on the care and prevention of the complications, mainly infectious, in this type of neonates

  3. The prevalence of frontal sinus aplasia in Mashhad, Northeast of Iran

    Directory of Open Access Journals (Sweden)

    Masoud Pezeshki Rad

    2009-04-01

    Full Text Available Introduction: There are various reports of the prevalence of frontal sinus aplasia in different geographical areas and ethnic origins. The size and shape of frontal sinus is different among various populations. This study used CT scan images to investigate the frequency of absence of frontal sinuses in adults of northeastern Iran. Materials and Methods: The present study was performed retrospectively on the axial and coronal CT scans of the paranasal sinuses from a series of 588 patients who had referred to CT scan ward of Mashhad Imam Reza hospital without any other sinus pathology. Results: The mean age of patients was 44.39± 19.44 years. Unilateral and bilateral aplasia of frontal sinuses was seen in 36 and 51 patients, respectively. The dominant sinus was in the left side in 68.24% of cases. Conclusion: The lower incidence of frontal sinus aplasia in this particular ethnic and geographical area relative to other populations emphasizes the effect of environmental and genetic factors on the development of frontal sinuses.  

  4. Congenital diaphragmatic hernia with concurrent aplasia of the pericardium in a foal.

    Science.gov (United States)

    Tăbăran, Alexandru-Flaviu; Nagy, Andras Laszlo; Cătoi, Cornel; Morar, Iancu; Tăbăran, Alexandra; Mihaiu, Marian; Bolfa, Pompei

    2015-12-30

    In veterinary medicine congenital abnormalities of the diaphragm and pericardium are rare, idiopathic malformations, being reported mainly in dogs. This report documents an unusual case of developmental defects in a foal consisting of diaphragmatic hernia concurrent with pericardial aplasia. Following a normal delivery, a full term, female Friesian stillborn foal with the placenta was presented for necropsy. External morphological examination indicated a normally developed foal. At necropsy, a large oval defect (approximately 20 × 15 cm in size) was observed in the left-dorsal side of the diaphragm (left lumbocostal triangle). This defect allowed the intestinal loops, spleen and partially the liver to translocate into the thorax. The loops of the left ascending colon, including the pelvic flexure and partially the small intestine covered the cranial and dorsal posterior parts of the heart due to the complete absence of the left pericardium. The remaining pericardium presented as a white, semi-transparent strip, partially covering the right side of the heart. The left lung and the main bronchus were severely hypoplastic to approximately one-fifth the size of their right homologue. The intermediate part of the liver, containing mainly the enlarged quadrate lobe was translocated in the thorax, severely enlarged and showed marked fibrosis. Histologically in the herniated lobes we diagnosed hepatic chronic passive congestion, telangiectasia and medial hypertrophy of blood vessels. Concomitant malformation involving diaphragmatic hernia and pericardial aplasia in horses have not been previously reported. Moreover, this is the first case describing pericardial aplasia in horse.

  5. [Risk factors for teeth aplasia and hypoplasia in cleft lip and palate children].

    Science.gov (United States)

    Korolenkova, M V; Starikova, N V; Ageeva, L V

    2016-01-01

    The aim of the study was to assess the significance of environmental risk factors for teeth aplasia and hypoplasia in cleft lip and palate children. Two hundred and forty-seven cleft lip and palate (CLP) children were enrolled in the study including 105 (42.5%) with bilateral CLP and 57.5% with unilateral CLP. The mean age was 11.2±4.9 years. Teeth condition was assessed clinically and radiologically. The impact of risk factors for teeth anomalies was analyzed by retrospective data obtained from computer database (absence of preoperative orthopedic treatment, palatal defects after primary palatoplasty and type of primary procedures). Surgical trauma by early periosteoplasty (at the age of 3-4 months), excessive scarring and tissue traction due to absence of early orthopedic treatment and palatal defect were associated with significantly higher incidence of incisors hypoplasia (both developmental enamel defects and microdentia) and aplasia of central incisors not seen in the other study subgroups. Incisors aplasia and hypoplasia in CLP patients do not always have disembryogenic origin but may depend on external environmental factors, including surgical trauma.

  6. Anomalies, Unitarity and Quantum Irreversibility

    CERN Document Server

    Anselmi, D

    1999-01-01

    The trace anomaly in external gravity is the sum of three terms at criticality: the square of the Weyl tensor, the Euler density and Box R, with coefficients, properly normalized, called c, a and a', the latter being ambiguously defined by an additive constant. Unitarity and positivity properties of the induced actions allow us to show that the total RG flows of a and a' are equal and therefore the a'-ambiguity can be consistently removed through the identification a'=a. The picture that emerges clarifies several long-standing issues. The interplay between unitarity and renormalization implies that the flux of the renormalization group is irreversible. A monotonically decreasing a-function interpolating between the appropriate values is naturally provided by a'. The total a-flow is expressed non-perturbatively as the invariant (i.e. scheme-independent) area of the graph of the beta function between the fixed points. We test this prediction to the fourth loop order in perturbation theory, in QCD with Nf ~< ...

  7. Quantum nonequilibrium equalities with absolute irreversibility

    Science.gov (United States)

    Funo, Ken; Murashita, Yûto; Ueda, Masahito

    2015-07-01

    We derive quantum nonequilibrium equalities in absolutely irreversible processes. Here by absolute irreversibility we mean that in the backward process the density matrix does not return to the subspace spanned by those eigenvectors that have nonzero weight in the initial density matrix. Since the initial state of a memory and the postmeasurement state of the system are usually restricted to a subspace, absolute irreversibility occurs during the measurement and feedback processes. An additional entropy produced in absolutely irreversible processes needs to be taken into account to derive nonequilibrium equalities. We discuss a model of a feedback control on a qubit system to illustrate the obtained equalities. By introducing N heat baths each composed of a qubit and letting them interact with the system, we show how the entropy reduction via feedback control can be converted into work. An explicit form of extractable work in the presence of absolute irreversibility is given.

  8. Successful pulpal anesthesia for symptomatic irreversible pulpitis.

    Science.gov (United States)

    Drum, Melissa; Reader, Al; Nusstein, John; Fowler, Sara

    2017-04-01

    Profound pulpal anesthesia after a successful inferior alveolar nerve block can be difficult to achieve when the clinical condition is a pulpal diagnosis of symptomatic irreversible pulpitis. The authors reviewed the literature as it relates to the anesthesia necessary for endodontic therapy of patients with painful, vital, mandibular teeth diagnosed with symptomatic irreversible pulpitis. Supplemental anesthetic techniques and medications are available that can be used to improve pulpal anesthesia for patients with the clinical condition of symptomatic irreversible pulpitis. The authors identified treatment recommendations for anesthesia in the case of symptomatic irreversible pulpitis based on a review of the available evidence. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

  9. Uterovaginal Anastomosis for Cases of Cryptomenorrhea Due to Cervical Atresia with Vaginal Aplasia: Benefits and Risks.

    Science.gov (United States)

    Zayed, M; Fouad, R; Elsetohy, K A; Hashem, A T; AbdAllah, A A; Fathi, A I

    2017-12-01

    The objective of this study was to assess short-term benefits and risks of utero-vaginal anastomosis done for cases of cryptomenorrhea due to cervical atresia with vaginal aplasia. Prospective study. Surgical procedures were done between December 2013 and September 2015 at the department of Obstetrics and Gynecology, Cairo University Hospital. Five patients who had cryptomenorrhea due to cervical atresia associated with vaginal aplasia were included. Utero-vaginal anastomoses were performed in 2 stages; a stage of McIndoe vaginoplasty and a stage of excision of the atretic cervical tissue and anastomosing the uterus to the neovagina. Follow-up was done by gynecological and ultrasound examination in a duration ranged from 12 to 36 months. Occurrence of regular menstrual flow and relief of the severe cyclic pain. All patients had relief of the severe cyclic pain. Four patients had regular menstrual flow. One patient developed occlusion of the track after 1 year and needed dilatation once. Three patients developed low vaginal stenosis without occlusion of the track. One patient had rectal injury repaired without causing postoperative morbidity. Uterovaginal anastomosis is a promising conservative management option for cervical atresia with vaginal aplasia, which has benefits but is not free of risks. Long-term follow-up is still needed to judge its feasibility. We recommend performing McIndoe vaginoplasty as a starting stage before the anastomosis preferably in a separate setting. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  10. APLASIA CUTIS CONGÉNITA – UM CASO CLÍNICO

    Directory of Open Access Journals (Sweden)

    Mónica Costeira

    2016-07-01

    Comentários: A aplasia cutis congénita é uma lesão que pode ser causadora de grande ansiedade parental, pelo que é importante ao Pediatra o seu reconhecimento e devido esclarecimento. Apesar de se tratar, na maioria das vezes, de um defeito benigno, é importante o conhecimento da sua relação com outras anomalias e síndromes de forma a otimizar a sua orientação precoce e adequada. Da mesma forma, é importante o aconselhamento genético, nos casos que assim o justifiquem.

  11. Aplasia cutis congenita associated with type I split cord malformation: Unusual case

    OpenAIRE

    Bashar Abuzayed; Pamir Erdincler

    2014-01-01

    A full-term newborn girl born with large skin, muscle, bone and dural defect in the lumbo-sacral area. The lesion included a split spinal cord by a perpendicular bony spur and connected from its tip to the upper lamina. Patient was diagnosed with aplasia cutis congenita (ACC) associated with type I split cord malformation (SCM). Neurological examination of the lower extremities was normal. Spinal X-rays showed a bony spur on the L2 vertebral column and laminar defect in the lumbo-sacral area....

  12. Aplasia cutis congenita associated with type I split cord malformation: Unusual case.

    Science.gov (United States)

    Abuzayed, Bashar; Erdincler, Pamir

    2014-01-01

    A full-term newborn girl born with large skin, muscle, bone and dural defect in the lumbo-sacral area. The lesion included a split spinal cord by a perpendicular bony spur and connected from its tip to the upper lamina. Patient was diagnosed with aplasia cutis congenita (ACC) associated with type I split cord malformation (SCM). Neurological examination of the lower extremities was normal. Spinal X-rays showed a bony spur on the L2 vertebral column and laminar defect in the lumbo-sacral area. Lesion was operated and closed according to anatomic layers. Clinical and intraoperative findings of this extremely rare case are discussed.

  13. Adrenal and renal corticomedullary junction iron deposition in red cell aplasia

    Energy Technology Data Exchange (ETDEWEB)

    Rakow-Penner, Rebecca; Vasanawala, Shreyas [Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States); Glader, Bert [Stanford University School of Medicine, Department of Pediatric Hematology and Oncology, Stanford, CA (United States); Yu, Huanzhou [Global MR Applied Science Lab, GE Healthcare, Menlo Park, CA (United States)

    2010-12-15

    Iron deposition can occur in the kidneys as a result of hemolysis or extensive iron overload from transfusions. With T2* MRI, renal iron deposition can be visualized. In this report, renal corticomedullary junction iron deposition is noted using T2* MRI in a boy with red cell aplasia. The renal corticomedullary junction iron deposition is an indication of the severity of his iron overload. This is an unusual finding and brings clinical attention to the boy's renal function for further evaluation. (orig.)

  14. Pure Red Cell Aplasia and Hypogammaglobulinemia in a Patient with Thymoma

    Directory of Open Access Journals (Sweden)

    Chen-Sung Lin

    2009-01-01

    Full Text Available Both pure red cell aplasia (PRCA and hypogammaglobulinemia are rarer conditions than myasthenia gravis (MG in thymoma patients. Several articles have discussed the relation between PRCA and thymoma or hypogammaglobulinemia and thymoma, and their proper treatments. Instances of both PRCA and hypogammaglobulinemia in a thymoma patient are few and reported sporadically in the literature. We discuss a 46-year-old woman with thymoma and simultaneous PRCA and hypogammaglobulinemia who achieved complete remission from PRCA after perioperative steroid administration and extended thymectomy, and review the literature.

  15. Fundamental optimal relation of a generalized irreversible Carnot ...

    Indian Academy of Sciences (India)

    The generalized irreversible Carnot heat pump model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat leakage, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities besides heat resistance are characterized by a constant parameter and a ...

  16. Bilateral posterior semicircular canal aplasia and atypical paroxysmal positional vertigo: a case report

    Science.gov (United States)

    Walther, LE; Nath, V; Krombach, GA; Di Martino, E

    2008-01-01

    Summary Isolated congenital malformations of semicircular canals are rare abnormalities. Most inner ear abnormalities occur in syndromes and are associated with hearing loss. Unilateral or bilateral single aplasia of one semicircular canal does not usually result in vertigo, but these become clinically important if there are clinical complaints of vertigo. Computed tomography imaging and high resolution magnetic resonance imaging may reveal inner ear abnormalities. The case is presented here of a 46-year-old male with a 10-year history of recurrent positional vertigo with strong onset when changing position to the left side. Magnetic resonance imaging of the inner ear showed a bilateral posterior semicircular canal aplasia as well as an enlarged vestibule on both sides. Dix-Hallpike positional manoeuvre revealed a positional nystagmus in the left head-hanging position of short duration and latency of a few seconds. When rising, vertigo occurred, but no nystagmus was visible. The fast phase of the nystagmus was mainly vertical down-beating with a slight torsional component to the uppermost ear. Although benign paroxysmal vertigo of the anterior canal was suspected, physical therapy was not effective using a modified liberatory manoeuvre. Brandt-Daroff therapy was effective permanently. PMID:18669072

  17. Aplasia cutis congenita: Two case reports and discussion of the literature

    Science.gov (United States)

    Alexandros, Blionas; Dimitrios, Giakoumettis; Elias, Antoniades; Evangelos, Drosos; Andreas, Mitsios; Sotirios, Plakas; Georgios, Sfakianos; Marios, Themistocleous S.

    2017-01-01

    Background: Aplasia cutis congenita (ACC) is a part of a heterogeneous group of conditions characterized by the congenital absence of epidermis, dermis, and in some cases, subcutaneous tissues or bone usually involving the scalp vertex. There is an estimated incidence of 3 in 10,000 births resulting in a total number of 500 reported cases to date. The lesions may occur on every body surface although localized scalp lesions form the most frequent pattern (70%). Complete aplasia involving bone defects occurs in approximately 20% of cases. ACC can occur as an isolated defect or can be associated with a number of other congenital anomalies such as limb anomalies or embryologic malformations. In patients with large scalp and skull defects, there is increased risk of infection and bleeding along with increased mortality and therefore prompt and effective management is advised. Case Description: We describe two cases of ACC, involving a 4 × 3 cm defect managed conservatively and a larger 10 × 5 cm defect managed surgically with the use of a temporo-occipital scalp flap. Both cases had an excellent outcome. Conclusions: Multiple treatment regimens exist for ACC, but there is no consensus on treatment strategies. Conservative treatment has been described and advocated, but many authors have emphasized the disadvantages of this treatment modality. Decision between conservative and surgical management must be individualized according to lesion size and location. PMID:29204308

  18. Routine treatment of bilateral aplasia of upper lateral incisors by orthodontic space closure without mandibular extractions.

    Science.gov (United States)

    Zimmer, Bernd; Seifi-Shirvandeh, Nasrin

    2009-06-01

    This study aimed to gather statistically validated information on the changes in orthodontic variables in patients with bilateral upper lateral incisor aplasia treated with isolated orthodontic space closure. Data were collected from 25 (15 females, 10 males) consecutively treated, unselected adolescents [mean age at the end of treatment 16.4 years, standard deviation (SD) 1.3] after orthodontic space closure using push-and-pull mechanics (PPM). The changes in the relevant parameters were determined by comparing baseline and final lateral headfilms and casts. Following verification of normal distribution by means of a Kolmogorov-Smirnov test, a two-tailed t-test for related data was performed. SNA, ANB, OcP-NL, OcP-ML, upper space balance, overbite, overjet, bilateral molar relationship, and L1-NB changed significantly (P orthodontic space closure for bilateral upper lateral incisor aplasia using PPM can be regarded as a valid alternative to prosthetic solutions. Long-term use of Class III elastics does not lead to significant changes in relevant orthodontic parameters.

  19. [Postpartum parvovirus B19-associated acute pure red cell aplasia and hemophagocytic syndrome].

    Science.gov (United States)

    Tsuda, H; Shirono, K; Shimizu, K; Shimomura, T

    1995-07-01

    A 30-year-old postpartum woman was admitted to our hospital because of progressive anemia, malaise, night sweating, headache and low grade fever which began 9 days after delivery (day 0). She had normocytic hypochromic anemia accompanied with marked decrease in reticulocytes. In addition, a temporary decrease in platelets and white blood cells especially neutrophils were observed. Bone marrow smears showed an apparent decrease in erythroid cells and the presence of giant proerythroblasts (1.2%) as well as hemophagocytes (1.2%). IgM and IgG antibody against human parvovirus B19 (HPV) was detected on day 22 of the disease although negative results were obtained on day 3. The presence of the virus in the blood on admission was confirmed by dot-blot analysis. Thus, this case was diagnosed as acute pure red cell aplasia and hemophagocytic syndrome caused by HPV infection. This patient had been given iron for iron deficiency anemia before delivery and the iron deficiency was still present after the episode of the present disease although the iron metabolism data was perturbed during the disease. These findings suggest that HPV could cause acute pure red cell aplasia not only in patients with hemolytic anemia but also in patients with iron deficiency anemia or after acute bleeding. Furthermore it is suggested that pancytopenia often observed on HPV infection could be at least partly caused by hemophagocytic syndrome.

  20. Bacterial, fungal and yeast contamination in six brands of irreversible hydrocolloid impression materials Contaminação por bactérias, fungos e leveduras em seis marcas comerciais de materiais de moldagem à base de hidrocolóide irreversível

    OpenAIRE

    Luciana Assirati Casemiro; Carlos Henrique Gomes Martins; Fernanda de Carvalho Panzeri Pires de Souza; Heitor Panzeri; Isabel Yoko Ito

    2007-01-01

    This study assessed the level of contamination of six commercially available irreversible hydrocolloids (two containing chlorhexidine) and identified the contamination present in the materials. Petri dishes containing selective and enriched culture media were inoculated with alginate powder (0.06 g), in triplicate. After incubation (37°C/7 days), the colony-forming units (CFU) were counted and Gram stained. Biochemical identification of the different morphotypes was also performed. The co...

  1. Like Father, Like Daughter-inherited cutis aplasia occurring in a family with Marfan syndrome: a case report.

    Science.gov (United States)

    Islam, Yasmin Florence Khodeja; Williams, Charles A; Schoch, Jennifer Jane; Andrews, Israel David

    2017-01-01

    We present the case of a newborn with co-occurrence of Marfan syndrome and aplasia cutis congenita (ACC) and a family history significant for Marfan syndrome and ACC in the father. This case details a previously unreported mutation in Marfan syndrome and describes a novel coinheritance of Marfan syndrome and ACC.

  2. SCALP syndrome: sebaceous nevus syndrome, CNS malformations, aplasia cutis congenita, limbal dermoid, and pigmented nevus (giant congenital melanocytic nevus) with neurocutaneous melanosis: a distinct syndromic entity.

    Science.gov (United States)

    Lam, Joseph; Dohil, Magdalene A; Eichenfield, Lawrence F; Cunningham, Bari B

    2008-05-01

    Nevus sebaceus syndrome (SNS) is a constellation of nevus sebaceus with extracutaneous findings, including the ophthalmologic nervous, and musculoskeletal systems. Didymosis aplasticosebacea is a recently described entity consisting of aplasia cutis congenita and nevus sebaceus, implying twin spotting (didymosis). We describe a neonate with a nevus sebaceus on the scalp and a limbal dermoid on her left eye. Contiguous with the nevus sebaceus was a giant congenital melanocytic nevus and numerous areas of membranous aplasia cutis congenita. We propose the acronym SCALP (nevus sebaceus, central nervous system malformations, aplasia cutis congenita, limbal dermoid, pigmented nevus) to summarize the unique features of this case and review the two similar cases in the literature.

  3. Ultrafast irreversible phototautomerization of o-nitrobenzaldehyde.

    Science.gov (United States)

    Migani, Annapaola; Leyva, Verónica; Feixas, Ferran; Schmierer, Thomas; Gilch, Peter; Corral, Inés; González, Leticia; Blancafort, Lluís

    2011-06-14

    o-Nitrobenzaldehyde is photolabile because of an irreversible phototautomerization, whereas comparable aromatic compounds function as photoprotectors because the tautomerization is reversible. In this experimental and theoretical study we track down the cause of this difference to the electronic changes that occur during the tautomerization. This journal is © The Royal Society of Chemistry 2011

  4. A kinetic equation for irreversible aggregation

    International Nuclear Information System (INIS)

    Zanette, D.H.

    1990-09-01

    We introduce a kinetic equation for describing irreversible aggregation in the ballistic regime, including velocity distributions. The associated evolution for the macroscopic quantities is studied, and the general solution for Maxwell interaction models is obtained in the Fourier representation. (author). 23 refs

  5. Irreversibility and self-organization in spin glasses. 2. Irreversibility and the problem of configuration averaging

    International Nuclear Information System (INIS)

    Kovrov, V.P.; Kurbatov, A.M.

    1989-05-01

    The generalization of a configuration averaging to a system displaying irreversible effects is suggested. The properties of the ''pathological'' equilibrium state at low temperatures are determined and discussed. (author). 16 refs, 3 figs

  6. Aplasia cutis congenita of the scalp with large underlying skull defect: a case report

    International Nuclear Information System (INIS)

    Leboucq, N.; Montoya y Martinez, P.; Montoya-Vigo, F.; Castan, P.

    1994-01-01

    Localised agenesis of the scalp is the most frequent patern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20 % of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment. (orig.)

  7. Pure red-cell aplasia and autoimmune hemolytic anemia in a patient with acute hepatitis A.

    Science.gov (United States)

    Chang, Hyo Jeong; Sinn, Dong Hyun; Cho, Sung Gyun; Oh, Tae Hoon; Jeon, Tae Joo; Shin, Won Chang; Choi, Won Choong

    2014-06-01

    Pure red cell aplasia (PRCA) and autoimmune hemolytic anemia (AIHA) have rarely been reported as an extrahepatic manifestation of acute hepatitis A (AHA). We report herein a case of AHA complicated by both PRCA and AIHA. A 49-year-old female with a diagnosis of AHA presented with severe anemia (hemoglobin level, 6.9 g/dL) during her clinical course. A diagnostic workup revealed AIHA and PRCA as the cause of the anemia. The patient was treated with an initial transfusion and corticosteroid therapy. Her anemia and liver function test were completely recovered by 9 months after the initial presentation. We review the clinical features and therapeutic strategies for this rare case of extrahepatic manifestation of AHA.

  8. A novel mutation in IRF6 resulting in VWS-PPS spectrum disorder with renal aplasia.

    Science.gov (United States)

    de Medeiros, Filipe; Hansen, Lars; Mawlad, Evete; Eiberg, Hans; Asklund, Camilla; Tommerup, Niels; Jakobsen, Linda P

    2008-06-15

    Popliteal pterygium syndrome (PPS) and Van der Woude syndrome (VWS) are caused by mutations in the gene interferon regulatory factor 6 (IRF6). Skeletal, genital malformations and involvement of the skin occur in PPS and orofacial clefting and lip pits occur in both. We report on a patient with unilateral cleft lip and palate, ankyloblepharon, paramedian lip pits, unilateral renal aplasia, and a coronal hypospadias. By sequencing IRF6, we detected a novel missense mutation (Arg339Ile). The other family members were unaffected and had no IRF6 mutations, including the patient's brother who was also born with hypospadias. The patient and his brother were both conceived by in vitro fertilization (IVF). It is discussed whether the renal malformation in the patient is related to the IVF procedure or to the IRF6 mutation. 2008 Wiley-Liss, Inc.

  9. Transient pure red blood cell aplasia as clinical presentation of congenital hemolytic anemia: a case report.

    Science.gov (United States)

    Figueiredo, Sofia; Pio, Daniela; Martins, Margarida; Seabra, Carlos; Pinhal, Marisol; Parada, Arménia

    2009-06-17

    Hereditary elliptocytosis is a congenital hemolytic anemia characterized by the presence of oval shaped erythrocytes in the peripheral blood. In rare cases, transient pure red blood cell aplasia can be the initial clinical presentation.We report a case of a 27-month-old boy admitted with fever without focus, severe poikilocytic anemia, no evidence of hemolysis, a normocelular bone marrow and negative serological tests for viral infections. One month before admission, he had been treated with phenytoin and valproate after a seizure episode without fever.Analysis of red cell membrane proteins showed a 16% decrease in spectrin levels, also detected in his father and brother, confirming the diagnosis of elliptocytosis.Only his father carried the alpha(LELY) mutation, in trans to the alpha-spectrin mutation.

  10. [Thymoma with Pure Red Cell Aplasia;Report of a Case].

    Science.gov (United States)

    Hayakawa, Masanobu; Oda, Kazuyuki

    2017-09-01

    A thymoma with pure red cell aplasia (PRCA) is relatively rare. A 71-year-old woman complainted of dizziness and her blood cell count showed a severe anemia. She was diagnosed as PRCA by bone marrow aspiration biopsy, which showed marked decrease in number of erythroblasts. In addition, the chest computed tomography revealed a solid tumor in the anterior mediastinum. She underwent extended thymothymectomy through median sternotomy. The resected specimen was 10.5×9.7 cm in diameter. The pathological diagnosis was type AB thymoma of the World Health Organization classification, and Masaoka stage I. Ciclosporin was started to treat PRCA 3 months after the surgery, and she has been well for about 1 year after surgery without recurrence of thymoma or relapse of anemia.

  11. Diagnosis and treatment of thymoma associated with pure red cell aplasia: three cases report

    International Nuclear Information System (INIS)

    Wang Wencai; Xu Wuyin

    2000-01-01

    Objective: To discuss how to diagnose and treat thymoma associated with pure red cell aplasia (PRCA). Methods: Three patients of thymoma associated with PRCA were treated with thymothymectomy, and the local radiotherapy was conducted after operation for avoiding the thymoma reproduction. Determining of their peripheral blood hemoglobin was used to evaluate the postoperation result in PRCA. If PRCA can not be relieved, oral prednisone and cyclosporin A were given. Results: One patient with PRCA was cured, the second patient remained in remission by treatment with prednisone and CsA, and the third patient was in progress. Conclusion: The treatment by means of 'thymothymectomy-local radiotherapy-use of prednisone and CsA', is effective for thymoma associated with PRCA

  12. Recurrence of thymoma with pleural invasion in a patient with myasthenia gravis and pure red blood cell aplasia: a case report

    International Nuclear Information System (INIS)

    Rodriguez, Sonia Pilar; Zuluaga, Claudia Patricia; Uriza, Luis Felipe C; Sanchez M, Jully Mariana

    2008-01-01

    Thymoma are thymic tumors that arise from epithelial cells, they have different morphological characteristics. It is known for its association with autoimmune diseases such as myasthenia gravis, pure red cell aplasia, systemic lupus erythematosus, or hipogamaglobulinemia pemphigus foliaceus. The association thymoma-myasthenia gravis-pure red cell aplasia is a rare one; there will be a case report with the corresponding discussion and review of the literature

  13. Irreversible and irretrievable commitments of material resources

    International Nuclear Information System (INIS)

    1976-06-01

    In accordance with 10 CFR Part 51, ''Licensing and Regulatory Policy and Procedures for Environmental Protection,'' applicants are required to discuss any irreversible and irretrievable commitments of resources that would be involved in a proposed action, should it be implemented. The construction and operation of nuclear power stations involve commitments of such resources as water, fuel, and materials. The guide presented identifies a report on material resources that forms a basis acceptable to the NRC staff for required discussions of irreversible and irretrievable commitments of material resources involved in the construction of a 1000 MWe pressurized water reactor. The guide describes numerical estimates useful in all such discussions. It also provides methods of computation that may be referenced

  14. Optima and bounds for irreversible thermodynamic processes

    International Nuclear Information System (INIS)

    Hoffmann, K.H.

    1990-01-01

    In this paper bounds and optima for irreversible thermodynamic processes and their application in different fields are discussed. The tools of finite time thermodynamics are presented and especially optimal control theory is introduced. These methods are applied to heat engines, including models of the Diesel engine and a light-driven engine. Further bounds for irreversible processes are introduced, discussing work deficiency and its relation to thermodynamic length. Moreover the problem of dissipation in systems composed of several subsystems is studied. Finally, the methods of finite time thermodynamics are applied to thermodynamic processes described on a more microscopic level. The process used as an example is simulated annealing. It is shown how optimal control theory is applied to find the optimal cooling schedule for this important stochastic optimization method

  15. Irreversible Investment with Embodied Technological Progress

    OpenAIRE

    Bruno de Oliveira Cruz; Aude Pommeret

    2015-01-01

    In this paper, we propose to explain capital accumulation in a stochastic framework by taking into account the two main motives for investment. Specifically, firms invest to expand capacity and to replace old machines. The model considers irreversible investment under uncertainty and embodied technological progress. It is shown to be consistent with the following empirical observations: Investment is lumpy and infrequent at the firm level; firms can invest even if they have not reached full c...

  16. Mathematical models and equilibrium in irreversible microeconomics

    Directory of Open Access Journals (Sweden)

    Anatoly M. Tsirlin

    2010-07-01

    Full Text Available A set of equilibrium states in a system consisting of economic agents, economic reservoirs, and firms is considered. Methods of irreversible microeconomics are used. We show that direct sale/purchase leads to an equilibrium state which depends upon the coefficients of supply/demand functions. To reach the unique equilibrium state it is necessary to add either monetary exchange or an intermediate firm.

  17. Microscopic Irreversibility and the H Theorem

    Science.gov (United States)

    Magpantay, Jose A.

    2013-02-01

    Time-reversal had always been assumed to be a symmetry of physics at the fundamental level. In this paper we will explore the violations of time-reversal symmetry at the fundamental level and the consequence on thermodynamic systems. First, we will argue from current physics that the universe dynamics is not time-reversal invariant. Second, we will argue that any thermodynamic system cannot be isolated completely from the universe. We then discuss how these two make the dynamics of thermodynamics systems very weakly irreversible at the classical and quantum level. Since time-reversal is no longer a symmetry of realistic systems, the problem of how macroscopic irreversibility arises from microscopic reversibility becomes irrelevant because there is no longer microscopic reversibility. At the classical level of a thermodynamic system, we show that the H theorem of Boltzmann is still valid even without microscopic reversibility. We do this by deriving a modified H theorem, which still shows entropy monotonically increasing. At the quantum level, we explicitly show the effect of CP violation, small irreversible changes on the internal states of the nuclear and atomic energy levels of thermodynamic systems. Thus, we remove Loschmidt's objection to Boltzmann's ideas.

  18. Irreversible properties of YBCO coated conductors

    International Nuclear Information System (INIS)

    Vostner, A.

    2001-02-01

    Over the past few years substantial efforts were made to optimize the fabrication techniques of various high temperature superconductors for commercial applications. In addition to Bi-2223 tapes, Y-123 coated conductors have the potential for large-scale production and are considered as the second generation of superconducting 'wires' for high current applications. This work reports on magnetic and transport current investigations of Y-123 thick films deposited on either single crystalline substrates by liquid phase epitaxy (LPE) or on metallic substrates by pulsed laser deposition (PLD). At the beginning, a short introduction of the general idea of a coated conductor and of the different production techniques is presented, followed by a description of the different experimental set-ups and the evaluation methods. The main part starts with the results obtained from SQUID magnetometry and ac-susceptibility measurements including the transition temperatures T c , the field dependence of the magnetic critical current densities and the irreversibility lines. In addition, some issues concerning the granular structure and the inter- and intragranular current distribution of the superconducting films are discussed. The investigations by transport currents are focused on the behavior of the application relevant irreversible parameters. These are the angular and the field dependence of the critical transport current densities at 77 and 60 K, as well as the temperature dependence of the irreversibility fields up to 6 T. To gain more insight into the defect structure of the films, neutron irradiation studies were performed on some samples. The introduction of these artificial pinning centers causes large enhancements of the magnetic J c in LPE specimens for the field parallel to the c-axis (H//c) at higher temperatures and magnetic fields. The granular structure of the samples does not change up to the highest neutron fluences. However, the enhancements of the transport J c

  19. Incidental finding of unilateral isolated aplasia of serratus anterior muscle and winged scapula on chest radiograph: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon Sung; Park, Hyun Jin; Ko, Jeong Min [Dept. of Radiology, St. Vincent' s Hospital, College of Medicine, The Catholic University of Korea, Suwon (Korea, Republic of)

    2014-10-15

    The isolated aplasia of the serratus anterior muscle with winging of scapula is very rare, and only a few cases are reported. Here, we present a case of a 30-year-old Korean male who initially presented with a left flank pain. His physical exam did not show any significant finding in his right shoulder. However, his chest radiograph showed absence of right serratus anterior muscle and slightly elevated and medially rotated right scapula. Subsequent CT scan showed the right serratus anterior muscle aplasia and medial winging of the right scapula. This case is unique in two aspects. First, the combination of abnormalities is different from the typical congenital abnormalities involving shoulder girdle, such as Sprengel deformity or Poland syndrome. Secondly, this was incidentally diagnosed with chest radiograph, without clinical impression. Careful reading of chest radiograph can help the radiologists to detect such clinically silent abnormalities.

  20. Aplasia and agenesis of the frontal sinus in Turkish individuals: a retrospective study using dental volumetric tomography.

    Science.gov (United States)

    Çakur, Binali; Sumbullu, Muhammed A; Durna, Nurhan Bayındır

    2011-04-08

    Agenesis of the paranasal sinuses is an uncommon clinical condition that appears mainly in the frontal (12%) and maxillary (5-6%) sinuses; in some populations, it appears at a higher proportion. This study investigated the prevalence of agenesis of the frontal sinuses using dental volumetric tomography (DVT) in Turkish individuals. The frontal sinuses of 410 patients were examined by DVT scans in the coronal planes for evidence of the absence of the frontal sinuses. A bilateral and unilateral absence of the frontal sinuses was seen in 0.73% and 1.22% of cases, respectively. In one case, both agenesis and aplasia of the frontal sinus was seen (0.24%). The low percentage of frontal sinus agenesis must be considered during pre-surgical planning related to the sinuses. DVT may be used as a diagnostic tool for the examination of frontal sinus aplasia.

  1. 48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis

    Directory of Open Access Journals (Sweden)

    Baha Zantour

    2010-01-01

    Full Text Available A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family.

  2. 48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis

    Science.gov (United States)

    Zantour, Baha; Sfar, Mohamed Habib; Younes, Samia; Alaya, Wafa; Kamoun, Mahdi; Mkaouar, Emna; Jerbi, Saida

    2010-01-01

    A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family. PMID:20827436

  3. 48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis

    OpenAIRE

    Zantour, Baha; Sfar, Mohamed Habib; Younes, Samia; Alaya, Wafa; Kamoun, Mahdi; Mkaouar, Emna; Jerbi, Saida

    2010-01-01

    A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochon...

  4. Ex vivo expansion of haematopoietic cells in the treatment of accidental irradiation-induced aplasia. Feasibility Studies

    Energy Technology Data Exchange (ETDEWEB)

    Thierry, D.; Bertho, J.M.; Chapel, A.; Gourmelon, P. [Institut de Protection et de Surete Nucleaire, Fountenay-aux-Roses (France)

    2000-05-01

    The lessons learnt from the treatment of previous radiation accidents using either bone marrow transplantation or growth factor therapy suggest that it is of importance to investigate new therapeutic regiments. Ex vivo expansion of haematopoietic stem cells, precursors and differentiated cells is a new approach of growth factor therapy which may be of interest for the treatment of patients with irradiation-induced bone marrow aplasia. Ex vivo expanded maturing cells could be used to limit the early risks bound to aplasia (infections related to granulocytopaenia, bleedings associated with thrombocytopaenia), whereas expanded immature cells could hasten haematopoietic recovery. Indeed, it is possible to culture from the blood or bone marrow the cells able to proliferate and differentiate. A sufficient quantity of cells to cover the transfusion needs of a radiation victim through an aplasia episode can be produced, in presence of a specific growth factor combination. Qualitative studies shows that the expanded cells exhibit a close to normal functionality. Long-term culture techniques demonstrate the expansion of immature cells. We have set up a high dose total body irradiation non-human primate model in order to study the therapeutic potential of ex vivo expansion of autologous progenitors and differentiating cells. All the steps of the process (sampling, positive selection of the immature cells, ex vivo expansion, irradiation of the animals, reinjection of the cultured cells and study of the outcome) are established. In order to allow the long term follow up of the ex vivo expanded haematopoietic cells (homing to the bone marrow or localization to specific organs for example), a retroviral gene transfer technique for transduction of green fluorescence protein (GFP) gene toward the selected immature blood or bone marrow cells is under development in this model. Taken together these elements will allow establishing the feasibility of ex vivo expansion of

  5. Ex vivo expansion of haematopoietic cells in the treatment of accidental irradiation-induced aplasia. Feasibility Studies

    International Nuclear Information System (INIS)

    Thierry, D.; Bertho, J.M.; Chapel, A.; Gourmelon, P.

    2000-01-01

    The lessons learnt from the treatment of previous radiation accidents using either bone marrow transplantation or growth factor therapy suggest that it is of importance to investigate new therapeutic regiments. Ex vivo expansion of haematopoietic stem cells, precursors and differentiated cells is a new approach of growth factor therapy which may be of interest for the treatment of patients with irradiation-induced bone marrow aplasia. Ex vivo expanded maturing cells could be used to limit the early risks bound to aplasia (infections related to granulocytopaenia, bleedings associated with thrombocytopaenia), whereas expanded immature cells could hasten haematopoietic recovery. Indeed, it is possible to culture from the blood or bone marrow the cells able to proliferate and differentiate. A sufficient quantity of cells to cover the transfusion needs of a radiation victim through an aplasia episode can be produced, in presence of a specific growth factor combination. Qualitative studies shows that the expanded cells exhibit a close to normal functionality. Long-term culture techniques demonstrate the expansion of immature cells. We have set up a high dose total body irradiation non-human primate model in order to study the therapeutic potential of ex vivo expansion of autologous progenitors and differentiating cells. All the steps of the process (sampling, positive selection of the immature cells, ex vivo expansion, irradiation of the animals, reinjection of the cultured cells and study of the outcome) are established. In order to allow the long term follow up of the ex vivo expanded haematopoietic cells (homing to the bone marrow or localization to specific organs for example), a retroviral gene transfer technique for transduction of green fluorescence protein (GFP) gene toward the selected immature blood or bone marrow cells is under development in this model. Taken together these elements will allow establishing the feasibility of ex vivo expansion of

  6. Plasma free reversible and irreversible microfluidic bonding.

    Science.gov (United States)

    Chu, M; Nguyen, T T; Lee, E K; Morival, J L; Khine, M

    2017-01-17

    We demonstrate a facile, plasma free process to fabricate both reversibly and irreversibly sealed microfluidic chips using a PDMS-based adhesive polymer mixture. This is a versatile method that is compatible with current PDMS microfluidics processes. It allows for easier fabrication of multilayer microfluidic devices and is compatible with micropatterning of proteins for cell culturing. When combined with our Shrinky-Dink microfluidic prototyping, complete microfluidic device fabrication can be performed without the need for any capital equipment, making microfluidics accessible to the classroom.

  7. Statistical mechanics out of equilibrium the irreversibility

    International Nuclear Information System (INIS)

    Alvarez Estrada, R. F.

    2001-01-01

    A Round Table about the issue of Irreversibility and related matters has taken place during the last (20th) Statistical Mechanics Conference, held in Paris (July 1998). This article tries to provide a view (necessarily limited, and hence, uncompleted) of some approaches to the subject: the one based upon deterministic chaos (which is currently giving rise to a very active research) and the classical interpretation due to Boltzmann. An attempt has been made to write this article in a self-contained way, and to avoid a technical presentation wherever possible. (Author) 29 refs

  8. Common crus aplasia: diagnosis by 3D volume rendering imaging using 3DFT-CISS sequence

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.J. E-mail: hakjink@pusan.ac.kr; Song, J.W.; Chon, K.-M.; Goh, E.-K

    2004-09-01

    AIM: The purpose of this study was to evaluate the findings of three-dimensional (3D) volume rendering (VR) imaging in common crus aplasia (CCA) of the inner ear. MATERIALS AND METHODS: Using 3D VR imaging of temporal bone constructive interference in steady state (CISS) magnetic resonance (MR) images, we retrospectively reviewed seven inner ears of six children who were candidates for cochlear implants and who had been diagnosed with CCA. As controls, we used the same method to examine 402 inner ears of 201 patients who had no clinical symptoms or signs of sensorineural hearing loss. Temporal bone MR imaging (MRI) was performed with a 1.5 T MR machine using a CISS sequence, and VR of the inner ear was performed on a work station. Morphological image analysis was performed on rotation views of 3D VR images. RESULTS: In all seven cases, CCA was diagnosed by the absence of the common crus. The remaining superior semicircular canal (SCC) was normal in five and hypoplastic in two inner ears, while the posterior SCC was normal in all seven. One patient showed bilateral symmetrical CCA. Complicated combined anomalies were seen in the cochlea, vestibule and lateral SCC. CONCLUSION: 3D VR imaging findings with MR CISS sequence can directly diagnose CCA. This technique may be useful in delineating detailed anomalies of SCCs.

  9. A case of pure red cell aplasia during nivolumab therapy for cardiac metastatic melanoma.

    Science.gov (United States)

    Yuki, Akihiko; Takenouchi, Tatsuya; Takatsuka, Sumiko; Ishiguro, Takuro

    2017-12-01

    Nivolumab is an antibody against programmed cell death 1 and functions as an immune checkpoint inhibitor for various malignancies, including unresectable melanomas. Nivolumab causes several immune-related adverse events, which typically include skin rash, pneumonitis, thyroid dysfunction, hepatitis, and colitis; in rare cases, anemia may be present. There are several reports of autoimmune hemolytic anemia that has developed in response to nivolumab; however, there are few reports of pure red cell aplasia (PRCA). We describe a patient who developed PRCA during nivolumab administration. A 70-year-old Japanese woman received nivolumab for cardiac metastasis from malignant melanoma from an unknown site. Twenty-one months after nivolumab administration (31 courses), treatment was discontinued because she developed severe anemia. Blood test results indicated normocytic, normochromic anemia, and reticulocytopenia, but all other components were normal. Bone marrow aspiration showed increased megakaryocytes and decreased erythroblasts; these findings were consistent with PRCA. Anemia improved without recurrence after treatment with corticosteroids and blood transfusions. The steroid dosage was reduced gradually, and to date, the patient has not experienced recurrence of anemia. The tumor decreased in size and the patient has shown a continued response to treatment with decrease in disease for 3 years. Although it is unclear how nivolumab causes PRCA, hematological toxicities have been reported in patients treated with immunotherapy drugs. PRCA might be an unrecognized immune-mediated adverse event that did not manifest during the clinical trial phase.

  10. Simultaneous occurrence of autoimmune hemolytic anemia and pure red cell aplasia.

    Science.gov (United States)

    Adachi, Masaaki

    2016-01-01

    Simultaneous onset of autoimmune hemolytic anemia (AIHA) and pure red cell aplasia (PRCA) is rare and any possible association between these two disorders remains obscure. A 46-year-old previously healthy woman was diagnosed as having AIHA based on severe anemia, positive direct and indirect Coomb's tests, decreased serum haptoglobin, elevated serum LDH, and indirect bilirubin-dominant hyperbilirubinemia. Oral steroid administration (1 mg/kg) and subsequent half-pulse steroid therapy ameliorated the AIHA, but the anemia was unexpectedly prolonged with the low peripheral blood reticulocyte count further decreasing to 0.11%. Bone marrow aspiration revealed a marked decrease in erythroblasts with an M/E ratio of 69.5. Anti-parvovirus B19 IgM antibody and serum B19 viral DNA (10 9 copy/ml) were detected but no other distinct abnormalities which might have caused acquired PRCA were detected. Therefore, she was considered likely to have idiopathic AIHA and acquired PRCA simultaneously. AIHA-mediated erythroblastosis probably raised the parvovirus B19 DNA level to an extraordinary degree and thereby led to severe aplastic crisis, subsequently causing prolonged anemia. Parvovirus B19 infection should be considered in AIHA patients showing unexpectedly low reticulocyte counts.

  11. A patient with van Maldergem syndrome with endocrine abnormalities, hypogonadotropic hypogonadism, and breast aplasia/hypoplasia.

    Science.gov (United States)

    Sotos, Juan; Miller, Katherine; Corsmeier, Donald; Tokar, Naomi; Kelly, Benjamin; Nadella, Vijay; Zhong, Huachun; Wetzel, Amy; Adler, Brent; Yu, Chack-Yung; White, Peter

    2017-01-01

    We report a female patient with endocrine abnormalities, hypogonadotropic hypogonadism and amazia (breasts aplasia/hypoplasia but normal nipples and areolas) in a rare syndrome: Van Maldergem syndrome (VMS). Our patient was first evaluated at age 4 for intellectual disability, craniofacial features, and auditory malformations. At age 15, she presented with no breast development and other findings consistent with hypogonadotropic hypogonadism. At age 37, she underwent whole exome sequencing (WES) to identify pathogenic variants. WES revealed compound heterozygous variants in DCHS1 (rs145099391:G > A, p.P197L & rs753548138:G > A, p .T2334 M) [RefSeq NM_003737.3], diagnostic of Van Maldergem syndrome (VMS-1). VMS is a rare autosomal disorder reported in only 13 patients, characterized by intellectual disability, typical craniofacial features, auditory malformations, hearing loss, skeletal and limb malformations, brain abnormalities with periventricular neuronal heterotopia and other variable anomalies. Our patient had similar phenotypic abnormalities. She also had hypogonadotropic hypogonadism and amazia. Based on the clinical findings reported, two previously published patients with VMS may also have been affected by hypogonadotropic hypogonadism, but endocrine abnormalities were not evaluated or mentioned. This case highlights an individual with VMS, characterized by compound heterozygous variants in DCHS1 . Our observations may provide additional information on the phenotypic spectrum of VMS, including hypogonadotropic hypogonadism and amazia. However, the molecular genetic basis for endocrine anomalies observed in some VMS patients, including ours, remains unexplained.

  12. Common crus aplasia: diagnosis by 3D volume rendering imaging using 3DFT-CISS sequence

    International Nuclear Information System (INIS)

    Kim, H.J.; Song, J.W.; Chon, K.-M.; Goh, E.-K.

    2004-01-01

    AIM: The purpose of this study was to evaluate the findings of three-dimensional (3D) volume rendering (VR) imaging in common crus aplasia (CCA) of the inner ear. MATERIALS AND METHODS: Using 3D VR imaging of temporal bone constructive interference in steady state (CISS) magnetic resonance (MR) images, we retrospectively reviewed seven inner ears of six children who were candidates for cochlear implants and who had been diagnosed with CCA. As controls, we used the same method to examine 402 inner ears of 201 patients who had no clinical symptoms or signs of sensorineural hearing loss. Temporal bone MR imaging (MRI) was performed with a 1.5 T MR machine using a CISS sequence, and VR of the inner ear was performed on a work station. Morphological image analysis was performed on rotation views of 3D VR images. RESULTS: In all seven cases, CCA was diagnosed by the absence of the common crus. The remaining superior semicircular canal (SCC) was normal in five and hypoplastic in two inner ears, while the posterior SCC was normal in all seven. One patient showed bilateral symmetrical CCA. Complicated combined anomalies were seen in the cochlea, vestibule and lateral SCC. CONCLUSION: 3D VR imaging findings with MR CISS sequence can directly diagnose CCA. This technique may be useful in delineating detailed anomalies of SCCs

  13. Localized orthodontic space closure for unilateral aplasia of lower second premolars.

    Science.gov (United States)

    Zimmer, Bernd; Schelper, Ina; Seifi-Shirvandeh, Nasrin

    2007-04-01

    The present study aimed to determine whether routine orthodontic space closure can be successfully achieved in patients with unilateral aplasia of the lower second premolars without extracting contralateral or opposing teeth. The dental records and lateral cephalograms of 17 consecutively treated subjects (11 females, 6 males) aged between 14.8 and 19.3 years at the end of active treatment (mean 16.1 years) were analysed. The spaces were closed by 'push-and-pull' mechanics (PPM). Pre- and post-treatment data were compared using a Student's t-test. At the end of active treatment, all parameters (ANB, SNA, SNB, ML/NL, U1-NA, L1-NB, overbite and overjet, upper and lower midline, upper and lower space balance) presented mean values close to accepted norms with satisfactory standard deviations (SDs). Five indicators of success changed significantly: (1) Space closure in the aplastic region was achieved. (2) On the aplastic side, a mean mesial molar relationship of 1.12 (SD 0.18) cusp width (cw) was achieved. The mean alteration from pre- to post-treatment was 1.53 cw (SD 0.29, P space and balanced space ratios.

  14. Anistropically varying conductivity in irreversible electroporation simulations.

    Science.gov (United States)

    Labarbera, Nicholas; Drapaca, Corina

    2017-11-01

    One recent area of cancer research is irreversible electroporation (IRE). Irreversible electroporation is a minimally invasive procedure where needle electrodes are inserted into the body to ablate tumor cells with electricity. The aim of this paper is to propose a mathematical model that incorporates a tissue's conductivity increasing more in the direction of the electrical field as this has been shown to occur in experiments. It was necessary to mathematically derive a valid form of the conductivity tensor such that it is dependent on the electrical field direction and can be easily implemented into numerical software. The derivation of a conductivity tensor that can take arbitrary functions for the conductivity in the directions tangent and normal to the electrical field is the main contribution of this paper. Numerical simulations were performed for isotropic-varying and anisotropic-varying conductivities to evaluate the importance of including the electrical field's direction in the formulation for conductivity. By starting from previously published experimental results, this paper derived a general formulation for an anistropic-varying tensor for implementation into irreversible electroporation modeling software. The anistropic-varying tensor formulation allows the conductivity to take into consideration both electrical field direction and magnitude, as opposed to previous published works that only took into account electrical field magnitude. The anisotropic formulation predicts roughly a five percent decrease in ablation size for the monopolar simulation and approximately a ten percent decrease in ablation size for the bipolar simulations. This is a positive result as previously reported results found the isotropic formulation to overpredict ablation size for both monopolar and bipolar simulations. Furthermore, it was also reported that the isotropic formulation overpredicts the ablation size more for the bipolar case than the monopolar case. Thus, our

  15. Entropy, Extropy and the Physical Driver of Irreversibility

    Directory of Open Access Journals (Sweden)

    Attila Grandpierre

    2012-06-01

    Full Text Available We point out that the fundamental irreversibility of Nature requires the introduction of a suitable measure for the distance from equilibrium. We show that entropy, which is widely held to be such a measure, suffers from the problem that it does not have a physical meaning, since it is introduced on the basis of mathematical arguments. As a consequence, the basic physics beyond irreversibility has remained obscure. We present here a simple but transparent physical approach for solving the problem of irreversibility. This approach shows that extropy, the fundamental thermodynamic variable introduced by Katalin Martinás, is the suitable measure for the distance from equilibrium, since it corresponds to the actual driver of irreversible processes. Since extropy explicitly contains in its definition all the general thermodynamic forces that drive irreversible processes, extropy is the suitable physical measure of irreversibility.

  16. Competing irreversible cooperative reactions on polymer chains

    International Nuclear Information System (INIS)

    Evans, J.W.; Hoffman, D.K.; Burgess, D.R.

    1984-01-01

    We analyze model processes involving competition between several irreversible reactions at the sites of a 1D, infinite, uniform polymer chain. These reactions can be cooperative, i.e., the corresponding rates depend on the state of the surrounding sites. An infinite hierarchy of rate equations is readily derived for the probabilities of various subconfigurations. By exploiting a shielding property of suitable blocks of unreacted sites, we show how exact hierarchy truncation and solution is sometimes possible. The behavior of solutions is illustrated in several cases by plotting families of ''reaction trajectories'' for varying ratios of reactant concentrations. As a specific application, we consider competition between coordination of ZnCl 2 to pairs of oxygen atoms and to single oxygen atoms in poly(propylene oxide). The observed glass transition temperature behavior is eludicated

  17. Exergetic sustainability evaluation of irreversible Carnot refrigerator

    Science.gov (United States)

    Açıkkalp, Emin

    2015-10-01

    Purpose of this paper is to assess irreversible refrigeration cycle by using exergetic sustainability index. In literature, there is no application of exergetic sustainability index for the refrigerators and, indeed, this index has not been derived for refrigerators. In this study, exergetic sustainability indicator is presented for the refrigeration cycle and its relationships with other thermodynamics parameters including COP, exergy efficiency, cooling load, exergy destruction, ecological function and work input are investigated. Calculations are conducted for endoreversible and reversible cycles and then results obtained from the ecological function are compared. It is found that exergy efficiency, exergetic sustainable index reduce 47.595% and 59.689% and rising at the COP is 99.888% is obtained for endoreversible cycle. Similarly, exergy efficiency and exergetic sustainability index reduce 90.163% and 93.711% and rising of the COP is equal to 99.362%.

  18. Diffusion of irreversible energy technologies under uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Cacallo, J.D.; Sutherland, R.J.

    1993-09-01

    This paper presents a model of technology diffusion is consistent with characteristics of participants in most energy markets. Whereas the models used most widely for empirical research are based on the assumption that the extended delays in adoption of cost-saving innovations are the result of either lack of knowledge about the new processes or heterogeneity across potential adopters, the model presented in this paper is based on the strategic behavior by firms. The strategic interdependence of the firms` decisions is rooted in spillover effects associated with an inability to exclude others from the learning-by-doing acquired when a firm implements a new technology. The model makes extensive use of recent developments in investment theory as it relates irreversible investments under uncertainty.

  19. Chemical kinetics, stochastic processes, and irreversible thermodynamics

    CERN Document Server

    Santillán, Moisés

    2014-01-01

    This book brings theories in nonlinear dynamics, stochastic processes, irreversible thermodynamics, physical chemistry, and biochemistry together in an introductory but formal and comprehensive manner.  Coupled with examples, the theories are developed stepwise, starting with the simplest concepts and building upon them into a more general framework.  Furthermore, each new mathematical derivation is immediately applied to one or more biological systems.  The last chapters focus on applying mathematical and physical techniques to study systems such as: gene regulatory networks and ion channels. The target audience of this book are mainly final year undergraduate and graduate students with a solid mathematical background (physicists, mathematicians, and engineers), as well as with basic notions of biochemistry and cellular biology.  This book can also be useful to students with a biological background who are interested in mathematical modeling, and have a working knowledge of calculus, differential equatio...

  20. Principle of maximum entropy and irreversible processes

    International Nuclear Information System (INIS)

    Grandy, W.T. Jr.

    1980-01-01

    More than twenty years have passed since E.T. Jaynes pioneered the information-theoretic approach to the foundations of statistical mechanics. In the intervening period numerous applications have been worked out and new insights developed into traditional problems. Although the natural extension of these ideas to nonequilibrium statistical mechanics and irreversible processes has also been formulated, and both theory and applications have been considerably developed, much of this work has not appeared in the open literature. Yet the basic ideas and consequent theory seem to have an extraordinary unifying and illumination effect on the foundations of the many-body problem, as well as providing a transparent conceptual basis from which to view various groups of problems not previously formulated in a particularly sharp way. The aim of this review is to summarize these developements in the context of the principle of maximum entropy. (orig.)

  1. Aplasia cutis congenita of the scalp- what are the steps to be followed? Case report and review of the literature*

    Science.gov (United States)

    Brzezinski, Piotr; Pinteala, Tudor; Chiriac, Anca E; Foia, Liliana; Chiriac, Anca

    2015-01-01

    Aplasia cutis congenita is a rare malformation characterized by localized congenital absence of the skin. It rarely occurs on the trunk and limbs, and can occur in isolation or as part of a heterogeneous group of syndromes. We report a case of a 4-day-old boy with a 5.6-cm- diameter tumor, with a central crust, non-indurate and no inflammatory rim; localized on the scalp and a small, atrophic hairless scar appeared 6 months later (approximately 5cm in length) at the site of the previous tumor. PMID:25672305

  2. Associação entre aplasia segmentar de veia safena magna e varizes em membros inferiores avaliada pelo ecocolor Doppler

    Directory of Open Access Journals (Sweden)

    Amélia Cristina Seidel

    2015-09-01

    Full Text Available ResumoContextoHá diferenças individuais no diâmetro da veia safena magna (VSM em membros normais e doentes; sendo possível a identificação dessas alterações pelo ecocolor Doppler.ObjetivoAvaliar a associação da aplasia segmentar da VSM com a presença de varizes e/ou insuficiência da mesma em membros inferiores, usando o ecocolor Doppler em pacientes com clínica de doença venosa crônica (DVC.Métodos1.408 pacientes com queixas compatíveis de DVC de membros inferiores, sendo 1.286 do sexo feminino, com idade entre 17 e 85 anos, examinados com ecocolor Doppler. Foram incluídos aqueles com classificação CEAP clínica C0 a C4. Pela avaliação clínica, a amostra foi distribuída em grupo A, pacientes com varizes, e grupo B, aqueles sem varizes. O ecocolor Doppler determinou se havia aplasia da VSM pela análise do seu trajeto no compartimento safeno e presença de veias varicosas nos diferentes sítios. Para estatística, foram considerados os testes Qui-quadrado ou Exato de Fisher e uma análise de resíduos em tabelas, com nível de significância de 5%.ResultadosNo grupo A houve 479 (83,9% de VSM insuficientes, 169 (38,2% com aplasia e 71 (80,7% com insuficiência e aplasia associadas. No grupo B, houve 92 (16,1% de VSM insuficientes, 273 (61,8% com aplasia e 17 (19,3% com insuficiência e aplasia associadas.ConclusãoA aplasia segmentar da VSM ocorre mais em membros inferiores que não apresentam varizes e/ou insuficiência da mesma, mas considerando-se a presença da associação de aplasia e insuficiência, houve maior incidência no grupo de membros que apresentavam varizes.

  3. Hematopoiesis stimulation test by interleukin 1α gene transfer in the Cynomolgus macaque: application to secondary medullary aplasia from an accidental irradiation

    International Nuclear Information System (INIS)

    De Revel, Th.

    2002-12-01

    After a description of the context of medullary aplasia (haematological radiobiology, radiation acute syndrome, therapeutic care), and an overview of knowledge about the interleukin-1 and medullary stroma cells, this research thesis aims at investigating therapeutic alternatives for radio-accidental aplasia. More precisely, it aims at defining means to get cytokines which are efficient for haematopoiesis. Interleukin-1 is chosen for its properties and tests are performed on a macaque with two approaches for gene transfer: an ex vivo transfer by retroviral vector enabling an integration in the target cell genome, and an in situ transfer by adeno-viral vector directly applied in the animal osseous medulla

  4. Bacterial, fungal and yeast contamination in six brands of irreversible hydrocolloid impression materials Contaminação por bactérias, fungos e leveduras em seis marcas comerciais de materiais de moldagem à base de hidrocolóide irreversível

    Directory of Open Access Journals (Sweden)

    Luciana Assirati Casemiro

    2007-06-01

    Full Text Available This study assessed the level of contamination of six commercially available irreversible hydrocolloids (two containing chlorhexidine and identified the contamination present in the materials. Petri dishes containing selective and enriched culture media were inoculated with alginate powder (0.06 g, in triplicate. After incubation (37°C/7 days, the colony-forming units (CFU were counted and Gram stained. Biochemical identification of the different morphotypes was also performed. The contamination levels for the materials were: Jeltrate - 389 CFU/g; Jeltrate Plus - 516 CFU/g; Jeltrate Chromatic - 135 CFU/g; Hydrogum - 1,455 CFU/g; Kromopan - 840 CFU/g; and Greengel - 59 CFU/g. Gram staining revealed the presence of Gram-positive bacillus and Gram-positive cocci. The bacteria Staphylococcus epidermidis, Bacillus subtilis, Bacillus sp., Bacillus coagulans, Bacillus licheniformis, Bacillus cereus, Micrococcus luteus, and Nocardia sp.; the filamentous fungi Aspergillus niger, Aspergillus flavus, Rhizopus sp., Neurospora sp.; and the yeast Candida sp. were isolated. The contamination detected in the impression materials points out the need for adopting measures to improve the microbiological quality of these materials. The use of contaminated materials in the oral cavity goes against the basic principles for controlling cross-contamination and may represent a risk for debilitated or immunocompromised patients.Este estudo avaliou o nível de contaminação de seis marcas comerciais de alginato (duas contendo clorexidina e identificou a contaminação presente nesses materiais. Alíquotas de alginato (0,06 g foram semeadas em meios de cultura seletivos e enriquecidos, em triplicata. Após incubação (37°C/7 dias, as unidades formadoras de colônia (UFC foram contadas e foram realizadas as identificações morfotintorial (Gram e bioquímica. Os níveis de contaminação dos materiais foram: Jeltrate - 389 UFC/g; Jeltrate Plus - 516 UFC/g; Jeltrate

  5. The Anesthetic Efficacy of the Intraosseous Injection in Irreversible Pulpitis.

    Science.gov (United States)

    1995-01-01

    The purpose of this study was to evaluate the anesthetic efficacy of an intraosseous injection in teeth diagnosed with irreversible pulpitis . Fifty...one healthy human subjects with symptomatic maxillary or mandibular posterior teeth diagnosed with irreversible pulpitis were used in this study. The

  6. Formation of Irreversible H-bonds in Cellulose Materials

    Science.gov (United States)

    Umesh P. Agarwal; Sally A. Ralph; Rick S. Reiner; Nicole M. Stark

    2015-01-01

    Understanding of formation of irreversible Hbonds in cellulose is important in a number of fields. For example, fields as diverse as pulp and paper and enzymatic saccharification of cellulose are affected. In the present investigation, the phenomenon of formation of irreversible H-bonds is studied in a variety of celluloses and under two different drying conditions....

  7. Combustion irreversibilities: Numerical simulation and analysis

    Science.gov (United States)

    Silva, Valter; Rouboa, Abel

    2012-08-01

    An exergy analysis was performed considering the combustion of methane and agro-industrial residues produced in Portugal (forest residues and vines pruning). Regarding that the irreversibilities of a thermodynamic process are path dependent, the combustion process was considering as resulting from different hypothetical paths each one characterized by four main sub-processes: reactant mixing, fuel oxidation, internal thermal energy exchange (heat transfer), and product mixing. The exergetic efficiency was computed using a zero dimensional model developed by using a Visual Basic home code. It was concluded that the exergy losses were mainly due to the internal thermal energy exchange sub-process. The exergy losses from this sub-process are higher when the reactants are preheated up to the ignition temperature without previous fuel oxidation. On the other hand, the global exergy destruction can be minored increasing the pressure, the reactants temperature and the oxygen content on the oxidant stream. This methodology allows the identification of the phenomena and processes that have larger exergy losses, the understanding of why these losses occur and how the exergy changes with the parameters associated to each system which is crucial to implement the syngas combustion from biomass products as a competitive technology.

  8. Structure of Irreversibly Adsorbed Star Polymers

    Science.gov (United States)

    Akgun, Bulent; Aykan, Meryem Seyma; Canavar, Seda; Satija, Sushil K.; Uhrig, David; Hong, Kunlun

    Formation of irreversibly adsorbed polymer chains on solid substrates have a huge impact on the wetting, glass transition, aging and polymer chain mobility in thin films. In recent years there has been many reports on the formation, kinetics and dynamics of these layers formed by linear homopolymers. Recent studies showed that by varying the number of polymer arms and arm molecular weight one can tune the glass transition temperature of thin polymer films. Using polymer architecture as a tool, the behavior of thin films can be tuned between the behavior of linear chains and soft colloids. We have studied the effect of polymer chain architecture on the structure of dead layer using X-ray reflectivity (XR) and atomic force microscopy. Layer thicknesses and densities of flattened and loosely adsorbed chains has been measured for linear, 4-arm, and 8-arm star polymers with identical total molecular weight as a function of substrate surface energy, annealing temperature and annealing time. Star polymers have been synthesized using anionic polymerization. XR measurements showed that 8-arm star PS molecules form the densest and the thickest dead layers among these three molecules.

  9. Irreversible energy flow in forced Vlasov dynamics

    KAUST Repository

    Plunk, Gabriel G.

    2014-10-01

    © EDP Sciences, Società Italiana di Fisica, Springer-Verlag. The recent paper of Plunk [G.G. Plunk, Phys. Plasmas 20, 032304 (2013)] considered the forced linear Vlasov equation as a model for the quasi-steady state of a single stable plasma wavenumber interacting with a bath of turbulent fluctuations. This approach gives some insight into possible energy flows without solving for nonlinear dynamics. The central result of the present work is that the forced linear Vlasov equation exhibits asymptotically zero (irreversible) dissipation to all orders under a detuning of the forcing frequency and the characteristic frequency associated with particle streaming. We first prove this by direct calculation, tracking energy flow in terms of certain exact conservation laws of the linear (collisionless) Vlasov equation. Then we analyze the steady-state solutions in detail using a weakly collisional Hermite-moment formulation, and compare with numerical solution. This leads to a detailed description of the Hermite energy spectrum, and a proof of no dissipation at all orders, complementing the collisionless Vlasov result.

  10. Irreversible work in a thermal medium with colored noise

    International Nuclear Information System (INIS)

    Ohkuma, Takahiro

    2009-01-01

    Irreversible work and its fluctuations in a classical system governed by non-Markovian stochastic dynamics are investigated. The production of irreversible work depends not only on the protocol of an operation but also on the details of the non-Markovian memory. We consider a generalized Langevin equation with a memory kernel and derive an expression for the irreversible work in the case of slow operations by carrying out an expansion of this memory kernel in the parameter representing the length of the memory. We apply our formulation to a harmonically trapped system and demonstrate the efficiency of a cycle by evaluating the irreversible work. It is found that a decrease in the irreversible work due to the memory effect can occur for an operation through which the trap is squeezed. The results for this harmonic system are verified exactly in the case that the memory kernel has exponential decay

  11. Irreversible work in a thermal medium with colored noise

    Science.gov (United States)

    Ohkuma, Takahiro

    2009-10-01

    Irreversible work and its fluctuations in a classical system governed by non-Markovian stochastic dynamics are investigated. The production of irreversible work depends not only on the protocol of an operation but also on the details of the non-Markovian memory. We consider a generalized Langevin equation with a memory kernel and derive an expression for the irreversible work in the case of slow operations by carrying out an expansion of this memory kernel in the parameter representing the length of the memory. We apply our formulation to a harmonically trapped system and demonstrate the efficiency of a cycle by evaluating the irreversible work. It is found that a decrease in the irreversible work due to the memory effect can occur for an operation through which the trap is squeezed. The results for this harmonic system are verified exactly in the case that the memory kernel has exponential decay.

  12. Conservative Healing of an 11 × 9-cm Aplasia Cutis Congenita of the Scalp with Bone Defect

    Science.gov (United States)

    Fröjd, Victoria; Maltese, Giovanni; Kölby, Lars; Tarnow, Peter

    2014-01-01

    Objectives Aplasia cutis congenita is a rare congenital condition, and it is difficult to find scientific support for optimal treatment strategies. In addition, these may vary due to defect size, tissue layers involved, contemporary malformations, and the physiologic status of the affected child. Clinical Presentation This case report describes complete skin coverage in 20 weeks and uneventful healing of a large 11 × 9-cm defect of the vertex, involving both skin and skull bone, using conservative treatment. To prevent infection and promote healing, the defect was kept moist and covered at all times, and it was treated with surgical debridement when necessary. For infection control, ionized silver-coated dressings were used in addition to prophylactic antibiotics over the first 3.5 weeks. Follow-up was 2 years. Conclusion Surgical treatment is usually preferred for larger aplasia cutis congenita defects, but it is accompanied with potential risks and will exacerbate secondary reconstruction of alopecia or skull bone defects. This case shows that even very complex defects may be treated conservatively. PMID:25485218

  13. Irreversible electroporation in a Swine lung model.

    Science.gov (United States)

    Dupuy, Damian E; Aswad, Bassam; Ng, Thomas

    2011-04-01

    This study was designed to evaluate the safety and tissue effects of IRE in a swine lung model. This study was approved by the institutional animal care committee. Nine anesthetized domestic swine underwent 15 percutaneous irreversible electroporation (IRE) lesion creations (6 with bipolar and 3 with 3-4 monopolar electrodes) under fluoroscopic guidance and with pancuronium neuromuscular blockade and EKG gating. IRE electrodes were placed into the central and middle third of the right mid and lower lobes in all animals. Postprocedure PA and lateral chest radiographs were obtained to evaluate for pneumothorax. Three animals were sacrificed at 2 weeks and six at 4 weeks. Animals underwent high-resolution CT scanning and PA and lateral radiographs 1 h before sacrifice. The treated lungs were removed en bloc, perfused with formalin, and sectioned. Gross pathologic and microscopic changes after standard hematoxylin and eosin staining were analyzed within the areas of IRE lesion creation. No significant adverse events were identified. CT showed focal areas of spiculated high density ranging in greatest diameter from 1.1-2.2 cm. On gross inspection of the sectioned lung, focal areas of tan discoloration and increased density were palpated in the areas of IRE. Histological analysis revealed focal areas of diffuse alveolar damage with fibrosis and inflammatory infiltration that respected the boundaries of the interlobular septae. No pathological difference could be discerned between the 2- and 4-week time points. The bronchioles and blood vessels within the areas of IRE were intact and did not show signs of tissue injury. IRE creates focal areas of diffuse alveolar damage without creating damage to the bronchioles or blood vessels. Short-term safety in a swine model appears to be satisfactory.

  14. SÍNDROME HEMOFAGOCÍTICO SECUNDARIO A INFECCIÓN POR ERYTHROVIRUS B19 Y EMBARAZO

    OpenAIRE

    Guzmán González,Eduardo; Rico 0lvera,Hugo; Vidal González,Víctor Manuel; Figueroa Damián,Ricardo

    2008-01-01

    Antecedentes: El síndrome hemofagocítico es un desorden caracterizado por una proliferación benigna de los histiocitos y la fagocitosis de las células hematopoiéticas normales. Puede ocurrir por diversos estados de compromiso inmunológico o secundario a una gran variedad de infecciones. El comportamiento clínico puede presentarse desde una rápida recuperación hasta la muerte. Caso: Se descubrió una aplasia hematopoiética en una mujer de 27 años con 22 semanas de gestación sin factores de ries...

  15. Investment Irreversibility and Precautionary Savings in General Equilibrium

    DEFF Research Database (Denmark)

    Ejarque, João

    Partial equilibrium models suggest that when uncertainty increases, agents increase savings and at the same time reduce investment in irreversible goods. This paper characterizes this problem in general equilibrium with technology shocks, additive output shocks and shocks to the marginal efficiency...... of investment. Uncertainty is associated with the variance of these random variables, and irreversibility is introduced by a non negativity constraint on investment. I find that irreversibility and changes in uncertainty can be responsible for sizeable movements in aggregate consumption and investment only...... if the shocks affect the marginal efficiency of investment. For all types of shocks, when concavity of the utility function is moderate or high, the irreversibility constraint never binds and the increase in variance has a negligible impact. Persistence in the shock process induces precautionary savings rather...

  16. Kinetic theory of nonequilibrium ensembles, irreversible thermodynamics, and generalized hydrodynamics

    CERN Document Server

    Eu, Byung Chan

    2016-01-01

    This book presents the fundamentals of irreversible thermodynamics for nonlinear transport processes in gases and liquids, as well as for generalized hydrodynamics extending the classical hydrodynamics of Navier, Stokes, Fourier, and Fick. Together with its companion volume on relativistic theories, it provides a comprehensive picture of the kinetic theory formulated from the viewpoint of nonequilibrium ensembles in both nonrelativistic and, in Vol. 2, relativistic contexts. Theories of macroscopic irreversible processes must strictly conform to the thermodynamic laws at every step and in all approximations that enter their derivation from the mechanical principles. Upholding this as the inviolable tenet, the author develops theories of irreversible transport processes in fluids (gases or liquids) on the basis of irreversible kinetic equations satisfying the H theorem. They apply regardless of whether the processes are near to or far removed from equilibrium, or whether they are linear or nonlinear with respe...

  17. Thermodynamic Analysis of an Irreversible Maisotsenko Reciprocating Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Fuli Zhu

    2018-03-01

    Full Text Available An irreversible Maisotsenko reciprocating Brayton cycle (MRBC model is established using the finite time thermodynamic (FTT theory and taking the heat transfer loss (HTL, piston friction loss (PFL, and internal irreversible losses (IILs into consideration in this paper. A calculation flowchart of the power output (P and efficiency (η of the cycle is provided, and the effects of the mass flow rate (MFR of the injection of water to the cycle and some other design parameters on the performance of cycle are analyzed by detailed numerical examples. Furthermore, the superiority of irreversible MRBC is verified as the cycle and is compared with the traditional irreversible reciprocating Brayton cycle (RBC. The results can provide certain theoretical guiding significance for the optimal design of practical Maisotsenko reciprocating gas turbine plants.

  18. Maximum power and thermal efficiency of an irreversible power cycle

    Science.gov (United States)

    Ait-Ali, Mohand A.

    1995-10-01

    A simple Carnot-like irreversible power cycle is modeled with two isothermal and two adiabatic, irreversible processes. The generic source of internal irreversibility, deduced from the Clausius inequality, produces entropy at a rate proportional to the external heat conductance and the engine temperature ratio. This cycle is optimized for maximum power and maximum efficiency, and its performances compared to those of the endoreversible cycle, based on typical heat source and heat sink temperatures. Both cycles produce maximum power at the same engine temperature ratio, but the irreversible cycle prediction of maximum efficiency and heat conductance allocation between steam boiler and condenser, appear to be not only more realistic, but also more relevant to actual design considerations of power plants.

  19. Irreversibility and dissipation in finite-state automata

    International Nuclear Information System (INIS)

    Ganesh, Natesh; Anderson, Neal G.

    2013-01-01

    Irreversibility and dissipation in finite-state automata (FSA) are considered from a physical-information-theoretic perspective. A quantitative measure for the computational irreversibility of finite automata is introduced, and a fundamental lower bound on the average energy dissipated per state transition is obtained and expressed in terms of FSA irreversibility. The irreversibility measure and energy bound are germane to any realization of a deterministic automaton that faithfully registers abstract FSA states in distinguishable states of a physical system coupled to a thermal environment, and that evolves via a sequence of interactions with an external system holding a physical instantiation of a random input string. The central result, which is shown to follow from quantum dynamics and entropic inequalities alone, can be regarded as a generalization of Landauer's Principle applicable to FSAs and tailorable to specified automata. Application to a simple FSA is illustrated.

  20. General thermodynamic performance of irreversible absorption heat pump

    International Nuclear Information System (INIS)

    Zhao Xiling; Fu Lin; Zhang Shigang

    2011-01-01

    The absorption heat pump (AHP) was studied with thermodynamics. A four reservoirs model of absorption heat pump was established considering the heat resistance, heat leak and the internal irreversibility. The reasonable working regions, the performance effects of irreversibility, heat leak and the correlation of four components were studied. When studying the effects of internal irreversibility, two internal irreversibility parameters (I he for generator-absorber assembly and I re for evaporator-condenser assembly) were introduced to distinguish the different effects. When studying the heat transfer relations of four components, a universal relationship between the main parameters were deduced. The results which have more realized meaning show that, the reduction of the friction, heat loss, and internal dissipations of the evaporator-condenser assembly are more important than its reduction of generator-absorber assembly, and lessening the heat leak of generator are more important than its reduction of other components to improve the AHP performance.

  1. On vectorial irreversible processes in homogeneous isotropic cosmological models

    International Nuclear Information System (INIS)

    Meier, W.

    1990-01-01

    In a given Friedman metric in the framework of usual thermodynamics of irreversible processes, the general relativistic diffusion equation is derived. To give solutions to the equation for special assumptions, the results in a Schroedinger paper are used. (author)

  2. Irreversible pulpitis and achieving profound anesthesia: Complexities and managements

    Science.gov (United States)

    Modaresi, Jalil; Davoudi, Amin; Badrian, Hamid; Sabzian, Roya

    2016-01-01

    Dental pain management is one of the most critical aspects of modern dentistry. Irreversible pulpitis and further root canal therapy might cause an untolerated pain to the patients. The improvements in anesthetic agents and techniques were one of the advantages of studying nerve biology and stimulation. This article tried to overview of the nerve activities in inflammatory environments or induced pain. Furthermore, the proper advises, and supplementary techniques were reviewed for better pain management of irreversible pulpitis. PMID:26957681

  3. Anisotropic shift of the irreversibility line by neutron irradiation

    International Nuclear Information System (INIS)

    Sauerzopf, F.M.; Wiesinger, H.P.; Weber, H.W.; Crabtree, G.W.; Frischherz, M.C.; Kirk, M.A.

    1991-09-01

    The irreversibility line of high-T c superconductors is shifted considerably by irradiating the material with fast neutrons. The anisotropic and non-monotonous shift is qualitatively explained by a simple model based on an interaction between three pinning mechanisms, the intrinsic pinning by the ab-planes, the weak pinning by the pre-irradiation defect structure, and strong pinning by neutron induced defect cascades. A correlation between the cascade density and the position of the irreversibility line is observed

  4. Towards irreversibility with a finite bath of oscillators

    Energy Technology Data Exchange (ETDEWEB)

    De São José, A.N. [Departamento de Engenharia Elétrica, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Dias, P.M. [Programa de Pós-Graduação em Modelagem Matemática e Computacional, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Bosco de Magalhães, A.R., E-mail: arthur.magalhaes@pq.cnpq.br [Programa de Pós-Graduação em Modelagem Matemática e Computacional, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Departamento de Física e Matemática, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); and others

    2012-12-03

    We investigate the routes by which a bath composed of a finite number of oscillators at zero temperature approaches the induction of dissipation when it nears the usual limit of dense spectrum spread in an infinite interval. It is shown that, when this limit is taken, different distributions of environment frequencies can lead to the same irreversible evolution. However, when we move away from it, the dynamics departs from irreversibility in qualitatively different manners.

  5. Methimazole Induced Total Myeloid Aplasia with Delayed Recovery Despite Granulocyte Colony Stimulating Factor (G-CSF): Marrow Progenitor Recovery Kinetics.

    Science.gov (United States)

    Sarker, Tania; Özgönenel, Bülent; Gadgeel, Manisha; Buck, Steven; Adhikari, Amita; Ravindranath, Yaddanapudi

    2016-06-01

    An eighteen-year-old female with Graves thyrotoxicosis presented with methimazole-induced agranulocytosis and total myeloid aplasia. The bone marrow at presentation showed complete absence of myeloid precursors and striking plasmacytosis. 16 days later, myeloid precursors were still absent morphologically; however bone marrow flow cytometry and cell culture detected an improvement in myelogenesis, which was soon followed by clinical recovery of agranulocytosis. Neutrophil recovery was delayed until day 22 after cessation of methimazole despite G-CSF use, consistent with a direct toxic effect on committed myeloid cells. Our findings suggest that cell culture and flow cytometric evaluation of bone marrow myeloid progenitors can be used as a guide to anticipate neutrophil recovery.

  6. Deferasirox treatment improved hematopoiesis and led to complete remission in a patient with pure red cell aplasia.

    Science.gov (United States)

    Kojima, Minoru; Machida, Shinichiro; Sato, Ai; Miyamoto, Mitsuki; Moriuchi, Makiko; Ohbayashi, Yoshiaki; Ando, Kiyoshi

    2013-12-01

    A 64-year-old woman developed pure red cell aplasia (PRCA) 4 years after thymectomy for thymoma. During anti-thymocyte globulin treatment, the patient developed cytomegalovirus pneumonia and was thus unable to continue immunosuppressive therapy and became transfusion dependent. Deferasirox was started for treatment with iron overload when serum ferritin increased to >1000 ng/mL. Seven months after initiation of deferasirox treatment, serum ferritin level decreased the normal range and the patient has remained transfusion independent thereafter. Deferasirox was discontinued when serum ferritin level decreased below 500 ng/mL, and she has maintained in complete remission over the last 15 months. Hypotheses have been raised regarding the improvement of hematopoiesis by deferasirox treatment, but the mechanism whereby this might be achieved remains unclear. Deferasirox treatment may be clinically beneficial both by reducing iron overload and by improving hematopoiesis in patients with PRCA.

  7. Aplasia medular após transplante hepático em pediatria Aplastic anemia after pediatric liver transplantation

    Directory of Open Access Journals (Sweden)

    Marlene P. Garanito

    2009-01-01

    Full Text Available A aplasia de medula é uma das mais raras (Aplastic anemia (AA is one of the rarest (<1% and most serious complications of liver transplantation for fulminant non-A, non-B and non-C hepatitis. It was first described in 1987 by Stock; the mechanism involved is an immunologically mediated condition secondary to an unknown viral infection. The disease is associated with a dismal prognosis. Spontaneous recovery from acquired AA is very rare however some patients (50-70% recover after immunosuppressive therapy, such as Cyclosporin A (CsA and Antithymocyte globulin (ATG, even after liver transplantation. Another treatment option is bone marrow transplantation. We report on a child who developed AA following liver transplantation for fulminant viral hepatitis that was treated with intensive immunosuppression including CsA and ATG and achieved complete recovery.

  8. Attribution of irreversible loss to anthropogenic climate change

    Science.gov (United States)

    Huggel, Christian; Bresch, David; Hansen, Gerrit; James, Rachel; Mechler, Reinhard; Stone, Dáithí; Wallimann-Helmer, Ivo

    2016-04-01

    The Paris Agreement (2015) under the UNFCCC has anchored loss and damage in a separate article which specifies that understanding and support should be enhanced in areas addressing loss and damage such as early warning, preparedness, insurance and resilience. Irreversible loss is a special category under loss and damage but there is still missing clarity over what irreversible loss actually includes. Many negative impacts of climate change may be handled or mitigated by existing risk management, reduction and absorption approaches. Irreversible loss, however, is thought to be insufficiently addressed by risk management. Therefore, countries potentially or actually affected by irreversible loss are calling for other measures such as compensation, which however is highly contested in international climate policy. In Paris (2015) a decision was adopted that loss and damage as defined in the respective article of the agreement does not involve compensation and liability. Nevertheless, it is likely that some sort of mechanism will eventually need to come into play for irreversible loss due to anthropogenic climate change, which might involve compensation, other forms of non-monetary reparation, or transformation. Furthermore, climate litigation has increasingly been attempted to address negative effects of climate change. In this context, attribution is important to understand the drivers of change, what counts as irreversible loss due to climate change, and, possibly, who or what is responsible. Here we approach this issue by applying a detection and attribution perspective on irreversible loss. We first analyze detected climate change impacts as assessed in the IPCC Fifth Assessment Report. We distinguish between irreversible loss in physical, biological and human systems, and accordingly identify the following candidates of irreversible loss in these systems: loss of glaciers and ice sheets, loss of subsurface ice (permafrost) and related loss of lake systems; loss

  9. The incidence of mechanical allodynia in patients with irreversible pulpitis.

    Science.gov (United States)

    Owatz, Christopher B; Khan, Asma A; Schindler, William G; Schwartz, Scott A; Keiser, Karl; Hargreaves, Kenneth M

    2007-05-01

    The mechanisms of odontogenic pain are complex and incompletely understood. Cases of irreversible pulpitis are thought to represent a localized inflammatory response to bacterial challenge in dental pulp tissue. The presenting symptoms are classically defined by exaggerated painful episodes to thermal stimuli that may linger after cessation of the stimulus. However, the associated incidence of mechanical allodynia, defined as reduced mechanical pain threshold to masticatory forces, has not been characterized. This study evaluated pain intensity ratings and the presence of mechanical allodynia reported by 993 consecutive dental patients presenting for tooth extraction in a community health center. After clinical and radiographic examinations, the pulpal/periradicular diagnostic categories were normal pulp/normal periradicular (n=792 patients), irreversible pulpitis/normal periradicular (n=86), or irreversible pulpitis/acute periradicular periodontitis (n=115). The rank order for the mean values of pain intensity ratings was irreversible pulpitis/acute periradicular periodontitis > irreversible pulpitis/normal periradicular > normal/normal (pirreversible pulpitis was 57.2%, indicating that periradicular mechanical allodynia contributes to early stages of odontogenic pain because of inflammation of vital pulpal tissue.

  10. Irreversible climate change due to carbon dioxide emissions.

    Science.gov (United States)

    Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

    2009-02-10

    The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer.

  11. Irreversibility analysis in the process of solar distillation

    Science.gov (United States)

    Chávez, S.; Terres, H.; Lizardi, A.; López, R.; Lara, A.

    2017-01-01

    In this work an irreversibility analysis for the thermal process of solar distillation of three different substances is presented, for which it employs a solar still of a slope where three experimental tests with 5.5 L of brine, river water and MgCl2 were performed. Temperature data principally in the glass cover, absorber plate, fluid, environment and the incident solar radiation on the device were obtained. With measurements of temperature, solar radiation and exergetic balance, irreversibilities are found on the device. The results show that the highest values of irreversibilities are concentrated in the absorber plate with an average of 321 W, 342 W and 276 W, followed by the cover glass with an average of 75.8 W, 80.4 W and 86.7 W and finally the fluid with 15.3 W, 15.9 W and 16 W, for 5.5 L of brine, river water and MgCl2.

  12. Reversible and Irreversible Binding of Nanoparticles to Polymeric Surfaces

    Directory of Open Access Journals (Sweden)

    Wolfgang H. Binder

    2009-01-01

    Full Text Available Reversible and irreversible binding of CdSe-nanoparticles and nanorods to polymeric surfaces via a strong, multiple hydrogen bond (= Hamilton-receptor/barbituric acid is described. Based on ROMP-copolymers, the supramolecular interaction on a thin polymer film is controlled by living polymerization methods, attaching the Hamilton-receptor in various architectures, and concentrations. Strong binding is observed with CdSe-nanoparticles and CdSe-nanorods, whose surfaces are equipped with matching barbituric acid-moieties. Addition of polar solvents, able to break the hydrogen bonds leads to the detachment of the nanoparticles from the polymeric film. Irreversible binding is observed if an azide/alkine-“click”-reaction is conducted after supramolecular recognition of the nanoparticles on the polymeric surface. Thus reversible or irreversible attachment of the nanosized objects can be achieved.

  13. Hydraulically irreversible fouling on ceramic MF/UF membranes: comparison of fouling indices, foulant composition and irreversible pore narrowing

    KAUST Repository

    Shang, Ran

    2015-05-06

    The application of ceramic membranes in water treatment is becoming increasing attractive because of their long life time and excellent chemical, mechanical and thermal stability. However, fouling of ceramic membranes, especially hydraulically irreversible fouling, is still a critical aspect affecting the operational cost and energy consumption in water treatment plants. In this study, four ceramic membranes with pore sizes or molecular weight cut-off (MWCO) of 0.20 μm, 0.14 μm, 300 kDa and 50 kDa were compared during natural surface water filtration with respect to hydraulically irreversible fouling index (HIFI), foulant composition and narrowing of pore size due to the irreversible fouling. Our results showed that the hydraulically irreversible fouling index (HIFI) was proportional to the membrane pore size (r2=0.89) when the same feed water was filtrated. The UF membranes showed lower HIFI values than the MF membranes. Pore narrowing (internal fouling) was found to be a main fouling pattern of the hydraulically irreversible fouling. The internal fouling was caused by monolayer adsorption of foulants with different sizes that is dependent on the size of the membrane pore.

  14. Third Party Cord Blood Transplant Boosts Autologous Hematopoiesis in a Case of Persistent Bone Marrow Aplasia after Double Transplant Failure for B-Thalassemia Major

    OpenAIRE

    Visani, Giuseppe; Picardi, Paola; Guiducci, Barbara; Loscocco, Federica; Giardini, Claudio; Lucesole, Moira; Barulli, Sara; Ricciardi, Teresa; Isidori, Alessandro

    2013-01-01

    A 9-year-old female received an allogeneic stem cell transplant (SCT) from an ABO-incompatible HLA-matched sibling for ?-thalassemia major, without achieving a complete donor chimerism. Subsequently, the patient received five donor lymphocyte infusions, without increasing donor chimerism, and autologous SCT. Due to the persistent bone marrow aplasia, the patient received a second allogeneic SCT from the same donor without obtaining any engrafment. After the double transplant failure, we perfo...

  15. Double inter-internal carotid artery communication through intercavernous anastomosis and posterior communicating artery associated with multiple intracranial artery segmental agenesis/aplasia.

    Science.gov (United States)

    Park, Yae Won; Yoo, Joonsang; Kim, Dong Joon

    2018-02-01

    Segmental internal carotid artery (ICA) and basilar artery (BA) agenesis/aplasia are rare vascular anomalies. We report an extremely rare case of combined ICA, BA, and A1 segmental absence presenting with double inter-ICA collateral communication through the intercavernous anastomosis and posterior communicating arteries. The patient presented with diplopia and transient ischemic attack. The pathogenesis of the anatomic anomalies and clinical symptoms are discussed.

  16. The thermomechanics of nonlinear irreversible behaviors an introduction

    CERN Document Server

    Maugin, Gérard A

    1999-01-01

    In this invaluable book, macroscopic irreversible thermodynamics is presented in its realm and its splendor by appealing to the notion of internal variables of state. This applies to both fluids and solids with or without microstructures of mechanical or electromagnetic origin. This unmatched richness of essentially nonlinear behaviors is the result of the use of modern mathematical techniques such as convex analysis in a clear-cut framework which allows one to put under the umbrella of "irreversible thermodynamics" behaviors which until now have been commonly considered either not easily cove

  17. A new approach to irreversibility in deep inelastic collisions

    International Nuclear Information System (INIS)

    Nemes, M.C.

    1982-01-01

    We use concepts of statistical mechanics to discuss the irreversible character of the experimental data in deep inelastic collisions. A definition of irreversibility proposed by Ruch permits a unified overview on current theories which describe these reactions. An information theoretical analysis of the data leads to a Fokker-Planck equation for the collective variables (excitation energy, charge and mass). The concept of mixing distance can serve as a quantitative measure to characterize the 'approach to equilibrium'. We apply it to the brownian motion as an illustration and also to the phenomenological analysis of deep inelastic scattering data with interesting results. (orig.)

  18. CD19 CAR-targeted T cells induce long-term remission and B Cell Aplasia in an immunocompetent mouse model of B cell acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Marco L Davila

    Full Text Available Although many adults with B cell acute lymphoblastic leukemia (B-ALL are induced into remission, most will relapse, underscoring the dire need for novel therapies for this disease. We developed murine CD19-specific chimeric antigen receptors (CARs and an immunocompetent mouse model of B-ALL that recapitulates the disease at genetic, cellular, and pathologic levels. Mouse T cells transduced with an all-murine CD3ζ/CD28-based CAR that is equivalent to the one being used in our clinical trials, eradicate B-ALL in mice and mediate long-term B cell aplasias. In this model, we find that increasing conditioning chemotherapy increases tumor eradication, B cell aplasia, and CAR-modified T cell persistence. Quantification of recipient B lineage cells allowed us to estimate an in vivo effector to endogenous target ratio for B cell aplasia maintenance. In mice exhibiting a dramatic B cell reduction we identified a small population of progenitor B cells in the bone marrow that may serve as a reservoir for long-term CAR-modified T cell stimulation. Lastly, we determine that infusion of CD8+ CAR-modified T cells alone is sufficient to maintain long-term B cell eradication. The mouse model we report here should prove valuable for investigating CAR-based and other therapies for adult B-ALL.

  19. What Nigerian ophthalmologists do for their irreversibly blind patients

    African Journals Online (AJOL)

    The diagnosis of irreversible blindness (IB) is a traumatic one for both the ophthalmologist and the patient, because of the finality of the patient's loss of sight. There are supportive measures that an ophthalmologist could provide to ensure a dignified and productive life for the blind patient. This communication examines the ...

  20. Parametric optimum analysis of an irreversible Ericsson cryogenic ...

    Indian Academy of Sciences (India)

    An irreversible model of an Ericsson cryogenic refrigeration cycle working with an ideal Fermi gas is established, which is composed of two isothermal and two ... University, Xiamen 361005, People's Republic of China; Department of Physics, Quanzhou Normal University, Quanzhou 362000, People's Republic of China ...

  1. Minimum energy dissipation required for a logically irreversible operation

    Science.gov (United States)

    Takeuchi, Naoki; Yoshikawa, Nobuyuki

    2018-01-01

    According to Landauer's principle, the minimum heat emission required for computing is linked to logical entropy, or logical reversibility. The validity of Landauer's principle has been investigated for several decades and was finally demonstrated in recent experiments by showing that the minimum heat emission is associated with the reduction in logical entropy during a logically irreversible operation. Although the relationship between minimum heat emission and logical reversibility is being revealed, it is not clear how much free energy is required to be dissipated for a logically irreversible operation. In the present study, in order to reveal the connection between logical reversibility and free energy dissipation, we numerically demonstrated logically irreversible protocols using adiabatic superconductor logic. The calculation results of work during the protocol showed that, while the minimum heat emission conforms to Landauer's principle, the free energy dissipation can be arbitrarily reduced by performing the protocol quasistatically. The above results show that logical reversibility is not associated with thermodynamic reversibility, and that heat is not only emitted from logic devices but also absorbed by logic devices. We also formulated the heat emission from adiabatic superconductor logic during a logically irreversible operation at a finite operation speed.

  2. Exergetic efficiency optimization for an irreversible heat pump ...

    Indian Academy of Sciences (India)

    The irreversibilities considered in the system include heat resistance losses in the hot- and cold-side heat exchangers and non-isentropic losses in the compression and expansion processes. The analytical formulas of the heating load, coefficient of performance (COP) and exergetic efficiency for the heat pumps are derived ...

  3. Exergetic efficiency optimization for an irreversible heat pump ...

    Indian Academy of Sciences (India)

    This paper deals with the performance analysis and optimization for irreversible heat pumps working on reversed Brayton cycle with constant-temperature heat reservoirs by taking exergetic efficiency as the optimization objective combining exergy concept with finite-time thermodynamics (FTT). Exergetic efficiency is ...

  4. Profit rate performance optimization for a generalized irreversible ...

    Indian Academy of Sciences (India)

    The operation of the generalized irreversible combined refrigeration cycle is viewed as a production process with exergy as its output. The performance optimization of the cycle is performed by taking profit as the objective. The optimal profit rate, optimal COP (coefficient of performance), as well as the relation between the ...

  5. Profit rate performance optimization for a generalized irreversible ...

    Indian Academy of Sciences (India)

    engineering economic optimization to evaluate and optimize the design and performance of energy systems is ... paper is to study the finite time exergoeconomic performance of the generalized irreversible combined refrigeration cycle. ..... qualitative differences are as following: when 0 ≤ ψ2/ψ1 ≤ 0·033, the curves of π − ε.

  6. Parametric optimum analysis of an irreversible Ericsson cryogenic ...

    Indian Academy of Sciences (India)

    on the heat-transfer law and the heat conductances. It is often assumed that heat. 780. Pramana – J. ... an irreversible Fermi–. Ericsson refrigeration cycle. transfer obeys Newton's law [25], i.e., ...... [20] P K Pathria, Statistical mechanics 2nd edition (Elsevier Pvt Ltd, Singapore, 1996). [21] K Huang, Statistical mechanics 2nd ...

  7. Sector of West Antarctic Ice Sheet in "Irreversible Retreat"

    Science.gov (United States)

    Showstack, Randy

    2014-05-01

    A large sector of the West Antarctic Ice Sheet "has gone into a state of irreversible retreat," according to glaciologist Eric Rignot, lead author of the paper "Widespread rapid grounding line retreat of Pine Island, Thwaites, Smith, and Kohler Glaciers in West Antarctica from 1992 to 2011," which has been accepted for publication in Geophysical Research Letters (GRL).

  8. The degree of irreversibility in deterministic finite automata

    DEFF Research Database (Denmark)

    Axelsen, Holger Bock; Holzer, Markus; Kutrib, Martin

    2016-01-01

    for nondeterministic finite state automata (NFA) is PSPACE-complete. The recent DFA method essentially works by minimizing the DFA and inspecting it for a forbidden pattern. We here study the degree of irreversibility for a regular language, the minimal number of such forbidden patterns necessary in any DFA accepting...

  9. A criterion to maximize the irreversible efficiency in heat engines

    CERN Document Server

    Aragon-Gonzalez, G; Leon-Galicia, A; Musharrafie-Martinez, M

    2003-01-01

    The purpose of this work is to obtain a more precise calculation of the effective limits to the efficiency, of several cyclic heat engines. This calculation is based, first, on the equations describing the irreversible efficiency, and second, on a method which results from a general criterion to maximize this efficiency, applicable to several heat engines. With this method, we apply the criterion to maximize efficiencies; establish lower and upper bounds, corresponding to the efficiencies of Curzon-Ahlborn-like and Carnot-like heat engines; and, finally, find analytical or numerical expressions for the efficiencies eta sub m sub e and eta sub m sub a sub x. eta sub m sub a sub x is the maximum irreversible efficiency; eta sub m sub e is the efficiency in which the irreversible efficiency achieves its maximum, in a similar way to the Curzon-Ahlborn efficiency (maximum work or power). The method was applied to a Brayton cycle, presenting internal dissipations of the working fluid and irreversibilities due to th...

  10. Reversible and irreversible reaction fronts in two competing reactions system

    International Nuclear Information System (INIS)

    Sinder, M.; Taitelbaum, H.; Pelleg, J.

    2002-01-01

    A modeling of the non-equilibrium diffusion phenomena of the impurities in the semiconductors is based on the reaction-diffusion equations for local concentrations of the components. Through this approach a new feature, a reaction front, may be caused by reaction in diffusion profiles of the components. The asymptotic long-time properties of the reaction fronts in the system with initially separated components and two competing reactions: reversible A 1 +B↔C 1 and irreversible A 2 +B→C 2 are studied in this work. It is assumed that the backward constant of the reaction A 1 +B↔C 1 is small. The dynamics of the system is described as a cross-over between the 'irreversible' regime for small times and the 'reversible' regime for large times. It is shown that the 'irreversible' regime is characterized by single reaction zone, in which both reactions occur. The two reaction fronts, reversible A 1 +B↔C 1 and irreversible A 2 +C 1 →A 1 +C 2 appear in the 'reversible' regime. Numerical computing of the mean-field kinetics equations confirms these asymptotic results. The experimental tests of the theoretical predictions relating to the diffusion phenomena in semiconductors are discussed

  11. [Thymoma Associated with Pure Red Cell Aplasia Treated with Ciclosporin as Remission-induction Therapy before Thymectomy].

    Science.gov (United States)

    Kawakami, Toru; Ishida, Itaru; Yoshimura, Ryuichi; Sugawara, Takafumi; Oura, Hiroyuki; Miyairi, Yasuro

    2015-06-01

    A thymoma with pure red cell aplasia( PRCA) is relatively rare, and the treatment of the disease has not established yet. We describe a case of a thymoma associated with PRCA treated with a surgery and remission-induction therapy by ciclosporin. An 80-year-old man complained of dizziness and his blood cell count showed a severe anemia. He was diagnosed as PRCA by bone-marrow aspiration biopsy, which showed abatement of erythroblasts. In addition, the chest computed tomography revealed a solid tumor in the anterior mediastinum, strongly suggesting a thymoma. Oral administration of ciclosporin as remission-induction therapy for PRCA was started at 1st. The treatment contributed to partial remission for PRCA without blood transfusion. Consecutively thymectomy through median sternotomy was performed at 6 weeks after initiation of the treatment without any transfusions or complications. Histology of the solid tumor showed the thymoma of type B2 in World Health Organization (WHO) category. We continued to treat PRCA with ciclosporin after the surgery. The patient has been surviving for 2 years after surgery without any recurrence of thymoma or relapse of anemia. Combined therapy of surgery and remission-induction therapy with ciclosporin assumed to be a good strategy of the treatment for the patient with a thymoma associated with PRCA.

  12. BNNT-mediated irreversible electroporatio: its potential on cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Vittoria Raffa, Cristina Riggio, Michael W. Smith, Kevin C. Jordan, Wei Cao, Alfred Cuschieri

    2012-10-01

    Tissue ablation, i.e., the destruction of undesirable tissues, has become an important minimally invasive technique alternative to resection surgery for the treatment of tumours. Several methods for tissue ablation are based on thermal techniques using cold, e.g. cryosurgery [1] or heat, e.g. radiofrequency [2] or high-intensity focused ultrasound [3] or nanoparticle-mediated irradiation [4]. Alternatively, irreversible electroporation (IRE) has been proposed as non thermal technique for minimally invasive tissue ablation based on the use of electrical pulses. When the electric field is applied to a cell, a change in transmembrane potential is induced, which can cause biochemical and physiological changes of the cell. When the threshold value of the transmembrane potential is exceeded, the cell membrane becomes permeable, thus allowing entrance of molecules that otherwise cannot cross the membrane [5]. A further increase in the electric field intensity may cause irreversible membrane permeabilization and cell death. These pulses create irreversible defects (pores) in the cell membrane lipid bilayer, causing cell death through loss of cell homeostasis [6]. This is desirable in tumour ablation in order to produce large cell death, without the use of cytostatic drugs. A study of Davalos, Mir and Rubinsky showed that IRE can ablate substantial volumes of tissue without inducing a thermal effect and therefore serve as an independent and new tissue ablation modality; this opened the way to the use of IRE in surgery [7]. Their finding was subsequently confirmed in studies on cells [8], small animal models [9] and in large animal models in the liver [10] and the heart [11]. The most important finding in these papers is that irreversible electroporation produces precisely delineated ablation zones with cell scale resolution between ablated and non-ablated areas, without zones in which the extent of damage changes gradually as during thermal ablation. Furthermore, it is

  13. Ecological optimization for an irreversible magnetic Ericsson refrigeration cycle

    Science.gov (United States)

    Wang, Hao; Wu, Guo-Xing

    2013-08-01

    An irreversible Ericsson refrigeration cycle model is established, in which multi-irreversibilities such as finite-rate heat transfer, regenerative loss, heat leakage, and the efficiency of the regenerator are taken into account. Expressions for several important performance parameters, such as the cooling rate, coefficient of performance (COP), power input, exergy output rate, entropy generation rate, and ecological function are derived. The influences of the heat leakage and the time of the regenerative processes on the ecological performance of the refrigerator are analyzed. The optimal regions of the ecological function, cooling rate, and COP are determined and evaluated. Furthermore, some important parameter relations of the refrigerator are revealed and discussed in detail. The results obtained here have general significance and will be helpful in gaining a deep understanding of the magnetic Ericsson refrigeration cycle.

  14. Irreversible adsorption of phenolic compounds by activated carbons

    Energy Technology Data Exchange (ETDEWEB)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs.

  15. Prostaglandin E2 to diagnose between reversible and irreversible pulpitis.

    Science.gov (United States)

    Petrini, M; Ferrante, M; Ciavarelli, L; Brunetti, L; Vacca, M; Spoto, G

    2012-01-01

    The aim of this work is to verify a correlation between the grade of inflammation and the concentration of PGE2 in human dental pulp. A total of 25 human dental pulps were examined by histological analysis and radioimmunologic dosage of PGE2. The pulps used in this experiment were from healthy and symptomatic teeth; the first ones were collected from teeth destined to be extracted for orthodontic reasons. An increase was observed of PGE2 in reversible pulpitis compared with healthy pulps and with the irreversible pulpitis and the clear decrease of these when NSAIDs are taken. This study demonstrates that PGE2 level is correlated to histological analysis thus allowing to distinguish symptomatic teeth in reversible and irreversible pulpitis.

  16. Microscopic theory for the time irreversibility and the entropy production

    Science.gov (United States)

    Chun, Hyun-Myung; Noh, Jae Dong

    2018-02-01

    In stochastic thermodynamics, the entropy production of a thermodynamic system is defined by the irreversibility measured by the logarithm of the ratio of the path probabilities in the forward and reverse processes. We derive the relation between the irreversibility and the entropy production starting from the deterministic equations of motion of the whole system consisting of a physical system and a surrounding thermal environment. The derivation assumes the Markov approximation that the environmental degrees of freedom equilibrate instantaneously. Our approach provides a guideline for the choice of the proper reverse process to a given forward process, especially when there exists a velocity-dependent force. We demonstrate our idea with an example of a charged particle in the presence of a time-varying magnetic field.

  17. Thermodynamic Analysis of the Irreversibilities in Solar Absorption Refrigerators

    Directory of Open Access Journals (Sweden)

    Emma Berrich Betouche

    2016-03-01

    Full Text Available A thermodynamic analysis of the irreversibility on solar absorption refrigerators is presented. Under the hierarchical decomposition and the hypothesis of an endoreversible model, many functional and practical domains are defined. The effect of external heat source temperature on the entropy rate and on the inverse specific cooling load (ISCL multiplied by the total area of the refrigerator A/Qe are studied. This may help a constructor to well dimension the solar machine under an optimal technico-economical criterion A/Qe and with reasonable irreversibility on the refrigerator. The solar concentrator temperature effect on the total exchanged area, on the technico-economical ratio A/Qe, and on the internal entropy rate are illustrated and discussed. The originality of these results is that they allow a conceptual study of a solar absorption refrigeration cycle.

  18. Irreversible adsorption of phenolic compounds by activated carbons

    International Nuclear Information System (INIS)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs

  19. Reversing the irreversible: From limit cycles to emergent time symmetry

    Science.gov (United States)

    Cortês, Marina; Smolin, Lee

    2018-01-01

    In 1979 Penrose hypothesized that the arrows of time are explained by the hypothesis that the fundamental laws are time irreversible [R. Penrose, in General Relativity: An Einstein Centenary Survey (1979)]. That is, our reversible laws, such as the standard model and general relativity are effective, and emerge from an underlying fundamental theory which is time irreversible. In [M. Cortês and L. Smolin, Phys. Rev. D 90, 084007 (2014), 10.1103/PhysRevD.90.084007; 90, 044035 (2014), 10.1103/PhysRevD.90.044035; 93, 084039 (2016), 10.1103/PhysRevD.93.084039] we put forward a research program aiming at realizing just this. The aim is to find a fundamental description of physics above the Planck scale, based on irreversible laws, from which will emerge the apparently reversible dynamics we observe on intermediate scales. Here we continue that program and note that a class of discrete dynamical systems are known to exhibit this very property: they have an underlying discrete irreversible evolution, but in the long term exhibit the properties of a time reversible system, in the form of limit cycles. We connect this to our original model proposal in [M. Cortês and L. Smolin, Phys. Rev. D 90, 084007 (2014), 10.1103/PhysRevD.90.084007], and show that the behaviors obtained there can be explained in terms of the same phenomenon: the attraction of the system to a basin of limit cycles, where the dynamics appears to be time reversible. Further than that, we show that our original models exhibit the very same feature: the emergence of quasiparticle excitations obtained in the earlier work in the space-time description is an expression of the system's convergence to limit cycles when seen in the causal set description.

  20. Irreversible pulpitis and achieving profound anesthesia: Complexities and managements

    OpenAIRE

    Modaresi, Jalil; Davoudi, Amin; Badrian, Hamid; Sabzian, Roya

    2016-01-01

    Dental pain management is one of the most critical aspects of modern dentistry. Irreversible pulpitis and further root canal therapy might cause an untolerated pain to the patients. The improvements in anesthetic agents and techniques were one of the advantages of studying nerve biology and stimulation. This article tried to overview of the nerve activities in inflammatory environments or induced pain. Furthermore, the proper advises, and supplementary techniques were reviewed for better pain...

  1. Irreversibility and chaos: role of lubrication interactions in sheared suspensions.

    Science.gov (United States)

    Metzger, Bloen; Pham, Phong; Butler, Jason E

    2013-05-01

    We investigate non-Brownian particles suspended in a periodic shear-flow using simulations. Following Metzger and Butler [Phys. Rev. E 82, 051406 (2010)], we show that the chaotic dynamics arising from lubrication interactions are too weak to generate an observable particle dispersion. The irreversibility observed in periodic flow is dominated by contact interactions. Nonetheless, we show that lubrication interactions must be included in the calculation to obtain results that agree with experiments.

  2. Sacrificial salts: Compensating the initial charge irreversibility in lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shanmukaraj, Devaraj; Grugeon, Sylvie; Laruelle, Stephane; Douglade, Gregory; Tarascon, Jean-Marie; Armand, Michel [Laboratoire de Reactivite et de Chimie des Solides, UMR CNRS 6007, Universite de Picardie Jules Verne, Amiens (France)

    2010-10-15

    Lithium salts enlisting azide, oxocarbons, dicarboxylates and hydrazides have been identified as a practical mean to compensate the irreversible capacity loss of LIBs negative electrodes. During the first charge, the anion loses electrons and converts to gaseous N{sub 2}, CO or CO{sub 2}, within an acceptable potential range (3 to 4.5 V). We report an electrochemical study on these easily accessible 'sacrificial salts'. (author)

  3. Irreversibility and complex network behavior of stream flow fluctuations

    Science.gov (United States)

    Serinaldi, Francesco; Kilsby, Chris G.

    2016-05-01

    Exploiting the duality between time series and networks, directed horizontal visibility graphs (DHVGs) are used to perform an unprecedented analysis of the dynamics of stream flow fluctuations with focus on time irreversibility and long range dependence. The analysis relies on a large quality-controlled data set consisting of 699 daily time series recorded in the continental United States (CONUS) that are not affected by human activity and primarily reflects meteorological conditions. DHVGs allow a clear visualization and quantification of time irreversibility of flow dynamics, which can be interpreted as a signature of nonlinearity, and long range dependence resulting from the interaction of atmospheric, surface and underground processes acting at multiple spatio-temporal scales. Irreversibility is explored by mapping the time series into ingoing, outgoing, and undirected graphs and comparing the corresponding degree distributions. Using surrogate data preserving up to the second order linear temporal dependence properties of the observed series, DHVGs highlight the additional complexity introduced by nonlinearity into flow fluctuation dynamics. We show that the degree distributions do not decay exponentially as expected, but tend to follow a subexponential behavior, even though sampling uncertainty does not allow a clear distinction between apparent or true power law decay. These results confirm that the complexity of stream flow dynamics goes beyond a linear representation involving for instance the combination of linear processes with short and long range dependence, and requires modeling strategies accounting for temporal asymmetry and nonlinearity.

  4. Irreversible Local Markov Chains with Rapid Convergence towards Equilibrium

    Science.gov (United States)

    Kapfer, Sebastian C.; Krauth, Werner

    2017-12-01

    We study the continuous one-dimensional hard-sphere model and present irreversible local Markov chains that mix on faster time scales than the reversible heat bath or Metropolis algorithms. The mixing time scales appear to fall into two distinct universality classes, both faster than for reversible local Markov chains. The event-chain algorithm, the infinitesimal limit of one of these Markov chains, belongs to the class presenting the fastest decay. For the lattice-gas limit of the hard-sphere model, reversible local Markov chains correspond to the symmetric simple exclusion process (SEP) with periodic boundary conditions. The two universality classes for irreversible Markov chains are realized by the totally asymmetric SEP (TASEP), and by a faster variant (lifted TASEP) that we propose here. We discuss how our irreversible hard-sphere Markov chains generalize to arbitrary repulsive pair interactions and carry over to higher dimensions through the concept of lifted Markov chains and the recently introduced factorized Metropolis acceptance rule.

  5. Irreversible performance of a quantum harmonic heat engine

    Science.gov (United States)

    Rezek, Yair; Kosloff, Ronnie

    2006-05-01

    The unavoidable irreversible loss of power in a heat engine is found to be of quantum origin. Following thermodynamic tradition, a model quantum heat engine operating in an Otto cycle is analysed, where the working medium is composed of an ensemble of harmonic oscillators and changes in volume correspond to changes in the curvature of the potential well. Equations of motion for quantum observables are derived for the complete cycle of operation. These observables are sufficient to determine the state of the system and with it all thermodynamical variables. Once the external controls are set, the engine settles to a limit cycle. Conditions for optimal work, power and entropy production are derived. At high temperatures and quasistatic operating conditions, the efficiency at maximum power coincides with the endoreversible result \\eta_q=1-\\sqrt{{T_c}/{T_h}} . The optimal compression ratio varies from {\\cal C} =\\sqrt{T_h/T_c} in the quasistatic limit where the irreversibility is dominated by heat conductance to {\\cal C} =(T_h/T_c)^{1/4} in the sudden limit when the irreversibility is dominated by friction. When the engine deviates from adiabatic conditions, the performance is subject to friction. The origin of this friction can be traced to the noncommutability of the kinetic and potential energy of the working medium.

  6. Anesthetic Efficacy in Irreversible Pulpitis: A Randomized Clinical Trial.

    Science.gov (United States)

    Allegretti, Carlos E; Sampaio, Roberta M; Horliana, Anna C R T; Armonia, Paschoal L; Rocha, Rodney G; Tortamano, Isabel Peixoto

    2016-01-01

    Inferior alveolar nerve block has a high failure rate in the treatment of mandibular posterior teeth with irreversible pulpitis. The aim of this study was to compare the anesthetic efficacy of 4% articaine, 2% lidocaine and 2% mepivacaine, all in combination with 1:100,000 epinephrine, in patients with irreversible pulpitis of permanent mandibular molars during a pulpectomy procedure. Sixty-six volunteers from the Emergency Center of the School of Dentistry, University of São Paulo, randomly received 3.6 mL of local anesthetic as a conventional inferior alveolar nerve block (IANB). The subjective signal of lip numbness, pulpal anesthesia and absence of pain during the pulpectomy procedure were evaluated respectively, by questioning the patient, stimulation using an electric pulp tester and a verbal analogue scale. All patients reported the subjective signal of lip numbness. Regarding pulpal anesthesia success as measured with the pulp tester, the success rate was respectively 68.2% for mepivacaine, 63.6% for articaine and 63.6% for lidocaine. Regarding patients who reported no pain or mild pain during the pulpectomy, the success rate was, respectively 72.7% for mepivacaine, 63.6% for articaine and 54.5% for lidocaine. These differences were not statistically significant. Neither of the solutions resulted in 100% anesthetic success in patients with irreversible pulpitis of mandibular molars.

  7. Irreversibility analysis in the process of solar distillation

    International Nuclear Information System (INIS)

    Chávez, S; Terres, H; Lizardi, A; López, R; Lara, A

    2017-01-01

    In this work an irreversibility analysis for the thermal process of solar distillation of three different substances is presented, for which it employs a solar still of a slope where three experimental tests with 5.5 L of brine, river water and MgCl 2 were performed. Temperature data principally in the glass cover, absorber plate, fluid, environment and the incident solar radiation on the device were obtained. With measurements of temperature, solar radiation and exergetic balance, irreversibilities are found on the device. The results show that the highest values of irreversibilities are concentrated in the absorber plate with an average of 321 W, 342 W and 276 W, followed by the cover glass with an average of 75.8 W, 80.4 W and 86.7 W and finally the fluid with 15.3 W, 15.9 W and 16 W, for 5.5 L of brine, river water and MgCl 2 . (paper)

  8. Irreversible dynamics, Onsager-Casimir symmetry, and an application to turbulence.

    Science.gov (United States)

    Ottinger, Hans Christian

    2014-10-01

    Irreversible contributions to the dynamics of nonequilibrium systems can be formulated in terms of dissipative, or irreversible, brackets. We discuss the structure of such irreversible brackets in view of a degeneracy implied by energy conservation, where we consider different types of symmetries of the bracket corresponding to the Onsager and Casimir symmetries of linear irreversible thermodynamics. Slip and turbulence provide important examples of antisymmetric irreversible brackets and offer guidance for the more general modeling of irreversible dynamics without entropy production. Conversely, turbulence modeling could benefit from elucidating thermodynamic structure. The examples suggest constructing antisymmetric irreversible brackets in terms of completely antisymmetric functions of three indices. Irreversible brackets without well-defined symmetry properties can arise for rare events, causing big configurational changes.

  9. RADIOLOGICAL FINDINGS IN COCHLEAR IMPLANT CASES IN PRELINGUAL DEAFNESS- A STUDY AND ANALYSIS OF MICHEL’S APLASIA AND ITS VARIATIONS

    Directory of Open Access Journals (Sweden)

    Bharathi Mohan Mathan

    2017-04-01

    Full Text Available BACKGROUND The incidence of Prelingual deafness with bilateral profound sensory neural hearing loss varies among different regions with overall prevalence rate of one case per 1000 live births. Overall, there are more than 40 million such children all over the World. Hearing losses may be genetic or non-genetic. Genetic hearing losses (50% may be syndromic (15% or nonsyndromic (35%. Genetic hearing loss may be Autosomal or X-linked, Dominant or Recessive, Syndromic or Non-Syndromic. Adequate radiological assessment and confirmation of select cases is utmost important before proceeding to cochlear implant surgery. This study aims at a statistical analysis of various radiological presentation in bilateral profound sensory neural hearing loss in prelingual deafness children selected for cochlear implant in our Institution for a period of one year from January 2016 to January 2017, with study and analysis of Michel’s Aplasia and its variations included in the study. MATERIALS AND METHODS The study is done as a retrospective study at Vellore Medical College at the ENT Department for a period of one year from Jan 2016- Jan 2017, based on the radiological presentation of 20 children included in the study group with other prior investigations. Interpretation was done based on the inner ear anomalies and individual variations are analysed. Study Design- Retrospective study. RESULTS Radiological analysis of 20 cases included in the study group of Prelingual deafness candidates with bilateral profound sensory neural hearing loss selected for cochlear implant showed that three cases had Michel’s Aplasia with individual radiological variations which were analysed, while other cases had radiologically normal middle and inner ear. CONCLUSION Inner ear anomalies of children with bilateral profound sensory neural hearing loss are variable. Although, incomplete partition type and cochlear Hypoplasia type are common according to International studies, Michel

  10. Appearance of ocular vestibular evoked myogenic potential elicited by bone-conducted vibration in a patient with CHARGE syndrome with aplasia of all semicircular canals.

    Science.gov (United States)

    Zhang, Qing; Kaga, Kimitaka; Takegoshi, Hideki; Matsuda, Takeshi

    2014-03-01

    We report VEMP results in a patient with aplasia of bilateral semicircular canals and a small vestibular cavity. The patient was a 27-year-old male. The computed tomograph showed absolutely no formation of his semicircular canals, together with hypoplasia of his vestibular cavity and cochlea in both ears. His oVEMP was recorded near the extraocular muscles on the left side when elicited by BCV in the Fz. The clinical profile of this patient suggested that oVEMP elicited by BCV recorded near the extraocular muscles originated from otolithic end organs, and not from semicircular canal afferents. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. A case of extensive Aplasia Cutis Congenita with underlying skull defect and central nervous system malformation: discussion of large skin defects, complications, treatment and outcome.

    Science.gov (United States)

    Burkhead, A; Poindexter, G; Morrell, D S

    2009-08-01

    Aplasia Cutis Congenita (ACC) is a rare condition characterized by the absence of a portion of skin at birth. Skin defects are usually small (0.5 to 3 cm) and located on the scalp. Although there can be other physical or genetic abnormalities, ACC is most often a benign isolated condition. Rarely is an underlying bony defect present, and this association increases the rate of complications. We report a case of a newborn male with ACC of the entire crown and vertex scalp, non-ossified parietal skull and dysplastic corpus callosum. The patient's skull and skin defects were treated non-surgically, and he recovered well.

  12. Dimensional Stability of Color-Changing Irreversible Hydrocolloids after Disinfection

    Directory of Open Access Journals (Sweden)

    Khaledi AAR

    2015-03-01

    Full Text Available Statement of Problem: Disinfection of dental impressions is a weak point in the dental hygiene chain. In addition, dental office personnel and dental technicians are endangered by cross-contamination. Objectives: This study aimed to investigate the dimensional stability of two color-changing irreversible hydrocolloid materials (IH after disinfection with glutaraldehyde. Materials and Methods: In this in vitro study, impressions were made of a master maxillary arch containing three reference inserts on the occlucal surface of the left and right maxillary second molars and in the incisal surface of the maxillary central incisors. Two types of color-changing irreversible hydrocolloid (tetrachrom, cavex were used. Glutaraldehyde 2% was used in two methods of spraying and immersion to disinfect the impressions. The control group was not disinfected. Casts were made of type IV gypsum. The linear dimensional change of the stone casts was measured with a profile projector. For statistical analysis, Kruskall-Wallis and Mann-Witney tests were used (α=0.05. Results: By immersion method, the casts fabricated from tetrachrom were 0.36% larger in the anteroposterior (AP and 0.05% smaller in cross arch (CA dimensions; however, the casts prepared after spraying of tetrachrom were 0.44% larger in the AP and 0.10% smaller in CA dimensions. The casts made from Cavex were 0.05% smaller in the AP and 0.02% smaller in CA dimensions after spraying and 0.01% smaller in the AP and 0.003% smaller in CA dimensions after immersion. Generally there were not significant differences in AP and CA dimensions of the experimental groups compared to the control (p > 0.05. Conclusions: Disinfection of the tested color-changing irreversible hydrocolloids by glutaraldahyde 2% did not compromise the accuracy of the obtained casts.

  13. Determining the complex modulus of alginate irreversible hydrocolloid dental material.

    Science.gov (United States)

    King, Shalinie; See, Howard; Thomas, Graham; Swain, Michael

    2008-11-01

    The aim of the study is to investigate the visco-elastic response of an alginate irreversible hydrocolloid dental impression material during setting. A novel squeeze film Micro-Fourier Rheometer (MFR, GBC Scientific Equipment, Australia) was used to determine the complex modulus of an alginate irreversible hydrocolloid dental impression material (Algident, ISO 1563 Class A Type 1, Dentalfarm Australia Pty. Ltd.) during setting after mixing. Data was collected every 30s for 10 min in one study and every 10 min for a total of 60 min in another study. A high level of repeatability was observed. The results indicate that the MFR is capable of recording the complex shear modulus of alginate irreversible hydrocolloid for 60 min from the start of mixing and to simultaneously report the changing visco-elastic parameters at all frequencies between 1 Hz and 100 Hz. The storage modulus shows a dramatic increase to 370% of its starting value after 6 min and then reduces to 55% after 60 min. The loss modulus increases to a maximum of 175% of its starting value after 10 min and then reduces to 94% after 60 min. The MFR enables the changes in the complex modulus through the complete setting process to be followed. It is anticipated this approach may provide a better method to compare the visco-elastic properties of impression materials and assist with identification of optimum types for different clinical requirements. The high stiffness of the instrument and the use of band-limited pseudo-random noise as the input signal are the main advantages of this technique over conventional rheometers for determining the changes in alginate visco-elasticity.

  14. Extended irreversible thermodynamics and non-equilibrium temperature

    Directory of Open Access Journals (Sweden)

    Casas-Vazquez, Jose'

    2008-02-01

    Full Text Available We briefly review the concept of non-equilibrium temperature from the perspectives of extended irreversible thermodynamics, fluctuation theory, and statistical mechanics. The relations between different proposals are explicitly examined in two especially simple systems: an ideal gas in steady shear flow and a forced harmonic oscillator in a thermal bath. We examine with special detail temperatures related to the average molecular kinetic energy along different spatial directions, to the average configurational energy, to the derivative of the entropy with respect to internal energy, to fluctuation-dissipation relation and discuss their measurement.

  15. IRREVERSIBILITY GENERATION IN SUGAR, ALCOHOL AND BIOGAS INTEGRATED PRODUCTIONS

    Directory of Open Access Journals (Sweden)

    Meilyn González Cortés

    2017-01-01

    Full Text Available In this work, the stages of losses and lower exergetic efficiency are determined when the sugar production process is integrated with others for the production of products such as biogas, torula yeast and electricity. The study is carried out in three scenarios of integrated processes for obtaining the indicated products. A sugar factory in which sugar and electricity are produced is considered as the base scenario and from this; a second scenario is inferred in which alcohol is produced from the molasses of the sugar process and biogas from the vinasse of the alcohol distillation process. Finally, a third scenario is exergetically evaluated in which sugar, electricity, biogas and alcohol are produced, but this last one from juices and molasses of the sugar process. For the exergetic analysis the integrated scheme was divided into 8 subsystems. From the analysis of results, the major subsystems that generate irreversibilities are: cogeneration (64.36-65.98%, juice extraction (8.85-9.85%, crystallization and cooking, (8.48 -9.02%, fermentation (4.12-4.94% and distillation (2.74-3.2%. Improvements are proposed to minimize irreversibilities, including the thermal integration of processes, technological modifications in the fermentation process and the introduction of more efficient equipment for the generation of electricity. The exergetic efficiency is between 78.95-81.10%, obtaining greater exergetic efficiency in the scheme of joint operation to produce sugar, alcohol and biogas.

  16. Irreversible entropy model for damage diagnosis in resistors

    International Nuclear Information System (INIS)

    Cuadras, Angel; Crisóstomo, Javier; Ovejas, Victoria J.; Quilez, Marcos

    2015-01-01

    We propose a method to characterize electrical resistor damage based on entropy measurements. Irreversible entropy and the rate at which it is generated are more convenient parameters than resistance for describing damage because they are essentially positive in virtue of the second law of thermodynamics, whereas resistance may increase or decrease depending on the degradation mechanism. Commercial resistors were tested in order to characterize the damage induced by power surges. Resistors were biased with constant and pulsed voltage signals, leading to power dissipation in the range of 4–8 W, which is well above the 0.25 W nominal power to initiate failure. Entropy was inferred from the added power and temperature evolution. A model is proposed to understand the relationship among resistance, entropy, and damage. The power surge dissipates into heat (Joule effect) and damages the resistor. The results show a correlation between entropy generation rate and resistor failure. We conclude that damage can be conveniently assessed from irreversible entropy generation. Our results for resistors can be easily extrapolated to other systems or machines that can be modeled based on their resistance

  17. Voter model with arbitrary degree dependence: clout, confidence and irreversibility

    Science.gov (United States)

    Fotouhi, Babak; Rabbat, Michael G.

    2014-03-01

    The voter model is widely used to model opinion dynamics in society. In this paper, we propose three modifications to incorporate heterogeneity into the model. We address the corresponding oversimplifications of the conventional voter model which are unrealistic. We first consider the voter model with popularity bias. The influence of each node on its neighbors depends on its degree. We find the consensus probabilities and expected consensus times for each of the states. We also find the fixation probability, which is the probability that a single node whose state differs from every other node imposes its state on the entire system. In addition, we find the expected fixation time. Then two other extensions to the model are proposed and the motivations behind them are discussed. The first one is confidence, where in addition to the states of neighbors, nodes take their own state into account at each update. We repeat the calculations for the augmented model and investigate the effects of adding confidence to the model. The second proposed extension is irreversibility, where one of the states is given the property that once nodes adopt it, they cannot switch back. This is motivated by applications where, agents take an irreversible action such as seeing a movie, purchasing a music album online, or buying a new product. The dynamics of densities, fixation times and consensus times are obtained.

  18. Influence of delayed pouring on irreversible hydrocolloid properties

    Directory of Open Access Journals (Sweden)

    Stéfani Becker Rodrigues

    2012-10-01

    Full Text Available The aim of this study was to evaluate the physical properties of irreversible hydrocolloid materials poured immediately and after different storage periods. Four alginates were tested: Color Change (Cavex; Hydrogum (Zhermack; Hydrogum 5 (Zhermack; and Hydro Print Premium (Coltene. Their physical properties, including the recovery from deformation (n = 3, compressive strength (n = 3, and detail reproduction and gypsum compatibility (n = 3, were analyzed according to ANSI/ADA specification no. 18. Specimens were stored at 23ºC and humidity and were then poured with gypsum immediately and after 1, 2, 3, 4, and 5 days. The data were analyzed by two-way analysis of variance (ANOVA and Tukey's test at p < 0.05. All of the alginate impression materials tested exhibited detail reproduction and gypsum compatibility at all times. Hydro Print Premium and Hydrogum 5 showed recovery from deformation, as established by ANSI/ADA specification no. 18, after 5 days of storage. As the storage time increased, the compressive strength values also increased. Considering the properties of compounds' recovery from deformation, compressive strength, and detail reproduction and gypsum compatibility, irreversible hydrocolloids should be poured immediately.

  19. Advanced Caries Microbiota in Teeth with Irreversible Pulpitis.

    Science.gov (United States)

    Rôças, Isabela N; Lima, Kenio C; Assunção, Isauremi V; Gomes, Patrícia N; Bracks, Igor V; Siqueira, José F

    2015-09-01

    Bacterial taxa in the forefront of caries biofilms are candidate pathogens for irreversible pulpitis and are possibly the first ones to invade the pulp and initiate endodontic infection. This study examined the microbiota of the most advanced layers of dentinal caries in teeth with irreversible pulpitis. DNA extracted from samples taken from deep dentinal caries associated with pulp exposures was analyzed for the presence and relative levels of 33 oral bacterial taxa by using reverse-capture checkerboard hybridization assay. Quantification of total bacteria, streptococci, and lactobacilli was also performed by using real-time quantitative polymerase chain reaction. Associations between the target bacterial taxa and clinical signs/symptoms were also evaluated. The most frequently detected taxa in the checkerboard assay were Atopobium genomospecies C1 (53%), Pseudoramibacter alactolyticus (37%), Streptococcus species (33%), Streptococcus mutans (33%), Parvimonas micra (13%), Fusobacterium nucleatum (13%), and Veillonella species (13%). Streptococcus species, Dialister invisus, and P. micra were significantly associated with throbbing pain, S. mutans with pain to percussion, and Lactobacillus with continuous pain (P pulpitis is suspected. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Identification and Characterization of an Irreversible Inhibitor of CDK2.

    Science.gov (United States)

    Anscombe, Elizabeth; Meschini, Elisa; Mora-Vidal, Regina; Martin, Mathew P; Staunton, David; Geitmann, Matthis; Danielson, U Helena; Stanley, Will A; Wang, Lan Z; Reuillon, Tristan; Golding, Bernard T; Cano, Celine; Newell, David R; Noble, Martin E M; Wedge, Stephen R; Endicott, Jane A; Griffin, Roger J

    2015-09-17

    Irreversible inhibitors that modify cysteine or lysine residues within a protein kinase ATP binding site offer, through their distinctive mode of action, an alternative to ATP-competitive agents. 4-((6-(Cyclohexylmethoxy)-9H-purin-2-yl)amino)benzenesulfonamide (NU6102) is a potent and selective ATP-competitive inhibitor of CDK2 in which the sulfonamide moiety is positioned close to a pair of lysine residues. Guided by the CDK2/NU6102 structure, we designed 6-(cyclohexylmethoxy)-N-(4-(vinylsulfonyl)phenyl)-9H-purin-2-amine (NU6300), which binds covalently to CDK2 as shown by a co-complex crystal structure. Acute incubation with NU6300 produced a durable inhibition of Rb phosphorylation in SKUT-1B cells, consistent with it acting as an irreversible CDK2 inhibitor. NU6300 is the first covalent CDK2 inhibitor to be described, and illustrates the potential of vinyl sulfones for the design of more potent and selective compounds. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. New experimental approach to treatment of radiation-induced bone marrow aplasia: ex vivo expansion of hematopoietic cells; Nouvelle approche experimentale du traitement de l`aplasie medullaire radio-induite

    Energy Technology Data Exchange (ETDEWEB)

    Herodin, F.; Mathieu, J.; Drouet, M.; Grenier, N.; Grange, L.; Bourin, P.; Vetillard, J.; Thierry, D.; Mestries, J.C.

    1995-12-31

    The management of bone marrow aplasia secondary to accidental exposure to high doses of ionizing radiations requires new therapeutic protocols in addition to cytokine therapy. The in vitro incubation of hematopoietic stem and progenitor cells from irradiated nonhuman primates with negative and positive regulators of hematopoiesis may lead to helpful products of transfusion. (author).

  2. Advertising and Irreversible Opinion Spreading in Complex Social Networks

    Science.gov (United States)

    Candia, Julián

    Irreversible opinion spreading phenomena are studied on small-world and scale-free networks by means of the magnetic Eden model, a nonequilibrium kinetic model for the growth of binary mixtures in contact with a thermal bath. In this model, the opinion of an individual is affected by those of their acquaintances, but opinion changes (analogous to spin flips in an Ising-like model) are not allowed. We focus on the influence of advertising, which is represented by external magnetic fields. The interplay and competition between temperature and fields lead to order-disorder transitions, which are found to also depend on the link density and the topology of the complex network substrate. The effects of advertising campaigns with variable duration, as well as the best cost-effective strategies to achieve consensus within different scenarios, are also discussed.

  3. Irreversibility of world-sheet renormalization group flow

    International Nuclear Information System (INIS)

    Oliynyk, T.; Suneeta, V.; Woolgar, E.

    2005-01-01

    We demonstrate the irreversibility of a wide class of world-sheet renormalization group (RG) flows to first order in α ' in string theory. Our techniques draw on the mathematics of Ricci flows, adapted to asymptotically flat target manifolds. In the case of somewhere-negative scalar curvature (of the target space), we give a proof by constructing an entropy that increases monotonically along the flow, based on Perelman's Ricci flow entropy. One consequence is the absence of periodic solutions, and we are able to give a second, direct proof of this. If the scalar curvature is everywhere positive, we instead construct a regularized volume to provide an entropy for the flow. Our results are, in a sense, the analogue of Zamolodchikov's c-theorem for world-sheet RG flows on noncompact spacetimes (though our entropy is not the Zamolodchikov C-function)

  4. Irreversible work and inner friction in quantum thermodynamic processes.

    Science.gov (United States)

    Plastina, F; Alecce, A; Apollaro, T J G; Falcone, G; Francica, G; Galve, F; Lo Gullo, N; Zambrini, R

    2014-12-31

    We discuss the thermodynamics of closed quantum systems driven out of equilibrium by a change in a control parameter and undergoing a unitary process. We compare the work actually done on the system with the one that would be performed along ideal adiabatic and isothermal transformations. The comparison with the latter leads to the introduction of irreversible work, while that with the former leads to the introduction of inner friction. We show that these two quantities can be treated on an equal footing, as both can be linked with the heat exchanged in thermalization processes and both can be expressed as relative entropies. Furthermore, we show that a specific fluctuation relation for the entropy production associated with the inner friction exists, which allows the inner friction to be written in terms of its cumulants.

  5. Structural transition models for a class or irreversible aggregates

    International Nuclear Information System (INIS)

    Canessa, E.

    1995-02-01

    A progress report on two recent theoretical approaches proposed to understand the physics of irreversible fractal aggregates showing up a structural transition from a rather dense to a more multibranched growth is presented. In the first approach the transition is understood by solving the Poisson equation on a squared lattice. The second approach is based on the discretization of the Biharmonic equation. Within these models the transition appears when the growth velocity at the fractal surface presents a minimum. The effects of the surrounding medium and geometrical constraints for the seed particles are considered. By using the optical diffraction method, the structural transition is further characterized by a decrease in the fractal dimension for this peculiar class of aggregates. (author). 17 refs, 4 figs

  6. Thermodynamic Optimality criteria for biological systems in linear irreversible thermodynamics

    International Nuclear Information System (INIS)

    Chimal, J C; Sánchez, N; Ramírez, PR

    2017-01-01

    In this paper the methodology of the so-called Linear Irreversible Thermodynamics (LIT) is applied; although traditionally used locally to study general systems in non-equilibrium states in which it is consider both internal and external contributions to the entropy increments in order to analyze the efficiency of two coupled processes with generalized fluxes J 1 , J 2 and their corresponding forces X 1 , X 2 . We extend the former analysis to takes into account two different operating regimes namely: Omega Function and Efficient Power criterion, respectively. Results show analogies in the optimal performance between and we can say that there exist a criteria of optimization which can be used specially for biological systems where a good design of the biological parameters made by nature at maximum efficient power conditions lead to more efficient engines than those at the maximum power conditions or ecological conditions. (paper)

  7. The Social Cost of Stochastic and Irreversible Climate Change

    Science.gov (United States)

    Cai, Y.; Judd, K. L.; Lontzek, T.

    2013-12-01

    Many scientists are worried about climate change triggering abrupt and irreversible events leading to significant and long-lasting damages. For example, a rapid release of methane from permafrost may lead to amplified global warming, and global warming may increase the frequency and severity of heavy rainfall or typhoon, destroying large cities and killing numerous people. Some elements of the climate system which might exhibit such a triggering effect are called tipping elements. There is great uncertainty about the impact of anthropogenic carbon and tipping elements on future economic wellbeing. Any rational policy choice must consider the great uncertainty about the magnitude and timing of global warming's impact on economic productivity. While the likelihood of tipping points may be a function of contemporaneous temperature, their effects are long lasting and might be independent of future temperatures. It is assumed that some of these tipping points might occur even in this century, but also that their duration and post-tipping impact are uncertain. A faithful representation of the possibility of tipping points for the calculation of social cost of carbon would require a fully stochastic formulation of irreversibility, and accounting for the deep layer of uncertainties regarding the duration of the tipping process and also its economic impact. We use DSICE, a DSGE extension of the DICE2007 model of William Nordhaus, which incorporates beliefs about the uncertain economic impact of possible climate tipping events and uses empirically plausible parameterizations of Epstein-Zin preferences to represent attitudes towards risk. We find that the uncertainty associated with anthropogenic climate change imply carbon taxes much higher than implied by deterministic models. This analysis indicates that the absence of uncertainty in DICE2007 and similar IAM models may result in substantial understatement of the potential benefits of policies to reduce GHG emissions.

  8. Constructal theory through thermodynamics of irreversible processes framework

    International Nuclear Information System (INIS)

    Tescari, S.; Mazet, N.; Neveu, P.

    2011-01-01

    Highlights: → Point to area flow problem is solved through Thermodynamics of irreversible processes. → A new optimisation criterion is defined: the exergy or entropy impedance. → Optimisation is performed following two different routes, constructal or global. → Global optimisation is more efficient than constructal optimisation. → Global optimisation enhances the domain of construct benefits. - Abstract: Point to volume flow problem is revisited on a thermodynamics of irreversible processes (TIP) basis. The first step consists in evaluating the local entropy production of the system, and deducing from this expression the phenomenological laws. Then, the total entropy production can be simply evaluated. It is demonstrated that total entropy production can be written in a remarkable form: the product of the so-called entropy impedance with the square of the heat flux. As the heat flux is given, optimisation consists in minimising the entropy impedance. It is also shown that minimising entropy impedance minimises the maximum temperature difference. Applied to the elemental volume, this optimisation process leads to a shape factor close to the one already published. For the first construction, the equivalent system is defined as stated by Prigogine: when subjected to the same constraints, two systems are thermodynamically equivalent if their entropy production is equal. Two optimisation routes are then investigated: a global optimisation where all scales are taken into account and the constructal optimisation where the system is optimised scale by scale. In this second case, results are close to Ghodossi's work. When global optimisation is performed, it is demonstrated that conductive paths have to be spread uniformly in the active material (i.e. the number of elemental volumes must go to infinite). Comparing the two routes, global optimisation leads to better performance than constructal optimisation. Moreover, global optimisation enlarges the domain of

  9. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis

    OpenAIRE

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2013-01-01

    Introduction: Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patie...

  10. ESTIMATION OF IRREVERSIBLE DAMAGEABILITY AT FATIGUE OF CARBON STEEL

    Directory of Open Access Journals (Sweden)

    I. O. Vakulenko

    2014-04-01

    Full Text Available Purpose. Damageability estimation of carbon steel in the conditions of cyclic loading. Methodology. The steel fragments of railway wheel rim and rail head served as material for research with chemical composition 0.65 % С, 0.67 % Mn, 0.3 % Si, 0.027 % P, 0.028 % S и 0.7 % C, 0.82 % Mn, 0.56 % Si, 0.025 % P, 0.029 % S accordingly. The microstructure of tested steels corresponded to the state of metal after a hot plastic deformation. The fatigue research was conducted in the conditions of symmetric bend using the proof-of-concept machine of type «Saturn-10». Full Wohler diagrams and the lines corresponding to forming of sub-and micro cracks were constructed. The distribution analysis of internal stresses in the metal under cyclic loading was carried out using the microhardness tester of PMT-3 type.Findings. On the basis of fatigue curves for high-carbon steels analysis the positions of borders dividing the areas of convertible and irreversible damages were determined. The article shows that with the growth of carbon concentration in the steel at invariability of the structural state an increase of fatigue limit is observed. At the same time the acceleration of processes, which determine transition terms from the stage of forming of submicrocracks to the microcracks occurs. The research of microhardness distribution in the metal after destruction confirmed the nature of carbon amount influence on the carbon steel characteristics. Originality. Regardless on the stages of breakdown site forming the carbon steels behavior at a fatigue is determined by the ration between the processes of strengthening and softening. At a cyclic loading the heterogeneity of internal stresses distribution decreases with the increase of distance from the destruction surface. Analysis of metal internal restructuring processes at fatigue loading made it possible to determine that at the stages prior to incubation period in the metal microvolumes the cells are already

  11. Irreversible block of cardiac mutant Na+ channels by batrachotoxin.

    Science.gov (United States)

    Wang, Sho-Ya; Tikhonov, Denis B; Mitchell, Jane; Zhorov, Boris S; Wang, Ging Kuo

    2007-01-01

    Batrachotoxin (BTX) not only keeps the voltage-gated Na(+) channel open persistently but also reduces its single-channel conductance. Although a BTX receptor has been delimited within the inner cavity of Na(+) channels, how Na(+) ions flow through the BTX-bound permeation pathway remains unclear. In this report we tested a hypothesis that Na(+) ions traverse a narrow gap between bound BTX and residue N927 at D2S6 of cardiac hNa(v)1.5 Na(+) channels. We found that BTX at 5 microM indeed elicited a strong block of hNa(v)1.5-N927K currents (approximately 70%) after 1000 repetitive pulses (+50 mV/20 ms at 2 Hz) without any effects on Na(+) channel gating. Once occurred, this unique use-dependent block of hNa(v)1.5-N927K Na(+) channels recovered little at holding potential (-140 mV), demonstrating that BTX block is irreversible under our experimental conditions. Such an irreversible effect likewise developed in fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels albeit with a faster on-rate; approximately 90% of peak Na(+) currents were abolished by BTX after 200 repetitive pulses (+50 mV/20 ms). This use-dependent block of fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels by BTX was duration dependent. The longer the pulse duration the larger the block developed. Among N927K/W/R/H/D/S/Q/G/E substitutions in fast inactivation-deficient hNa(v)1.5 Na(+) channels, only N927K/R Na(+) currents were highly sensitive to BTX block. We conclude that (a) BTX binds within the inner cavity and partly occludes the permeation pathway and (b) residue hNa(v)1.5-N927 is critical for ion permeation between bound BTX and D2S6, probably because the side-chain of N927 helps coordinate permeating Na(+) ions.

  12. Multiscale Analysis of Time Irreversibility Based on Phase-Space Reconstruction and Horizontal Visibility Graph Approach

    Science.gov (United States)

    Zhang, Yongping; Shang, Pengjian; Xiong, Hui; Xia, Jianan

    Time irreversibility is an important property of nonequilibrium dynamic systems. A visibility graph approach was recently proposed, and this approach is generally effective to measure time irreversibility of time series. However, its result may be unreliable when dealing with high-dimensional systems. In this work, we consider the joint concept of time irreversibility and adopt the phase-space reconstruction technique to improve this visibility graph approach. Compared with the previous approach, the improved approach gives a more accurate estimate for the irreversibility of time series, and is more effective to distinguish irreversible and reversible stochastic processes. We also use this approach to extract the multiscale irreversibility to account for the multiple inherent dynamics of time series. Finally, we apply the approach to detect the multiscale irreversibility of financial time series, and succeed to distinguish the time of financial crisis and the plateau. In addition, Asian stock indexes away from other indexes are clearly visible in higher time scales. Simulations and real data support the effectiveness of the improved approach when detecting time irreversibility.

  13. Fundamental economic irreversibilities influence policies for enhancing international forest phytosanitary security

    Science.gov (United States)

    Thomas P. Holmes; Will Allen; Robert G. Haight; E. Carina H. Keskitalo; Mariella Marzano; Maria Pettersson; Christopher P. Quine; E. R. Langer

    2017-01-01

    National and international efforts to manage forest biosecurity create tension between opposing sources of ecological and economic irreversibility. Phytosanitary policies designed to protect national borders from biological invasions incur sunk costs deriving from economic and political irreversibilities that incentivizes wait-and-see decision-making. However, the...

  14. Phase control of light amplification with dynamically irreversible pathways of population transfer in a Λ system

    International Nuclear Information System (INIS)

    Yuan Shi; Wu Jinhui; Gao Jinyue; Pan Chunliu

    2002-01-01

    We use the relative phase of two coherent fields for the control of light amplification with dynamically irreversible pathways of population transfer in a Λ system. The population inversion and gain with dynamically irreversible pathways of population transfer are shown as the relative phase is varied. We support our results by numerical calculation and analytical explanation

  15. A minimal dissipation type-based classification in irreversible thermodynamics and microeconomics

    Science.gov (United States)

    Tsirlin, A. M.; Kazakov, V.; Kolinko, N. A.

    2003-10-01

    We formulate the problem of finding classes of kinetic dependencies in irreversible thermodynamic and microeconomic systems for which minimal dissipation processes belong to the same type. We show that this problem is an inverse optimal control problem and solve it. The commonality of this problem in irreversible thermodynamics and microeconomics is emphasized.

  16. Fuel starvation. Irreversible degradation mechanisms in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, Carmen M.; Silva, R.A.; Travassos, M.A.; Paiva, T.I.; Fernandes, V.R. [LNEG, National Laboratory for Energy and Geology, Lisboa (Portugal). UPCH Fuel Cells and Hydrogen Unit

    2010-07-01

    PEM fuel cell operates under very aggressive conditions in both anode and cathode. Failure modes and mechanism in PEM fuel cells include those related to thermal, chemical or mechanical issues that may constrain stability, power and lifetime. In this work, the case of fuel starvation is examined. The anode potential may rise to levels compatible with the oxidization of water. If water is not available, oxidation of the carbon support will accelerate catalyst sintering. Diagnostics methods used for in-situ and ex-situ analysis of PEM fuel cells are selected in order to better categorize irreversible changes of the cell. Electrochemical Impedance Spectroscopy (EIS) is found instrumental in the identification of fuel cell flooding conditions and membrane dehydration associated to mass transport limitations / reactant starvation and protonic conductivity decrease, respectively. Furthermore, it indicates that water electrolysis might happen at the anode. Cross sections of the membrane catalyst and gas diffusion layers examined by scanning electron microscopy indicate electrode thickness reduction as a result of reactions taking place during hydrogen starvation. Catalyst particles are found to migrate outwards and located on carbon backings. Membrane degradation in fuel cell environment is analyzed in terms of the mechanism for fluoride release which is considered an early predictor of membrane degradation. (orig.)

  17. Reversibility and irreversibility from an initial value formulation

    Science.gov (United States)

    Muriel, A.

    2013-07-01

    From a time evolution equation for the single particle distribution function derived from the N-particle distribution function (A. Muriel, M. Dresden, Physica D 101 (1997) 297), an exact solution for the 3D Navier-Stokes equation - an old problem - has been found (A. Muriel, Results Phys. 1 (2011) 2). In this Letter, a second exact conclusion from the above-mentioned work is presented. We analyze the time symmetry properties of a formal, exact solution for the single-particle distribution function contracted from the many-body Liouville equation. This analysis must be done because group theoretic results on time reversal symmetry of the full Liouville equation (E.C.G. Sudarshan, N. Mukunda, Classical Mechanics: A Modern Perspective, Wiley, 1974). no longer applies automatically to the single particle distribution function contracted from the formal solution of the N-body Liouville equation. We find the following result: if the initial momentum distribution is even in the momentum, the single particle distribution is reversible. If there is any asymmetry in the initial momentum distribution, no matter how small, the system is irreversible.

  18. Chemotherapy-induced irreversible alopecia in early breast cancer patients.

    Science.gov (United States)

    Kim, Gun Min; Kim, Sanghwa; Park, Hyung Seok; Kim, Jee Ye; Nam, Sanggen; Park, Seho; Kim, Seung Il; Kim, DoYoung; Sohn, Joohyuk

    2017-06-01

    The purpose of this work is to determine the prevalence of chemotherapy-induced irreversible alopecia (CIIA), which is defined as an alopecia that exists at least 6 months after completion of chemotherapy and factors affecting CIIA in early breast cancer patients. We performed a cross-sectional study. We retrospectively identified breast cancer patients who had received AC (Adriamycin, Cyclophosphamide) or AC-T (AC followed by Taxane) as neoadjuvant or adjuvant chemotherapy. We conducted questionnaire survey regarding alopecia and measured hair density using phototrichogram. From February 2015 to May 2015, among 265 patients who responded properly to the questionnaire, the women who answered they had severe alopecia (alopecia > 50% of scalp) were 19 patients (7.2%). AC-only and AC-T treated patients reported severe alopecia in 2.7% and 10.5%, respectively, which were significantly different (p < 0.001). Mean hair density was 75 hair/cm 2 (range 42-112) and 75.2/cm 2 (range 48.3-102) on occipital area and vertex area, respectively. Hair loss was the most frequent in parietal area (42.6%). Half of total patients (46%) and 73% of CIIA patients regarded that their hair became thinner after chemotherapy CONCLUSIONS: We found that significant proportion of early breast cancer patients were suffering from severe CIIA, especially when they had been treated with AC followed by taxane regimen.

  19. Reversibility and irreversibility from an initial value formulation

    International Nuclear Information System (INIS)

    Muriel, A.

    2013-01-01

    From a time evolution equation for the single particle distribution function derived from the N-particle distribution function (A. Muriel, M. Dresden, Physica D 101 (1997) 297), an exact solution for the 3D Navier–Stokes equation – an old problem – has been found (A. Muriel, Results Phys. 1 (2011) 2). In this Letter, a second exact conclusion from the above-mentioned work is presented. We analyze the time symmetry properties of a formal, exact solution for the single-particle distribution function contracted from the many-body Liouville equation. This analysis must be done because group theoretic results on time reversal symmetry of the full Liouville equation (E.C.G. Sudarshan, N. Mukunda, Classical Mechanics: A Modern Perspective, Wiley, 1974). no longer applies automatically to the single particle distribution function contracted from the formal solution of the N-body Liouville equation. We find the following result: if the initial momentum distribution is even in the momentum, the single particle distribution is reversible. If there is any asymmetry in the initial momentum distribution, no matter how small, the system is irreversible.

  20. Road deicing salt irreversibly disrupts osmoregulation of salamander egg clutches

    International Nuclear Information System (INIS)

    Karraker, Nancy E.; Gibbs, James P.

    2011-01-01

    It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations. - Road deicing salts irreversibly disrupts osmoregulation of salamander egg clutches.

  1. Scaling Law for Irreversible Entropy Production in Critical Systems.

    Science.gov (United States)

    Hoang, Danh-Tai; Prasanna Venkatesh, B; Han, Seungju; Jo, Junghyo; Watanabe, Gentaro; Choi, Mahn-Soo

    2016-06-09

    We examine the Jarzynski equality for a quenching process across the critical point of second-order phase transitions, where absolute irreversibility and the effect of finite-sampling of the initial equilibrium distribution arise in a single setup with equal significance. We consider the Ising model as a prototypical example for spontaneous symmetry breaking and take into account the finite sampling issue by introducing a tolerance parameter. The initially ordered spins become disordered by quenching the ferromagnetic coupling constant. For a sudden quench, the deviation from the Jarzynski equality evaluated from the ideal ensemble average could, in principle, depend on the reduced coupling constant ε0 of the initial state and the system size L. We find that, instead of depending on ε0 and L separately, this deviation exhibits a scaling behavior through a universal combination of ε0 and L for a given tolerance parameter, inherited from the critical scaling laws of second-order phase transitions. A similar scaling law can be obtained for the finite-speed quench as well within the Kibble-Zurek mechanism.

  2. Irreversibility and higher-spin conformal field theory

    CERN Document Server

    Anselmi, D

    2000-01-01

    I discuss the idea that quantum irreversibility is a general principle of nature and a related "conformal hypothesis", stating that all fundamental quantum field theories should be renormalization-group (RG) interpolations between ultraviolet and infrared conformal fixed points. In particular, the Newton constant should be viewed as a low-energy effect of the RG scale. This approach leads naturally to consider higher-spin conformal field theories, which are here classified, as candidate high-energy theories. Bosonic conformal tensors have a positive-definite action, equal to the square of a field strength, and a higher-derivative gauge invariance. The central charges c and a are well defined and positive. I calculate their values and study the operator-product structure. Fermionic theories have no gauge invariance and can be coupled to Abelian and non-Abelian gauge fields in a renormalizable way. At the quantum level, they contribute to the one-loop beta function with the same sign as ordinary matter, admit a...

  3. The effects of irreversible electroporation (IRE on nerves.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available BACKGROUND: If a critical nerve is circumferentially involved with tumor, radical surgery intended to cure the cancer must sacrifice the nerve. Loss of critical nerves may lead to serious consequences. In spite of the impressive technical advancements in nerve reconstruction, complete recovery and normalization of nerve function is difficult to achieve. Though irreversible electroporation (IRE might be a promising choice to treat tumors near or involved critical nerve, the pathophysiology of the nerve after IRE treatment has not be clearly defined. METHODS: We applied IRE directly to a rat sciatic nerve to study the long term effects of IRE on the nerve. A sequence of 10 square pulses of 3800 V/cm, each 100 µs long was applied directly to rat sciatic nerves. In each animal of group I (IRE the procedure was applied to produce a treated length of about 10 mm. In each animal of group II (Control the electrodes were only applied directly on the sciatic nerve for the same time. Electrophysiological, histological, and functional studies were performed on immediately after and 3 days, 1 week, 3, 5, 7 and 10 weeks following surgery. FINDINGS: Electrophysiological, histological, and functional results show the nerve treated with IRE can attain full recovery after 7 weeks. CONCLUSION: This finding is indicative of the preservation of nerve involving malignant tumors with respect to the application of IRE pulses to ablate tumors completely. In summary, IRE may be a promising treatment tool for any tumor involving nerves.

  4. Irreversible electroporation of human primary uveal melanoma in enucleated eyes.

    Directory of Open Access Journals (Sweden)

    Yossi Mandel

    Full Text Available Uveal melanoma (UM is the most common primary intraocular tumor in adults and is characterized by high rates of metastatic disease. Although brachytherapy is the most common globe-sparing treatment option for small- and medium-sized tumors, the treatment is associated with severe adverse reactions and does not lead to increased survival rates as compared to enucleation. The use of irreversible electroporation (IRE for tumor ablation has potential advantages in the treatment of tumors in complex organs such as the eye. Following previous theoretical work, herein we evaluate the use of IRE for uveal tumor ablation in human ex vivo eye model. Enucleated eyes of patients with uveal melanoma were treated with short electric pulses (50-100 µs, 1000-2000 V/cm using a customized electrode design. Tumor bioimpedance was measured before and after treatment and was followed by histopathological evaluation. We found that IRE caused tumor ablation characterized by cell membrane disruption while sparing the non-cellular sclera. Membrane disruption and loss of cellular capacitance were also associated with significant reduction in total tumor impedance and loss of impedance frequency dependence. The effect was more pronounced near the pulsing electrodes and was dependent on time from treatment to fixation. Future studies should further evaluate the potential of IRE as an alternative method of uveal melanoma treatment.

  5. Irreversible electroporation of human primary uveal melanoma in enucleated eyes.

    Science.gov (United States)

    Mandel, Yossi; Laufer, Shlomi; Belkin, Michael; Rubinsky, Boris; Pe'er, Jacob; Frenkel, Shahar

    2013-01-01

    Uveal melanoma (UM) is the most common primary intraocular tumor in adults and is characterized by high rates of metastatic disease. Although brachytherapy is the most common globe-sparing treatment option for small- and medium-sized tumors, the treatment is associated with severe adverse reactions and does not lead to increased survival rates as compared to enucleation. The use of irreversible electroporation (IRE) for tumor ablation has potential advantages in the treatment of tumors in complex organs such as the eye. Following previous theoretical work, herein we evaluate the use of IRE for uveal tumor ablation in human ex vivo eye model. Enucleated eyes of patients with uveal melanoma were treated with short electric pulses (50-100 µs, 1000-2000 V/cm) using a customized electrode design. Tumor bioimpedance was measured before and after treatment and was followed by histopathological evaluation. We found that IRE caused tumor ablation characterized by cell membrane disruption while sparing the non-cellular sclera. Membrane disruption and loss of cellular capacitance were also associated with significant reduction in total tumor impedance and loss of impedance frequency dependence. The effect was more pronounced near the pulsing electrodes and was dependent on time from treatment to fixation. Future studies should further evaluate the potential of IRE as an alternative method of uveal melanoma treatment.

  6. Irreversible chemical steps control intersubunit dynamics during translation

    Science.gov (United States)

    Marshall, R. Andrew; Dorywalska, Magdalena; Puglisi, Joseph D.

    2008-01-01

    The ribosome, a two-subunit macromolecular machine, deciphers the genetic code and catalyzes peptide bond formation. Dynamic rotational movement between ribosomal subunits is likely required for efficient and accurate protein synthesis, but direct observation of intersubunit dynamics has been obscured by the repetitive, multistep nature of translation. Here, we report a collection of single-molecule fluorescence resonance energy transfer assays that reveal a ribosomal intersubunit conformational cycle in real time during initiation and the first round of elongation. After subunit joining and delivery of correct aminoacyl-tRNA to the ribosome, peptide bond formation results in a rapid conformational change, consistent with the counterclockwise rotation of the 30S subunit with respect to the 50S subunit implied by prior structural and biochemical studies. Subsequent binding of elongation factor G and GTP hydrolysis results in a clockwise rotation of the 30S subunit relative to the 50S subunit, preparing the ribosome for the next round of tRNA selection and peptide bond formation. The ribosome thus harnesses the free energy of irreversible peptidyl transfer and GTP hydrolysis to surmount activation barriers to large-scale conformational changes during translation. Intersubunit rotation is likely a requirement for the concerted movement of tRNA and mRNA substrates during translocation. PMID:18824686

  7. General performance characteristics of an irreversible ferromagnetic Stirling refrigeration cycle

    International Nuclear Information System (INIS)

    Lin, G.; Tegus, O.; Zhang, L.; Brueck, E.

    2004-01-01

    A new magnetic-refrigeration-cycle model using ferromagnetic materials as a cyclic working substance is set up, in which finite-rate heat transfer, heat leak and regeneration time are taken into account. On the basis of the thermodynamic properties of a ferromagnetic material, the general performance characteristics of the ferromagnetic Stirling refrigeration cycle are investigated and the effects of some key irreversibilities on the performance of the cycle are revealed. By using the optimal-control theory, the optimal relation between the coefficient of performance and the cooling rate is derived and some important performance bounds, e.g., the maximum cooling rate, the maximum coefficient of performance, are determined. Moreover, the optimal operating regions for cooling rate, coefficient of performance and the optimal operating temperatures of a cyclic working substance in the two heat-transfer processes are obtained. Furthermore, the influences of magnetization and magnetic field on the performance characteristics of the cycle are discussed. The results obtained here have general significance and can be deduced to the related ones of the Stirling refrigeration cycle using paramagnetic salt as a cyclic working substance

  8. Ecological optimization and parametric study of irreversible Stirling and Ericsson heat pumps

    International Nuclear Information System (INIS)

    Tyagi, S.K.; Kaushik, S.C.; Salohtra, R.

    2002-01-01

    This communication presents the ecological optimization and parametric study of irreversible Stirling and Ericsson heat pump cycles, in which the external irreversibility is due to finite temperature difference between working fluid and external reservoirs while the internal irreversibilities are due to regenerative heat loss and other entropy generations within the cycle. The ecological function is defined as the heating load minus the irreversibility (power loss) which is ambient temperature times the entropy generation. The ecological function is optimized with respect to working fluid temperatures, and the expressions for various parameters at the optimal operating condition are obtained. The effects of different operating parameters on the performance of these cycles have been studied. It is found that the effect of internal irreversibility parameter is more pronounced than the other parameters on the performance of these cycles. (author)

  9. Macroscopic irreversibility and microscopic paradox: A Constructal law analysis of atoms as open systems

    Science.gov (United States)

    Lucia, Umberto

    2016-10-01

    The relation between macroscopic irreversibility and microscopic reversibility is a present unsolved problem. Constructal law is introduced to develop analytically the Einstein’s, Schrödinger’s, and Gibbs’ considerations on the interaction between particles and thermal radiation (photons). The result leads to consider the atoms and molecules as open systems in continuous interaction with flows of photons from their surroundings. The consequent result is that, in any atomic transition, the energy related to the microscopic irreversibility is negligible, while when a great number of atoms (of the order of Avogadro’s number) is considered, this energy related to irreversibility becomes so large that its order of magnitude must be taken into account. Consequently, macroscopic irreversibility results related to microscopic irreversibility by flows of photons and amount of atoms involved in the processes.

  10. A model of irreversible jam formation in dense traffic

    Science.gov (United States)

    Brankov, J. G.; Bunzarova, N. Zh.; Pesheva, N. C.; Priezzhev, V. B.

    2018-03-01

    We study an one-dimensional stochastic model of vehicular traffic on open segments of a single-lane road of finite size L. The vehicles obey a stochastic discrete-time dynamics which is a limiting case of the generalized Totally Asymmetric Simple Exclusion Process. This dynamics has been previously used by Bunzarova and Pesheva (2017) for an one-dimensional model of irreversible aggregation. The model was shown to have three stationary phases: a many-particle one, MP, a phase with completely filled configuration, CF, and a boundary perturbed MP+CF phase, depending on the values of the particle injection (α), ejection (β) and hopping (p) probabilities. Here we extend the results for the stationary properties of the MP+CF phase, by deriving exact expressions for the local density at the first site of the chain and the probability P(1) of a completely jammed configuration. The unusual phase transition, characterized by jumps in both the bulk density and the current (in the thermodynamic limit), as α crosses the boundary α = p from the MP to the CF phase, is explained by the finite-size behavior of P(1). By using a random walk theory, we find that, when α approaches from below the boundary α = p, three different regimes appear, as the size L → ∞: (i) the lifetime of the gap between the rightmost clusters is of the order O(L) in the MP phase; (ii) small jams, separated by gaps with lifetime O(1) , exist in the MP+CF phase close to the left chain boundary; and (iii) when β = p, the jams are divided by gaps with lifetime of the order O(L 1 / 2) . These results are supported by extensive Monte Carlo calculations.

  11. Irreversible collective migration of cyanobacteria in eutrophic conditions.

    Directory of Open Access Journals (Sweden)

    Julien Dervaux

    Full Text Available In response to natural or anthropocentric pollutions coupled to global climate changes, microorganisms from aquatic environments can suddenly accumulate on water surface. These dense suspensions, known as blooms, are harmful to ecosystems and significantly degrade the quality of water resources. In order to determine the physico-chemical parameters involved in their formation and quantitatively predict their appearance, we successfully reproduced irreversible cyanobacterial blooms in vitro. By combining chemical, biochemical and hydrodynamic evidences, we identify a mechanism, unrelated to the presence of internal gas vesicles, allowing the sudden collective upward migration in test tubes of several cyanobacterial strains (Microcystis aeruginosa PCC 7005, Microcystis aeruginosa PCC 7806 and Synechocystis sp. PCC 6803. The final state consists in a foamy layer of biomass at the air-liquid interface, in which micro-organisms remain alive for weeks, the medium lying below being almost completely depleted of cyanobacteria. These "laboratory blooms" start with the aggregation of cells at high ionic force in cyanobacterial strains that produce anionic extracellular polymeric substances (EPS. Under appropriate conditions of nutrients and light intensity, the high photosynthetic activity within cell clusters leads the dissolved oxygen (DO to supersaturate and to nucleate into bubbles. Trapped within the EPS, these bubbles grow until their buoyancy pulls the biomass towards the free surface. By investigating a wide range of spatially homogeneous environmental conditions (illumination, salinity, cell and nutrient concentration we identify species-dependent thresholds and timescales for bloom formation. We conclude on the relevance of such results for cyanobacterial bloom formation in the environment and we propose an efficient method for biomass harvesting in bioreactors.

  12. Ictal time-irreversible intracranial EEG signals as markers of the epileptogenic zone.

    Science.gov (United States)

    Schindler, Kaspar; Rummel, Christian; Andrzejak, Ralph G; Goodfellow, Marc; Zubler, Frédéric; Abela, Eugenio; Wiest, Roland; Pollo, Claudio; Steimer, Andreas; Gast, Heidemarie

    2016-09-01

    To show that time-irreversible EEG signals recorded with intracranial electrodes during seizures can serve as markers of the epileptogenic zone. We use the recently developed method of mapping time series into directed horizontal graphs (dHVG). Each node of the dHVG represents a time point in the original intracranial EEG (iEEG) signal. Statistically significant differences between the distributions of the nodes' number of input and output connections are used to detect time-irreversible iEEG signals. In 31 of 32 seizure recordings we found time-irreversible iEEG signals. The maximally time-irreversible signals always occurred during seizures, with highest probability in the middle of the first seizure half. These signals spanned a large range of frequencies and amplitudes but were all characterized by saw-tooth like shaped components. Brain regions removed from patients who became post-surgically seizure-free generated significantly larger time-irreversibilities than regions removed from patients who still had seizures after surgery. Our results corroborate that ictal time-irreversible iEEG signals can indeed serve as markers of the epileptogenic zone and can be efficiently detected and quantified in a time-resolved manner by dHVG based methods. Ictal time-irreversible EEG signals can help to improve pre-surgical evaluation in patients suffering from pharmaco-resistant epilepsies. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  13. Procesos de magnetización reversible-irreversible y propiedades de remanencia de ferrita de cobalto coprecipitada

    Directory of Open Access Journals (Sweden)

    Medina-Boudri, A.

    2001-10-01

    Full Text Available Cobalt ferrite was obtained by coprecipitation of iron (II sulphate and cobalt (II sulphate in acetone medium. Using the moving Preisach model, the reversible (Mrev and irreversible (Mirr components of the magnetization were separated. The parameter η given by η= (dMrev / dMirrHi and the moving Preisach parameter km , were evaluated according to the relation η= kmχrev in order to investigate the behavior of Mrev. It was found that η is not proportional to the reversible susceptibility, therefore km is a function of the internal field. Isothermal remanent magnetization (IRM and DC demagnetization (DCD curves were measured . From these data the δm curve and the Henkel plot were obtained showing that all the points remain under the Wohlfath line indicating that the local disorder dominates (demagnetizing-like effect over the mean-field effect. The switching field distribution curves were obtained by differentiation of the IRM and DCD curves. The peak values of these switching field distributions differ by a factor of 2.7.

    Se obtuvo ferrita de cobalto por coprecipitación de sulfatos de hierro y cobalto en acetona. Usando el modelo móvil de Preisach se separaron las componentes reversible (Mrev e irreversible (Mirr de la magnetización. El parámetro η definido como η= (dMrev / dMirrHi y el parámetro móvil de Preisach km , se evaluaron mediante la relación η= kmχrev para investigar el comportamiento de Mrev Se encontró que η no es proporcional a la susceptibilidad reversible, por lo tanto, km es una función del campo interno. Se midieron las curvas de magnetización isotérmica remanente (MIR y de desmagnetización (DCD. A partir de los datos MIR y DCD se construyó la curva δm y el gráfico de Henkel, el cual se encuentra por debajo de la línea de Wohlfarth indicando que domina el desorden local (efecto del tipo desmagnetizante sobre el efecto de campo medio. Diferenciando las curvas de MIR y DCD se obtuvieron las curvas

  14. Performance of an irreversible quantum Ericsson cooler at low temperature limit

    International Nuclear Information System (INIS)

    Wu Feng; Chen Lingen; Wu Shuang; Sun Fengrui

    2006-01-01

    The purpose of this paper is to investigate the effect of quantum properties of the working medium on the performance of an irreversible quantum Ericsson cooler with spin-1/2. The cooler is studied with the losses of heat resistance, heat leakage and internal irreversibility. The optimal relationship between the dimensionless cooling load R * versus the coefficient of performance ε for the irreversible quantum Ericsson cooler is derived. In particular, the performance characteristics of the cooler at the low temperature limit are discussed

  15. A Fingerprint Encryption Scheme Based on Irreversible Function and Secure Authentication

    Directory of Open Access Journals (Sweden)

    Yijun Yang

    2015-01-01

    Full Text Available A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users’ fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.

  16. Optimization of the performance characteristics in an irreversible magnetic Brayton refrigeration cycle

    International Nuclear Information System (INIS)

    Wang Hao; Liu Sanqiu

    2008-01-01

    An irreversible cycle model of magnetic Brayton refrigerators is established, in which the thermal resistance and irreversibility in the two adiabatic processes are taken into account. Expressions for several important performance parameters, such as the coefficient of performance, cooling rate and power input are derived. Moreover, the optimal performance parameters are obtained at the maximum coefficient of performance. The optimization region (or criteria) for an irreversible magnetic Brayton refrigerator is obtained. The results obtained here have general significance and will be helpful to understand deeply the performance of a magnetic Brayton refrigeration cycle

  17. A fingerprint encryption scheme based on irreversible function and secure authentication.

    Science.gov (United States)

    Yang, Yijun; Yu, Jianping; Zhang, Peng; Wang, Shulan

    2015-01-01

    A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users' fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm) to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.

  18. Ecological optimization of an irreversible quantum Carnot heat engine with spin-1/2 systems

    International Nuclear Information System (INIS)

    Liu Xiaowei; Chen Lingen; Wu Feng; Sun Fengrui

    2010-01-01

    A model of a quantum heat engine with heat resistance, internal irreversibility and heat leakage and many non-interacting spin-1/2 systems is established in this paper. The quantum heat engine cycle is composed of two isothermal processes and two irreversible adiabatic processes and is referred to as a spin quantum Carnot heat engine. Based on the quantum master equation and the semi-group approach, equations of some important performance parameters, such as power output, efficiency, entropy generation rate and ecological function (a criterion representing the optimal compromise between exergy output rate and exergy loss rate), for the irreversible spin quantum Carnot heat engine are derived. The optimal ecological performance of the heat engine in the classical limit is analyzed with numerical examples. The effects of internal irreversibility and heat leakage on ecological performance are discussed in detail.

  19. Evaluation of properties of irreversible hydrocolloid impression materials mixed with disinfectant liquids

    Directory of Open Access Journals (Sweden)

    Arul Amalan

    2013-01-01

    Conclusion: Chlorhexidine solution can be used to mix irreversible hydrocolloid impression materials in regular dental practice as it did not significantly alter the properties. This may ensure effective disinfection of impressions.

  20. Treatise on irreversible and statistical thermodynamics an introduction to nonclassical thermodynamics

    CERN Document Server

    Yourgrau, Wolfgang; Raw, Gough

    2002-01-01

    Extensively revised edition of a much-respected work examines thermodynamics of irreversible processes, general principles of statistical thermodynamics, assemblies of noninteracting structureless particles, and statistical theory. 1966 edition.

  1. [Complex method of treating chronic, irreversible peripheral facial palsy particularly considering rehabilitation postoperatively].

    Science.gov (United States)

    Kukwa, A; Ignaczak, A; Pietniczka-Załeska, M; Matusiak, S

    1992-01-01

    Authors described the scheme of the functional reconstruction of the face in patients with protracted, irreversible, peripheral facial palsy and the subsequent rehabilitation. A new, own method of treatment has been introduced considering anatomical and functional relations.

  2. Sample size effect on the determination of the irreversibility line of high-Tc superconductors

    International Nuclear Information System (INIS)

    Li, Q.; Suenaga, M.; Li, Q.; Freltoft, T.

    1994-01-01

    The irreversibility lines of a high-J c superconducting Bi 2 Sr 2 Ca 2 Cu 3 O x /Ag tape were systematically measured upon a sequence of subdivisions of the sample. The irreversibility field H r (T) (parallel to the c axis) was found to change approximately as L 0.13 , where L is the effective dimension of the superconducting tape. Furthermore, it was found that the irreversibility line for a grain-aligned Bi 2 Sr 2 Ca 2 Cu 3 O x specimen can be approximately reproduced by the extrapolation of this relation down to a grain size of a few tens of micrometers. The observed size effect could significantly obscure the real physical meaning of the irreversibility lines. In addition, this finding surprisingly indicated that the Bi 2 Sr 2 Ca 2 Cu 2 O x /Ag tape and grain-aligned specimen may have similar flux line pinning strength

  3. Irreversibility analysis for gravity driven non-Newtonian liquid film along an inclined isothermal plate

    International Nuclear Information System (INIS)

    Makinde, O.D.

    2005-10-01

    In this paper, the first and second law of thermodynamics are employed in order to study the inherent irreversibility for a gravity driven non-Newtonian Ostwald-de Waele power law liquid film along an inclined isothermal plate. Based on some simplified assumptions, the governing equations are obtained and solved analytically. Expressions for fluid velocity, temperature, volumetric entropy generation numbers, irreversibility distribution ratio and the Bejan number are also determined. (author)

  4. Performance Optimization of Generalized Irreversible Refrigerator Based on a New Ecological Criterion

    OpenAIRE

    Xu, Jie; Pang, Liping; Wang, Jun

    2013-01-01

    On the basis of the exergy analysis, a performance optimization is carried out for a generalized irreversible refrigerator model, which takes into account the heat resistance, heat leakage and internal irreversibility losses. A new ecological criterion, named coefficient of performance of exergy (COPE), defined as the dimensionless ratio of the exergy output rate to the exergy loss rate, is proposed as an objective function in this paper. The optimal performance factors which maximize the eco...

  5. Irreversible Electroporation of a Hepatocellular Carcinoma Lesion Adjacent to a Transjugular Intrahepatic Portosystemic Shunt Stent Graft

    Energy Technology Data Exchange (ETDEWEB)

    Niessen, Christoph; Jung, Ernst Michael; Wohlgemuth, Walter A. [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany); Trabold, Benedikt [Department of Anaesthesia, University Medical Center Regensburg, Regensburg D-93053 (Germany); Haimerl, Michael; Schreyer, Andreas; Stroszczynski, Christian; Wiggermann, Philipp [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany)

    2013-07-01

    We report in a 65-year-old man hepatocellular carcinoma adjacent to a transjugular intrahepatic portosystemic shunt stent-graft which was successfully treated with irreversible electroporation (IRE). IRE is a new non-thermal tissue ablation technique which uses electrical pulses to induce cell necrosis by irreversible membrane poration. IRE proved to be more advantageous in the ablation of perivascular tumor with little injury to the surrounding structures.

  6. Characterization of irreversible physio-mechanical processes in stretched fetal membranes.

    Science.gov (United States)

    Marom, Yulia; Goldman, Shlomit; Shalev, Eliezer; Shilo, Doron

    2016-01-01

    We perform bulge tests on live fetal membrane (FM) tissues that simulate the mechanical conditions prior to contractions. Experimental results reveal an irreversible mechanical behavior that appears during loading and is significantly different than the mechanical behavior that appears during unloading or in subsequent loading cycles. The irreversible behavior results in a residual strain that does not recover upon unloading and remains the same for at least 1h after the FM is unloaded. Surprisingly, the irreversible behavior demonstrates a linear stress-strain relation. We introduce a new model for the mechanical response of collagen tissues, which accounts for the irreversible deformation and provides predictions in agreement with our experimental results. The basic assumption of the model is that the constitutive stress-strain relationship of individual elements that compose the collagen fibers has a plateau segment during which an irreversible transformation/deformation occurs. Fittings of calculated and measured stress-strain curves reveal a well-defined single-value property of collagenous tissues, which is related to the threshold strain εth for irreversible transformation. Further discussion of several physio-mechanical processes that can induce irreversible behavior indicate that the most probable process, which is in agreement with our results for εth, is a phase transformation of collagen molecules from an α-helix to a β-sheet structure. A phase transformation is a manifestation of a significant change in the molecular structure of the collagen tissues that can alter connections with surrounding molecules and may lead to critical biological changes, e.g., an initiation of labor. This study is driven by the hypothesis that pre-contraction mechanical stretch of the fetal membrane (FM) can lead to a change in the microstructure of the FM, which in turn induces a critical biological (hormonal) change that leads to the initiation of labor. We present

  7. Non-input analysis for incomplete trapping irreversible tracer with PET.

    Science.gov (United States)

    Ohya, Tomoyuki; Kikuchi, Tatsuya; Fukumura, Toshimitsu; Zhang, Ming-Rong; Irie, Toshiaki

    2013-07-01

    When using metabolic trapping type tracers, the tracers are not always trapped in the target tissue; i.e., some are completely trapped in the target, but others can be eliminated from the target tissue at a measurable rate. The tracers that can be eliminated are termed 'incomplete trapping irreversible tracers'. These incomplete trapping irreversible tracers may be clinically useful when the tracer β-value, the ratio of the tracer (metabolite) elimination rate to the tracer efflux rate, is under approximately 0.1. In this study, we propose a non-input analysis for incomplete trapping irreversible tracers based on the shape analysis (Shape), a non-input analysis used for irreversible tracers. A Monte Carlo simulation study based on experimental monkey data with two actual PET tracers (a complete trapping irreversible tracer [(11)C]MP4A and an incomplete trapping irreversible tracer [(18)F]FEP-4MA) was performed to examine the effects of the environmental error and the tracer elimination rate on the estimation of the k3-parameter (corresponds to metabolic rate) using Shape (original) and modified Shape (M-Shape) analysis. The simulation results were also compared with the experimental results obtained with the two PET tracers. When the tracer β-value was over 0.03, the M-Shape method was superior to the Shape method for the estimation of the k3-parameter. The simulation results were also in reasonable agreement with the experimental ones. M-Shape can be used as the non-input analysis of incomplete trapping irreversible tracers for PET study. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Fluctuation theorems in feedback-controlled open quantum systems: Quantum coherence and absolute irreversibility

    Science.gov (United States)

    Murashita, Yûto; Gong, Zongping; Ashida, Yuto; Ueda, Masahito

    2017-10-01

    The thermodynamics of quantum coherence has attracted growing attention recently, where the thermodynamic advantage of quantum superposition is characterized in terms of quantum thermodynamics. We investigate the thermodynamic effects of quantum coherent driving in the context of the fluctuation theorem. We adopt a quantum-trajectory approach to investigate open quantum systems under feedback control. In these systems, the measurement backaction in the forward process plays a key role, and therefore the corresponding time-reversed quantum measurement and postselection must be considered in the backward process, in sharp contrast to the classical case. The state reduction associated with quantum measurement, in general, creates a zero-probability region in the space of quantum trajectories of the forward process, which causes singularly strong irreversibility with divergent entropy production (i.e., absolute irreversibility) and hence makes the ordinary fluctuation theorem break down. In the classical case, the error-free measurement ordinarily leads to absolute irreversibility, because the measurement restricts classical paths to the region compatible with the measurement outcome. In contrast, in open quantum systems, absolute irreversibility is suppressed even in the presence of the projective measurement due to those quantum rare events that go through the classically forbidden region with the aid of quantum coherent driving. This suppression of absolute irreversibility exemplifies the thermodynamic advantage of quantum coherent driving. Absolute irreversibility is shown to emerge in the absence of coherent driving after the measurement, especially in systems under time-delayed feedback control. We show that absolute irreversibility is mitigated by increasing the duration of quantum coherent driving or decreasing the delay time of feedback control.

  9. The use of TiO2 nanoparticles to reduce refrigerator ir-reversibility

    International Nuclear Information System (INIS)

    Padmanabhan, Venkataramana Murthy V.; Palanisamy, Senthilkumar

    2012-01-01

    Highlights: ► COP of hydrocarbons mixture VCRSs increases less when compared to R134a. ► Compressor ir-reversibility of VCRSs decreases by 33% (R134a), 14% (R436A and R436B). ► Total ir-reversibility of selected VCRSs decreases. ► Exergy efficiency of R134a is exceptionally low at lower reference temperature. ► Exergy efficiency of selected VCRSs increases. - Abstract: The ir-reversibility at the process of a vapour-compression refrigeration system (VCRS) with nanoparticles in the working fluid was investigated experimentally. Mineral oil (MO) with 0.1 g L −1 TiO 2 nanoparticles mixture were used as the lubricant instead of Polyol-ester (POE) oil in the R134a, R436A (R290/R600a-56/44-wt.%) and R436B (R290/R600a-52/48-wt.%)VCRSs. The VCRS ir-reversibility at the process with the nanoparticles was investigated using second law of thermodynamics. The results indicate that R134a, R436A and R436B and MO with TiO 2 nanoparticles work normally and safely in the VCRS. The VCRSs total ir-reversibility (529, 588 and 570 W) at different process was better than the R134a, R436A and R436B and POE oil system (777, 697 and 683 W). The same tests with Al 2 O 3 nanoparticles showed that the different nanoparticles properties have little effect on the VCRS ir-reversibility. Thus, TiO 2 nanoparticles can be used in VCRS with reciprocating compressor to considerably reduce ir-reversibility at the process.

  10. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis.

    Science.gov (United States)

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2014-01-01

    Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patient related factors, safety and organizational consideration as parts of health technology assessment (HTA) of the new VPT/CEM biotechnology when compared with RCT. Patient related factors were assessed by looking at short- and long-term clinical success; safety related factors were evaluated by a specialist committee and discussion board involved in formulating healthcare policies. Organizational evaluation was performed and the social implications were assessed by estimating the costs, availability, accessibility and acceptability. The impact of VPT/CEM biotechnology was assessed by investigating the incidence of irreversible pulpitis and the effect of this treatment on reducing the burden of disease. VPT/CEM biotechnology was deemed feasible and acceptable like RCT; however, it was more successful, accessible, affordable, available and also safer than RCT. When considering socioeconomic implications on oral health status and oral health-related quality of life of VPT/CEM, the novel biotechnology can be more effective and more efficient than RCT in mature permanent molars with irreversible pulpitis.

  11. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis

    Science.gov (United States)

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2014-01-01

    Introduction: Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patient related factors, safety and organizational consideration as parts of health technology assessment (HTA) of the new VPT/CEM biotechnology when compared with RCT. Materials and Methods: Patient related factors were assessed by looking at short- and long-term clinical success; safety related factors were evaluated by a specialist committee and discussion board involved in formulating healthcare policies. Organizational evaluation was performed and the social implications were assessed by estimating the costs, availability, accessibility and acceptability. The impact of VPT/CEM biotechnology was assessed by investigating the incidence of irreversible pulpitis and the effect of this treatment on reducing the burden of disease. Results: VPT/CEM biotechnology was deemed feasible and acceptable like RCT; however, it was more successful, accessible, affordable, available and also safer than RCT. Conclusion: When considering socioeconomic implications on oral health status and oral health-related quality of life of VPT/CEM, the novel biotechnology can be more effective and more efficient than RCT in mature permanent molars with irreversible pulpitis. PMID:24396372

  12. Substance P and CGRP expression in dental pulps with irreversible pulpitis.

    Science.gov (United States)

    Sattari, Mandana; Mozayeni, Mohammad Ali; Matloob, Arash; Mozayeni, Maryam; Javaheri, Homan H

    2010-08-01

    The purpose of this study was to compare substance P (SP) and calcitonin gene-related peptide (CGRP) expression in pulp tissue with clinically diagnosed symptomatic and asymptomatic irreversible pulpitis. Healthy pulps acted as controls. Five normal pulps and 40 with irreversible pulpitis (20 symptomatic and 20 asymptomatic) were obtained from 45 different patients. SP and CGRP expression was determined by competition binding assays using enzyme immunoassay. anova and Mann-Whitney tests were used to ascertain if there were statistically significant differences between the groups. The results showed that neuropeptides were found in all pulp samples. The highest and the lowest expressions for SP and CGRP were found in symptomatic irreversible pulpitis and healthy pulps groups, respectively. The differences between healthy pulps and the groups of pulps having irreversible pulpitis were significant (P pulpitis groups (P pulpitis groups were not significant. This study demonstrated that the expression of CGRP and SP is significantly higher in pulps with irreversible pulpitis compared with healthy pulps.

  13. Performance Optimization of Generalized Irreversible Refrigerator Based on a New Ecological Criterion

    Directory of Open Access Journals (Sweden)

    Jie Xu

    2013-11-01

    Full Text Available On the basis of the exergy analysis, a performance optimization is carried out for a generalized irreversible refrigerator model, which takes into account the heat resistance, heat leakage and internal irreversibility losses. A new ecological criterion, named coefficient of performance of exergy (COPE, defined as the dimensionless ratio of the exergy output rate to the exergy loss rate, is proposed as an objective function in this paper. The optimal performance factors which maximize the ecological objective function have been discussed. Numerical examples are given to explain the influences of heat leakage and internal irreversibility on the generalized and optimal performances. This new ecological criterion may be beneficial for determining the reasonable design of refrigerators.

  14. Effect of regeneration on the thermo-ecological performance analysis and optimization of irreversible air refrigerators

    Science.gov (United States)

    Ust, Yasin

    2010-04-01

    A thermo-ecological performance analysis of an irreversible regenerative air refrigerator cycle exchanging heat with thermal reservoirs is presented. In the analysis, the external irreversibility effects due to heat transfer across finite temperature differences and the heat leak loss between the external heat reservoirs while the internal irreversibilities are due to the non-isentropic compression and expansion processes and the regenerative loss are taken into account. The effects of regeneration and heat sources temperature ratio are given special emphasis and investigated in detail. A comparative performance analysis considering the objective functions of an ecological coefficient of performance, exergetic efficiency and coefficient of performance is also carried out. The maximum of the objective functions and the corresponding optimal conditions have been derived analytically. The obtained results may provide a general theoretical tool for the thermo-ecological design of regenerative air refrigerators.

  15. Statistical Irreversible Thermodynamics in the Framework of Zubarev's Nonequilibrium Statistical Operator Method

    Science.gov (United States)

    Luzzi, R.; Vasconcellos, A. R.; Ramos, J. G.; Rodrigues, C. G.

    2018-01-01

    We describe the formalism of statistical irreversible thermodynamics constructed based on Zubarev's nonequilibrium statistical operator (NSO) method, which is a powerful and universal tool for investigating the most varied physical phenomena. We present brief overviews of the statistical ensemble formalism and statistical irreversible thermodynamics. The first can be constructed either based on a heuristic approach or in the framework of information theory in the Jeffreys-Jaynes scheme of scientific inference; Zubarev and his school used both approaches in formulating the NSO method. We describe the main characteristics of statistical irreversible thermodynamics and discuss some particular considerations of several authors. We briefly describe how Rosenfeld, Bohr, and Prigogine proposed to derive a thermodynamic uncertainty principle.

  16. Long buccal nerve block injection pain in patients with irreversible pulpitis.

    Science.gov (United States)

    Drum, Melissa; Reader, Al; Beck, Mike

    2011-07-01

    The purpose of this study was to determine the pain associated with needle insertion (with or without topical anesthetic) and solution deposition for the long buccal nerve block injection in patients with irreversible pulpitis. Initial pain and any differences by age and gender were also studied. One hundred twelve emergency patients with irreversible pulpitis received long buccal nerve block injections using 2% lidocaine with 1:100,000 epinephrine. The patients recorded pain of needle insertion and solution deposition on a Heft-Parker visual analog scale (VAS). Moderate-to-severe pain occurred from 41% to 46% of the time with the long buccal nerve block. The use of topical anesthetic did not statistically decrease the pain of needle insertion. In conclusion, 41% to 46% of patients presenting with irreversible pulpitis have the potential for moderate-to-severe pain with the long buccal nerve block. Copyright © 2011 Mosby, Inc. All rights reserved.

  17. FINITE TIME THERMODYNAMIC MODELING AND ANALYSIS FOR AN IRREVERSIBLE ATKINSON CYCLE

    Directory of Open Access Journals (Sweden)

    Yanlin Ge

    2010-01-01

    Full Text Available Performance of an air-standard Atkinson cycle is analyzed by using finite-time thermodynamics. The irreversible cycle model which is more close to practice is founded. In this model, the non-linear relation between the specific heats of working fluid and its temperature, the friction loss computed according to the mean velocity of the piston, the internal irreversibility described by using the compression and expansion efficiencies, and heat transfer loss are considered. The relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, as well as the optimal relation between power output and the efficiency of the cycle are derived by detailed numerical examples. Moreover, the effects of internal irreversibility, heat transfer loss and friction loss on the cycle performance are analyzed. The results obtained in this paper may provide guidelines for the design of practical internal combustion engines.

  18. Peptide Drug Release Behavior from Biodegradable Temperature-Responsive Injectable Hydrogels Exhibiting Irreversible Gelation

    Directory of Open Access Journals (Sweden)

    Kazuyuki Takata

    2017-10-01

    Full Text Available We investigated the release behavior of glucagon-like peptide-1 (GLP-1 from a biodegradable injectable polymer (IP hydrogel. This hydrogel shows temperature-responsive irreversible gelation due to the covalent bond formation through a thiol-ene reaction. In vitro sustained release of GLP-1 from an irreversible IP formulation (F(P1/D+PA40 was observed compared with a reversible (physical gelation IP formulation (F(P1. Moreover, pharmaceutically active levels of GLP-1 were maintained in blood after subcutaneous injection of the irreversible IP formulation into rats. This system should be useful for the minimally invasive sustained drug release of peptide drugs and other water-soluble bioactive reagents.

  19. Canonical formalism, fundamental equation, and generalized thermomechanics for irreversible fluids with heat transfer

    International Nuclear Information System (INIS)

    Sieniutycz, S.; Berry, R.S.

    1993-01-01

    A Lagrangian with dissipative (e.g., Onsager's) potentials is constructed for the field description of irreversible heat-conducting fluids, off local equilibrium. Extremum conditions of action yield Clebsch representations of temperature, chemical potential, velocities, and generalized momenta, including a thermal momentum introduced recently [R. L. Selinger and F. R. S. Whitham, Proc. R. Soc. London, Ser. A 302, 1 (1968); S. Sieniutycz and R. S. Berry, Phys. Rev. A 40, 348 (1989)]. The basic question asked is ''To what extent may irreversibility, represented by a given form of the entropy source, influence the analytical form of the conservation laws for the energy and momentum?'' Noether's energy for a fluid with heat flow is obtained, which leads to a fundamental equation and extended Hamiltonian dynamics obeying the second law of thermodynamics. While in the case of the Onsager potentials this energy coincides numerically with the classical energy E, it contains an extra term (vanishing along the path) still contributing to an irreversible evolution. Components of the energy-momentum tensor preserve all terms regarded standardly as ''irreversible'' (heat, tangential stresses, etc.) generalized to the case when thermodynamics includes the state gradients and the so-called thermal phase, which we introduce here. This variable, the Lagrange multiplier of the entropy generation balance, is crucial for consistent treatment of irreversible processes via an action formalism. We conclude with the hypothesis that embedding the first and second laws in the context of the extremal behavior of action under irreversible conditions may imply accretion of an additional term to the classical energy

  20. Inequalities for trace anomalies, length of the RG flow, distance between the fixed points and irreversibility

    International Nuclear Information System (INIS)

    Anselmi, Damiano

    2004-01-01

    I discuss several issues about the irreversibility of the RG flow and the trace anomalies c, a and a'. First I argue that in quantum field theory: (i) the scheme-invariant area Δ a' of the graph of the effective beta function between the fixed points defines the length of the RG flow; (ii) the minimum of Δ a' in the space of flows connecting the same UV and IR fixed points defines the (oriented) distance between the fixed points and (iii) in even dimensions, the distance between the fixed points is equal to Δ a = a UV - a IR . In even dimensions, these statements imply the inequalities 0 ≤ Δ a ≤ Δ a' and therefore the irreversibility of the RG flow. Another consequence is the inequality a ≤ c for free scalars and fermions (but not vectors), which can be checked explicitly. Secondly, I elaborate a more general axiomatic set-up where irreversibility is defined as the statement that there exist no pairs of non-trivial flows connecting interchanged UV and IR fixed points. The axioms, based on the notions of length of the flow, oriented distance between the fixed points and certain 'oriented-triangle inequalities', imply the irreversibility of the RG flow without a global a function. I conjecture that the RG flow is also irreversible in odd dimensions (without a global a function). In support of this, I check the axioms of irreversibility in a class of d = 3 theories where the RG flow is integrable at each order of the large N expansion

  1. Irreversible and reversible components in the genesis of hypertension by sodium chloride (salt).

    Science.gov (United States)

    Tekol, Yalcin

    2008-01-01

    Despite the abundant studies and overwhelming evidences demonstrating the essential role of salt (sodium chloride) for developing "essential" hypertension (EH), the controversies about salt-hypertension (HT) relations are still continuing. One of important mistakes in this topic is assuming that the HT-producing effect of salt is reversible. The present paper explains the complex nature of salt-HT relations. The deduction was made basing on the studies which investigate the relations between salt and HT. Animal experiments show that HT-producing effect of salt contains irreversible and reversible components. The existence of irreversible component manifests itself in this way: the blood pressure (BP) does not recede to the natural values despite removing of salt exposure. The proportion of BP decreasing after salt exposure termination belongs to the reversible component. Available evidences indicate that the irreversible component is developed in utero, during suckling and, generally, in prepubertal period secondary to salt exposure, however, if the salt exposure extends over more than one period, the HT may be intensified. The consequences of salt exposure during early life of human beings have not been investigated as detailed as in experimental animals, however, there are some clinical trials and epidemiological observations indicating that, similar to experimental animals, irreversible and reversible components are also developed in man during the genesis of HT. By the introduction of irreversible and reversible components notion, some obscured items on salt-HT relations can be clarified. For example, some intervention studies could not find dramatic relations between salt and HT, because these interventions modify only the reversible component, but irreversible component remains unchanged. As a result, salt exposure is detrimental for each period of life. For eradication of HT, it is prerequisite to prevent all individuals (especially pregnant or lactating

  2. Antibacterial efficacy and effect of chlorhexidine mixed with irreversible hydrocolloid for dental impressions: a randomized controlled trial.

    Science.gov (United States)

    Cubas, Glória; Valentini, Fernanda; Camacho, Guilherme Brião; Leite, Fábio; Cenci, Maximiliano Sérgio; Pereira-Cenci, Tatiana

    2014-01-01

    This study aimed to evaluate whether chlorhexidine mixed with irreversible hydrocolloid powder decreases microbial contamination during impression taking without affecting the resulting casts. Twenty volunteers were randomly divided into two groups (n = 10) according to the liquid used for impression taking in conjunction with irreversible hydrocolloid: 0.12% chlorhexidine or water. Surface roughness and dimensional stability of the casts were evaluated. Chlorhexidine mixed with irreversible hydrocolloid decreased the percentage of microorganisms when compared with water (P impression quality.

  3. The universal power and efficiency characteristics for irreversible reciprocating heat engine cycles

    CERN Document Server

    Qin Xiao Yong; Sun Feng Rui; Wu Chih

    2003-01-01

    The performance of irreversible reciprocating heat engine cycles with heat transfer loss and friction-like term loss is analysed using finite-time thermodynamics. The universal relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, and the optimal relation between power output and the efficiency of the cycles are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of cycle processes on the performance of the cycle using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson and Brayton cycles.

  4. Effects of irreversibility and economics on the performance of a heat engine

    International Nuclear Information System (INIS)

    Ibrahim, O.M.; Klein, S.A.; Mitchell, J.W.

    1992-01-01

    In this paper, optimization of the power output of an internally irreversible heat engine is considered for finite capacitance rates of the external fluid streams. The method of Lagrange multipliers is used to solve for working fluid temperatures which yield maximum power. Analytical expressions for the maximum power and the cycle efficiency at miximum power are obtained. The effects of irreversibility and economics on the performance of a heat engine are investigated. A relationship between the maximum power point and economically optimum design is identified. It is demonstrated that, with certain reasonable economic assumptions, the maximum power point of a heat engine corresponds to a point of minimum life-cycle costs

  5. Irreversible Change of the Pore Structure of ZIF-8 in Carbon Dioxide Capture with Water Coexistence

    DEFF Research Database (Denmark)

    Liu, Huang; Guo, Ping; Regueira Muñiz, Teresa

    2016-01-01

    showed an irreversible change of its framework, which occurs during the CO2 capture process. It was found that there is an irreversible chemical reaction among ZIF-8, water, and CO2, which creates both zinc carbonate (or zinc carbonate hydroxides) and single 2-methylimidazole crystals, and therefore...... the pore structure of ZIF-8 collapses. It is suggested therefore that care must be taken when using ZIF-8 or products containing ZIF-8 for gas capture, gas separation, or other applications where both water and acid gases coexist....

  6. Irreversible magnetization process and switching mechanism in L10 FePt thin films

    Directory of Open Access Journals (Sweden)

    A. Lisfi

    2017-05-01

    Full Text Available The irreversible characteristics of the magnetization and the switching mechanism have been investigated in granular FePt films with L10 phase prepared by sputtering on a polymer substrate. The films display an extremely large magnetic anisotropy with a random distribution of the magnetization easy axis. The magnetic instabilities and the irreversible magnetization are found to be controlled by domain wall, which is responsible for the magnetization reversal. Through remanence curves and ΔM plot, the nature of magnetic interactions was revealed to be positive exchange coupling.

  7. Antibacterial efficacy and effect of Morinda citrifolia L. mixed with irreversible hydrocolloid for dental impressions: A randomized controlled trial.

    Science.gov (United States)

    Ahmed, A Shafath; Charles, P David; Cholan, R; Russia, M; Surya, R; Jailance, L

    2015-08-01

    This study aimed to evaluate whether the extract of Morinda citrifolia L. mixed with irreversible hydrocolloid powder decreases microbial contamination during impression making without affecting the resulting casts. Twenty volunteers were randomly divided into two groups (n = 10). Group A 30 ml extract of M. citrifolia L diluted in 30 ml of water was mixed to make the impression with irreversible hydrocolloid material. Group B 30 ml deionized water was mixed with irreversible hydrocolloid material to make the impressions following which the surface roughness and dimensional stability of casts were evaluated. Extract of M. citrifolia L. mixed with irreversible hydrocolloid decreased the percentage of microorganisms when compared with water (P impression quality.

  8. Unreal perpetual motion machine, Rydberg constant and Carnot non-unitary efficiency as a consequence of the atomic irreversibility

    Science.gov (United States)

    Lucia, Umberto

    2018-02-01

    A perpetual motion machine is a completely ideal engine which cannot be realized. Carnot introduced the concept of the ideal engine which operates on a completely reversible cycle, without any dissipation, but with an upper limit in it. So, even in ideal condition without any dissipation, there is something that prevents the conversion of all the energy absorbed by an ideal reservoir into work. But what is the cause of irreversibility? Here we highlight the atomic nature of this irreversibility, proving that it is no more than the continuous interaction of the atoms with the surrounding field. The macroscopic irreversibility is the consequence of the microscopic irreversibility.

  9. Celulitis por citomegalovirus

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  10. Embolia pulmonar por polimetilmetacrilato

    OpenAIRE

    Héctor Gómez Santa María; Mauro García Aurelio; Yanina Castillo Costa; Víctor Mauro; Carlos Barrero

    2009-01-01

    Los primeros registros de embolia pulmonar por polimetilmetacrilato se publicaron recientemente (2003) y desde entonces se describieron no más de 15 casos. Se presenta el caso de un paciente joven a quien dos meses antes de la consulta se le había efectuado una vertebroplastia percutánea con polimetilmetacrilato. Por síntomas pleuríticos se le realizó una radiografía de tórax, que evidenció múltiples imágenes radioopacas en ambos campos pulmonares. La embolia pulmonar por polimetilmetacrilato...

  11. Performance characteristics and parametric optimization of an irreversible magnetic Ericsson heat-pump

    International Nuclear Information System (INIS)

    Wei Fang; Lin Guoxing; Chen Jincan; Brueck, Ekkes

    2011-01-01

    Taking into account the finite-rate heat transfer in the heat-transfer processes, heat leak between the two external heat reservoirs, regenerative loss, regeneration time, and internal irreversibility due to dissipation of the cycle working substance, an irreversible magnetic Ericsson heat-pump cycle is presented. On the basis of the thermodynamic properties of magnetic materials, the performance characteristics of the irreversible magnetic Ericsson heat-pump are investigated and the relationship between the optimal heating load and the coefficient of performance (COP) is derived. Moreover, the maximum heating load and the corresponding COP as well as the maximum COP and the corresponding heating load are obtained. Furthermore, the other optimal performance characteristics are discussed in detail. The results obtained here may provide some new information for the optimal parameter design and the development of real magnetic Ericsson heat-pumps. -- Research Highlights: →The effects of multi-irreversibilities on the performance of a magnetic heat-pump are revealed. →Mathematical expressions of the heating load and the COP are derived and the optimal performance and operating parameters are analyzed and discussed. →Several important performance bounds are determined.

  12. Ecological optimization and performance study of irreversible Stirling and Ericsson heat engines

    Science.gov (United States)

    Tyagi, S. K.; Kaushik, S. C.; Salhotra, R.

    2002-10-01

    The concept of finite time thermodynamics is used to determine the ecological function of irreversible Stirling and Ericsson heat engine cycles. The ecological function is defined as the power output minus power loss (irreversibility), which is the ambient temperature times, the entropy generation rate. The ecological function is maximized with respect to cycle temperature ratio and the expressions for the corresponding power output and thermal efficiency are derived at the optimal operating conditions. The effect of different operating parameters, the effectiveness on the hot, cold and the regenerative side heat exchangers, the cycle temperature ratio, heat capacitance ratio and the internal irreversibility parameter on the maximum ecological function are studied. It is found that the effect of regenerator effectiveness is more than the hot and cold side heat exchangers and the effect of the effectiveness on cold side heat exchanger is more than the effectiveness on the hot side heat exchanger on the maximum ecological function. It is also found that the effect of internal irreversibility parameter is more than the other parameters not only on the maximum ecological function but also on the corresponding power output and the thermal efficiency.

  13. Ecological optimization and performance study of irreversible Stirling and Ericsson heat engines

    International Nuclear Information System (INIS)

    Tyagi, S K; Kaushik, S C; Salhotra, R

    2002-01-01

    The concept of finite time thermodynamics is used to determine the ecological function of irreversible Stirling and Ericsson heat engine cycles. The ecological function is defined as the power output minus power loss (irreversibility), which is the ambient temperature times, the entropy generation rate. The ecological function is maximized with respect to cycle temperature ratio and the expressions for the corresponding power output and thermal efficiency are derived at the optimal operating conditions. The effect of different operating parameters, the effectiveness on the hot, cold and the regenerative side heat exchangers, the cycle temperature ratio, heat capacitance ratio and the internal irreversibility parameter on the maximum ecological function are studied. It is found that the effect of regenerator effectiveness is more than the hot and cold side heat exchangers and the effect of the effectiveness on cold side heat exchanger is more than the effectiveness on the hot side heat exchanger on the maximum ecological function. It is also found that the effect of internal irreversibility parameter is more than the other parameters not only on the maximum ecological function but also on the corresponding power output and the thermal efficiency

  14. How to account for irreversibility in integrated assessment of climate change?

    International Nuclear Information System (INIS)

    Ha Duong, M.

    1998-04-01

    How to account for irreversibility in integrated assessment of climate change? This Ph. D. thesis in Economics balances discounting, technical progress and the inertia of existing capital stock against uncertainty and the inertia of socio-economic systems to examine the issue of near term limitations of greenhouse gases emissions. After a general overview in chapter 2, and a more historical presentation of the debates in chapter 3, chapter 4 proceeds to review a large number of integrated assessment models. Chapter 5 introduces a Model on the Dynamics of Inertia and Adaptability of energy systems: DIAM, used to discuss how much previous studies might have overestimated the long term costs of CO 2 limitations and underestimated adjustment costs. It shows that, given a target date for atmospheric CO 2 concentration stabilisation, a higher inertia implies a lower optimal concentration trajectory. In a sequential decision framework, chapter 6 shows that current uncertainties about which CO 2 concentration ceiling would not present dangerous interference with the climate system justifies precautionary action. Finally, chapter 7 uses the irreversibility effect theory to define formally situations of decision under controversy and compare the irreversibility of CO 2 accumulation with the irreversibility of investments needed to moderate it. An option value for greenhouse gases emissions limitations is computed. (author)

  15. Irreversible thermodynamics of dark energy on the entropy-corrected apparent horizon

    Energy Technology Data Exchange (ETDEWEB)

    Karami, K; Sahraei, N [Department of Physics, University of Kurdistan, Pasdaran Street, Sanandaj (Iran, Islamic Republic of); Jamil, M, E-mail: KKarami@uok.ac.i, E-mail: mjamil@camp.nust.edu.p [Center for Advanced Mathematics and Physics (CAMP), National University of Sciences and Technology (NUST), Islamabad (Pakistan)

    2010-10-15

    We study the irreversible (non-equilibrium) thermodynamics of the Friedmann-Robertson-Walker (FRW) universe containing only dark energy. Using the modified entropy-area relation that is motivated by loop quantum gravity, we calculate the entropy-corrected form of the apparent horizon of the FRW universe.

  16. Pulpitis irreversible como forma de presentación de un odontoma

    OpenAIRE

    Berástegui, Esther; Buenechea Imaz, Ramón

    1997-01-01

    Se presenta un caso de odontoma compuesto que provocó pulpitis irreversible en el incisivo central superior derecho (1,1) en una joven de 20 años. El tratamiento fue la biopulpectomía total y extirpación quirúrgica del tumor.

  17. Unifying principles of irreversibility minimization for efficiency maximization in steady-flow chemically-reactive engines

    International Nuclear Information System (INIS)

    Ramakrishnan, Sankaran; Edwards, Christopher F.

    2014-01-01

    Systems research has led to the conception and development of various steady-flow, chemically-reactive, engine cycles for stationary power generation and propulsion. However, the question that remains unanswered is: What is the maximum-efficiency steady-flow chemically-reactive engine architecture permitted by physics? On the one hand the search for higher-efficiency cycles continues, often involving newer processes and devices (fuel cells, carbon separation, etc.); on the other hand the design parameters for existing cycles are continually optimized in response to improvements in device engineering. In this paper we establish that any variation in engine architecture—parametric change or process-sequence change—contributes to an efficiency increase via one of only two possible ways to minimize total irreversibility. These two principles help us unify our understanding from a large number of parametric analyses and cycle-optimization studies for any steady-flow chemically-reactive engine, and set a framework to systematically identify maximum-efficiency engine architectures. - Highlights: • A unified thermodynamic model to study chemically-reactive engine architectures is developed. • All parametric analyses of efficiency are unified by two irreversibility-minimization principles. • Variations in internal energy transfers yield a net work increase that is greater than engine irreversibility reduced. • Variations in external energy transfers yield a net work increase that is lesser than engine irreversibility reduced

  18. Irreversibility and multiplicity: two criteria for the disposal of nuclear wastes

    International Nuclear Information System (INIS)

    Rochlin, G.

    1976-01-01

    Two criteria are suggested for comparing waste management methods: technical irreversibility and site multiplicity. These criteria can be used to reduce future risk in the face of inherent uncertainty and to provide for safe disposal without requiring guaranteed future ability to recognize, detect or repair areas of failure

  19. Herbivore regulation and irreversible vegetation change in semi-arid grazing systems

    NARCIS (Netherlands)

    Van de Koppel, J.; Rietkerk, M.

    2000-01-01

    Models made to explain sudden and irreversible vegetation shifts in semi-arid grasslands typically assume that herbivore density is independent of the state of the vegetation, e.g., under the control of humans. We relax this assumption and investigate the mathematical implications of

  20. A comparison of the anesthetic efficacy of articaine and lidocaine in patients with irreversible pulpitis.

    Science.gov (United States)

    Tortamano, Isabel Peixoto; Siviero, Marcelo; Costa, Carina Gisele; Buscariolo, Inês Aparecida; Armonia, Paschoal Laércio

    2009-02-01

    The purpose of the present study was to compare the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine with that of 2% lidocaine with 1:100,000 epinephrine during pulpectomy in patients with irreversible pulpitis in mandibular posterior teeth. Forty volunteers, patients with irreversible pulpitis admitted to the Emergency Center of the School of Dentistry at the University of São Paulo, randomly received a conventional inferior alveolar nerve block containing 3.6 mL of either 4% articaine with 1:100,000 epinephrine or 2% lidocaine with 1:100,000 epinephrine. During the subsequent pulpectomy, we recorded the patients' subjective assessments of lip anesthesia, the absence/presence of pulpal anesthesia through electric pulp stimulation, and the absence/presence of pain through a verbal analogue scale. All tested patients reported lip anesthesia after the application of either inferior alveolar nerve block. Regarding pulpal anesthesia success as measured with the pulp tester, the lidocaine solution had a higher success rate (70%) than the articaine solution (65%). For patients reporting none or mild pain during pulpectomy, the success rate of the articaine solution (65%) was higher than that of the lidocaine solution (45%). Yet, none of the observed differences between articaine and lidocaine were statistically significant. Apparently, therefore, both local anesthetic solutions had similar effects on the patients with irreversible pulpitis in mandibular posterior teeth. Neither of the solutions, however, resulted in an effective pain control during irreversible pulpitis treatments.

  1. Modelling plastic deformation of metals over a wide range of strain rates using irreversible thermodynamics

    NARCIS (Netherlands)

    Huang, M.; Rivera-Diaz-del-Castillo, P.E.J.; Bouaziz, O.; Van der Zwaag, S.

    2009-01-01

    Based on the theory of irreversible thermodynamics, the present work proposes a dislocation-based model to describe the plastic deformation of FCC metals over wide ranges of strain rates. The stress-strain behaviour and the evolution of the average dislocation density are derived. It is found that

  2. Revisiting the Glansdorff–Prigogine criterion for stability within irreversible thermodynamics

    Czech Academy of Sciences Publication Activity Database

    Maes, C.; Netočný, Karel

    2015-01-01

    Roč. 159, č. 6 (2015), s. 1286-1299 ISSN 0022-4715 R&D Projects: GA ČR GAP204/12/0897 Institutional support: RVO:68378271 Keywords : irreversible processes * thermodynamic stability * excess entropy production * nonequilibrium free energy * Clausius heat theorem Subject RIV: BE - Theoretical Physics Impact factor: 1.537, year: 2015

  3. Thermodynamics of Irreversible Processes. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    Science.gov (United States)

    Levin, Michael; Gallucci, V. F.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module describes the application of irreversible thermodynamics to biology. It begins with…

  4. Gel-free proteomic methodologies to study reversible cysteine oxidation and irreversible protein carbonyl formation.

    Science.gov (United States)

    Boronat, S; García-Santamarina, S; Hidalgo, E

    2015-05-01

    Oxidative modifications in proteins have been traditionally considered as hallmarks of damage by oxidative stress and aging. However, oxidants can generate a huge variety of reversible and irreversible modifications in amino acid side chains as well as in the protein backbones, and these post-translational modifications can contribute to the activation of signal transduction pathways, and also mediate the toxicity of oxidants. Among the reversible modifications, the most relevant ones are those arising from cysteine oxidation. Thus, formation of sulfenic acid or disulfide bonds is known to occur in many enzymes as part of their catalytic cycles, and it also participates in the activation of signaling cascades. Furthermore, these reversible modifications have been usually attributed with a protective role, since they may prevent the formation of irreversible damage by scavenging reactive oxygen species. Among irreversible modifications, protein carbonyl formation has been linked to damage and death, since it cannot be repaired and can lead to protein loss-of-function and to the formation of protein aggregates. This review is aimed at researchers interested on the biological consequences of oxidative stress, both at the level of signaling and toxicity. Here we are providing a concise overview on current mass-spectrometry-based methodologies to detect reversible cysteine oxidation and irreversible protein carbonyl formation in proteomes. We do not pretend to impose any of the different methodologies, but rather to provide an objective catwalk on published gel-free approaches to detect those two types of modifications, from a biologist's point of view.

  5. Wall heat flux influence on the thermodynamic optimisation of irreversibilities of a circulating fluidised bed combustor

    CSIR Research Space (South Africa)

    Baloyi, J

    2016-07-01

    Full Text Available In the study the comparison of irreversibilities was done when the wall condition of the combustor was changed from adiabatic to negative heat flux, for incoming air temperature of 400 K. The reactant mixture of solid pitch pine wood fuel and air...

  6. Site-specific properties and irreversible vegetation changes in semi-arid grazing systems

    NARCIS (Netherlands)

    Rietkerk, M; vandenBosch, F; vandeKoppel, J

    1997-01-01

    There is an urgent need to develop a mechanistic understanding of how site-specific properties can lead to irreversible vegetation changes. We show, by means of a bifurcation analysis of two mathematical models, how site-specific properties determine the resilience of vegetation changes in semi-arid

  7. Site-specific properties and irreversible vegetation changes in semi-arid grazing systems

    NARCIS (Netherlands)

    Rietkerk, M.G.; Bosch, F. van den; Koppel, J. van de

    1997-01-01

    There is an urgent need to develop a mechanistic understanding of how site-specific properties can lead to irreversible vegetation changes. We show, by means of a bifurcation analysis of two mathematica1 models, how site-specific properties determine the resilience of vegetation changes in

  8. Thermal Energy during Irreversible Electroporation and the Influence of Different Ablation Parameters

    NARCIS (Netherlands)

    van den Bos, Willemien; Scheffer, Hester J.; Vogel, Jantien A.; Wagstaff, Peter G. K.; de Bruin, Daniel M.; de Jong, Marcus C.; van Gemert, Martin J. C.; de La Rosette, Jean J. M. C. H.; Meijerink, Martijn R.; Klaessens, John H.; Verdaasdonk, Rudolf M.

    2016-01-01

    Irreversible electroporation (IRE) uses high-voltage electric fields to achieve cell death. Although the mechanism of IRE is mainly designated as nonthermal, development of secondary Joule heating is inevitable. The study purpose was to gain understanding of temperature development and distribution

  9. Embolia pulmonar por polimetilmetacrilato

    Directory of Open Access Journals (Sweden)

    Héctor Gómez Santa María

    2009-01-01

    Full Text Available Los primeros registros de embolia pulmonar por polimetilmetacrilato se publicaron recientemente (2003 y desde entonces se describieron no más de 15 casos. Se presenta el caso de un paciente joven a quien dos meses antes de la consulta se le había efectuado una vertebroplastia percutánea con polimetilmetacrilato. Por síntomas pleuríticos se le realizó una radiografía de tórax, que evidenció múltiples imágenes radioopacas en ambos campos pulmonares. La embolia pulmonar por polimetilmetacrilato es una complicación muy poco frecuente de ese procedimiento y un diagnóstico diferencial para tener en cuenta en pacientes con el antecedente y que consulten por dolor precordial o disnea.REV ARGENT CARDIOL 2009;77:129-130.

  10. Quantum thermodynamics: Microscopic foundations of entropy and of entropy generation by irreversibility

    Directory of Open Access Journals (Sweden)

    Beretta, Gian Paolo

    2008-02-01

    Full Text Available What is the physical significance of entropy? What is the physical origin of irreversibility? Do entropy and irreversibility exist only for complex and macroscopic systems? Most physicists still accept and teach that the rationalization of these fundamental questions is given by Statistical Mechanics. Indeed, for everyday laboratory physics, the mathematical formalism of Statistical Mechanics (canonical and grand-canonical, Boltzmann, Bose-Einstein and Fermi-Dirac distributions allows a successful description of the thermodynamic equilibrium properties of matter, including entropy values. However, as already recognized by Schrodinger in 1936, Statistical Mechanics is impaired by conceptual ambiguities and logical inconsistencies, both in its explanation of the meaning of entropy and in its implications on the concept of state of a system. An alternative theory has been developed by Gyftopoulos, Hatsopoulos and the present author to eliminate these stumbling conceptual blocks while maintaining the mathematical formalism so successful in applications. To resolve both the problem of the meaning of entropy and that of the origin of irreversibility we have built entropy and irreversibility into the laws of microscopic physics. The result is a theory, that we call Quantum Thermodynamics, that has all the necessary features to combine Mechanics and Thermodynamics uniting all the successful results of both theories, eliminating the logical inconsistencies of Statistical Mechanics and the paradoxes on irreversibility, and providing an entirely new perspective on the microscopic origin of irreversibility, nonlinearity (therefore including chaotic behavior and maximal-entropy-generation nonequilibrium dynamics. In this paper we discuss the background and formalism of Quantum Thermodynamics including its nonlinear equation of motion and the main general results. Our objective is to show in a not-too-technical manner that this theory provides indeed a

  11. Very Long Segment Congenital Thoracoabdominal Aortic Coarctation (Diffuse Aortic Dysplasia) with Infrarenal Aortobi-Iliac and Cavobi-Iliac Aplasia in a 30-Year-Old Patient.

    Science.gov (United States)

    Mamopoulos, Apostolos; Luther, Bernd

    2015-10-01

    Congenital dysplastic aortic syndromes range from coarctation at the aortic isthmus to more extended aortic disease (midaortic syndrome). The latter is usually restricted to dysplastic aortic segments of up to 15 cm. Long segment dysplasia of the entire abdominal or thoracic aorta is extremely rare. This case of a 30-year-old patient with a very long segment congenital thoracoabdominal aortic coarctation and infrarenal aortobi-iliac and cavobi-iliac aplasia represents to our knowledge the most extended congenital vascular malformation in a surviving adult patient. The developed extensive collateral pathways ensured the survival of the patient, so that the main clinical manifestation was a refractory hypertension. Because of the extent of the disease, open surgery represented the only viable option. Interestingly, after 30 years of uncontrollable hypertension, the patient's blood pressure promptly responded to surgical treatment. A concomitant infrarenal aplasia of both the aorta and cava vein is also very unusual and points to a major developmental deficit during vascular embryogenesis. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Neumonitis por Hipersensibilidad asociado al cuidado de aves.

    Directory of Open Access Journals (Sweden)

    Ana María González Zúñiga

    2015-01-01

    Full Text Available La neumonitis por hipersensibilidad asociada al cuidado de las aves, es uno de los tipos más frecuentes de neumonitis que se presentan. Aunque no se tienen datos epidemiológicos claros sobre su prevalencia, en los hospitales llegan casos de este tipo de neumonitis. No es una patología muy común, sin embargo, mucha de la población se encuentra expuesta a las aves y consecuentemente a los antígenos que causan la enfermedad. Su diagnóstico temprano puede significar para el paciente daños reversibles al dejar de exponerse al antígeno, contrario sino se realiza un diagnóstico temprano, puede generar un daño pulmonar irreversible. En este artículo, presentaremos un caso clínico de neumonitis por hipersensibilidad al cuidado de aves y hablaremos de la enfermedad.

  13. Pinning and irreversibility in superconducting bulk MgB{sub 2} with added nanodiamonds

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Anurag [Superconductivity and Cryogenics Division, National Physical Laboratory (CSIR), New Delhi-110012 (India); Narlikar, A V, E-mail: anurag@mail.nplindia.ernet.i [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore-452017, MP (India)

    2009-12-15

    Resistance, R(T), and magnetization, M(B), studies on superconducting bulk MgB{sub 2} samples containing nanodiamonds (ND) as additives (wt% of ND: x = 0%, 1%, 3%, 5%, 7% and 10%) were recently published in two articles (Vajpayee et al 2007 Supercond. Sci. Technol. 20 S155, Vajpayee et al 2008 J. Appl. Phys. 103 07C708). The main observations reported were significant improvements in the critical current density J{sub c}(B), irreversibility line B{sub irr}(T) and upper critical field B{sub c2}(T) with ND addition. However, a closer look shows that as regards the potential of this technologically important material at higher magnetic fields and temperatures, there is still a lot of room for improvement. With that in mind we revisit the R(T) and M(B) data and analyze them, in the present work. We show that, despite ND addition, J{sub c} depends strongly on B in the high field region and tends to vanish at irreversibility lines that lie deep, i.e. at around 0.3 B{sub c2}(T), in the B-T phase diagram. The irreversibility lines, determined by R(T){yields}0 in the presence of B, are found to lie at around 0.5 B{sub c2}(T) in the phase diagram. These results for pinning and irreversibility lines are discussed in the light of various models such as those of surface sheath superconductivity, magnetically introduced percolation in polycrystalline MgB{sub 2}, thermally assisted flux motion (TAFM) and a modified flux line shear mechanism. Our analysis hints at TAFM and weak pinning channels with distributed superconducting properties percolating in our samples determining the irreversibility and pinning properties.

  14. Multi-objective optimization of an irreversible Stirling cryogenic refrigerator cycle

    International Nuclear Information System (INIS)

    Ahmadi, Mohammad H.; Ahmadi, Mohammad Ali; Mohammadi, Amir H.; Feidt, Michel; Pourkiaei, Seyed Mohsen

    2014-01-01

    Highlights: • A parametric investigation of irreversible Stirling cryogenic refrigerator cycles is presented. • Both internal and external irreversibilities are included in this study, moreover, heat capacities of external reservoirs are involved. • Multi-objective evolutionary algorithm based on NSGA-II approach is utilized. • Three robust decision making approaches are utilized to determine final optimum solution. - Abstract: The main aim of this research article is a parametric demonstration of irreversible Stirling cryogenic refrigerator cycles that includes irreversibilities such as external and internal irreversibilities. In addition, through this study, finite heat capacities of external reservoirs are considered accordingly. To reach the addressed goal of this research, three objective functions that include the input power of the Stirling refrigerator, the coefficient of performance (COP) and cooling load (R L ) have been involved in optimization process simultaneously. The first aforementioned objective function has to minimize; the rest objective functions, on the other hand, have to maximize in parallel optimization process. Developed multi objective evolutionary approaches (MOEAs) based on NSGA-II algorithm is implemented throughout this work. Moreover, cold-side’s effectiveness of the heat exchanger, hot-side’s effectiveness of the heat exchanger, heat source’s heat capacitance rate, heat sink’s capacitance rate, temperature ratio ((T h )/(T c ) ), temperature of cold side are assigned as decision variables for decision making procedure. To gain a robust decision, different decision making approaches that include TOPSIS, LINMAP and fuzzy Bellman–Zadeh are used. Pareto optimal frontier was determined precisely and then three final outputs have been gained by means of the mentioned decision making approaches

  15. PANCITOPENIA EN UN CANINO OCASIONADA POR LA ADMINISTRACIÓN DE ESTROGENOS PARA EVITAR UNA PREÑEZ NO DESEADA

    Directory of Open Access Journals (Sweden)

    Diego Echeverri.

    2007-12-01

    Full Text Available Objetivo. Presentar el caso clínico de una paciente canina pancitopenica debido al uso indebido de estrógenos como método anticonceptivo. Materiales y métodos. Paciente canina de raza Poodle de 8 años, la cual fue llevada a consulta por presentar decaimiento, inapetencia, hemorragias petequiales e hipema. Resultado. Una vez realizada la anamnesis, el examen físico y los exámenes paraclínicos así como la evolución del cuadro clínico se demostró la intoxicación estrogénica exógena como diagnóstico definitivo. Conclusiones. El uso de estrógenos como método para la terminación de preñez en perras no está recomendado o considerado ético para muchos autores o asociaciones veterinarias por varias razones como: una dosis de estrógenos aparentemente efectiva no se ha establecido, por lo que su administración puede resultar en enfermedad uterina; dosis de estrógenos aparentemente seguras fueron determinadas como inseguras, y dosis aparentemente efectivas produjeron enfermedad uterina. La aplasia medular es un resultado común de la intoxicación estrogénica y esta puede conducir incluso a la muerte del paciente.

  16. The analysis of irreversibility, uncertainty and dynamic technical inefficiency on the investment decision in the Spanish olive sector

    NARCIS (Netherlands)

    Lambarraa, Fatima; Stefanou, Spiro; Gil, José M.

    2016-01-01

    This study addresses irreversible investment decision-making in the context of uncertainty when allowing for inefficiency to be transmitted over time. Both irreversibility and persistence in technical inefficiency can lead to sluggish adjustment of quasi-fixed factors of production. The context

  17. Labile phytochrome and photoperiodic flower induction in Pharbitis nil Chois. The irreversible phytochrome hypothesis

    Directory of Open Access Journals (Sweden)

    Mariusz Cymerski

    2014-01-01

    Full Text Available Seedlings of Pharbitis nil cultivated under non-inductive conditions of white light were subjected to generative induction applying one 16-hour-long period of inductive night. During the eighth hour the night was interrupted with 1 min of red light pulse which completely inhibited the flowering. Treating the plants with KCN blocked the inhibiting effect of red light. Because KCN lowers considerably the rate of destruction of labile Pfd in some plant systems, it seems probable that red light night-break irradiation (without KCN, which blocked the flowering, leads also to the accumulation of unknown Pfd destruction products (irreversible phytochrome. It also suggests that it is not the labile PfrI itself but the products of its irreversible transformation that could be active in the photoperiodic control of flowering.

  18. Capital dissipation minimization for a class of complex irreversible resource exchange processes

    Science.gov (United States)

    Xia, Shaojun; Chen, Lingen

    2017-05-01

    A model of a class of irreversible resource exchange processes (REPes) between a firm and a producer with commodity flow leakage from the producer to a competitive market is established in this paper. The REPes are assumed to obey the linear commodity transfer law (LCTL). Optimal price paths for capital dissipation minimization (CDM) (it can measure economic process irreversibility) are obtained. The averaged optimal control theory is used. The optimal REP strategy is also compared with other strategies, such as constant-firm-price operation and constant-commodity-flow operation, and effects of the amount of commodity transferred and the commodity flow leakage on the optimal REP strategy are also analyzed. The commodity prices of both the producer and the firm for the CDM of the REPes with commodity flow leakage change with the time exponentially.

  19. Irreversible binding of o,p'-DDD in interrenal cells of Atlantic cod (Gadus morhua).

    Science.gov (United States)

    Lindhe, Orjan; Brandt, Ingvar; Christiansen, Jørgen Schou; Ingebrigtsen, Kristian

    2003-03-01

    Precision-cut tissue slices of the anterior kidney from Atlantic cod (Gadus morhua) were prepared with a Krumdieck tissue slicer and exposed to 2-(2-chlorophenyl)-2-(4-chloro-(14C)phenyl)-1,1-dichlorethane (o,p(')-[14C]DDD) in vitro. Microautoradiography revealed irreversible o,p(')-DDD-derived binding confined to the glucocorticoid producing interrenal cells (adrenocortical analogues). This cell-selective binding was confirmed by means of autoradiography at different levels of resolution on Atlantic cod administered o,p(')-[14C]DDD intragastrically. The results provide evidence for a site-specific metabolic activation and irreversible binding of o,p(')-DDD in the interrenal cells, which, in turn, may modify glucocorticoid homeostasis.

  20. Irreversible and irretrievable commitments of material resources (Revision 1) - June 1976

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    In accordance with 10 CFR Part 51, Licensing and Regulatory Policy and Procedures for Environmental Protection, applicants are required to discuss any irreversible and irretrievable commitments of resources that would be involved in a proposed action, should it be implemented. The construction and operation of nuclear power stations involve commitments of such resources as water, fuel and materials. The guide presented identifies a report on material resources that forms a basis acceptable to the NRC staff for required discussions of irreversible and irretrievable commitments of material resources involved in the construction of a 1000 MWe pressurized water reactor. The guide describes numerical estimates useful in all such discussions. It also provides methods of computation that may be referenced

  1. [Fourth update of the guidelines on determination of irreversible brain death. Procedural course and amendments].

    Science.gov (United States)

    Tonn, J-C

    2016-02-01

    In 2015 the fourth update of the directive for the determination of definitely irreversible loss of complete function of the cerebrum, cerebellum and brainstem was passed and came into force. This was preceded by several hearings of all professional societies and associations involved as well as a 2-year advisory process of an interdisciplinary working party. The directive is intended to determine irreversible brain death in the field of intensive care medicine and is independent of individual decisions about organ donation. Not only an update based on scientific data but also a clarification of the several procedures and a clear definition of the medical qualifications required were worked out. Furthermore, the technical procedures computed tomography (CT) angiography and duplex sonography were adopted for the diagnosis of cerebral circulatory arrest. The new directive including comprehensive explanatory notes was approved by the German Federal Ministry of Health and published by the German Medical Council (Bundesärztekammer).

  2. Linear irreversible thermodynamics and Onsager reciprocity for information-driven engines

    Science.gov (United States)

    Yamamoto, Shumpei; Ito, Sosuke; Shiraishi, Naoto; Sagawa, Takahiro

    2016-11-01

    In the recent progress in nonequilibrium thermodynamics, information has been recognized as a kind of thermodynamic resource that can drive thermodynamic current without any direct energy injection. In this paper, we establish the framework of linear irreversible thermodynamics for a broad class of autonomous information processing. In particular, we prove that the Onsager reciprocity holds true with information: The linear response matrix is well-defined and is shown symmetric with both of the information affinity and the conventional thermodynamic affinity. As an application, we derive a universal bound for the efficiency at maximum power for information-driven engines in the linear regime. Our result reveals the fundamental role of information flow in linear irreversible thermodynamics.

  3. Long Memory and Structural Breaks in Realized Volatility: An Irreversible Markov Switching Approach

    DEFF Research Database (Denmark)

    Nonejad, Nima

    This paper proposes a model that simultaneously captures long memory and structural breaks. We model structural breaks through irreversible Markov switching or so-called change-point dynamics. The parameters subject to structural breaks and the unobserved states which determine the position...... to daily S&P 500 data, one finds strong evidence of three structural breaks. The evidence of these breaks is robust to different specifications including a GARCH specification for the conditional variance of volatility....

  4. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Rôças, Isabela N; Alves, Flávio R F; Rachid, Caio T C C; Lima, Kenio C; Assunção, Isauremi V; Gomes, Patrícia N; Siqueira, José F

    2016-01-01

    This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

  5. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

    Directory of Open Access Journals (Sweden)

    Isabela N Rôças

    Full Text Available This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%, Pseudoramibacter (10.7% and Streptococcus (5.5%. Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

  6. Macroscopic irreversibility and microscopic paradox: A Constructal law analysis of atoms as open systems

    OpenAIRE

    Umberto Lucia

    2016-01-01

    The relation between macroscopic irreversibility and microscopic reversibility is a present unsolved problem. Constructal law is introduced to develop analytically the Einstein?s, Schr?dinger?s, and Gibbs? considerations on the interaction between particles and thermal radiation (photons). The result leads to consider the atoms and molecules as open systems in continuous interaction with flows of photons from their surroundings. The consequent result is that, in any atomic transition, the ene...

  7. Conducts of disinfection, pouring and storage of irreversible hydrocolloid impressions by undergraduate students

    Directory of Open Access Journals (Sweden)

    Thalisson Saymo de Oliveira SILVA

    Full Text Available Abstract Introduction Obtaining dental models that accurately represent the molded oral tissue requires professional attention, especially when using irreversible hydrocolloid as a molding material. Objective To evaluate the conducts of undergraduate dental students at different internships for the disinfecting procedures, pouring, and storage of irreversible hydrocolloid impressions. Material and method This is an observational, cross-sectional and descriptive study with a census sample of 89 students enrolled in the supervised internships I, II, III and IV. Data collection was performed using a structured questionnaire containing eight questions. Data were analyzed at the 5% significance level. Result Most of the students (88.8% performed the disinfection procedure, for which the most widely used method (64.6% was the application of sodium hypochlorite 1% spray stored in a sealed container. The most common disinfection time was 10 minutes (86.1%. Students in the early internships performed better in regard to the proportion of water/plaster to be used compared with students in the final internships. At all internships, pouring and storage of the ensemble of mold and model were neglected during the setting reaction. There was a statistically significant association between the stage and the disinfection method, the ratio of water/powder and pouring of the model (p<0.05. Conclusion Students exhibited appropriate conduct of disinfection; however, they should be encouraged to use evidence-based clinical practices in order to improve the procedures of pouring and storage of irreversible hydrocolloid molds.

  8. Calcium-Enriched Mixture Pulpotomy of Primary Molar Teeth with Irreversible Pulpitis. A Clinical Study.

    Science.gov (United States)

    Memarpour, Mahtab; Fijan, Soleiman; Asgary, Saeed; Keikhaee, Marzieh

    2016-01-01

    To evaluate the outcome of vital pulp therapy in primary teeth with irreversible pulpitis by using calcium-enriched mixture (CEM) cement according to clinical and radiographic assessment. Fifty primary molar teeth with irreversible pulpitis in 50 children aged 6-8 years underwent pulpotomy using CEM cement as the dressing material. Following pulpotomy, pain intensity was evaluated by use of a visual analog scale at 1 and 7 days from the treatment and in clinical appointments at 3, 6 and 12 months after baseline. Radiographic evaluation was performed at 6 and 12 months. Data were analyzed using the McNemar test. A total of 42 children (mean age 7.26 ± 0.82 year) completed the study. After one day treatment 56 % of children reported complete relief of pain and after 7 days 62% reported the same. However, two children complained of increased pain 1 day after treatment. None of the children reported pain in the subsequent appointments. One child complained of tenderness in percussion after 6 months. Pulp canal obliteration was the most common change in the radiographic assessment. There was no significant difference between clinical (92.8%) and radiographic (90.4%) success (p=0.990). Pulpotomy using CEM cement could present a successful treatment in primary molar teeth with irreversible pulpitis.

  9. Calcium-Enriched Mixture Pulpotomy of Primary Molar Teeth with Irreversible Pulpitis. A Clinical Study

    Science.gov (United States)

    Memarpour, Mahtab; Fijan, Soleiman; Asgary, Saeed; Keikhaee, Marzieh

    2016-01-01

    Objectives: To evaluate the outcome of vital pulp therapy in primary teeth with irreversible pulpitis by using calcium-enriched mixture (CEM) cement according to clinical and radiographic assessment. Participants and Methods: Fifty primary molar teeth with irreversible pulpitis in 50 children aged 6-8 years underwent pulpotomy using CEM cement as the dressing material. Following pulpotomy, pain intensity was evaluated by use of a visual analog scale at 1 and 7 days from the treatment and in clinical appointments at 3, 6 and 12 months after baseline. Radiographic evaluation was performed at 6 and 12 months. Data were analyzed using the McNemar test. Results: A total of 42 children (mean age 7.26 ± 0.82 year) completed the study. After one day treatment 56 % of children reported complete relief of pain and after 7 days 62% reported the same. However, two children complained of increased pain 1 day after treatment. None of the children reported pain in the subsequent appointments. One child complained of tenderness in percussion after 6 months. Pulp canal obliteration was the most common change in the radiographic assessment. There was no significant difference between clinical (92.8%) and radiographic (90.4%) success (p=0.990). Conclusion: Pulpotomy using CEM cement could present a successful treatment in primary molar teeth with irreversible pulpitis. PMID:27326265

  10. Coupled Reversible and Irreversible Bistable Switches Underlying TGFβ-induced Epithelial to Mesenchymal Transition

    Science.gov (United States)

    Tian, Xiao-Jun; Zhang, Hang; Xing, Jianhua

    2013-01-01

    Epithelial to mesenchymal transition (EMT) plays an important role in embryonic development, tissue regeneration, and cancer metastasis. Whereas several feedback loops have been shown to regulate EMT, it remains elusive how they coordinately modulate EMT response to TGF-β treatment. We construct a mathematical model for the core regulatory network controlling TGF-β-induced EMT. Through deterministic analyses and stochastic simulations, we show that EMT is a sequential two-step program in which an epithelial cell first is converted to partial EMT then to the mesenchymal state, depending on the strength and duration of TGF-β stimulation. Mechanistically the system is governed by coupled reversible and irreversible bistable switches. The SNAIL1/miR-34 double-negative feedback loop is responsible for the reversible switch and regulates the initiation of EMT, whereas the ZEB/miR-200 feedback loop is accountable for the irreversible switch and controls the establishment of the mesenchymal state. Furthermore, an autocrine TGF-β/miR-200 feedback loop makes the second switch irreversible, modulating the maintenance of EMT. Such coupled bistable switches are robust to parameter variation and molecular noise. We provide a mechanistic explanation on multiple experimental observations. The model makes several explicit predictions on hysteretic dynamic behaviors, system response to pulsed stimulation, and various perturbations, which can be straightforwardly tested. PMID:23972859

  11. How Effective Is Supplemental Intraseptal Anesthesia in Patients with Symptomatic Irreversible Pulpitis?

    Science.gov (United States)

    Webster, Stephen; Drum, Melissa; Reader, Al; Fowler, Sara; Nusstein, John; Beck, Mike

    2016-10-01

    Previous studies have reported high levels of success with intraseptal injection for various dental procedures but provide limited information on the use of the injection during endodontic treatment. Therefore, the purpose of this prospective study was to determine the anesthetic efficacy of the supplemental intraseptal technique in mandibular posterior teeth diagnosed with symptomatic irreversible pulpitis when the conventional inferior alveolar nerve (IAN) block failed. One hundred patients with a diagnosis of symptomatic irreversible pulpitis in a mandibular posterior tooth were recruited. Following profound lip numbness after the administration of the conventional IAN block, endodontic treatment was initiated. Patients still experiencing moderate to severe pain during treatment were administered mesial and distal supplemental intraseptal injections using 0.7 mL 4% articaine with 1:000,000 epinephrine administered with a computer-controlled local anesthetic delivery unit. Success was defined as the ability to perform endodontic access and instrumentation with mild to no pain. Success with the IAN block was achieved in 25% of patients. Supplemental intraseptal injections provided success in 29% of patients. Supplemental intraseptal injections achieved profound pulpal anesthesia in 29% of patients when the IAN block failed. This low level of success would not provide predictable levels of anesthesia for patients requiring emergency endodontic treatment for symptomatic irreversible pulpitis in mandibular posterior teeth. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Endothelial dysfunction and atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease

    International Nuclear Information System (INIS)

    Çiftel, Murat; Şimşek, Ayse; Turan, Özlem; Kardelen, Firat; Akçurin, Gayaz; Ertuğ, Halil

    2012-01-01

    To assess endothelial dysfunction and the risk for coronary atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease (CHD). The study included 18 cyanotic patients (the mean age was 12.28 ± 3.26 years) who developed irreversible pulmonary hypertension due to cyanotic and acyanotic CHDs, and 18 control patients (the mean age was 11.78 ± 3.00 years). Study groups were compared for flow-mediated dilatation (FMD), carotid intima media thickness (CIMT) and atherosclerotic risk factors. Compared to the control group, the mean FMD was significantly reduced in the cyanotic group (5.26 ± 2.42% and 9.48 ± 2.60%, respectively; P-value < 0.001). No significant difference was observed between the groups in CIMT (0.41 ± 0.08 mm and 0.39 ± 0.06 mm, respectively; P-value = 0.299). The levels of total cholesterol, low-density lipoprotein–cholesterol and very low-density lipoprotein–cholesterol were statistically significantly lower compared tothe control group (P-value = 0.001, 0.006 and 0.014, respectively), whereas no statistically significant difference was found in the levels of high-density lipoprotein–cholesterol and triglycerides (P-value = 0.113 and 0.975, respectively). Systemic endothelial dysfunction in children with irreversible pulmonary hypertension due to CHD was noted but there was no increased risk for atherosclerosis

  13. Parametric optimization of an irreversible magnetic Ericsson refrigerator with finite heat reservoirs

    International Nuclear Information System (INIS)

    Ye, X.M.; Lin, G.X.; Chen, J.C.; Brueck, E.

    2007-01-01

    An irreversible cycle model of magnetic Ericsson refrigerators is established, in which the finite heat capacities of external heat reservoirs, heat-transfer irreversibility, inherent regenerative losses, additional regenerative losses due to thermal resistances and irreversibility inside the magnetic working substances are taken into account. On the basis of the thermodynamic equations of paramagnetic materials, the performance characteristics of the magnetic Ericsson refrigeration cycle are investigated. By using the method of the optimal control theory, the optimal equations between the cooling load and the coefficient of performance and between the cooling load and the power input are derived. Furthermore, the maximum cooling load and the corresponding coefficient of performance, the minimum power input and the optimally operating temperatures of the cyclic working substance are obtained. The optimal operating region of the magnetic Ericsson refrigerator is determined. The results obtained here are closer to the performance characteristics of practical magnetic refrigerators with finite heat reservoirs than those in literature and are helpful to the optimal design and performance improvement of magnetic Ericsson refrigerators

  14. Origin of the irreversibility line in thin YBa2Cu3O7-δ films with and without columnar defects

    International Nuclear Information System (INIS)

    Prozorov, R.; Konczykowski, M.; Schmidt, B.; Yeshurun, Y.; Shaulov, A.; Villard, C.; Koren, G.

    1996-01-01

    We report on measurements of the angular dependence of the irreversibility temperature T irr (θ) in YBa 2 Cu 3 O 7-δ thin films, defined by the onset of a third-harmonic signal and measured by a miniature Hall probe. From the functional form of T irr (θ) we conclude that the origin of the irreversibility line in unirradiated films is a dynamic crossover from an unpinned to a pinned vortex liquid. In irradiated films the irreversibility temperature is determined by the trapping angle. copyright 1996 The American Physical Society

  15. Concerning the study of the irreversible magnetic behaviour of superconductivity; Contribution a l'etude du comportement magnetique irreversible des supraconducteurs

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, G. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-03-01

    The influence of the presence of extended lattice defects on the magnetic behaviour has been studied for the case of type I superconductors, such as Re and Ta, and in a more quantitative manner for the type II superconductor niobium. In this case, measurements of the thermal conductivity have given an estimate of the relative concentration of lattice defects in each specimen. These measurements show that the larger the number of lattice defects, the more irreversible becomes the magnetization curve, and the larger becomes the values of the critical current, which is related by a simple model to the magnetization values. Finally, a study by transmission electron microscopy has confirmed on the one hand the diversity of the extended lattice defects and on the other hand has allowed the formulation of several hypothesis on their respective influence. [French] L'influence de la presence de defauts etendus sur le comportement magnetique a ete etudie pour des supraconducteurs de premiere espece, tels que le rhenium et le tantale, et plus quantitativement pour un supraconducteur de deuxieme espece, le niobium. Dans ce cas, des mesures de conductibilite thermique ont permis d'estimer la concentration relative des defauts du reseau dans chaque echantillon. Ces mesures montrent que plus les defauts du reseau sont nombreux, plus la courbe d'aimantation est irreversible, et plus les valeurs du courant critique, reliees par un modele simple aux valeurs de l'aimantation, sont elevees. Enfin une etude par microscopie electronique en transmission - a permis d'une part de constater la diversite des defauts etendus et d'autre part de formuler quelques hypotheses sur leurs influences respectives.

  16. Osteomielitis por salmonella

    Directory of Open Access Journals (Sweden)

    Alicia Velázquez Pérez

    2014-08-01

    Full Text Available Se presenta el caso de una paciente femenina de color blanco y dos años de edad, con diagnóstico prenatal de sicklemia, que desde edades tempranas tiene problemas de la enfermedad. Ingresó en esta ocasión por una de las complicaciones infecciosas que ocasiona este padecimiento, una osteomielitis del húmero izquierdo, aislándose el germen en el hemocultivo realizado, una salmonella. Necesitó de tratamiento enérgico y prolongado; se obtuvo un resultado satisfactorio en la evolución de la enfermedad y se sigue sistemáticamente por consulta externa en la actualidad

  17. Apendicitis por Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Ana Beatriz MUÑOZ URRIBARRI

    2006-01-01

    Full Text Available La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis por esta patología. (Rev Med Hered 2006;17:58-60.

  18. The Thermodynamic Continuum of Jet Engine Performance: The Principle of Lost Work due to Irreversibility in Aerospace Systems

    OpenAIRE

    Riggins, David

    2003-01-01

    The performance continuum for air-breathing engines is formally developed and illustrated in terms of fundamental thermodynamic quantities including heat and work interactions and the irreversibility occurring in the flow-path of the engine. The thermodynamically consistent base-line from which performance losses due to irreversibility must be measured is clearly defined based on this analysis. Issues and problems with conventional flow availability (flow exergy) in terms of the assessment (d...

  19. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells

    OpenAIRE

    Soichiro Sonoda; Haruyoshi Yamaza; Lan Ma; Yosuke Tanaka; Erika Tomoda; Reona Aijima; Kazuaki Nonaka; Toshio Kukita; Songtao Shi; Fusanori Nishimura; Takayoshi Yamaza

    2016-01-01

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we...

  20. Optimal allocation of thermodynamic irreversibility for the integrated design of propulsion and thermal management systems

    Science.gov (United States)

    Maser, Adam Charles

    work losses over the time history of the mission. The characterization of the thermodynamic irreversibility distribution helps give the propulsion systems designer an absolute and consistent view of the tradeoffs associated with the design of the entire integrated system. Consequently, this leads directly to the question of the proper allocation of irreversibility across each of the components. The process of searching for the most favorable allocation of this irreversibility is the central theme of the research and must take into account production cost and vehicle mission performance. The production cost element is accomplished by including an engine component weight and cost prediction capability within the system model. The vehicle mission performance is obtained by directly linking the propulsion and thermal management model to a vehicle performance model and flying it through a mission profile. A canonical propulsion and thermal management systems architecture is then presented to experimentally test each element of the methodology separately: first the integrated modeling and simulation, then the irreversibility, cost, and mission performance considerations, and then finally the proper technique to perform the optimal allocation. A goal of this research is the description of the optimal allocation of system irreversibility to enable an engine cycle design with improved performance and cost at the vehicle-level. To do this, a numerical optimization was first used to minimize system-level production and operating costs by fixing the performance requirements and identifying the best settings for all of the design variables. There are two major drawbacks to this approach: It does not allow the designer to directly trade off the performance requirements and it does not allow the individual component losses to directly factor into the optimization. An irreversibility allocation approach based on the economic concept of resource allocation is then compared to the

  1. Miotoxicidade por organofosforados

    Directory of Open Access Journals (Sweden)

    Cavaliere Maria J.

    1996-01-01

    Full Text Available Os organofosforados são um grupo de compostos químicos amplamente utilizados em agropecuária como inseticidas, ocasionando intoxicações acidentais em animais e humanos, e mesmo sendo utilizados em tentativas de suicídio. A toxicidade desses produtos decorre sobretudo de insuficiência cárdio-respiratória por compromentimento do sistema nervoso autônomo. Sabe-se que alguns destes compostos induzem em animais de experimentação e em humanos, uma miopatia caracterizada por degeneração de células musculares, comprometendo sobretudo a musculatura respiratória. Baseado no fato de que este comprometimento contribui para a piora da função respiratória, propõe-se um protocolo de avaliação rotineira de miotoxicidade por compostos organofosforados, através de uma bateria mínima e suficiente de colorações e reações histoquímicas para quantificação da necrose muscular. Utilizaram-se como modelo experimental, grupos de ratos albinos (Wistar intoxicados com o organofosforado paraoxon, com e sem antídotos (atropina ou pralidoxima. Verificou-se nos grupos tratados com paraoxon e paraoxon mais atropina, necrose de fibras musculares no diafragma, que atingia em determinadas áreas até 15% das fibras. No grupo tratado com paraoxon mais pralidoxima, a necrose foi mínima, evidenciando o papel mioprotetor deste último antídoto.

  2. Reversible and irreversible magnetization of the Chevrel-phase superconductor PbMo6S8

    International Nuclear Information System (INIS)

    Zheng, D.N.; Ramsbottom, H.D.; Hampshire, D.P.

    1995-01-01

    Magnetic measurements have been carried out on the hot-isostatically-pressed Chevrel-phase superconductor PbMo 6 S 8 at temperatures from 4.2 K to T c and for magnetic fields up to 12 T. The results show that for the PbMo 6 S 8 compound there is a wide magnetically reversible region, between the irreversibility field B irr and the upper critical field B c2 , on the isothermal magnetic hysteresis curves. The B irr (T) line, i.e., the irreversibility line, was found to obey a power-law expression: B irr =B * (1-T/T c ) α with α∼1.5. Magnetic relaxation measurements revealed that the flux-creep effect in the material studied is substantial and is greater than those observed in conventional metallic alloys, but smaller than in high-temperature superconductors. The existence of the irreversibility line and pronounced flux-creep effect in PbMo 6 S 8 is attributed to the short coherence length of the material. From the reversible magnetization data, the values of the penetration depth, the coherence length, and the critical fields are obtained together with the Ginzburg-Landau parameter κ. At 4.2 K, the critical current density J c is 10 9 A m -2 at zero field, and decreases to 2x10 8 A m -2 at 10 T. Pinning force curves measured at different temperatures obey a Kramer-scaling law of the form: F p (=J c xB)∝b 1/2 (1-b) 2 , which indicates that the J c is limited by one predominant flux-pinning mechanism

  3. Outcome of full pulpotomy using Biodentine in adult patients with symptoms indicative of irreversible pulpitis.

    Science.gov (United States)

    Taha, N A; Abdelkhader, S Z

    2018-02-03

    To assess the outcome of full pulpotomy using Biodentine in permanent teeth with carious exposures and symptoms indicative of irreversible pulpitis. Sixty-four permanent molar teeth with symptomatic vital pulps in 52 patients aged 19-69 years were included. Preoperative pulpal and periapical diagnosis was established. After informed consent, the tooth was anaesthetized, isolated using rubber dam and disinfected with 5% NaOCl before caries excavation; subsequently, the pulp was amputated to the level of the canal orifices. Haemostasis was achieved, and a 3-mm layer of Biodentine (Septodont, Saint-Maur-des-Fosses, France) was placed as the pulpotomy agent. Resin-modified glass-ionomer liner was placed and the tooth restored with either resin composite or amalgam, and a postoperative periapical radiograph exposed. Clinical and radiographic evaluation was completed at 6 months and 1 year postoperatively. Pain levels were scored preoperatively and 2 days post-treatment. Clinical signs and symptoms indicative of irreversible pulpitis were established in all teeth, and periapical rarefaction was present in nine teeth. After 2 days, 93.8% reported complete relief of pain. At 6 months, 63 of 64 attended recall with 98.4% clinical and radiographic success. At 1 year, 59 of 63 attended recall, with 100% clinical and 98.4 radiographic success. Seven of eight cases with periapical rarefaction who attended recall had improvement in the periapical index (PAI) score. A hard tissue barrier was detected radiographically in four cases. Full pulpotomy using Biodentine was a successful treatment option for cariously exposed pulps in mature permanent molar teeth with clinical signs and symptoms indicative of irreversible pulpitis, up to 1 year. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  4. Anaesthetic efficacy of lidocaine/clonidine for inferior alveolar nerve block in patients with irreversible pulpitis.

    Science.gov (United States)

    Shadmehr, E; Aminozarbian, M G; Akhavan, A; Mahdavian, P; Davoudi, A

    2017-06-01

    This prospective, randomized, double-blind study aimed to compare the efficacy of lidocaine with epinephrine versus lidocaine with clonidine for inferior alveolar nerve block (IANB) and hemodynamic stability (heart rate, systolic blood pressure, diastolic blood pressure and mean arterial pressure) in patients with irreversible pulpitis. One hundred patients with irreversible pulpitis in mandibular molar teeth randomly received 1.8 mL of 2% lidocaine with clonidine (15 μg mL -1 ) or 1.8 mL of 2% lidocaine with epinephrine (12.5 μg mL -1 ), using a conventional IANB technique. Endodontic access cavities were prepared 15 min after solution deposition, and all patients were required to have profound lip numbness. Success was defined as no or mild pain (visual analog scale recording) upon endodontic access cavity preparation or initial canal instrumentation. The hemodynamic parameters were measured before, during and 5, 10 and 30 min after administration. Finally, the collected data were subjected to independent t-test, chi-square and Fisher's exact test using spss software ver.20 at a significant level of 0.05. The success rates for IANB using lidocaine with epinephrine and lidocaine with clonidine solutions were 29% and 59%, respectively. The clonidine group exhibited a significantly higher success rate (P irreversible pulpitis, addition of clonidine to lidocaine improved the success rate of IANB compared to a standard lidocaine/epinephrine solution. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  5. Histologic Findings of a Human Immature Revascularized/Regenerated Tooth with Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Peng, Chufang; Zhao, Yuming; Wang, Wenjun; Yang, Yuan; Qin, Man; Ge, Lihong

    2017-06-01

    Pulp revascularization/regeneration in immature permanent teeth with necrotic pulp and/or apical periodontitis is an effective approach for inducing root maturation. Previous histologic studies showed cementoid/osteoid tissue and/or periodontal ligament-like tissue formed within the root canals. This case report describes the histologic findings of a human symptomatic irreversible pulpitis immature permanent tooth with most of the pulp removed after a revascularization/regeneration procedure. A human immature permanent mandibular premolar (tooth #29) was diagnosed as symptomatic irreversible pulpitis with symptomatic apical periodontitis at the emergency department. Most of the pulp was removed. The tooth was treated with revascularization/regeneration. At the 12-month recall, the radiographic examination revealed thickening of the root canal wall, narrowing of the root apex, and lengthening of the root. The tooth was extracted at 12 months for orthodontic treatment. The specimens were processed for histologic examination. Histologically, the apical third of the root canal was filled with newly formed dentinlike and pulplike tissue. There was a layer of flattened odontoblastlike cells lining the dentinal wall. In the midportion of the root canal, the newly formed dentinlike tissue gradually changed to cementumlike tissue. In the upper third of the root canal, there was a presence of cementocytelike cells housed in the lacunae of cementumlike tissue around the loose connective tissue. In the present case, regeneration of the pulplike tissue and the periodontium existed after a revascularization/regeneration procedure in an immature permanent tooth clinically diagnosed as symptomatic irreversible pulpitis. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. The anti-inflammatory effects of matrix metalloproteinase-3 on irreversible pulpitis of mature erupted teeth.

    Science.gov (United States)

    Eba, Hisanori; Murasawa, Yusuke; Iohara, Koichiro; Isogai, Zenzo; Nakamura, Hiroshi; Nakamura, Hiroyuki; Nakashima, Misako

    2012-01-01

    Matrix metalloproteinases (MMPs) are involved in extracellular matrix degradation and the modulation of cell behavior. These proteinases have also been implicated in tissue repair and regeneration. Our previous studies have demonstrated that MMP-3 elicits stimulatory effects on the proliferation and the migration of endothelial cells as well as anti-apoptotic effects on these cells in vitro. In addition, we found that MMP-3 enhanced the regeneration of lost pulp tissue in a rat incisor pulp injury model. However, continuously erupting rodent incisors exhibit significantly different pulp organization compared with mature erupted teeth. Therefore, we have further extended these studies using a canine irreversible pulpitis model to investigate the effects of MMP-3. In this study, the crowns of the canine mature premolars were removed and the pulp tissues were amputated. The amputated pulp tissues remained exposed for 24 or 72 hours to induce mild or severe irreversible pulpitis, respectively, followed by sealing of the cavities. In both models, the whole pulp tissues became necrotic by day 14. In this mild pulpitis model, the regeneration of pulp tissue with vasculature and nerves was observed until 14 days after sealing with MMP-3, followed by extracellular matrix formation in the regenerated pulp tissues until day 28. The treatment with MMP-3 resulted in a decrease in the number of macrophage and antigen-presenting cells and a significant inhibition of IL-6 expression on day 3. The inhibition of MMP-3 activity abolished these anti-inflammatory effects. Immunofluorescence staining demonstrated that MMP-3 was involved in the modification of serum-derived hyaluronan-associated proteins and hyaluronan (SHAP-HA) complexes possibly through the degradation of versican. These results demonstrate that MMP-3 can act as an anti-inflammatory agent and suggest that MMP-3 might represent a useful therapy for the treatment of mild irreversible pulpitis.

  7. The anti-inflammatory effects of matrix metalloproteinase-3 on irreversible pulpitis of mature erupted teeth.

    Directory of Open Access Journals (Sweden)

    Hisanori Eba

    Full Text Available Matrix metalloproteinases (MMPs are involved in extracellular matrix degradation and the modulation of cell behavior. These proteinases have also been implicated in tissue repair and regeneration. Our previous studies have demonstrated that MMP-3 elicits stimulatory effects on the proliferation and the migration of endothelial cells as well as anti-apoptotic effects on these cells in vitro. In addition, we found that MMP-3 enhanced the regeneration of lost pulp tissue in a rat incisor pulp injury model. However, continuously erupting rodent incisors exhibit significantly different pulp organization compared with mature erupted teeth. Therefore, we have further extended these studies using a canine irreversible pulpitis model to investigate the effects of MMP-3. In this study, the crowns of the canine mature premolars were removed and the pulp tissues were amputated. The amputated pulp tissues remained exposed for 24 or 72 hours to induce mild or severe irreversible pulpitis, respectively, followed by sealing of the cavities. In both models, the whole pulp tissues became necrotic by day 14. In this mild pulpitis model, the regeneration of pulp tissue with vasculature and nerves was observed until 14 days after sealing with MMP-3, followed by extracellular matrix formation in the regenerated pulp tissues until day 28. The treatment with MMP-3 resulted in a decrease in the number of macrophage and antigen-presenting cells and a significant inhibition of IL-6 expression on day 3. The inhibition of MMP-3 activity abolished these anti-inflammatory effects. Immunofluorescence staining demonstrated that MMP-3 was involved in the modification of serum-derived hyaluronan-associated proteins and hyaluronan (SHAP-HA complexes possibly through the degradation of versican. These results demonstrate that MMP-3 can act as an anti-inflammatory agent and suggest that MMP-3 might represent a useful therapy for the treatment of mild irreversible pulpitis.

  8. Factors affecting the selection of a reversible or an irreversible contraceptive method in a developing country.

    Science.gov (United States)

    Ozalp, S; Yalcin, O T; Hassa, H; Erbay, B; Dalan, N

    2000-06-01

    To evaluate the factors that may affect the selection of a reversible or an irreversible contraceptive method. In an urban area of a developing country, demographic characteristics, educational and income levels, and previously used contraceptive methods were retrospectively reviewed for 3 years from the files of women who had chosen reversible or irreversible contraceptive methods. Student's t test and the chi2 test were used to analyze the data obtained from the two groups of women. Out of a total of 8078 women, 595 (7.4%) selected surgical sterilization, while 7483 (92.6%) preferred reversible methods such as intrauterine devices (38.1%), combined oral contraceptives (13.9%), condoms (40%) and Norplant (0.6%). Compared to those who preferred reversible methods, the women with surgical sterilization had a higher mean age (33.9 +/- 4.2 years versus 29.6 +/- 3.9 years), mean gravidity (3.8 +/- 0.9 versus 2.3 +/- 1.2) and mean number of living children (2.6 +/- 0.8 versus 2.1 +/- 1.1) (p < 0.01). These women had also higher rates of high-school education (37.3% versus 30.1%) and previous modern contraceptive use (78.1% versus 71.2%) (p < 0.01). None of the women with surgical sterilization, but 1770 (33.0%) of those who chose reversible methods, had fewer than two living children. These data suggest that irreversible contraceptive methods tend to be chosen by older women with higher educational levels, who have decided that their family is complete and who have at least two children.

  9. A Derivation of a Microscopic Entropy and Time Irreversibility From the Discreteness of Time

    Directory of Open Access Journals (Sweden)

    Roland Riek

    2014-06-01

    Full Text Available The basic microsopic physical laws are time reversible. In contrast, the second law of thermodynamics, which is a macroscopic physical representation of the world, is able to describe irreversible processes in an isolated system through the change of entropy ΔS > 0. It is the attempt of the present manuscript to bridge the microscopic physical world with its macrosocpic one with an alternative approach than the statistical mechanics theory of Gibbs and Boltzmann. It is proposed that time is discrete with constant step size. Its consequence is the presence of time irreversibility at the microscopic level if the present force is of complex nature (F(r ≠ const. In order to compare this discrete time irreversible mechamics (for simplicity a “classical”, single particle in a one dimensional space is selected with its classical Newton analog, time reversibility is reintroduced by scaling the time steps for any given time step n by the variable sn leading to the Nosé-Hoover Lagrangian. The corresponding Nos´e-Hoover Hamiltonian comprises a term Ndf kB T ln sn (kB the Boltzmann constant, T the temperature, and Ndf the number of degrees of freedom which is defined as the microscopic entropy Sn at time point n multiplied by T. Upon ensemble averaging this microscopic entropy Sn in equilibrium for a system which does not have fast changing forces approximates its macroscopic counterpart known from thermodynamics. The presented derivation with the resulting analogy between the ensemble averaged microscopic entropy and its thermodynamic analog suggests that the original description of the entropy by Boltzmann and Gibbs is just an ensemble averaging of the time scaling variable sn which is in equilibrium close to 1, but that the entropy

  10. Por mil devaluados pesos

    Directory of Open Access Journals (Sweden)

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  11. Infecciones por citomegalovirus

    Directory of Open Access Journals (Sweden)

    Ana Gloria Díaz Martínez

    1998-06-01

    Full Text Available Se ofrece una revisión actualizada sobre la infección por citomegalovirus a partir de la consulta de artículos referidos de 1990 a 1996 en las bases de datos MEDLINE, LILACS, Literatura Cubana de Medicina y Noticias de Salud. Se revisaron 37 artículos. Se abordan los aspectos más importantes de las manifestaciones clínicas, el diagnóstico, el tratamiento, así como la prevención y los métodos de control para evitar las enfermedades citomegálicas

  12. Irreversible transformation of the porphyrin supramolecular structures under a water vapor environment

    International Nuclear Information System (INIS)

    Ye Ming; Zhang Yi

    2011-01-01

    Supramolecular structures formed by H 4 TPPS 4 2- have been widely used for different applications. In this paper, the stability of H 4 TPPS 4 2- nanorods on mica substrate is investigated by atom force microscopy (AFM) observation.An irreversible transformation of H 4 TPPS 4 2- from nanorods (3.8±0.4 nm in height) to a lower film structure (1.9±0.4 nm in height) was found with the samples incubated at various relative humidities (RH). The transformation rate depends strongly on the RH and environment temperature. (authors)

  13. Irreversible thermochromic behavior in gold and silver nanorod/polymeric ionic liquid nanocomposite films.

    Science.gov (United States)

    Tollan, Christopher M; Marcilla, Rebeca; Pomposo, Jose A; Rodriguez, Javier; Aizpurua, Javier; Molina, Jon; Mecerreyes, David

    2009-02-01

    The novel application of gold and silver nanorods as irreversible thermochromic dyes in polymeric ionic liquid (PIL) nanocomposites is proposed here. These materials have been synthesized by anion exchange of an imidazolium-based PIL in a solution that also contained gold nanorods. This resulted in the entrapment of the nanoobjects within a solid polymer precipitate. In this article, the effect of the temperature was studied in relation to the change of shape and, consequently, color of the gold or silver nanorods within the films. For the nanocomposites studied here, a maximum of two visual thermochromic transitions was observed for gold nanorods and up to three transitions were observed for silver nanorods.

  14. Thermodynamic restrictions on linear reversible and irreversible thermo-electro-magneto-mechanical processes

    Directory of Open Access Journals (Sweden)

    Sushma Santapuri

    2016-10-01

    In the first part of this paper, linear Thermo-Electro-Magneto-Mechanical (TEMM quasistatic processes are characterized. Thermodynamic stability conditions are further imposed on the linear constitutive model and restrictions on the corresponding material constants are derived. The framework is then extended to irreversible transport phenomena including thermoelectric, thermomagnetic and the state-of-the-art spintronic and spin caloritronic effects. Using Onsager's reciprocity relationships and the dissipation inequality, restrictions on the kinetic coefficients corresponding to charge, heat and spin transport processes are derived. All the constitutive models are accompanied by multiphysics interaction diagrams that highlight the various processes that can be characterized using this framework.

  15. Performance analysis of air-standard Diesel cycle using an alternative irreversible heat transfer approach

    International Nuclear Information System (INIS)

    Al-Hinti, I.; Akash, B.; Abu-Nada, E.; Al-Sarkhi, A.

    2008-01-01

    This study presents the investigation of air-standard Diesel cycle under irreversible heat transfer conditions. The effects of various engine parameters are presented. An alternative approach is used to evaluate net power output and cycle thermal efficiency from more realistic parameters such as air-fuel ratio, fuel mass flow rate, intake temperature, engine design parameters, etc. It is shown that for a given fuel flow rate, thermal efficiency and maximum power output increase with decreasing air-fuel ratio. Also, for a given air-fuel ratio, the maximum power output increases with increasing fuel rate. However, the effect of the thermal efficiency is limited

  16. Irreversible Thermodynamic Bound for the Efficiency of Light-Emitting Diodes

    Science.gov (United States)

    Xue, Jin; Li, Zheng; Ram, Rajeev J.

    2017-07-01

    A thermodynamic model for light-emitting diodes (LEDs) is developed by considering energy and entropy flows in the system. Thermodynamic constraints have previously been considered separately for the reversible process of electroluminescence in LEDs and for light extraction and collimation in other optical systems. By considering both processes in the LED model, an irreversible upper bound for the conversion of electrical energy to optical energy is derived and shown to be higher than unity, but tighter and more realistic than the reversible case. We also model a LED as an endoreversible heat engine where the carrier-transport processes can be directly connected to the elements of a thermodynamic cycle.

  17. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Wang Hongyue [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea, Republic of)], E-mail: seuwhy100@ajou.ac.kr; Zhao Lingling; Zhou Qiangtai; Xu Zhigao [College of Energy and Environment, Southeast University, Nanjing 210096 (China); Kim, Hyung Taek [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea, Republic of)], E-mail: htkim@ajou.ac.kr

    2008-04-15

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters.

  18. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong Yue; Kim, Hyung Taek [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea); Zhao, Ling Ling; Zhou, Qiang Tai; Xu, Zhi Gao [College of Energy and Environment, Southeast University, Nanjing 210096 (China)

    2008-04-15

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters. (author)

  19. Optimal thermoeconomic performance of an irreversible regenerative ferromagnetic Ericsson refrigeration cycle

    International Nuclear Information System (INIS)

    Xu, Zhichao; Guo, Juncheng; Lin, Guoxing; Chen, Jincan

    2016-01-01

    On the basis of the Langevin theory of classical statistical mechanics, the magnetization, entropy, and iso-field heat capacity of ferromagnetic materials are analyzed and their mathematical expressions are derived. An irreversible regenerative Ericsson refrigeration cycle by using a ferromagnetic material as the working substance is established, in which finite heat capacity rates of low and high temperature reservoirs, non-perfect regenerative heat of the refrigeration cycle, additional regenerative heat loss, etc. are taken into account. Based on the regenerative refrigeration cycle model, a thermoeconomic function is introduced as one objective function and optimized with respect to the temperatures of the working substance in the two iso-thermal processes. By means of numerical calculation, the effects of the effective factor of the heat exchangers in high/low temperature reservoir sides, efficiency of the regenerator, heat capacity rate of the low temperature reservoir, and applied magnetic field on the optimal thermoeconomic function as well as the corresponding cooling rate and coefficient of performance are revealed. The results obtained in this paper can provide some theoretical guidance for the optimal design of actual regenerative magnetic refrigerator cycle. - Highlights: • Thermodynamic performance of ferromagnetic material is analyzed. • An irreversible regenerative ferromagnetic Ericsson refrigeration cycle is set up. • The thermoeconomic objective function is introduced and optimized. • Impacts of the thermoeconomic and other parameters are discussed.

  20. Irreversibility and the Point of No Return in the Evolution of Eruptive Active Regions

    Science.gov (United States)

    Georgoulis, Manolis K.

    We combine multiple methods and findings to demonstrate that those eruptive solar active regions that form intense photospheric magnetic polarity inversion lines (PILs) enter a domain of irreversible evolution that will unavoidably force them to erupt at least once, giving rise to a major flare and an associated fast CME. Electric currents, Lorentz forces, free magnetic energy storage, and magnetic helicity, all play major roles in bringing the magnetic configuration on the verge of instability. The inferred irreversibility stems from the conservative properties of magnetic helicity in high magnetic Reynolds-number plasmas. In addition, the long-standing and fiercely debated classification of eruptive magnetic structures into sheared arcades and flux ropes is found to be of relatively little meaning: by means of the evolution above, the simplest possible sheared-arcade structure may gradually evolve into a flux rope susceptible to the helical-kink and the torus instabilities, among other destabilization mechanisms. Research partially supported by the EU Seventh Framework Programme under grant agreement No. PIRG07-GA-2010-268245 and by the European Union Social Fund (ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Thales. Investing in knowledge society through the European Social Fund.

  1. Performance evaluation and optimization of fluidized bed boiler in ethanol plant using irreversibility analysis

    Directory of Open Access Journals (Sweden)

    Nugroho Agung Pambudi

    2017-09-01

    Full Text Available This research aims to evaluate the performance of a fluidized bed boiler in an ethanol production plant through exergy and irreversibility analysis. The study also includes the optimization of the pre-heater and the deaerator in order to improve the system efficiency. Operational data from the ethanol production plant was collected between 2015 and early 2016. The total exergy derived from the fuel was determined to be 7783 kJ/s, while the exergy efficiency of the system was found to be 26.19%, with 2214 kJ/s used in steam production, while 71.55% was lost to component irreversibility and waste heat from the pre-heater. The exergy efficiencies of individual components of the system such as the boiler, deaerator, and pre-heater were found to be 25.82%, 40.13%, and 2.617%, respectively, with the pre-heater having the lowest efficiency. Thus, the pre-heater has the highest potential to significantly improve the efficiency of the boiler system. The optimization of the pre-heater shows that a rise in temperature in the outlet of the pre-heater positively affects the exergy efficiency of the deaerator.

  2. Features of alpha-synuclein that could explain the progression and irreversibility of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Scarlet eGallegos

    2015-03-01

    Full Text Available Alpha-synuclein is a presynaptic protein expressed throughout the central nervous system, and it is the main component of Lewy bodies, one of the histopathological features of Parkinson’s disease (PD which is a progressive and irreversible neurodegenerative disorder. The conformational flexibility of α-synuclein allows it to adopt different conformations, i.e. bound to membranes or form aggregates, the oligomers are believed to be the more toxic species. In this review, we will focus on two major features of α-synuclein, transmission and toxicity that could help to understand the pathological characteristics of PD. One important feature of α-synuclein is its ability to be transmitted from neuron to neuron using mechanisms such as endocytosis, plasma membrane penetration or through exosomes, thus propagating the Lewy body pathology to different brain regions thereby contributing to the progressiveness of PD. The second feature of α-synuclein is that it confers cytotoxicity to recipient cells, principally when it is in an oligomeric state. This form causes mitochondrial dysfunction, endoplasmic reticulum stress, oxidative stress, proteasome impairment, disruption of plasma membrane and pore formation, and lead to apoptosis pathway activation and consequent cell death. The complexity of α-synuclein oligomerization and formation of toxic species could be a major factor for the irreversibility of PD and could also explain the lack of successful therapies to halt the disease.

  3. Sarcolemmal blebs and osmotic fragility as correlates of irreversible ischemic injury in preconditioned isolated rabbit cardiomyocytes.

    Science.gov (United States)

    Armstrong, S C; Shivell, L C; Ganote, C E

    2001-01-01

    The hypothesis that irreversible ischemic injury is related to sub-sarcolemmal blebbing and an inherent osmotic fragility of the blebs was tested by subjecting isolated control and ischemically preconditioned (IPC) or calyculin A (CalA)-pretreated (protected) rabbit cardiomyocytes to ischemic pelleting followed by resuspension in 340, 170 or 85 mosmol medium containing trypan blue. At time points from 0-240 min, osmotic fragility was assessed by the percentage of trypan blue permeable cells. Membrane blebs were visualized with India ink preparations. Bleb formation, following acute hypo-osmotic swelling, developed by 75 min and increased with longer periods of ischemia. Osmotic fragility developed only after 75 min. Cells resuspended in 340 mosmol media did not form blebs and largely retained the ability to exclude trypan blue, even after 240 min ischemia. Although the latent tendency for osmotic blebbing preceded the development of osmotic fragility, most osmotically fragile cells became permeable without evident sarcolemmal bleb formation. The onset of osmotic fragility was delayed in protected cells, but protection did not reduce the bleb formation. It is concluded that blebbing and osmotic fragility are independent manifestations of ischemic injury. The principal locus of irreversible ischemic injury and the protection provided by IPC may lie within the sarcolemma rather than at sarcolemmal attachments to underlying adherens junctions.

  4. Is the Supraspinatus Muscle Atrophy Truly Irreversible after Surgical Repair of Rotator Cuff Tears?

    Science.gov (United States)

    Chung, Seok Won; Kim, Sae Hoon; Tae, Suk-Kee; Yoon, Jong Pil; Choi, Jung-Ah

    2013-01-01

    Background Atrophy of rotator cuff muscles has been considered an irreversible phenomenon. The purpose of this study is to evaluate whether atrophy is truly irreversible after rotator cuff repair. Methods We measured supraspinatus muscle atrophy of 191 patients with full-thickness rotator cuff tears on preoperative magnetic resonance imaging and postoperative multidetector computed tomography images, taken at least 1 year after operation. The occupation ratio was calculated using Photoshop CS3 software. We compared the change between pre- and postoperative occupation ratios after modifying the preoperative occupation ratio. In addition, possible relationship between various clinical factors and the change of atrophy, and between the change of atrophy and cuff integrity after surgical repair were evaluated. Results The mean occupation ratio was significantly increased postoperatively from 0.44 ± 0.17 to 0.52 ± 0.17 (p < 0.001). Among 191 patients, 81 (42.4%) showed improvement of atrophy (more than a 10% increase in occupation ratio) and 33 (17.3%) worsening (more than a 10% decrease). Various clinical factors such as age tear size, or initial degree of atrophy did not affect the change of atrophy. However, the change of atrophy was related to repair integrity: cuff healing failure rate of 48.5% (16 of 33) in worsened atrophy; and 22.2% (18 of 81) in improved atrophy (p = 0.007). Conclusions The supraspinatus muscle atrophy as measured by occupation ratio could be improved postoperatively in case of successful cuff repair. PMID:23467404

  5. Time-resolved single-shot terahertz time-domain spectroscopy for ultrafast irreversible processes

    Science.gov (United States)

    Zhai, Zhao-Hui; Zhong, Sen-Cheng; Li, Jun; Zhu, Li-Guo; Meng, Kun; Li, Jiang; Liu, Qiao; Peng, Qi-Xian; Li, Ze-Ren; Zhao, Jian-Heng

    2016-09-01

    Pulsed terahertz spectroscopy is suitable for spectroscopic diagnostics of ultrafast events. However, the study of irreversible or single shot ultrafast events requires ability to record transient properties at multiple time delays, i.e., time resolved at single shot level, which is not available currently. Here by angular multiplexing use of femtosecond laser pulses, we developed and demonstrated a time resolved, transient terahertz time domain spectroscopy technique, where burst mode THz pulses were generated and then detected in a single shot measurement manner. The burst mode THz pulses contain 2 sub-THz pulses, and the time gap between them is adjustable up to 1 ns with picosecond accuracy, thus it can be used to probe the single shot event at two different time delays. The system can detect the sub-THz pulses at 0.1 THz-2.5 THz range with signal to noise ratio (SNR) of ˜400 and spectrum resolution of 0.05 THz. System design was described here, and optimizations of single shot measurement of THz pulses were discussed in detail. Methods to improve SNR were also discussed in detail. A system application was demonstrated where pulsed THz signals at different time delays of the ultrafast process were successfully acquired within single shot measurement. This time resolved transient terahertz time domain spectroscopy technique provides a new diagnostic tool for irreversible or single shot ultrafast events where dynamic information can be extracted at terahertz range within one-shot experiment.

  6. Histologic observation of a human immature permanent tooth with irreversible pulpitis after revascularization/regeneration procedure.

    Science.gov (United States)

    Shimizu, Emi; Jong, George; Partridge, Nicola; Rosenberg, Paul A; Lin, Louis M

    2012-09-01

    Histological studies of immature human permanent necrotic teeth with or without apical periodontitis after revascularization have not been reported. This case report describes the histological findings of tissue formed in the canal space of an immature permanent tooth #9 with irreversible pulpitis without apical periodontitis after revascularization. An immature human permanent tooth #9 was fractured 3.5 weeks after revascularization and could not be retained. The tooth was extracted and prepared for routine histological and immunohistochemical evaluation in order to examine the nature of tissue formed in the root canal following the revascularization procedure. At 3.5 weeks after revascularization, more than one half of the canal was filled with loose connective tissue similar to the pulp tissue. A layer of flattened odontoblast-like cells lined along the predentin. Layers of epithelial-like cells, similar to the Hertwig's epithelial root sheath, surrounded the root apex. No hard tissue was formed in the canal. Based on the histological findings in the present case, regeneration of pulp-like tissue is possible after revascularization. In this case, both the apical papilla and the Hertwig's epithelial root sheath survived in an immature permanent tooth despite irreversible pulpitis but without apical periodontitis. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Irreversibility of Asymptotic Entanglement Manipulation Under Quantum Operations Completely Preserving Positivity of Partial Transpose

    Science.gov (United States)

    Wang, Xin; Duan, Runyao

    2017-11-01

    We demonstrate the irreversibility of asymptotic entanglement manipulation under quantum operations that completely preserve the positivity of partial transpose (PPT), resolving a major open problem in quantum information theory. Our key tool is a new efficiently computable additive lower bound for the asymptotic relative entropy of entanglement with respect to PPT states, which can be used to evaluate the entanglement cost under local operations and classical communication (LOCC). We find that for any rank-two mixed state supporting on the 3 ⊗3 antisymmetric subspace, the amount of distillable entanglement by PPT operations is strictly smaller than one entanglement bit (ebit) while its entanglement cost under PPT operations is exactly one ebit. As a by-product, we find that for this class of states, both the Rains's bound and its regularization are strictly less than the asymptotic relative entropy of entanglement. So, in general, there is no unique entanglement measure for the manipulation of entanglement by PPT operations. We further show a computable sufficient condition for the irreversibility of entanglement distillation by LOCC (or PPT) operations.

  8. Study of the anesthetic efficacy of inferior alveolar nerve block using articaine in irreversible pulpitis.

    Science.gov (United States)

    Ahmad, Zeeshan H; Ravikumar, H; Karale, Rupali; Preethanath, R S; Sukumaran, Anil

    2014-01-01

    The purpose of this study was to determine the anesthetic efficacy of inferior alveolar nerve block (IANB) using 4% articaine and 2% lidocaine supplemented with buccal infiltration. Forty five patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth were included in the study. The first group of 15 patients received 2% lidocaine with 1:200000 epinephrine, the second group 2% lidocaine with 1: 80,000 epinephrine and the third group of 15 subjects received 4% articaine with 1:100000 epinephrine. During the access cavity preparation those patients who complained of pain received an additional buccal infiltration. The percentage of subjects who got profound anesthesia and failure to achieve anesthesia were calculated and tabulated using a visual analog scale. The results revealed that 87% of subjects who received 4% Articaine with 1:100,000 epinephrine got satisfactory anesthesia with inferior alveolar nerve block alone. Only 2 (13%) subjects received an additional buccal infiltration and none of the patients failed to obtain complete anesthesia with articaine. In comparison only 40% of subjects got complete anesthesia with 2% lidocaine with 1:200000 and 60% with 2% lidocaine with 1:80,000. It can be concluded that 4% articaine can be used effectively for obtaining profound anesthesia for endodontic procedures in patients with irreversible pulpitis.

  9. Putative Stem Cells in Human Dental Pulp with Irreversible Pulpitis-An Exploratory Study

    Science.gov (United States)

    Wang, Z.; Pan, J.; Wright, JT; Bencharit, S.; Zhang, S.; Everett, ET; Teixeira, FB; Preisser, JS

    2010-01-01

    Introduction Although human dental pulp stem cells isolated from healthy teeth have been extensively characterized, it is unknown whether stem cells also exist in clinically compromised teeth with irreversible pulpitis. Here we explored whether cells retrieved from clinically compromised dental pulp have stem cell-like properties. Methods Pulp cells were isolated from healthy teeth (control group) and from teeth with clinically diagnosed irreversible pulpitis (diseased group). Cell proliferation, stem cell marker STRO-1 expression and cell odonto-osteo-genic differentiation competence were compared. Results Cells from the diseased group demonstrated decreased colony formation capacity and a slightly decreased cell proliferation rate but had similar STRO-1 expression, and exhibited a similar percentage of positive ex vivo osteogenic induction and dentin sialophosphoprotein expression from STRO-1-enriched pulp cells. Conclusion Our study provides preliminary evidence that clinically compromised dental pulp may contain putative cells with certain stem cell properties. Further characterization of these cells will provide insight regarding whether they could serve as a source of endogenous multipotent cells in tissue regeneration based dental pulp therapy. PMID:20416426

  10. Thermally Reversible and Irreversible Phase Transition Behaviors in Poly(ethylene oxide)/Ionic Liquid Mixtures.

    Science.gov (United States)

    Chen, Yunlei; Niu, Yanhua; Gong, Pengjian; Xiao, Zhilin; Li, Guangxian

    2017-12-01

    The irreversible and reversible phase transition behaviors during phase separation-recovery (heating-cooling) cycles for poly(ethylene oxide)/1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (PEO/[EMIM][BF 4 ]) mixtures with a lower critical solution temperature phase diagram are reported for the first time. The evident differential scanning calorimetry endothermic and exothermic peaks are observed during the heating-cooling scan cycles near the phase boundary, in which the large heat loss for samples below the critical composition (60 wt% PEO) and obvious downward shift of phase transition temperature for all the compositions between the first and second cycles are particularly attractive. After the first recovery process, a reversible behavior during the next cycles is expected. These interesting phenomena are further confirmed by optical microscopy and Fourier-transform infrared measurements. It is demonstrated that the disruption and partial recovery of the hydrogen bonds, combined with the conformational change of PEO chains, can contribute to this irreversible behavior as well as a conversion to reversible phase transition behavior. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    International Nuclear Information System (INIS)

    Wang Hongyue; Zhao Lingling; Zhou Qiangtai; Xu Zhigao; Kim, Hyung Taek

    2008-01-01

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters

  12. Irreversible Aspects of Continuum Mechanics and Transfer of Physical Characteristics in Moving Fluids : Symposia

    CERN Document Server

    Sedov, L

    1968-01-01

    At its meeting on April 23, 1965 in Paris the Bureau of IUTAM decided to have a Symposium on the Irreversible Aspects of Continaum Mechanics held in June 1966 in Vienna. In addition, a Symposium on the Transfer of Physical Characteristics in Moving Fluids which, orig­ inally, had been scheduled to take place in Stockholm was rescheduled to be held in Vienna immediately following the Symposium on the Irre­ versible Aspects of Continuum Mechanics. It was felt that the subjects of the two symposia were so closely related that participants should be given an opportunity to attend both. Both decisions were unanimously approved by the members of the General Assembly of IUTAM. Prof. H. PARKUS, Vienna, was appointed Chairman of the Symposium on the Irreversible Aspects, and Prof. L. I. SEDOV, Moscow, was appointed Chairman of the Symposium on the Transfer of Physical Characteristics, with Prof. P ARKUS being re­ sponsible for the local organization of both symposia. In accordance with the policy set forth by IUTAM...

  13. Irreversible subacute sclerotic combined degeneration of the spinal cord in a vegan subject.

    Science.gov (United States)

    Brocadello, Filippo; Levedianos, Giorgio; Piccione, Francesco; Manara, Renzo; Pesenti, Francesco Francini

    2007-01-01

    We describe a case of irreversible subacute sclerotic combined degeneration of the spinal cord in a Western vegan subject. A 57-y-old man, member of a vegan cult for 13 y, developed weakness, paraplegia, hyper-reflexia, distal symmetric muscular hypotrophy, impairment of superficial sensation in the hands and feet, loss of deep sensation in the lower limbs, and neurogenic bladder and bowel. Magnetic resonance imaging of the cervical and dorsal spine disclosed abnormally increased signal intensity on T(2)-weighted sections in the posterior and lateral columns. Subacute sclerotic combined degeneration of the spinal cord was diagnosed and treatment with cobalamin was started. Despite rehabilitative treatment, the patient developed spastic hypertonia with mild improvement of paresthesias. Six months later, vitamin B12 plasma levels and hematological analysis were normal. One year later, spastic paraplegia was still present and the patient was unable to walk despite improvement on magnetic resonance imaging. Irreversible subacute sclerotic combined degeneration of the spinal cord is a rare but possible effect of a strict vegetarian diet.

  14. Changes in gastric mucosa, submucosa, and muscularis IC pH may herald irreversible tissue injury.

    Science.gov (United States)

    Fisher, Elaine M; Chiu, Sheau Huey; LaManna, Joseph C

    2013-01-01

    Previously we noted an abrupt rise in gastric intracellular pH (IC pH) and bicarbonate buffering between 15 and 30 min of cardiac arrest which we termed agonal alkalinization, failure of pH regulation. Agonal alkalinization may represent the transition point between reversible and irreversible injury. We asked the question, what is the sequence of change in IC pH within the gastric layers, mucosa, submucosa, and muscularis, and which layer is most sensitive? This research explored changes in IC pH within the stomach layers, mucosa, submucosa, and muscularis, at 0, 5, 15, 30, and 40 min, under three conditions, normoxia (control), ischemia (cardiac arrest), and eucapnic hypoxia (12 % oxygen). The mucosa was the most alkalotic gastric layer at baseline. Ischemia and hypoxia at 40″ produced different layer responses with the mucosa and submucosa the most sensitive layers during ischemia and the muscularis during hypoxia. Further study to examine the mechanism of changes between gastric layers using spatial-temporal techniques may assist in understanding the transition to irreversible injury.

  15. Formulation and Evaluation of CTRW Governing Equations for Irreversible, Bimolecular Reactions During Transport

    Science.gov (United States)

    Hansen, S. K.; Berkowitz, B.

    2014-12-01

    The continuous time random walk (CTRW) formalism is a valuable tool for modeling both conservative and reversibly sorbing solute transport in heterogeneous porous media, underpinning both Eulerian (integrodifferential equation-based) and Lagrangian (particle tracking) approaches to transport modeling. More recently, there has been interest in modeling transport with irreversible reactions, and Lagrangian CTRW-based numerical models have been successfully applied to these problems. However, a corresponding Eulerian theory has been lacking. We recently developed Eulerian governing equations in the presence of irreversible bimolecular reactions, via the device of upscaling transport and treating reactions at a finer scale. The technique is generally valid, even in porous media that do not have an obvious division of length scales, subject to certain smoothness assumptions on the solution. We show that the governing equations we develop simplify, under appropriate circumstances, to both the generalized master equation for the unreactive CTRW and to the advection-dispersion-reaction equation. We also present a numerical corroboration of our development and its underlying smoothness assumptions obtained using a novel, indirect particle-tracking / partial differential equation hybrid technique. We discuss the implications of the new governing equations for practical reactive transport modeling and for conceptualization of subsurface processes, and highlight connections to other approaches. As applicable, we will also discuss aspects of numerical implementation.

  16. Performance optimum analysis of an irreversible molten carbonate fuel cell–Stirling heat engine hybrid system

    International Nuclear Information System (INIS)

    Chen, Liwei; Zhang, Houcheng; Gao, Songhua; Yan, Huixian

    2014-01-01

    A new hybrid system mainly consists of a molten carbonate fuel cell (MCFC) and a Stirling heat engine is established, where the Stirling heat engine is driven by the high-quality waste heat generated in the MCFC. Based on the electrochemistry and non-equilibrium thermodynamics, analytical expressions for the efficiency and power output of the hybrid system are derived by taking various irreversible losses into account. It shows that the performance of the MCFC can be greatly enhanced by coupling a Stirling heat engine to further convert the waste heat for power generation. By employing numerical calculations, not only the influences of multiple irreversible losses on the performance of the hybrid system are analyzed, but also the impacts of some operating conditions such as the operating temperature, input gas compositions and operating pressure on the performance of the hybrid system are also discussed. The investigation method in the present paper is feasible for some other similar energy conversion systems as well. - Highlights: • A model of MCFC–Stirling heat engine hybrid system is established. • Analytical expressions for the efficiency and power output are derived. • MCFC performance can be greatly enhanced by coupling a Stirling heat engine. • Effects of some operating conditions on the performance are discussed. • Optimum operation regions are subdivided by multi-objective optimization method

  17. Phenylthiomethyl Ketone-Based Fragments Show Selective and Irreversible Inhibition of Enteroviral 3C Proteases.

    Science.gov (United States)

    Schulz, Robert; Atef, Amira; Becker, Daniel; Gottschalk, Franziska; Tauber, Carolin; Wagner, Stefan; Arkona, Christoph; Abdel-Hafez, Atef A; Farag, Hassan H; Rademann, Jörg; Wolber, Gerhard

    2018-02-08

    Lead structure discovery mainly focuses on the identification of noncovalently binding ligands. Covalent linkage, however, is an essential binding mechanism for a multitude of successfully marketed drugs, although discovered by serendipity in most cases. We present a concept for the design of fragments covalently binding to proteases. Covalent linkage enables fragment binding unrelated to affinity to shallow protein binding sites and at the same time allows differentiated targeted hit verification and binding location verification through mass spectrometry. We describe a systematic and rational computational approach for the identification of covalently binding fragments from compound collections inhibiting enteroviral 3C protease, a target with high therapeutic potential. By implementing reactive groups potentially forming covalent bonds as a chemical feature in our 3D pharmacophore methodology, covalent binders were discovered by high-throughput virtual screening. We present careful experimental validation of the virtual hits using enzymatic assays and mass spectrometry unraveling a novel, previously unknown irreversible inhibition of the 3C protease by phenylthiomethyl ketone-based fragments. Subsequent synthetic optimization through fragment growing and reactivity analysis against catalytic and noncatalytic cysteines revealed specific irreversible 3C protease inhibition.

  18. Kinetics of irreversible thermal decomposition of dissociating nitrogen dioxide with nitrogen oxide or oxygen additions

    International Nuclear Information System (INIS)

    Gvozdev, A.A.

    1987-01-01

    The effect of NO or O 2 admixtures on kinetics of the irreversible thermal decomposition of nitrogen dioxide at temperatures 460-520 deg C and pressures 4-7 MPa has been studied. It follows from experimental data that the rate of N 2 O 4 formation reduces with the increase of partial pressure of oxygen or decrease of partial pressure of nitrogen oxide. The same regularity is seen for the rate of nitrogen formation. The rate constants of N 2 O formation in dissociating nitrogen tetroxide with oxygen or nitrogen oxide additions agree satisfactorily with previously published results, obtained in stoichiometric mixtures. The appreciable discrepancy at 520 deg C is bind with considerable degree of nitrogen oxide transformation which constitutes approximately 14%. It is determined that the kinetics of formation of the products of irreversible N 2 O and N 2 decomposition in stoichiometric and non-stoichiometric 2NO 2 ↔ 2NO+O 2 mixtures is described by identical 3NO → N 2 O+NO 2 and N 2 O+NO → N 2 +NO 2 reactions

  19. On the existence of physiological age based on functional hierarchy: a formal definition related to time irreversibility.

    Science.gov (United States)

    Chauvet, Gilbert A

    2006-09-01

    The present approach of aging and time irreversibility is a consequence of the theory of functional organization that I have developed and presented over recent years (see e.g., Ref. 11). It is based on the effect of physically small and numerous perturbations known as fluctuations, of structural units on the dynamics of the biological system during its adult life. Being a highly regulated biological system, a simple realistic hypothesis, the time-optimum regulation between the levels of organization, leads to the existence of an internal age for the biological system, and time-irreversibility associated with aging. Thus, although specific genes are controlling aging, time-irreversibility of the system may be shown to be due to the degradation of physiological functions. In other words, I suggest that for a biological system, the nature of time is specific and is an expression of the highly regulated integration. An internal physiological age reflects the irreversible course of a living organism towards death because of the irreversible course of physiological functions towards dysfunction, due to the irreversible changes in the regulatory processes. Following the works of Prigogine and his colleagues in physics, and more generally in the field of non-integrable dynamical systems (theorem of Poincaré-Misra), I have stated this problem in terms of the relationship between the macroscopic irreversibility of the functional organization and the basic mechanisms of regulation at the lowest "microscopic" level, i.e., the molecular, lowest level of organization. The neuron-neuron elementary functional interaction is proposed as an illustration of the method to define aging in the nervous system.

  20. Pasos por la salud

    OpenAIRE

    Fierro Rojas, Carlos

    2013-01-01

    Pasos por la Salud surge como un proyecto (mismo que derivara una estrategia de atención) que establece el Departamento de Educación Física Valle de México, para fortalecer la aplicación del programa de Educación Física en Educación Básica, fomentará la práctica del ejercicio físico hacia la promoción de la salud, brindará a los alumnos elementos teóricos y bases metodológicas que le ayuden a comprender los beneficios de salud que producen la práctica del ejercicio, concientizar al alumno de ...

  1. Sepsis por shigella flexneri

    Directory of Open Access Journals (Sweden)

    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  2. Por uma arquitetura engajada

    Directory of Open Access Journals (Sweden)

    Maria Encarnação Beltrão Spósito

    2010-01-01

    Full Text Available A Arquitetura é vista, neste texto, como uma possibilidade de se compreender o mundo contemporâneo e, sobretudo, de repensá-lo, se queremos contribuir para a construção de um futuro com maior equidade, nele incluído o respeito às diferenças. Nessa perspectiva, uma Arquitetura engajada teria que considerar sempre o Urbanismo, no sentido de compreender a cidade, como nível de determinação do movimento da Sociedade e não apenas como um cenário em que múltiplas linguagens se expressem. Por seu caráter de ensaio, o texto tem mais o papel de levantar questões e estimular o debate, do que apresentar resultados ou respostas.

  3. Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

    International Nuclear Information System (INIS)

    Nelson, O.D.; Keller, G.M.

    1997-01-01

    This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

  4. Pilot Study to Assess Safety and Clinical Outcomes of Irreversible Electroporation for Partial Gland Ablation in Men with Prostate Cancer

    Science.gov (United States)

    Murray, Katie S.; Ehdaie, Behfar; Musser, John; Mashni, Joseph; Srimathveeravalli, Govindarajan; Durack, Jeremy C.; Solomon, Stephen B.; Coleman, Jonathan A.

    2016-01-01

    Purpose Partial prostate gland ablation is a strategy to manage localized prostate cancer. Irreversible electroporation can ablate localized soft tissues. We sought to describe 30- and 90-day complications and intermediate-term functional outcomes in men undergoing prostate gland ablation using irreversible electroporation. Materials and Methods We reviewed the charts of 25 patients with prostate cancer who underwent prostate gland ablation using irreversible electroporation as a primary procedure and who were followed for at least 6 months. Results Median follow-up was 10.9 months. Grade 3 complications occurred in 2 patients including epididymitis (1) and urinary tract infection (1). Fourteen patients experienced grade ≤ 2 complications, mainly transient urinary symptoms, hematuria, and urinary tract infections. Of 25 patients, 4 (16%) had cancer in the zone of ablation on routine follow-up biopsy at 6 months. Of those with normal urinary function at baseline, 88% and 94% reported normal urinary function at 6 and 12 months after prostate gland ablation, respectively. By 12 months, only 1 patient with normal erectile function at baseline reported new difficulty with potency and only 2 patients (8%) required a pad for urinary incontinence. Conclusions Prostate gland ablation with irreversible electroporation is feasible and safe in selected men with localized prostate cancer. Intermediate-term urinary and erectile function outcomes appear reasonable. Irreversible electroporation is effective in ablation of tumor-bearing prostate tissue, as a majority of men had no evidence of residual cancer on biopsy 6 months after prostate gland ablation. PMID:27113966

  5. Anesthetic efficacy of articaine for inferior alveolar nerve blocks in patients with symptomatic versus asymptomatic irreversible pulpitis.

    Science.gov (United States)

    Argueta-Figueroa, Liliana; Arzate-Sosa, Gabriel; Mendieta-Zeron, Hugo

    2012-01-01

    This study sought to determine the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine in patients with symptomatic and asymptomatic irreversible pulpitis in mandibular posterior teeth and if individual patient factors, pulpal disease characteristics, and previous medication are correlated to local anesthetic success. A second objective was to determine the specificity and sensibility of a cold test for prediction of anesthetic success prior to endodontic treatment. Seventy patients diagnosed with irreversible pulpitis in mandibular posterior teeth received 1.6 mL of 4% articaine with 1:100,000 epinephrine for an inferior alveolar nerve block (IANB) using a metal guide. The anesthetic solution was injected with a computer-preprogrammed delivery system for local anesthesia. Endodontic access was begun 15 minutes after solution deposition; later, patients rated their discomfort using the visual analog scale (VAS). The success rate for the IA NB using articaine was 64.2% in patients with symptomatic irreversible pulpitis and 86.9% in patients with asymptomatic irreversible pulpitis. Cold test prior to root canal treatment had a specificity and sensibility of 12.5% and 87.1%, respectively. The anesthetic efficacy of articaine in irreversible pulpitis is moderately acceptable, and anesthetic success increases when the patient has been premedicated with NSAIDs. The cold test appears to be a favorable indicator for predicting anesthetic success.

  6. Control Multivariable por Desacoplo

    Directory of Open Access Journals (Sweden)

    Fernando Morilla

    2013-01-01

    Full Text Available Resumen: La interacción entre variables es una característica inherente de los procesos multivariables, que dificulta su operación y el diseño de sus sistemas de control. Bajo el paradigma de Control por desacoplo se agrupan un conjunto de metodologías, que tradicionalmente han estado orientadas a eliminar o reducir la interacción, y que recientemente algunos investigadores han reorientado con objetivos de solucionar un problema tan complejo como es el control multivariable. Parte del material descrito en este artículo es bien conocido en el campo del control de procesos, pero la mayor parte de él son resultados de varios años de investigación de los autores en los que han primado la generalización del problema, la búsqueda de soluciones de fácil implementación y la combinación de bloques elementales de control PID. Esta conjunción de intereses provoca que no siempre se pueda conseguir un desacoplo perfecto, pero que sí se pueda conseguir una considerable reducción de la interacción en el nivel básico de la pirámide de control, en beneficio de otros sistemas de control que ocupan niveles jerárquicos superiores. El artículo resume todos los aspectos básicos del Control por desacoplo y su aplicación a dos procesos representativos: una planta experimental de cuatro tanques acoplados y un modelo 4×4 de un sistema experimental de calefacción, ventilación y aire acondicionado. Abstract: The interaction between variables is inherent in multivariable processes and this fact may complicate their operation and control system design. Under the paradigm of decoupling control, several methodologies that traditionally have been addressed to cancel or reduce the interactions are gathered. Recently, this approach has been reoriented by several researchers with the aim to solve such a complex problem as the multivariable control. Parts of the material in this work are well known in the process control field; however, most of them are

  7. An Exceptional Case of Complete Septate Uterus With Unilateral Cervical Aplasia (Class U2bC3V0/ESHRE/ESGE Classification) and Isolated Mullerian Remnants: Combined Hysteroscopic and Laparoscopic Treatment.

    Science.gov (United States)

    Di Spiezio Sardo, Attilio; Giampaolino, Pierluigi; Scognamiglio, Marianna; Varelli, Carlo; Nazzaro, Giovanni; Mansueto, Gelsomina; Nappi, Carmine; Grimbizis, Grigoris F

    2016-01-01

    To report the combined hysteroscopic and laparoscopic treatment of a complete septate uterus with unilateral cervical aplasia (class U2bC3V0/ESHRE/ESGE classification) and isolated mullerian remnants. Step-by-step presentation of the surgical treatment (Canadian Task Force classification 4). Complete septate uterus with unilateral cervical aplasia (formally Robert's uterus) is characterized by the presence of a uterine septum completely dividing the endometrial cavity into an obstructed hemicavity and a contralateral nonobstructing hemicavity connected normally to the existing cervix. It has always been described as isolated without any associated anomaly. A 30-year-old woman was referred to our department for dysmenorrhea and primary infertility. Hysterosalpingography showed the presence of a right (RT) hemiuterus with a patent fallopian tube; further evaluation with 2- and 3-dimensional ultrasound and magnetic resonance imaging showed an externally normal-appearing uterus, a right normal hemicavity connected normally with the existed cervix and, a left hemicavity fully divided from the right one by a complete septum and not connected with the cervix. Interestingly, a peculiar complex mass with cystic areas, attached posterolaterally from the left side to the uterine wall at the level of the isthmus and the upper cervix, was also diagnosed. The study protocol was approved by our local institutional review board. During outpatient hysteroscopy, a right uterine hemicavity with a single ostium was identified without any communication with the left hemicavity. The patient was then scheduled for combined laparoscopic and hysteroscopic treatment. During laparoscopy, a normal uterine body with multiple myomas and a pseudocystic lesion attached posteriorly and left laterally to the uterus at the level of the isthmus and the upper cervix were shown; no communication between the cystic part of that lesion and the isthmus or the cervicovaginal canal was observed. During

  8. The SAT Protein of Porcine Parvovirus Accelerates Viral Spreading through Induction of Irreversible Endoplasmic Reticulum Stress.

    Science.gov (United States)

    Mészáros, István; Tóth, Renáta; Olasz, Ferenc; Tijssen, Peter; Zádori, Zoltán

    2017-08-15

    The SAT protein (SATp) of porcine parvovirus (PPV) accumulates in the endoplasmic reticulum (ER), and SAT deletion induces the slow-spreading phenotype. The in vitro comparison of the wild-type Kresse strain and its SAT knockout (SAT - ) mutant revealed that prolonged cell integrity and late viral release are responsible for the slower spreading of the SAT - virus. During PPV infection, regardless of the presence or absence of SATp, the expression of downstream ER stress response proteins (Xbp1 and CHOP) was induced. However, in the absence of SATp, significant differences in the quantity and the localization of CHOP were detected, suggesting a role of SATp in the induction of irreversible ER stress in infected cells. The involvement of the induction of irreversible ER stress in porcine testis (PT) cell necrosis and viral egress was confirmed by treatment of infected cells by ER stress-inducing chemicals (MG132, dithiothreitol, and thapsigargin), which accelerated the egress and spreading of both the wild-type and the SAT - viruses. UV stress induction had no beneficial effect on PPV infection, underscoring the specificity of ER stress pathways in the process. However, induction of CHOP and its nuclear translocation cannot alone be responsible for the biological effect of SAT, since nuclear CHOP could not complement the lack of SAT in a coexpression experiment. IMPORTANCE SATp is encoded by an alternative open reading frame of the PPV genome. Earlier we showed that SATp of the attenuated PPV NADL-2 strain accumulates in the ER and accelerates virus release and spreading. Our present work revealed that slow spreading is a general feature of SAT - PPVs and is the consequence of prolonged cell integrity. PPV infection induced ER stress in infected cells regardless of the presence of SATp, as demonstrated by the morphological changes of the ER and expression of the stress response proteins Xbp1 and CHOP. However, the presence of SATp made the ER stress more severe and

  9. Irreversible inhibition of sodium current and batrachotoxin binding by a photoaffinity-derivatized local anesthetic.

    Science.gov (United States)

    McHugh, J; Mok, W M; Wang, G K; Strichartz, G

    1995-02-01

    We have synthesized a model local anesthetic (LA), N-(2-di-N-butyl-aminoethyl)-4-azidobenzamide (DNB-AB), containing the photoactivatable aryl azido moiety, which is known to form a covalent bond to adjacent molecules when exposed to UV light (Fleet, G.W., J.R. Knowles, and R.R. Porter. 1972. Biochemical Journal. 128:499-508. Ji, T.H. 1979. Biochimica et Biophysica Acta. 559:39-69). We studied the effects of DNB-AB on the sodium current (INa) under whole-cell voltage clamp in clonal mammalian GH3 cells and on 3[H]-BTX-B binding to sheep brain synaptoneurosomes. In the absence of UV illumination, DNB-AB behaved similarly to known LAs, producing both reversible block of peak INa (IC50 = 26 microM, 20 degrees C) and reversible inhibition of 3[H]-BTX-B (50 nM in the presence of 0.12 microgram/liter Leiurus quinquestriatus scorpion venom) binding (IC50 = 3.3 microM, 37 degrees C), implying a noncovalent association between DNB-AB and its receptor(s). After exposure to UV light, both block of INa and inhibition of 3[H]-BTX-B binding were only partially reversible (INa = 42% of control; 3[H]-BTX-B binding = 23% of control) showing evidence of a light-dependent, covalent association between DNB-AB and its receptor(s). In the absence of drug, UV light had less effect on INa (post exposure INa = 96% of control) or on 3[H]-BTX-B binding (post exposure binding = 70% of control). The irreversible block of INa was partially protected by coincubation of DNB-AB with 1 mM bupivacaine (IC50 = 45 microM, for INa inhibition at 20 degrees C, Wang, G.K., and S.Y. Wang. 1992. Journal of General Physiology. 100:1003-1020), (post exposure INa = 73% of control). The irreversible inhibition of 3[H]-BTX-B binding also was partially protected by coincubation with bupivacaine (500 microM, 37 degrees C) (post exposure binding = 51% of control), suggesting that the site of irreversible inhibition of both INa and 3[H]-BTX-B binding is shared with the clinical LA bupivacaine.

  10. A statistical model for multidimensional irreversible electroporation cell death in tissue

    Directory of Open Access Journals (Sweden)

    Rubinsky Boris

    2010-02-01

    Full Text Available Abstract Background Irreversible electroporation (IRE is a minimally invasive tissue ablation technique which utilizes electric pulses delivered by electrodes to a targeted area of tissue to produce high amplitude electric fields, thus inducing irreversible damage to the cell membrane lipid bilayer. An important application of this technique is for cancer tissue ablation. Mathematical modelling is considered important in IRE treatment planning. In the past, IRE mathematical modelling used a deterministic single value for the amplitude of the electric field required for causing cell death. However, tissue, particularly cancerous tissue, is comprised of a population of different cells of different sizes and orientations, which in conventional IRE are exposed to complex electric fields; therefore, using a deterministic single value is overly simplistic. Methods We introduce and describe a new methodology for evaluating IRE induced cell death in tissue. Our approach employs a statistical Peleg-Fermi model to correlate probability of cell death in heterogeneous tissue to the parameters of electroporation pulses such as the number of pulses, electric field amplitude and pulse length. For treatment planning, the Peleg-Fermi model is combined with a numerical solution of the multidimensional electric field equation cast in a dimensionless form. This is the first time in which this concept is used for evaluating IRE cell death in multidimensional situations. Results We illustrate the methodology using data reported in literature for prostate cancer cell death by IRE. We show how to fit this data to a Fermi function in order to calculate the critical statistic parameters. To illustrate the use of the methodology, we simulated 2-D irreversible electroporation protocols and produced 2-D maps of the statistical distribution of cell death in the treated region. These plots were compared to plots produced using a deterministic model of cell death by IRE and

  11. MRI study on reversible and irreversible electroporation induced blood brain barrier disruption.

    Directory of Open Access Journals (Sweden)

    Mohammad Hjouj

    Full Text Available Electroporation, is known to induce cell membrane permeabilization in the reversible (RE mode and cell death in the irreversible (IRE mode. Using an experimental system designed to produce a continuum of IRE followed by RE around a single electrode we used MRI to study the effects of electroporation on the brain. Fifty-four rats were injected with Gd-DOTA and treated with a G25 electrode implanted 5.5 mm deep into the striata. MRI was acquired immediately after treatment, 10 min, 20 min, 30 min, and up to three weeks following the treatment using: T1W, T2W, Gradient echo (GE, serial SPGR (DCE-MRI with flip angles ranging over 5-25°, and diffusion-weighted MRI (DWMRI. Blood brain barrier (BBB disruption was depicted as clear enhancement on T1W images. The average signal intensity in the regions of T1-enhancement, representing BBB disruption, increased from 1887±83 (arbitrary units immediately post treatment to 2246±94 20 min post treatment, then reached a plateau towards the 30 min scan where it reached 2289±87. DWMRI at 30 min showed no significant effects. Early treatment effects and late irreversible damage were clearly depicted on T2W. The enhancing volume on T2W has increased by an average of 2.27±0.27 in the first 24-48 hours post treatment, suggesting an inflammatory tissue response. The permanent tissue damage, depicted as an enhancing region on T2W, 3 weeks post treatment, decreased to an average of 50±10% of the T2W enhancing volumes on the day of the treatment which was 33±5% of the BBB disruption volume. Permanent tissue damage was significantly smaller than the volume of BBB disruption, suggesting, that BBB disruption is associated with RE while tissue damage with IRE. These results demonstrate the feasibility of applying reversible and irreversible electroporation for transient BBB disruption or permanent damage, respectively, and applying MRI for planning/monitoring disruption volume/shape by optimizing electrode positions

  12. Is ‘hit and run’ a single word? The processing of irreversible binomials in neglect dyslexia

    Directory of Open Access Journals (Sweden)

    Giorgio eArcara

    2012-02-01

    Full Text Available The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials, i.e. word pairs linked by a conjunction (e.g. ‘hit and run’, ‘dead or alive’. In order to test their lexical status, the phenomenon of neglect dyslexia is explored.People with left-sided neglect dyslexia show a clear lexical effect: they can read irreversible binomials better (i.e., by dropping the leftmost words less frequently when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that irreversible binomials tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  13. [Mineral trioxide aggragate pulpotomy for the treatment of immature permanent teeth with irreversible pulpitis: a preliminary clinical study].

    Science.gov (United States)

    Peng, Chufang; Zhao, Yuming; Yang, Yuan; Qin, Man

    2015-12-01

    To evaluate the preliminary clinical effect of mineral trioxide aggragate (MTA) pulpotomy on immature permanent teeth with irreversible pulpitis. Twenty-six immature permanent teeth with irreversible pulpitis were recuited from Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology. These teeth were treated with partial or full pulpotomy according to the condition of pulp bleeding. MTA was used as pulp capping material. Patients were recalled periodically after the treatment. Clinical and radiographic effects were evaluated. At one year follow-up, 20 teeth were evaluated as healed or healing, 2 teeth were evaluated as failure and 4 teeth were dropped out. The success rate was considered 91% (20/22). A dentinal bridge was radiographcally observed underneath the pulpotomy site in 13 teeth(65%, 13/20). MTA pulpotomy is an effective method for the treatment of immature permanent teeth with irreversible pulpitis. But further research with longer follow up period is required.

  14. Hair repigmentation associated with the use of lenalidomide: graying may not be an irreversible process!

    Science.gov (United States)

    Dasanu, Constantin A; Mitsis, Demytra; Alexandrescu, Doru T

    2013-06-01

    We report the first case of progressive hair repigmentation associated with the use of lenalidomide in an elderly patient with multiple myeloma. The influence of lenalidomide on follicular melanogenesis may involve removing the inhibitory influences of some cytokines such as IL-1, IL-6 and TNF-α. In addition, certain endocrine effects of lenalidomide on the hypophyseal-adrenal axis could explain its action on hair pigmentation. We further hypothesize that lenalidomide may be capable of stimulating migration and/or differentiation of melanocytes to promote repigmentation of gray hair follicles. Pending the clarification of how hair repigmentation occurs with lenalidomide, our observation materializes the concept that hair graying may not be an irreversible process, which opens avenues for targeted therapeutics in the fields of cosmetics and anti-aging medicine.

  15. Exploring the optimal performances of irreversible single resonance energy selective electron refrigerators

    Science.gov (United States)

    Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui

    2016-05-01

    Applying finite-time thermodynamics (FTT) and electronic transport theory, the optimal performances of irreversible single resonance energy selective electron (ESE) refrigerator are analyzed. The effects of heat leakage between two electron reservoirs on optimal performances are discussed. The influences of system operating parameters on cooling load, coefficient of performance (COP), figure of merit and ecological function are demonstrated using numerical examples. Comparative performance analyses among different objective functions show that performance characteristics at maximum ecological function and maximum figure of merit are of great practical significance. Combining the two optimization objectives of maximum ecological function and maximum figure of merit together, more specific optimal ranges of cooling load and COP are obtained. The results can provide some advices to the design of practical electronic machine systems.

  16. Is "hit and run" a single word? The processing of irreversible binomials in neglect dyslexia.

    Science.gov (United States)

    Arcara, Giorgio; Lacaita, Graziano; Mattaloni, Elisa; Passarini, Laura; Mondini, Sara; Benincà, Paola; Semenza, Carlo

    2012-01-01

    The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials (IBs), i.e., word pairs linked by a conjunction (e.g., "hit and run," "dead or alive"). In order to test their lexical status, the phenomenon of neglect dyslexia is explored. People with left-sided neglect dyslexia show a clear lexical effect: they can read IBs better (i.e., by dropping the leftmost words less frequently) when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that IBs tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  17. Irreversible particle motion in surfactant-laden interfaces due to pressure-dependent surface viscosity

    Science.gov (United States)

    Manikantan, Harishankar; Squires, Todd M.

    2017-09-01

    The surface shear viscosity of an insoluble surfactant monolayer often depends strongly on its surface pressure. Here, we show that a particle moving within a bounded monolayer breaks the kinematic reversibility of low-Reynolds-number flows. The Lorentz reciprocal theorem allows such irreversibilities to be computed without solving the full nonlinear equations, giving the leading-order contribution of surface pressure-dependent surface viscosity. In particular, we show that a disc translating or rotating near an interfacial boundary experiences a force in the direction perpendicular to that boundary. In unbounded monolayers, coupled modes of motion can also lead to non-intuitive trajectories, which we illustrate using an interfacial analogue of the Magnus effect. This perturbative approach can be extended to more complex geometries, and to two-dimensional suspensions more generally.

  18. Graphical Analysis of PET Data Applied to Reversible and Irreversible Tracers

    Energy Technology Data Exchange (ETDEWEB)

    Logan, Jean

    1999-11-18

    Graphical analysis refers to the transformation of multiple time measurements of plasma and tissue uptake data into a linear plot, the slope of which is related to the number of available tracer binding sites. This type of analysis allows easy comparisons among experiments. No particular model structure is assumed, however it is assumed that the tracer is given by bolus injection and that both tissue uptake and the plasma concentration of unchanged tracer are monitored following tracer injection. The requirement of plasma measurements can be eliminated in some cases when a reference region is available. There are two categories of graphical methods which apply to two general types of ligands--those which bind reversibly during the scanning procedure and those which are irreversible or trapped during the time of the scanning procedure.

  19. Irreversible altering of crystalline phase of phase-change Ge-Sb thin films

    International Nuclear Information System (INIS)

    Krusin-Elbaum, L.; Shakhvorostov, D.; Cabral, C. Jr.; Raoux, S.; Jordan-Sweet, J. L.

    2010-01-01

    The stability of the crystalline phase of binary phase-change Ge x Sb 1-x films is investigated over a wide range of Ge content. From Raman spectroscopy we find the Ge-Sb crystalline structure irreversibly altered after exposure to a laser beam. We show that with increasing beam intensity/temperature Ge agglomerates and precipitates out in the amount growing with x. A simple empirical relation links Ge precipitation temperature T Ge p to the rate of change dT cryst /dx of crystallization, with the precipitation easiest on the mid-range x plateau, where T cryst is nearly constant. Our findings point to a preferable 15% < or approx. x < 50% window, that may achieve the desired cycling/archival properties of a phase-change cell.

  20. Performance analysis for minimally nonlinear irreversible refrigerators at finite cooling power

    Science.gov (United States)

    Long, Rui; Liu, Zhichun; Liu, Wei

    2018-04-01

    The coefficient of performance (COP) for general refrigerators at finite cooling power have been systematically researched through the minimally nonlinear irreversible model, and its lower and upper bounds in different operating regions have been proposed. Under the tight coupling conditions, we have calculated the universal COP bounds under the χ figure of merit in different operating regions. When the refrigerator operates in the region with lower external flux, we obtained the general bounds (0 present large values, compared to a relative small loss from the maximum cooling power. If the cooling power is the main objective, it is desirable to operate the refrigerator at a slightly lower cooling power than at the maximum one, where a small loss in the cooling power induces a much larger COP enhancement.

  1. Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro

    International Nuclear Information System (INIS)

    Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

    1989-01-01

    Oxymorphazone was found to be a relatively weak antinociceptive drug in intact frog (Rana esculenta) when acetic acid was used as pain stimulus. Frogs remained analgesic for at least 48 hrs following oxymorphazone administration. The ligand increased the latency of wiping reflex in spinal frogs too. There effects were blocked by naloxone. In equilibrium binding studies ( 3 H)oxymorphazone had high affinity to the opioid receptors of frog brain and spinal cord as well. Kinetic experiments show that only 25% of the bound ( 3 H)oxymorphazone is readily dissociable. Preincubation of the membranes with labeled oxymorphazone results in a washing resistant inhibition of the opioid binding sites. At least 70% of the ( 3 H)oxymorphazone specific binding is apparently irreversible after reaction at 5 nM ligand concentration, and this can be enhanced by a higher concentration of tritiated ligand

  2. Strain induced irreversible critical current degradation in highly dense Bi-2212 round wire

    CERN Document Server

    Bjoerstad, R; Rikel, M.O.; Ballarino, A; Bottura, L; Jiang, J; Matras, M; Sugano, M; Hudspeth, J; Di Michiel, M

    2015-01-01

    The strain induced critical current degradation of overpressure processed straight Bi 2212/Ag wires has been studied at 77 K in self-field. For the first time superconducting properties, lattice distortions, composite wire stress and strain have been measured simultaneously in a high energy synchrotron beamline. A permanent Ic degradation of 5% occurs when the wire strain exceeds 0.60%. At a wire strain of about 0.65% a drastic n value and Ic reduction occur, and the composite stress and the Bi-2212 lattice parameter reach a plateau, indicating Bi-2212 filament fracturing. The XRD measurements show that Bi-2212 exhibits linear elastic behaviour up to the irreversible strain limit.

  3. Irreversibility line of an Ag-doped Hg-based superconductor

    International Nuclear Information System (INIS)

    Mostafa, M F; Hassen, A; Kunkel, H P

    2010-01-01

    The effect of doping with Ag of the bulk superconducting Hg 0.3 La 0.7 Ba 2 Ca 3 (Cu 1-x Ag x ) 4 O 10+δ , 0.1 ≤ x ≤ 0.3 phase (Hg-1234) is presented. The lattice parameter a = 3.824 A remains constant, while parameter c was found to increase from c = 19.0225 A (x = 0.0) to 19.08 A (x = 0.3) with the addition of Ag. The variation of T c versus the c-parameter exhibits a cupola-shaped behavior. The irreversibility line is thermally activated. The logarithmic plot of H irr versus (1 - T irr /T c (0)) shows a crossover temperature reflecting a transition from two- to three-dimensional behavior with increasing temperature. Fitting of the results to different models is discussed. Thermally activated de-pinning according to Matsushita's formula gives the best fit.

  4. Endodontic therapy of a mandibular canine tooth with irreversible pulpitis secondary to dentigerous cyst.

    Science.gov (United States)

    MacGee, Scott

    2014-01-01

    Dentigerous cysts are uncommon, yet are being reported with increasing frequency in the veterinary literature. Dentigerous cysts are a type of benign odontogenic cyst associated with impacted teeth, most commonly the mandibular first premolar tooth. Significant bone destruction can occur secondary to the expansion of a dentigerous cyst. The expanding cyst can lead to pathology of neighboring teeth, which can include external root resorption or pulpitis. Intraoral dental radiographs are imperative to properly assess the presence and extent of a dentigerous cyst, as well as the status of the neighboring teeth. This case report describes treatment for dentigerous cyst including cyst lining curettage, mandibular bone regeneration, and endodontic therapy for a canine tooth with irreversible pulpitis.

  5. Anesthetic success of supplemental infiltration in mandibular molars with irreversible pulpitis: A systematic review

    Science.gov (United States)

    Yadav, Seema

    2015-01-01

    Aim: To systematically review the anesthetic success rates of inferior alveolar nerve block (IANB) injection technique alone with that of combination of IANB and supplemental infiltration (SI) technique when used for pulpal anesthesia of mandibular posterior teeth with irreversible pulpitis during endodontic treatment. Settings and Design: The study follows a longitudinal study design involving original research. Materials and Methods: Electronic databases were systematically searched for randomized controlled clinical studies. Studies were selected by predefined inclusion and exclusion criteria. Statistical Analysis Used and Result: The statistical analysis used was based on the results of the original research. All the included studies showed that there is the difference in the values comparing the two techniques, but the data are not statistically significantly different. Conclusion: Based on this review, the better anesthetic efficacy of the SI was observed. PMID:26069400

  6. Antibiotics are not useful to reduce pain associated with irreversible pulpitis.

    Science.gov (United States)

    Hoskin, Eileen; Veitz-Keenan, Analia

    2016-09-01

    Data sourcesCochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Clinical Trials.gov and the WHO International Clinical Trials Registry Platform. There were no language restrictions.Study selectionRandomised controlled trials which compared the relief of pain with systemic antibiotics and analgesics against placebo and analgesics in the preoperative phase of irreversible pulpitis. The primary interest was pain control with an antibiotic or without one in the presence of analgesics. The secondary outcomes were type, dose and frequency of medication for pain relief and any adverse effects related to hypersensitivity or other reactions to either the antibiotic or analgesics.Data extraction and synthesisTwo authors independently assessed the results of the searches. Data extraction and risk bias assessment were also carried out independently. A third reviewer settled any disagreement on inclusion. Since only one study was included a meta-analysis could not be performed.ResultsOnly one double blind randomised clinical trial involving 40 participants with a diagnosis of irreversible pulpitis in one of their teeth was included in this review. This was a low risk, well-constructed double blind study. Half of the participants were treated with penicillin 500 mg, the other with a placebo every six hours over a seven- day period. In addition, all the participants were instructed to initially take one tablet of ibuprofen every 4-6 hours as needed and to take acetaminophen with codeine (two tablets every 4-6 hours) only if the ibuprofen did not relieve the pain.There was no significant difference in the mean total number of ibuprofen tablets over the study period; 9.2(standard deviation (SD) 6.02) in the penicillin group versus, 9.6 (SD 6.34) in the placebo group; mean difference -0.40 (95% CI -4.23 to 3.43); P value = 0.84.The mean total number of Tylenol tablets, 6.9 (SD 6.87), used in the penicillin group versus 4

  7. Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

    1989-01-01

    Oxymorphazone was found to be a relatively weak antinociceptive drug in intact frog (Rana esculenta) when acetic acid was used as pain stimulus. Frogs remained analgesic for at least 48 hrs following oxymorphazone administration. The ligand increased the latency of wiping reflex in spinal frogs too. There effects were blocked by naloxone. In equilibrium binding studies (/sup 3/H)oxymorphazone had high affinity to the opioid receptors of frog brain and spinal cord as well. Kinetic experiments show that only 25% of the bound (/sup 3/H)oxymorphazone is readily dissociable. Preincubation of the membranes with labeled oxymorphazone results in a washing resistant inhibition of the opioid binding sites. At least 70% of the (/sup 3/H)oxymorphazone specific binding is apparently irreversible after reaction at 5 nM ligand concentration, and this can be enhanced by a higher concentration of tritiated ligand.

  8. Fast X-ray microdiffraction techniques for studying irreversible transformations in materials.

    Science.gov (United States)

    Kelly, Stephen T; Trenkle, Jonathan C; Koerner, Lucas J; Barron, Sara C; Walker, Nöel; Pouliquen, Philippe O; Tate, Mark W; Gruner, Sol M; Dufresne, Eric M; Weihs, Timothy P; Hufnagel, Todd C

    2011-05-01

    A pair of techniques have been developed for performing time-resolved X-ray microdiffraction on irreversible phase transformations. In one technique capillary optics are used to focus a high-flux broad-spectrum X-ray beam to a 60 µm spot size and a fast pixel array detector is used to achieve temporal resolution of 55 µs. In the second technique the X-rays are focused with Kirkpatrick-Baez mirrors to achieve a spatial resolution better than 10 µm and a fast shutter is used to provide temporal resolution better than 20 µs while recording the diffraction pattern on a (relatively slow) X-ray CCD camera. Example data from experiments are presented where these techniques are used to study self-propagating high-temperature synthesis reactions in metal laminate foils.

  9. Irreversible Time Flow in a Two-Dimensional Dilaton Black Hole with Matter

    CERN Document Server

    Diamandis, G A; Georgalas, B C; Mavromatos, Nikolaos E; Nanopoulos, Dimitri V; Papantonopoulos, E; Ellis, John

    1998-01-01

    We show that an exact solution of two-dimensional dilaton gravity with matter discovered previously exhibits an irreversible temporal flow towards flat space with a vanishing cosmological constant. This time flow is induced by the back reaction of matter on the space-time geometry. We demonstrate that the system is not in equilibrium if the cosmological constant is non-zero, whereas the solution with zero cosmological constant is stable. The flow of the system towards this stable end-point is derived from the renormalization-group flow of the Zamolodchikov function. This behaviour is interpreted in terms of non-critical Liouville string, with the Liouville field identified as the target time.

  10. Electric fields control the orientation of peptides irreversibly immobilized on radical-functionalized surfaces.

    Science.gov (United States)

    Martin, Lewis J; Akhavan, Behnam; Bilek, Marcela M M

    2018-01-24

    Surface functionalization of an implantable device with bioactive molecules can overcome adverse biological responses by promoting specific local tissue integration. Bioactive peptides have advantages over larger protein molecules due to their robustness and sterilizability. Their relatively small size presents opportunities to control the peptide orientation on approach to a surface to achieve favourable presentation of bioactive motifs. Here we demonstrate control of the orientation of surface-bound peptides by tuning electric fields at the surface during immobilization. Guided by computational simulations, a peptide with a linear conformation in solution is designed. Electric fields are used to control the peptide approach towards a radical-functionalized surface. Spontaneous, irreversible immobilization is achieved when the peptide makes contact with the surface. Our findings show that control of both peptide orientation and surface concentration is achieved simply by varying the solution pH or by applying an electric field as delivered by a small battery.

  11. Surface and bulk modified high capacity layered oxide cathodes with low irreversible capacity loss

    Science.gov (United States)

    Manthiram, Arumugam (Inventor); Wu, Yan (Inventor)

    2010-01-01

    The present invention includes compositions, surface and bulk modifications, and methods of making of (1-x)Li[Li.sub.1/3Mn.sub.2/3]O.sub.2.xLi[Mn.sub.0.5-yNi.sub.0.5-yCo.sub.2- y]O.sub.2 cathode materials having an O3 crystal structure with a x value between 0 and 1 and y value between 0 and 0.5, reducing the irreversible capacity loss in the first cycle by surface modification with oxides and bulk modification with cationic and anionic substitutions, and increasing the reversible capacity to close to the theoretical value of insertion/extraction of one lithium per transition metal ion (250-300 mAh/g).

  12. Irreversible electroporation of locally advanced solid pseudopapillary carcinoma of the pancreas: A case report

    Directory of Open Access Journals (Sweden)

    Luciano Tarantino

    2018-04-01

    Full Text Available Introduction: Solid pseudopapillary Carcinoma (SPC is a rare pancreatic Tumor with variable, usually low, malignancy potential. Howewer, several SPC are associated with aggressive behavior, local vascular infiltration, organ invasion, distant metastasis, and can be unresectable. Irreversible Electroporation (IRE is an emerging non-thermal ablation technique for the treatment of locally advanced pancreatic carcinoma. We report the results of four year disease-free follow-up in a case of locally advanced unresectable SPC treated with IRE. Presentation of case: A 24-year female patient with SPC of the pancreas underwent IRE during laparotomy under general anesthesia with intubation. Computed Tomography (CT showed complete tumor thrombosis of splenic vein, encasement of celiac artery and mesenteric vein. Six insertions of 3–4 electrodes per insertion were performed. One month-CT-control showed shrinkage of the tumor. 6 months-post-treatment imaging showed complete regression of the mass, patent Splenic/mesenteric veins, absence of local recurrence or distant metastasis. Post treatment CTs at 12-18-24-30-36-42-48 months follow-up confirmed absence of local or distant recurrence. Discussion: Surgery is the first choice curative treatment of SPC. Howewer aggressive surgery (duodeno-pancreasectomy in unresectable cases, may have a high risk of recurrences, morbidities and death, and bring concerns about endocrine and exocrine insufficiency in a young patient. In these cases, IRE could be a safe and effective alternative treatment and could realize, in selected cases, the condition for a radical surgery, and a bridge to R-0 resection. Conclusions: IRE could represent an effective alternative therapy to surgery in local advanced, unresectable SPC. Keywords: Pancreatic neoplasm, Solid papillary carcinoma, Intraoperative ultrasound, Irreversible electroporation, Case report

  13. Reversible and irreversible vascular bioeffects induced by ultrasound and microbubbles in chorioallantoic membrane model

    Science.gov (United States)

    Tarapacki, Christine; Kuebler, Wolfgang M.; Tabuchi, Arata; Karshafian, Raffi

    2017-03-01

    Background: The application of ultrasound and microbubbles at therapeutic conditions has been shown to improve delivery of molecules, cause vasoconstriction, modulate blood flow and induce a vascular shut down in in vivo cancerous tissues. The underlying mechanism has been associated with the interaction of ultrasonically-induced microbubble oscillation and cavitation with the blood vessel wall. In this study, the effect of ultrasound and microbubbles on blood flow and vascular architecture was studied using a fertilized chicken egg CAM (chorioallantoic membrane) model. Methods: CAM at day 12 of incubation (Hamburger-Hamilton stage 38-40) were exposed to ultrasound at varying acoustic pressures (160, 240 and 320 kPa peak negative pressure) in the presence of Definity microbubbles and 70 kDa FITC dextran fluorescent molecules. A volume of 50 µL Definity microbubbles were injected into a large anterior vein of the CAM prior to ultrasound exposure. The ultrasound treatment sequence consisted of 5 s exposure at 500 kHz frequency, 8 cycles and 1 kHz pulse repetition frequency with 5 s off for a total exposure of 2 minutes. Fluorescent videos and images of the CAM vasculature were acquired using intravital microscopy prior, during and following the ultrasound exposure. Perfusion was quantified by measuring the length of capillaries in a region of interest using Adobe Illustrator. Results and Discussion: The vascular bioeffects induced by USMB increased with acoustic peak negative pressure. At 160 kPa, no visible differences were observed compared to the control. At 240 kPa, a transient decrease in perfusion with subsequent recovery within 15 minutes was observed, whereas at 320 kPa, the fluorescent images showed an irreversible vascular damage. The study indicates that a potential mechanism for the transient decrease in perfusion may be related to blood coagulation. The results suggest that ultrasound and microbubbles can induce reversible and irreversible vascular

  14. A facile route for irreversible bonding of plastic-PDMS hybrid microdevices at room temperature.

    Science.gov (United States)

    Tang, Linzhi; Lee, Nae Yoon

    2010-05-21

    Plastic materials do not generally form irreversible bonds with poly(dimethylsiloxane) (PDMS) regardless of oxygen plasma treatment and a subsequent thermal process. In this paper, we perform plastic-PDMS bonding at room temperature, mediated by the formation of a chemically robust amine-epoxy bond at the interfaces. Various plastic materials, such as poly(methylmethacrylate) (PMMA), polycarbonate (PC), polyimide (PI), and poly(ethylene terephthalate) (PET) were adopted as choices for plastic materials. Irrespective of the plastic materials used, the surfaces were successfully modified with amine and epoxy functionalities, confirmed by the surface characterizations such as water contact angle measurements and X-ray photoelectron spectroscopy (XPS), and chemically robust and irreversible bonding was successfully achieved within 1 h at room temperature. The bonding strengths of PDMS with PMMA and PC sheets were measured to be 180 and 178 kPa, respectively, and their assemblies containing microchannel structures endured up to 74 and 84 psi (510 and 579 kPa) of introduced compressed air, respectively, without destroying the microdevices, representing a robust and highly stable interfacial bonding. In addition to microchannel-molded PDMS bonded with flat plastic substrates, microchannel-embossed plastics were also bonded with a flat PDMS sheet, and both types of bonded assemblies displayed sufficiently robust bonding, tolerating an intense influx of liquid whose per-minute injection volume was nearly 1000 to 2000 times higher than the total internal volume of the microchannel used. In addition to observing the bonding performance, we also investigated the potential of surface amine and epoxy functionalities as durable chemical adhesives by observing their storage-time-dependent bonding performances.

  15. Psychologic adjustment to irreversible vision loss in adults: a systematic review.

    Science.gov (United States)

    Senra, Hugo; Barbosa, Fernando; Ferreira, Patrícia; Vieira, Cristina R; Perrin, Paul B; Rogers, Heather; Rivera, Diego; Leal, Isabel

    2015-04-01

    To summarize relevant evidence investigating the psychologic adjustment to irreversible vision loss (IVL) in adults. Irreversible vision loss entails a challenging medical condition in which rehabilitation outcomes are strongly dependent on the patient's psychologic adjustment to illness and impairment. So far, no study has systematically reviewed the psychologic adjustment to IVL in adults. We reviewed all articles examining the psychologic adjustment to IVL in adults. We included articles published in English in peer-reviewed journals. We performed a keyword literature search using 4 databases (PubMed, EBSCO, Cochrane Library, and Science Direct) for all years through July 2014. We assessed risk of bias of selected studies using the RTI Item Bank for Assessing Risk of Bias and Confounding for Observational Studies of Interventions or Exposures and the Cochrane risk of bias tool for randomized controlled trials. Of a total of 3948 citations retrieved, we selected 52 eligible studies published between 1946 and 2014. The majority of studies were observational and cross-sectional in nature. Our review suggests that high levels of depression occur during the adjustment to IVL. Better adjustment to IVL was associated with greater acceptance of vision loss and use of instrumental coping, good social support, positivity, and use of assistive aids. The overall findings indicate that IVL often has negative effects on patients' quality of life and mental health and that such effects tend to remain over time. Specific factors and variables associated with the adjustment to IVL need to be clarified through further in-depth and longitudinal research. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  16. Selective and irreversible inhibitors of aphid acetylcholinesterases: steps toward human-safe insecticides.

    Directory of Open Access Journals (Sweden)

    Yuan-Ping Pang

    Full Text Available Aphids, among the most destructive insects to world agriculture, are mainly controlled by organophosphate insecticides that disable the catalytic serine residue of acetylcholinesterase (AChE. Because these agents also affect vertebrate AChEs, they are toxic to non-target species including humans and birds. We previously reported that a cysteine residue (Cys, found at the AChE active site in aphids and other insects but not mammals, might serve as a target for insect-selective pesticides. However, aphids have two different AChEs (termed AP and AO, and only AP-AChE carries the unique Cys. The absence of the active-site Cys in AO-AChE might raise concerns about the utility of targeting that residue. Herein we report the development of a methanethiosulfonate-containing small molecule that, at 6.0 microM, irreversibly inhibits 99% of all AChE activity extracted from the greenbug aphid (Schizaphis graminum without any measurable inhibition of the human AChE. Reactivation studies using beta-mercaptoethanol confirm that the irreversible inhibition resulted from the conjugation of the inhibitor to the unique Cys. These results suggest that AO-AChE does not contribute significantly to the overall AChE activity in aphids, thus offering new insight into the relative functional importance of the two insect AChEs. More importantly, by demonstrating that the Cys-targeting inhibitor can abolish AChE activity in aphids, we can conclude that the unique Cys may be a viable target for species-selective agents to control aphids without causing human toxicity and resistance problems.

  17. Irreversible Total Loss of Brain Function and Organ Donation in Patients with Aneurysmal Subarachnoid Hemorrhage.

    Science.gov (United States)

    Mohme, Malte; Sauvigny, Thomas; Grensemann, Jörn; Söffker, Gerold; Kluge, Stefan; Westphal, Manfred; Czorlich, Patrick

    2017-09-01

    Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening disease with an often fatal clinical course leading to irreversible loss of brain function (ILBF) (i.e., brain death). The purpose of this study was to assess the prevalence and characteristics of patients with aSAH who became organ donors after diagnosis of ILBF. Anonymized clinical data sets of 395 patients treated for aSAH at a university medical center from January 2011 to December 2016 were retrospectively analyzed. Prevalence of consent for organ donation and clinical characteristics, including parameters for diagnosis of irreversible loss of brain function, were assessed. After initial admission to the intensive care unit, 18.0% of patients (n = 71) died (Glasgow Outcome Scale score 1). Intracerebral hemorrhage occurred in 42.3% of patients who died, aneurysmal rebleeding occurred in 19.7%, and intraventricular hemorrhage occurred in 87.3%. In 50.7% of patients who died (n = 36), ILBF was diagnosed, and 32.4% (n = 23) of these patients became organ donors. In 55.6%, additional diagnostic electroencephalography was performed. Male patients significantly more often became organ donors than female patients (P = 0.008). ILBF with subsequent organ donation was predominantly seen in patients organs were explanted for donation, including 42 kidneys, 21 livers, 3 pancreas, 11 hearts and 8 lungs. ILBF in the setting of fatal aSAH is a prevalent diagnosis with complex demands for neurointensive care physicians. We demonstrated the clinical characteristics and epidemiologic factors of patients with aSAH converting to organ donors. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Water and salt dynamics and the hydraulic conductivity feedback: irreversible soil degradation and reclamation opportunities

    Science.gov (United States)

    Mau, Yair; Porporato, Amilcare

    2017-04-01

    We present a model for the dynamics of soil water, salt concentration and exchangeable sodium fraction in the root zone, driven by irrigation water of various qualities and stochastic rainfall. The main nonlinear feedback is the decrease in hydraulic conductivity for low salinity and/or high sodicity levels. The three variables have quite disparate characteristic time scales: soil water can vary two or three orders of magnitude faster than the exchangeable sodium fraction. In certain limiting cases in which the input of water is constant, the system can be simplified by eliminating the equation for soil water, allowing a full description of the dynamics in the two-dimensional salinity-sodicity phase space. We estimate soil structure degradation time scales for high sodium-adsorption-ratio irrigation water, and delineate the regions in the salinity-sodicity phase space where sodium-induced degradation is effectively irreversible. This apparent irreversibility is the result of relatively long evolution time scales with respect to human activity. When we take into account stochastic rainfall—and the accompanying wetting and drying cycles—the system produces a myriad of statistical steady states. This means that equal environmental conditions can produce different outcomes, accessible to each other only by large interventions, such as temporary changes in the quality of irrigation water or one-time amendment use. Our characterization of the dynamics of water and salt in the root zone, and how it depends on environmental parameters, offers us opportunities to control and reclaim degraded states making optimal resource use. We show an example of sodic soil reclamation through calcium-based fertigation, with minimal time (and applied water) expenditure.

  19. Morbidade na criança e lesões irreversíveis ocasionadas por material de limpeza Children morbidity and irreversible injury caused by cleaning material

    Directory of Open Access Journals (Sweden)

    Sarah Anna Macieira

    2001-06-01

    Full Text Available O presente trabalho tem como objetivo relatar um estudo de caso desenvolvido com uma criança desnutrida, de 6 anos, do sexo feminino, com estenose de esôfago. Como estratégia metodológica realizamos a coleta de dados através de estudo em prontuário médico e visita domiciliar. Observamos a falta de percepção da família sobre os riscos dos produtos de limpeza ao alcance da criança; a necessidade de acompanhamento da equipe de saúde (enfermeiro, psicólogo, médico, assistente social e nutricionista, cobrando da mãe cuidados específicos de nutrição, cuidados com a gastrostomia, medicação, prevenção de acidentes domésticos, e orientando-a como guardar material de limpeza.The purpose of the present work is to report a case study on a malnourished 6 year old suffering from esophagus stenosis. As a methodological strategy data collection was performed through studies of medical charts and house visits. It was observed a lack of perception by the family regarding the dangers of having cleaning products within the reach of the child. The necessity of attendance of the health team (nurse, psychologist, doctor, social worker and nutritionist, guiding the mother with respect to special care with nutrition, care with the gastrotomy, medication, and domestic accident prevention, with advice on how to keep cleaning material.

  20. A case of recurrent autoimmune hemolytic anemia during remission associated with acute pure red cell aplasia and hemophagocytic syndrome due to human parvovirus B19 infection successfully treated by steroid pulse therapy with a review of the literature.

    Science.gov (United States)

    Sekiguchi, Yasunobu; Shimada, Asami; Imai, Hidenori; Wakabayashi, Mutsumi; Sugimoto, Keiji; Nakamura, Noriko; Sawada, Tomohiro; Komatsu, Norio; Noguchi, Masaaki

    2014-01-01

    The patient was a 47-year-old man diagnosed as having autoimmune hemolytic anemia (AIHA) in April 2011. He also had a congenital chromosomal abnormality, a balanced translocation. Treatment with prednisolone (PSL) 60 mg/day resulted in resolution of the AIHA, and the treatment was completed in November 2011. While the patient no longer had anemia, the direct and indirect Coombs tests remained positive. In May 2013, he developed recurrent AIHA associated with acute pure red cell aplasia (PRCA) and hemophagocytic syndrome (HPS) caused by human parvovirus B19 (HPV B19) infection. Tests for anti-erythropoietin and anti-erythropoietin receptor antibodies were positive. Steroid pulse therapy resulted in resolution of the AIHA, PRCA, as well as HPS. The serum test for anti-erythropoietin antibodies also became negative after the treatment. However, although the serum was positive for anti-HPV B19 IgG antibodies, the patient continued to have a low CD4 lymphocyte count (CD4, <300/μL) and persistent HPV B19 infection (HPV B19 DNA remained positive), suggesting the risk of recurrence and bone marrow failure.

  1. Aspergillosis in immunocompromised children acute myeloid leukemia and bone marrow aplasia.: Report of two cases Aspergilose em crianças imunocomprometidas com leucemia mielóide aguda e aplasta de medula óssea: Registro de 2 casos

    Directory of Open Access Journals (Sweden)

    Maria Zilda de Aquino

    1994-10-01

    Full Text Available Two cases of Aspergillosis in immunocompromised children are reported. Both were caused by Aspergillns flavus. Early diagnosis and treatment led to the remission of the process. One patient had acute myeloid leukemia; the fungus was isolated from the blood. The other patient with bone marrow aplasia, presented an invasive aspergillosis of the paranasal sinuses with dissemination of fungal infection; the diagnosis was obtained by histology and culture of biopsied tissue from a palatal ulceration.No presente trabalho são registrados dois casos de aspergilose em crianças imunocomprometidas. O estudo micológico completo identificou Aspergillus flavus como agente dos dois processos. A presença cada vez mais frequente da aspergilose invasiva deve-se ao número crescente de pacientes imunocomprometidos, muitos com hemopatias graves submetidos à quimioterapia. O diagnóstico precoce em um dos casos possibilitou remissão do processo. Tratava-se de paciente com leucemia mielóide aguda, tendo sido isolado o fungo do sangue circulante. O segundo caso evoluiu para óbito, com infecção fúngica generalizada.

  2. El recuerdo viaja por Italia

    Directory of Open Access Journals (Sweden)

    Néstor Madrid Malo

    1965-09-01

    Full Text Available Espero que mis lectores puedan acompañarme en este viaje del recuerdo por Italia, en esta travesía restrospectiva por el cuerpo duradero, por el dorso sustantivo - vertebrado dulcemente, ásperamente, por el vasto cinturón apenínico- de un país donde la vida tiene una manera tan suya de ser grata, de transcurrir en todo momento significativamente. Y donde cada instante, cada sitio, está signado de plenitudes inefables, de expresivos modos de mostrársenos e insinuársenos, hasta hacerse todos ellos, por siempre, memorables e insistentes habitantes de nuestros mejores sueños y vigilias.

  3. Comparison of the oral health-related quality of life and dental pain in symptomatic irreversible pulpitis and pericoronitis

    Directory of Open Access Journals (Sweden)

    Hale Cimilli

    2012-09-01

    Conclusion: The DePaQ gives detailed information about clinical conditions related to pain and the OHRQoL status in both symptomatic irreversible pulpitis and pericoronitis. VAS scores differed between the groups according to the DePaQ items.

  4. Effect of preoperative alprazolam on the success of inferior alveolar nerve block for teeth with irreversible pulpitis.

    Science.gov (United States)

    Khademi, Abbas Ali; Saatchi, Masoud; Minaiyan, Mohsen; Rostamizadeh, Nasim; Sharafi, Fatemeh

    2012-10-01

    Success of inferior alveolar nerve (IAN) block decreases in patients with irreversible pulpitis. The purpose of this study was to evaluate the effect of preoperative administration of alprazolam on the success of the IAN block for teeth with irreversible pulpitis. Sixty patients with irreversible pulpitis of a mandibular molar were selected for this prospective, randomized, double-blind, placebo-controlled study. The patients received identical capsules of either 0.5 mg of alprazolam or placebo 45 minutes before the administration of a conventional IAN block. Access cavity preparation was initiated 15 minutes after the IAN block injection. Lip numbness was recorded for all the patients. Success was defined as no or mild pain on the basis of visual analogue scale recordings during access cavity preparation and initial instrumentation. Data were analyzed by t test, Mann-Whitney, and χ(2) tests. The success rate was 53% for alprazolam group and 40% for placebo group, with no significant difference between the 2 groups (P = .301). Within the scope of the current study, preoperative oral administration of 0.5 mg of alprazolam did not improve the success of the IAN block in mandibular molars in patients with irreversible pulpitis, and the success rate was not adequate to ensure profound pulpal anesthesia. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. Disinfection procedures: their efficacy and effect on dimensional accuracy and surface quality of an irreversible hydrocolloid impression material.

    LENUS (Irish Health Repository)

    Rentzia, A

    2011-02-01

    This study investigated the antibacterial efficacy and effect of 0.55% ortho-phthalaldehyde (Cidex OPA(®)) and 0.5% sodium hypochlorite (NaOCl) on the dimensional accuracy and surface quality of gypsum casts retrieved from an irreversible hydrocolloid impression material.

  6. An Evaluation of Irreversible Psychosurgical Treatment of Patients With Obsessive-Compulsive Disorder in the Netherlands, 2001-2008

    NARCIS (Netherlands)

    van Vliet, I. M.; van Well, E. P. L.; Bruggeman, Richard; Campo, Joost A.; Hijman, R.; van Megen, H. J. G. M.; van Balkom, A. J. L. M.; van Rijen, P. C.

    Admissions for irreversible psychosurgical treatment of obsessive-compulsive disorder (OCD) by the Working Group for Indication Psychosurgery in the Netherlands were analyzed, and the postsurgical effects on symptom severity and quality of life were evaluated. The data were extracted from patient

  7. Unveiling the irreversible performance degradation of organo-inorganic halide perovskite films and solar cells during heating and cooling processes.

    Science.gov (United States)

    Mamun, Abdullah Al; Ava, Tanzila Tasnim; Byun, Hye Ryung; Jeong, Hyeon Jun; Jeong, Mun Seok; Nguyen, Loi; Gausin, Christine; Namkoong, Gon

    2017-07-26

    While organo-inorganic halide perovskite solar cells show great potential to meet future energy needs, their thermal instability raises serious questions about their commercialization viability. At present, the stability of perovskite solar cells has been studied under various environmental conditions including humidity and temperature. Nonetheless, understanding of the performance of CH 3 NH 3 PbI 3-x Cl x perovskite solar cells is limited. This study reports the irreversible performance degradation of CH 3 NH 3 PbI 3-x Cl x perovskite solar cells during the heating and cooling processes under AM 1.5 and unveils what triggers the irreversible performance degradation of solar cells. Particularly, the primary cause of the irreversible performance degradation of CH 3 NH 3 PbI 3-x Cl x is quantitatively analyzed by monitoring in real time the development of deteriorated crystallinity, charge trapping/detrapping, trap depth, and the PbI 2 phase, namely a critical signal of perovskite degradation while varying the temperature of the perovskite films and solar cells. Most surprisingly, it is revealed that the degradation of both perovskite films and solar cells was triggered at ∼70 °C. Remarkably, even after the device temperature cooled down to room temperature, the degraded performance of the solar cells persisted with increasing charge trapping and further development of the PbI 2 phase. Identification of the irreversible performance degradation of perovskite solar cells provides guidance for future development of more stable perovskite solar cells.

  8. Preliminary Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging to Detect Residual Prostate Cancer Following Focal Therapy with Irreversible Electroporation

    NARCIS (Netherlands)

    Scheltema, Matthijs J.; Chang, John I.; van den Bos, Willemien; Böhm, Maret; Delprado, Warick; Gielchinsky, Ilan; de Reijke, Theo M.; de la Rosette, Jean J.; Siriwardana, Amila R.; Shnier, Ron; Stricker, Phillip D.

    2017-01-01

    It is recommended to perform multiparametric magnetic resonance imaging (mpMRI) in the follow-up following focal therapy of prostate cancer (PCa). To determine the diagnostic accuracy of mpMRI to detect residual PCa following focal therapy with irreversible electroporation. Seventy-six patients with

  9. Thermodynamic optimisation and computational analysis of irreversibilities in a small-scale wood-fired circulating fluidised bed adiabatic combustor

    CSIR Research Space (South Africa)

    Baloyi, J

    2014-06-01

    Full Text Available An analysis of irreversibilities generated due to combustion in an adiabatic combustor burning wood was conducted. This was done for a reactant mixture varying from a rich to a lean mixture. A non-adiabatic non-premixed combustion model of a...

  10. Entransy analysis of irreversible heat pump using Newton and Dulong–Petit heat transfer laws and relations with its performance

    International Nuclear Information System (INIS)

    Açıkkalp, Emin

    2014-01-01

    Highlights: • Entransy analysis was made for irreversible heat pump. • Newton and Dulong–Petit heat transfer laws were used. • Entransy dissipations were defined and determined. • Relations between entransy and other thermodynamic parameters were determined. - Abstract: An irreversible heat pump was investigated via entransy analysis and performance criteria. In the analyses, two different convective heat transfer laws were applied to the considered system: the Newton and Dulong–Petit heat transfer laws. The irreversibilities in the system are the result of a finite heat transfer rate, a heat leak and internal irreversibilities, including friction, turbulence etc. In this study, a thermodynamic analysis was performed in detail, and the numerical solutions were used for the conducted analysis. The maximum entransy dissipation (critical points) ranges from 18436.7 kW K to 18855.3 kW K according to y for Newton’s law; however, there is no maximum point for the Dulon–Petit law. It can be concluded from this study that entransy should be used among the basic thermodynamic criteria

  11. Insufficient evidence to assess the effectiveness of antibiotics for irreversible pulpitis.

    Science.gov (United States)

    George, Roy

    2014-03-01

    The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase and the US National Institutes of Health Trials Register. Randomised controlled trials (RCTs) which compared pain relief with systemic antibiotics and analgesics, against placebo and analgesics in the acute preoperative phase of irreversible pulpitis. Study selection, risk of bias assessment and data extraction were carried out independently by two reviewers. Pooling of data was not possible and a descriptive summary is presented. One trial assessed at low risk of bias, involving 40 participants, was included in this update of the review. The quality of the body of evidence was rated low for the different outcomes. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the seven-day study period.There was insufficient evidence to claim or refute a benefit for penicillin for pain intensity. There was no significant difference in the mean total number of ibuprofen tablets taken over the study period: 9.2 (standard deviation (SD) 6.02) in the penicillin group versus 9.6 (SD 6.34) in the placebo group; mean difference -0.40 (95% confidence interval (CI) -4.23 to 3.43; P value = 0.84). This applied equally for the mean total number of Tylenol tablets: 6.9 (SD 6.87) used in the penicillin group versus 4.45 (SD 4.82) in the placebo group; mean difference 2.45 (95% CI -1.23 to 6.13; P value = 0.19). Our secondary outcome on reporting of adverse events was not addressed in this study. This systematic, review which was based on one low-powered small sample trial assessed as a low risk of bias, illustrates that there is insufficient evidence to determine whether antibiotics reduce pain or not compared to not having antibiotics. The results of this review confirm the necessity for further larger sample and methodologically sound trials that can provide additional evidence as to whether antibiotics

  12. Loschmidt echo in many-spin systems: a quest for intrinsic decoherence and emergent irreversibility

    Science.gov (United States)

    Zangara, Pablo R.; Pastawski, Horacio M.

    2017-03-01

    If a magnetic polarization excess is locally injected in a crystal of interacting spins in thermal equilibrium, this ‘excitation’ would spread as consequence of spin-spin interactions. Such an apparently irreversible process is known as spin diffusion and it can lead the system back to ‘equilibrium’. Even so, a unitary quantum dynamics would ensure a precise memory of the non-equilibrium initial condition. Then, if at a certain time, say t/2, an experimental protocol reverses the many-body dynamics by changing the sign of the effective Hamiltonian, it would drive the system back to the initial non-equilibrium state at time t. As a matter of fact, the reversal is always perturbed by small experimental imperfections and/or uncontrolled internal or environmental degrees of freedom. This limits the amount of signal M(t) recovered locally at time t. The degradation of M(t) accounts for these perturbations, which can also be seen as the sources of decoherence. This general idea defines the Loschmidt echo (LE), which embodies the various time-reversal procedures implemented in nuclear magnetic resonance. Here, we present an invitation to the study of the LE following the pathway induced by the experiments. With such a purpose, we provide a historical and conceptual overview that briefly revisits selected phenomena that underlie the LE dynamics including chaos, decoherence, localization and equilibration. This guiding thread ultimately leads us to the discussion of decoherence and irreversibility as an emergent phenomenon. In addition, we introduce the LE formalism by means of spin-spin correlation functions in a manner suitable for presentation in a broad scope physics journal. Last, but not least, we present new results that could trigger new experiments and theoretical ideas. In particular, we propose to transform an initially localized excitation into a more complex initial state, enabling a dynamically prepared LE. This induces a global definition of the LE in

  13. Energy Efficient Operation of Distillation Columns and a Reactor Applying Irreversible Thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Koeijer, Gelein M. de

    2002-05-01

    In this thesis the entropy production rates of diabatic distillation columns and a SO{sub 2} converter were minimised. This is the same as maximising the second law energy efficiency of the systems. The development of chemical industry can be made more sustainable by knowing this minimum. We found that the entropy production rate of distillation could be reduced up to 50 %. In order to achieve this reduction, heat exchangers were added on each tray. The characteristics of an optimum distillation column were presented. Furthermore, the entropy production rate of a SO{sub 2} converter was reduced with 16.7 % by altering the heights of catalytic beds, transfer areas of heat exchangers, and temperature differences over heat exchangers. These reductions show that there is still a large improvement potential in chemical industry. By applying the improved operations the world oil production can be reduced in the order of magnitude of 1 %. A similar reduction in the emission of the greenhouse gas CO{sub 2} can be expected. For deriving the entropy production rate in a systematic manner the theory of irreversible thermodynamics was useful. A simpler and a more complicated equation for the entropy production rate of distillation were derived. The simpler equation used only one force-flux product. It was suitable for minimisation of the entropy production rate of columns with the assumption of equilibrium between the outlets on each tray. The more complicated equation was able to describe satisfactorily the entropy production rate of an experimental column that separated the non-ideal mixture water-ethanol. It was next used to derive an extended set of transport equations for distillation, that includes the interface and the Soret effect (or thermal diffusion). Finally, irreversible thermodynamics was used to describe the contribution to the entropy production rate of heat transfer in heat exchangers. This contribution had a significant impact on the results of the

  14. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    Energy Technology Data Exchange (ETDEWEB)

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with (/sup 3/H)yohimbine, whereas (/sup 3/H)clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, (/sup 3/H) clonidine and (/sup 3/H)yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of (/sup 3/H)clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations.

  15. Incidence of missed inferior alveolar nerve blocks in vital asymptomatic subjects and in patients with symptomatic irreversible pulpitis.

    Science.gov (United States)

    Fowler, Sara; Reader, Al; Beck, Mike

    2015-05-01

    The purpose of this retrospective study was to determine the incidence of missed inferior alveolar nerve (IAN) blocks by using a 1- or 2-cartridge volume of 2% lidocaine with 1:100,000 epinephrine in vital asymptomatic teeth and in emergency patients with symptomatic irreversible pulpitis. As part of 37 studies, 3169 subjects/patients were evaluated for missed IAN blocks. The study included 2450 asymptomatic subjects and 719 emergency patients presenting with symptomatic irreversible pulpitis. Each subject or patient received either a 1- or 2-cartridge volume of 2% lidocaine with 1:100,000 epinephrine. A missed block was defined as no lip numbness at 15-20 minutes after the IAN block. The effect of anesthetic volume on the incidence of missed blocks was assessed by using mixed models logistic regression with individual studies as a random effect. The incidence of missed blocks for asymptomatic subjects was 6.3% for the 1-cartridge volume and 3.8% for the 2-cartridge volume. For patients presenting with irreversible pulpitis, the incidence of missed blocks was 7.7% for the 1-cartridge volume and 2.3% for the 2-cartridge volume. In both asymptomatic subjects and patients with irreversible pulpitis, the 2-cartridge volume was significantly (P = .0395) better than the 1-cartridge volume. There were no significant effects for pulpal diagnosis (P = .7523) or the pulpal diagnosis and anesthetic volume interaction (P = .3973). Concerning missed IAN blocks, we concluded that administration of a 2-cartridge volume was significantly better (P = .0395) than a 1-cartridge volume in both asymptomatic subjects and emergency patients presenting with irreversible pulpitis. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Responsabilidade civil por abandono afetivo

    OpenAIRE

    Fidélis, Maria de Lourdes

    2013-01-01

    Este estudo tem por objetivo a análise da responsabilidade civil por abandono afetivo na relação paterno-filial a partir de recentes decisões dos tribunais brasileiros. Inicialmente discorre sobre a evolução da família contemporânea. Examina os elementos da responsabilidade civil objetivando uma interseção entre o novo Direito de Família e as transformações no dever de indenizar. A partir de dois casos paradigmáticos escolhidos busca-se encontrar os fundamentos e finalidades das demandas por ...

  17. Irreversible bonding of polyimide and polydimethylsiloxane (PDMS) based on a thiol-epoxy click reaction

    International Nuclear Information System (INIS)

    Hoang, Michelle V; Chung, Hyun-Joong; Elias, Anastasia L

    2016-01-01

    Polyimide is one of the most popular substrate materials for the microfabrication of flexible electronics, while polydimethylsiloxane (PDMS) is the most widely used stretchable substrate/encapsulant material. These two polymers are essential in fabricating devices for microfluidics, bioelectronics, and the internet of things; bonding these materials together is a crucial challenge. In this work, we employ click chemistry at room temperature to irreversibly bond polyimide and PDMS through thiol-epoxy bonds using two different methods. In the first method, we functionalize the surfaces of the PDMS and polyimide substrates with mercaptosilanes and epoxysilanes, respectively, for the formation of a thiol-epoxy bond in the click reaction. In the second method, we functionalize one or both surfaces with mercaptosilane and introduce an epoxy adhesive layer between the two surfaces. When the surfaces are bonded using the epoxy adhesive without any surface functionalization, an extremely small peel strength (<0.01 N mm −1 ) is measured with a peel test, and adhesive failure occurs at the PDMS surface. With surface functionalization, however, remarkably higher peel strengths of ∼0.2 N mm −1 (method 1) and  >0.3 N mm −1 (method 2) are observed, and failure occurs by tearing of the PDMS layer. We envision that the novel processing route employing click chemistry can be utilized in various cases of stretchable and flexible device fabrication. (paper)

  18. Irreversible Thermodynamic Description of Dark Matter and Radiation Creation during Inflationary Reheating

    Directory of Open Access Journals (Sweden)

    Juntong Su

    2017-01-01

    Full Text Available We investigate matter creation processes during the reheating period of the early Universe, by using the thermodynamic of open systems. The Universe is assumed to consist of the inflationary scalar field, which, through its decay, generates relativistic matter and pressureless dark matter. The inflationary scalar field transfers its energy to the newly created matter particles, with the field energy decreasing to near zero. The equations governing the irreversible matter creation are obtained by combining the thermodynamics description of the matter creation and the gravitational field equations. The role of the different inflationary scalar field potentials is analyzed by using analytical and numerical methods. The values of the energy densities of relativistic matter and dark matter reach their maximum when the Universe is reheated up to the reheating temperature, which is obtained as a function of the scalar field decay width, the scalar field particle mass, and the cosmological parameters. Particle production leads to the acceleration of the Universe during the reheating phase, with the deceleration parameter showing complex dynamics. Once the energy density of the scalar field becomes negligible with respect to the matter densities, the expansion of the Universe decelerates, and inflation has a graceful exit.

  19. Avoiding neuromuscular stimulation in liver irreversible electroporation using radiofrequency electric fields

    Science.gov (United States)

    Castellví, Quim; Mercadal, Borja; Moll, Xavier; Fondevila, Dolors; Andaluz, Anna; Ivorra, Antoni

    2018-02-01

    Electroporation-based treatments typically consist of the application of high-voltage dc pulses. As an undesired side effect, these dc pulses cause electrical stimulation of excitable tissues such as motor nerves. The present in vivo study explores the use of bursts of sinusoidal voltage in a frequency range from 50 kHz to 2 MHz, to induce irreversible electroporation (IRE) whilst avoiding neuromuscular stimulation. A series of 100 dc pulses or sinusoidal bursts, both with an individual duration of 100 µs, were delivered to rabbit liver through thin needles in a monopolar electrode configuration, and thoracic movements were recorded with an accelerometer. Tissue samples were harvested three hours after treatment and later post-processed to determine the dimensions of the IRE lesions. Thermal damage due to Joule heating was ruled out via computer simulations. Sinusoidal bursts with a frequency equal to or above 100 kHz did not cause thoracic movements and induced lesions equivalent to those obtained with conventional dc pulses when the applied voltage amplitude was sufficiently high. IRE efficacy dropped with increasing frequency. For 100 kHz bursts, it was estimated that the electric field threshold for IRE is about 1.4 kV cm-1 whereas that of dc pulses is about 0.5 kV cm-1.

  20. Irreversible Wash Aid Additive for Cesium Mitigation. Small-Scale Demonstration and Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-01

    The Irreversible Wash Aid Additive process has been under development by the U.S. Environmental Protection Agency (EPA) and Argonne National Laboratory (Argonne). This process for radioactive cesium mitigation consists of a solution to wash down contaminated structures, roadways, and vehicles and a sequestering agent to bind the radionuclides from the wash water and render them environmentally immobile. The purpose of this process is to restore functionality to basic services and immediately reduce the consequences of a radiologically-contaminated urban environment. Research and development have resulted in a down-selection of technologies for integration and demonstration at the pilot-scale level as part of the Wide Area Recovery and Resiliency Program (WARRP) under the Department of Homeland Security and the Denver Urban Area Security Initiative. As part of developing the methods for performing a pilot-scale demonstration at the WARRP conference in Denver in 2012, Argonne conducted small-scale field experiments at Separmatic Systems. The main purpose of these experiments was to refine the wash water collection and separations systems and demonstrate key unit operations to help in planning for the large scale demonstration in Denver. Since the purpose of these tests was to demonstrate the operations of the system, we used no radioactive materials. After a brief set of experiments with the LAKOS unit to familiarize ourselves with its operation, two experiments were completed on two separate dates with the Separmatic systems.

  1. Irreversible membrane fouling abatement through pre-deposited layer of hierarchical porous carbons

    KAUST Repository

    Hamad, Juma

    2014-11-01

    In this work, dual-templated hierarchical porous carbons (HPCs), produced from a coupled ice-hard templating approach, are shown to be a highly effective solution to the commonly occurring problem of irreversible fouling of low-pressure membranes used for pre-treatment in wastewater reuse. For the first time, dual-templated HPCs, along with their respective counterparts - single-templated meso-porous carbon (MPCs) (without macropores) - are tested in terms of their fouling reduction capacity and ability to remove different effluent organic matter fractions present in wastewater and compared with a commercially available powdered activated carbon (PAC). The synthesized HPCs provided exceptional fouling abatement, a 4-fold higher fouling reduction as compared to the previously reported best performing commercial PAC and ~2.5-fold better fouling reduction than their respective mesoporous counterpart. Thus, it is shown that not only mesoporosity, but macroporosity is also necessary to achieve high fouling reduction, thus emphasizing the need for dual templating. In the case of HPCs, the pre-deposition technique is also found to outperform the traditional sorbent-feed mixing approach, mainly in terms of removal of fouling components. Based on their superior performance, a high permeability (ultra-low-pressure) membrane consisting of the synthesized HPC pre-deposited on a large pore size membrane support (0.45μm membrane), is shown to give excellent pre-treatment performance for wastewater reuse application. © 2014 Elsevier Ltd.

  2. Irreversible electroporation ablation area enhanced by synergistic high- and low-voltage pulses.

    Directory of Open Access Journals (Sweden)

    Chenguo Yao

    Full Text Available Irreversible electroporation (IRE produced by a pulsed electric field can ablate tissue. In this study, we achieved an enhancement in ablation area by using a combination of short high-voltage pulses (HVPs to create a large electroporated area and long low-voltage pulses (LVPs to ablate the electroporated area. The experiments were conducted in potato tuber slices. Slices were ablated with an array of four pairs of parallel steel electrodes using one of the following four electric pulse protocols: HVP, LVP, synergistic HVP+LVP (SHLVP or LVP+HVP. Our results showed that the SHLVPs more effectively necrotized tissue than either the HVPs or LVPs, even when the SHLVP dose was the same as or lower than the HVP or LVP doses. The HVP and LVP order mattered and only HVPs+LVPs (SHLVPs treatments increased the size of the ablation zone because the HVPs created a large electroporated area that was more susceptible to the subsequent LVPs. Real-time temperature change monitoring confirmed that the tissue was non-thermally ablated by the electric pulses. Theoretical calculations of the synergistic effects of the SHLVPs on tissue ablation were performed. Our proposed SHLVP protocol provides options for tissue ablation and may be applied to optimize the current clinical IRE protocols.

  3. Performance analysis for an irreversible variable temperature heat reservoir closed intercooled regenerated Brayton cycle

    International Nuclear Information System (INIS)

    Wang Wenhua; Chen Lingen; Sun Fengrui; Wu Chih

    2003-01-01

    In this paper, the theory of finite time thermodynamics is used in the performance analysis of an irreversible closed intercooled regenerated Brayton cycle coupled to variable temperature heat reservoirs. The analytical formulae for dimensionless power and efficiency, as functions of the total pressure ratio, the intercooling pressure ratio, the component (regenerator, intercooler, hot and cold side heat exchangers) effectivenesses, the compressor and turbine efficiencies and the thermal capacity rates of the working fluid and the heat reservoirs, the pressure recovery coefficients, the heat reservoir inlet temperature ratio, and the cooling fluid in the intercooler and the cold side heat reservoir inlet temperature ratio, are derived. The intercooling pressure ratio is optimized for optimal power and optimal efficiency, respectively. The effects of component (regenerator, intercooler and hot and cold side heat exchangers) effectivenesses, the compressor and turbine efficiencies, the pressure recovery coefficients, the heat reservoir inlet temperature ratio and the cooling fluid in the intercooler and the cold side heat reservoir inlet temperature ratio on optimal power and its corresponding intercooling pressure ratio, as well as optimal efficiency and its corresponding intercooling pressure ratio are analyzed by detailed numerical examples. When the heat transfers between the working fluid and the heat reservoirs are executed ideally, the pressure drop losses are small enough to be neglected and the thermal capacity rates of the heat reservoirs are infinite, the results of this paper replicate those obtained in recent literature

  4. Pressure-induced irreversible metallization accompanying the phase transitions in S b2S3

    Science.gov (United States)

    Dai, Lidong; Liu, Kaixiang; Li, Heping; Wu, Lei; Hu, Haiying; Zhuang, Yukai; Yang, Linfei; Pu, Chang; Liu, Pengfei

    2018-01-01

    We have revealed S b2S3 to have two phase transitions and to undergo metallization using a diamond anvil cell at around 5.0, 15.0, and 34.0 GPa, respectively. These results were obtained on the basis of high-pressure Raman spectroscopy, temperature-dependent conductivity measurements, atomic force microscopy, high-resolution transmission electron microscopy, and first-principles calculations. The first phase transition at ˜5.0 GPa is an isostructural phase transition, which is manifested in noticeable changes in five Raman-active modes and the slope of the conductivity because of a change in the electronic structure. The second pressure-induced phase transition was characterized by a discontinuous change in the slope of conductivity and a new low-intensity Raman mode at ˜15.0 GPa . Furthermore, a semiconductor-to-metal transition was found at ˜34.0 GPa , which was accompanied by irreversible metallization, and it could be attributed to the permanently plastic deformation of the interlayer spacing. This high-pressure behavior of S b2S3 will help us to understand the universal crystal structure evolution and electrical characteristics for A2B3 -type compounds, and to facilitate their application in electronic devices.

  5. Irreversible electropermeabilization of the human pathogen Candida albicans: an in-vitro experimental study.

    Science.gov (United States)

    Novickij, Vitalij; Grainys, Audrius; Svediene, Jurgita; Markovskaja, Svetlana; Paskevicius, Algimantas; Novickij, Jurij

    2015-02-01

    Pathogenic fungi cause many life-threatening infections, especially among individuals with immune system dysfunction. The antifungal drugs commonly used to suppress fungal pathogens can result in long-lasting and toxic therapy. In this work, irreversible electropermeabilization was used to investigate the dynamics of the decrease in Candida albicans colony vitality after application of a pulsed electric field (PEF) and use of antifungal drugs. The fungi were subjected to single 250-µs to 2-ms (0.5-2.5 kV/cm) pulses or repeated short 5-µs pulses, and efficacy was compared. It was shown that electropermeabilization combined with antifungal agents results in rapid and more effective treatment, eliminating more than 90% of C. albicans colony-forming units in a single procedure, which is advantageous in biomedicine. It was also observed that, because of application of PEF and use of the antifungal agents, the Candida cells form cell aggregates and average live cell size is reduced by as much as 53%.

  6. The Effects of Irreversible Electroporation on the Colon in a Porcine Model.

    Science.gov (United States)

    Luo, Xiaomei; Liang, Xianjun; Li, Jiannan; Shi, Jian; Zhang, Wenlong; Chai, Wei; Wu, Jiuping; Guo, Shuai; Fang, Gang; Zhou, Xulong; Zhang, Jianhua; Xu, Kecheng; Zeng, Jianying; Niu, Lizhi

    2016-01-01

    Irreversible electroporation (IRE) is a method of targeted cell ablation which has been suggested as a potential cancer therapy as it leaves structures such as blood vessels and the extracellular matrix intact, thereby allowing the rapid recovery of healthy tissue. Here, we investigated the effects of IRE on the colon in vivo in a porcine model. IRE ablation was performed on the colon walls of 12 female Tibet mini-pigs, creating a total of 24 lesions. Lesions were monitored periodically by endoscopy. The pigs were euthanized 7, 14, 21 or 28 days after IRE ablation and the colons harvested for gross and histological analysis. Sections were stained with hematoxylin and eosin (H&E), Masson's trichrome (MT) stain and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. All pigs tolerated the ablation procedure without serious clinical symptoms or complications. There was no evidence of perforation by endoscopy or gross postmortem examination. All lesions were characterized by necrotic cell death with mild inflammation and hyperemia, with a sharp demarcation between ablated and adjacent normal tissue. A fibrous scar was observed in the ablated colon tissue. Histological analysis revealed damage to each layer of the colon. Histopathology findings also showed the preservation of extracellular structures and the recovery of the ablated colon. The complete ablation of the target area, its rapid recovery and the lack of posttreatment symptoms suggest that IRE ablation may be a promising therapy for tumors located adjacent to or violating the colon wall.

  7. Irreversibility of a bad start: early exposure to osmotic stress limits growth and adaptive developmental plasticity.

    Science.gov (United States)

    Wu, Chi-Shiun; Gomez-Mestre, Ivan; Kam, Yeong-Choy

    2012-05-01

    Harsh environments experienced early in development have immediate effects and potentially long-lasting consequences throughout ontogeny. We examined how salinity fluctuations affected survival, growth and development of Fejervarya limnocharis tadpoles. Specifically, we tested whether initial salinity effects on growth and rates of development were reversible and whether they affected the tadpoles' ability to adaptively accelerate development in response to deteriorating conditions later in development. Tadpoles were initially assigned to either low or high salinity, and then some were switched between salinity levels upon reaching either Gosner stage 30 (early switch) or 38 (late switch). All tadpoles initially experiencing low salinity survived whereas those initially experiencing high salinity had poor survival, even if switched to low salinity. Growth and developmental rates of tadpoles initially assigned to high salinity did not increase after osmotic stress release. Initial low salinity conditions allowed tadpoles to attain a fast pace of development even if exposed to high salinity afterwards. Tadpoles experiencing high salinity only late in development metamorphosed faster and at a smaller size, indicating an adaptive acceleration of development to avoid osmotic stress. Nonetheless, early exposure to high salinity precluded adaptive acceleration of development, always causing delayed metamorphosis relative to those in initially low salinity. Our results thus show that stressful environments experienced early in development can critically impact life history traits, having long-lasting or irreversible effects, and restricting their ability to produce adaptive plastic responses.

  8. The anthropological actions on Tandil natural landscape produced by irreversible alterations and changes in the landscape

    International Nuclear Information System (INIS)

    Bernabe, M.; Morrone, M.

    2007-01-01

    The anthropological actions on Tandil natural landscape are producing irreversible alterations and changes in the landscape. The changes take place mainly in: a) Depredation mining activity on the hills, b) Advance of the constructions on the hills. c) Superficial drainage changes by tubes and dike deficiencies) Stuffed of diggings with industrials solids remainders. The presence of System of Tandilia hills grants a high landscaping and economic value to the area. The mining activity and the related tourism constructions are in constant development. The mentioned activities are harnessed by the economic height of last five years, since Tandil is chosen as place of permanent residence by job and educational supply, and tourism by near accessibility from Buenos Aires city. Like consequence, it takes place great urban expansion where particular houses stand out, also districts, countries; and the related ones to the tourist activity like inns, that are located on the hills, generating changes in the landscape. The study area is located in the S-SW-SE sector of the city of Tandil, head of the party homonym of the Southeastern center of the province of Buenos Aires. The purpose of this paper aim to emphasize the anthropological action like main agent the natural landscape alteration, generating environmental problems. Aerial photography, and topographic maps to scale: 1:50000 were used. (author)

  9. Irreversible thermodynamics models and constitutive equations of the irradiation induced deformation and damage accumulating processes

    International Nuclear Information System (INIS)

    Wassilew, C.

    1989-11-01

    This report gives an overall evaluation of several in-reactor deformation and creep-rupture experiments performed in BR-2, FFTF, and Rapsodie on pressurised tubes of the stabilized austenitic stainless steels 1.4970, 1.4981, 1.4988, and the nickel base alloy Hastelloy-X. The irradiation induced deformation processes observed in the components operating in a neutron environment can be divided into two main groups: 1. volume conserving creep and 2. volumetric swelling. Since the observed deformation as well as damage accumulating phenomena are caused by the same constrained generated and free disposable point defects and helium atoms, it is obvious and advisable to analyze, and to model simultaneously the ensemble of the elementary mechanisms and processes effective at the same time. Phenomenological models based on the thermodynamics of irreversible processes have been developed, with the aim of: 1. grasping the partial relationships between the external variables and the response functions (creep, swelling, creep driven swelling, and time to rupture), 2. fathoming the rate-controlling mechanisms, 3. providing insight into the structural details and changes occurring during the deformation and the damage accumulating processes, 4. integrating the damage accumulating processes comprehensively, and 5. formulating the constitutive equations required to describe the elementary processes that generate plastic deformations as well as damage accumulation. (orig./MM)

  10. Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Chien-Hwa [Department of Civil and Environment Engineering, Nanya Institute of Technology, Taoyuan, Taiwan (China); Fang, Lung-Chen; Lateef, Shaik Khaja [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wu, Chung-Hsin, E-mail: chunghsinwu@yahoo.com.tw [Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan (China); Lin, Cheng-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China)

    2010-05-15

    Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including {alpha}-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

  11. Irreversible catalyst activation enables hyperpolarization and water solubility for NMR signal amplification by reversible exchange.

    Science.gov (United States)

    Truong, Milton L; Shi, Fan; He, Ping; Yuan, Bingxin; Plunkett, Kyle N; Coffey, Aaron M; Shchepin, Roman V; Barskiy, Danila A; Kovtunov, Kirill V; Koptyug, Igor V; Waddell, Kevin W; Goodson, Boyd M; Chekmenev, Eduard Y

    2014-12-04

    Activation of a catalyst [IrCl(COD)(IMes)] (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; COD = cyclooctadiene)] for signal amplification by reversible exchange (SABRE) was monitored by in situ hyperpolarized proton NMR at 9.4 T. During the catalyst-activation process, the COD moiety undergoes hydrogenation that leads to its complete removal from the Ir complex. A transient hydride intermediate of the catalyst is observed via its hyperpolarized signatures, which could not be detected using conventional nonhyperpolarized solution NMR. SABRE enhancement of the pyridine substrate can be fully rendered only after removal of the COD moiety; failure to properly activate the catalyst in the presence of sufficient substrate can lead to irreversible deactivation consistent with oligomerization of the catalyst molecules. Following catalyst activation, results from selective RF-saturation studies support the hypothesis that substrate polarization at high field arises from nuclear cross-relaxation with hyperpolarized (1)H spins of the hydride/orthohydrogen spin bath. Importantly, the chemical changes that accompanied the catalyst's full activation were also found to endow the catalyst with water solubility, here used to demonstrate SABRE hyperpolarization of nicotinamide in water without the need for any organic cosolvent--paving the way to various biomedical applications of SABRE hyperpolarization methods.

  12. Irreversibility line of an Ag-doped Hg-based superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, M F [Department of Physics, Faculty of Science, University of Cairo, Giza (Egypt); Hassen, A [Department of Physics, Faculty of Science, University of Fayoum, Fayoum (Egypt); Kunkel, H P, E-mail: Mohga40@yahoo.co [Department of Physics and Astronomy, University of Manitoba, Winnipeg R3T 2N2 (Canada)

    2010-08-15

    The effect of doping with Ag of the bulk superconducting Hg{sub 0.3}La{sub 0.7}Ba{sub 2}Ca{sub 3}(Cu{sub 1-x}Ag{sub x}){sub 4}O{sub 10+{delta}}, 0.1 {<=} x {<=} 0.3 phase (Hg-1234) is presented. The lattice parameter a = 3.824 A remains constant, while parameter c was found to increase from c = 19.0225 A (x = 0.0) to 19.08 A (x = 0.3) with the addition of Ag. The variation of T{sub c} versus the c-parameter exhibits a cupola-shaped behavior. The irreversibility line is thermally activated. The logarithmic plot of H{sub irr} versus (1 - T{sub irr}/T{sub c}(0)) shows a crossover temperature reflecting a transition from two- to three-dimensional behavior with increasing temperature. Fitting of the results to different models is discussed. Thermally activated de-pinning according to Matsushita's formula gives the best fit.

  13. TRPM8 axonal expression is decreased in painful human teeth with irreversible pulpitis and cold hyperalgesia

    Science.gov (United States)

    Alvarado, Lisa T.; Perry, Griffin M.; Hargreaves, Kenneth. M.; Henry, Michael A.

    2009-01-01

    Pulpitis pain may be triggered by a cold stimulus, yet the cellular mechanisms responsible for this phenomenon are largely unknown. One possible mechanism involves the direct activation of cold-responsive thermoreceptors. The purpose of this study was to evaluate the possible role of the TRPM8 thermoreceptor in cold-mediated noxious pulpal pain mechanisms by comparing expression patterns in pulpal nerves from healthy control molars to cold-sensitive painful molars with irreversible pulpitis. Samples were identically processed with the indirect immunofluorescence method and images obtained with confocal microscopy. The immunofluorescence intensity and area occupied by TRPM8 within N52/PGP9.5 identified nerve fibers were quantified. Results showed that relative to normal samples, TRPM8 nerve area expression was significantly less in the cold-sensitive painful samples (34.9% vs. 8%, p<0.03), but with no significant difference in immunofluorescence intensity between the two groups. These results suggest that TRPM8 is most likely not involved in cold-mediated noxious pulpal pain mechanisms. PMID:17889683

  14. Irreversibility in transformation behavior of equiatomic nickel-titanium alloy by electrical resistivity measurement

    International Nuclear Information System (INIS)

    Matsumoto, Hitoshi

    2004-01-01

    Measurements of the electrical resistivity were precisely performed on shape memory Ni 50 Ti 50 alloy in order to reveal the irreversible behavior of the thermoelastic martensitic transformation with thermal cycling. The hump in the electrical resistivity during cooling is enhanced with increasing the number of complete thermal cycles to result in a peak, although no peak in the electrical resistivity is observed on the reverse transformation during heating. The electrical resistivity in the low-temperature phase, of which the temperature dependence is linear, increases with increasing the number of complete thermal cycles. The temperature coefficient of the electrical resistivity in the temperature region of the high-temperature phase increases with elevating the temperature. The transformation is strongly influenced by incomplete thermal cycles to result in a peak in the resistivity even on the reverse transformation after incomplete thermal cycling. It is thought that the anomalous behavior such as enhancement of a resistivity-peak, the increase in the electrical resistivity of the low-temperature phase, and the nonlinear relation between the resistivity and the temperature in the high-temperature phase are attributable to the appearance of an intermediate phase stabilized by transformation-induced defects, the accumulation of the transformation-induced defects, and the electron scattering due to the softening of a phonon mode in the high-temperature phase, respectively. It proved useful to make more accurate measurements of the electrical resistivity in order to investigate the intrinsic behavior of the transformation in NiTi

  15. Histological and finite element analysis of cell death due to irreversible electroporation.

    Science.gov (United States)

    Long, G; Bakos, G; Shires, P K; Gritter, L; Crissman, J W; Harris, J L; Clymer, J W

    2014-12-01

    Irreversible electroporation (IRE) has been shown to be an effective method of killing cells locally. In contrast to radiofrequency ablation, the mechanism by which cells are thought to die via IRE is the creation of pores in cell membranes, without substantial increase in tissue temperature. To determine the degree to which cell death is non-thermal, we evaluated IRE in porcine hepatocytes in vivo. Using pulse widths of 10 µs, bursts of 3 kV square-wave pulses were applied through a custom probe to the liver of an anesthetized pig. Affected tissue was evaluated histologically via stainings of hematoxylin & eosin (H&E), nitroblue tetrazolium (NBT) to monitor cell respiration and TUNEL to gauge apoptosis. Temperature was measured during the application of electroporation, and heat transfer was modeled via finite element analysis. Cell death was calculated via Arrhenius kinetics. Four distinct zones were observed within the ring return electrode; heat-fixed tissue, coagulation, necrotic, and viable. The Arrhenius damage integral estimated complete cell death only in the first zone, where the temperature exceeded 70°C, and partial or no cell death in the other zones, where maximum temperature was approximately 45°C. Except for a limited area near the electrode tip, cell death in IRE is predominantly due to a non-thermal mechanism.

  16. Irreversible damage to auditory system functions caused by perinatal hypothyroidism in rats.

    Science.gov (United States)

    Wada, Hiromi; Yumoto, Shoko; Iso, Hiroyuki

    2013-01-01

    We examined the effect of perinatal hypothyroidism on auditory function in rats using a prepulse inhibition paradigm. Pregnant rats were treated with the antithyroid drug methimazole (1-methyl-2-mercaptoimidazole) from gestational day 15 to postnatal day 21 via drinking water at concentrations (w/v) of 0 (control), 0.002 (low dose), or 0.02% (high dose). Rats from methimazole-treated mothers were tested at ages 1, 6, and 12months using techniques to examine prepulse inhibition and startle response. The startle stimulus consisted of 40ms of white noise at 115dB, whereas the prepulse, which preceded the startle stimulus by 30ms, consisted of 20ms of white noise at 75, 85, or 95dB. When the prepulse intensity was 75 or 85dB, the high-dose group showed decreased prepulse inhibition percentages compared with the control and low-dose groups. The reduced percentages of prepulse inhibition did not return to control levels over the 12-month study period. In contrast, no differences in prepulse inhibition were observed among the three dose groups when prepulse intensity was 95dB. Moreover, the high-dose group displayed excessive reaction to auditory startle stimuli compared with the other groups. Reductions in plasma free thyroxine and body weight gain were observed in the high-dose group. We conclude that perinatal hypothyroidism results in irreversible damage to auditory function in rats. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. State-resolved attosecond reversible and irreversible dynamics in strong optical fields

    Science.gov (United States)

    Sabbar, Mazyar; Timmers, Henry; Chen, Yi-Jen; Pymer, Allison K.; Loh, Zhi-Heng; Sayres, Scott G.; Pabst, Stefan; Santra, Robin; Leone, Stephen R.

    2017-02-01

    Strong-field ionization (SFI) is a key process for accessing real-time quantum dynamics of electrons on the attosecond timescale. The theoretical foundation of SFI was pioneered in the 1960s, and later refined by various analytical models. While asymptotic ionization rates predicted by these models have been tested to be in reasonable agreement for a wide range of laser parameters, predictions for SFI on the sub-laser-cycle timescale are either beyond the scope of the models or show strong qualitative deviations from full quantum-mechanical simulations. Here, using the unprecedented state specificity of attosecond transient absorption spectroscopy, we follow the real-time SFI process of the two valence spin-orbit states of xenon. The results reveal that the irreversible tunnelling contribution is accompanied by a reversible electronic population that exhibits an observable spin-orbit-dependent phase delay. A detailed theoretical analysis attributes this observation to transient ground-state polarization, an unexpected facet of SFI that cannot be captured by existing analytical models that focus exclusively on the production of asymptotic electron/ion yields.

  18. In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

    International Nuclear Information System (INIS)

    Golberg, A; Laufer, S; Rabinowitch, H D; Rubinsky, B

    2011-01-01

    Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 deg. C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

  19. The Effects of Irreversible Electroporation on the Achilles Tendon: An Experimental Study in a Rabbit Model.

    Directory of Open Access Journals (Sweden)

    Yue Song

    Full Text Available To evaluate the potential effects of irreversible electroporation ablation on the Achilles tendon in a rabbit model and to compare the histopathological and biomechanical changes between specimens following electroporation ablation and radiofrequency ablation.A total of 140 six-month-old male New Zealand rabbits were used. The animals were randomly divided into two groups, 70 in the radiofrequency ablation group and 70 in the electroporation group. In situ ablations were applied directly to the Achilles tendons of rabbits using typical electroporation (1800 V/cm, 90 pulses and radiofrequency ablation (power control mode protocols. Histopathological and biomechanical evaluations were performed to examine the effects of electroporation ablation and radiofrequency ablation over time.Both electroporation and radiofrequency ablation produced complete cell ablation in the target region. Thermal damage resulted in tendon rupture 3 days post radiofrequency ablation. In contrast, electroporation-ablated Achilles tendons preserved their biomechanical properties and showed no detectable rupture at this time point. The electroporation-ablated tendons exhibited signs of recovery, including tenoblast regeneration and angiogenesis within 2 weeks, and the restoration of their integral structure was evident within 12 weeks.When applying electroporation to ablate solid tumors, major advantage could be that collateral damage to adjacent tendons or ligaments is minimized due to the unique ability of electroporation ablation to target the cell membrane. This advantage could have a significant impact on the field of tumor ablation near vital tendons or ligaments.

  20. The Effects of Irreversible Electroporation on the Achilles Tendon: An Experimental Study in a Rabbit Model.

    Science.gov (United States)

    Song, Yue; Zheng, Jingjing; Yan, Mingwei; Ding, Weidong; Xu, Kui; Fan, Qingyu; Li, Zhao

    2015-01-01

    To evaluate the potential effects of irreversible electroporation ablation on the Achilles tendon in a rabbit model and to compare the histopathological and biomechanical changes between specimens following electroporation ablation and radiofrequency ablation. A total of 140 six-month-old male New Zealand rabbits were used. The animals were randomly divided into two groups, 70 in the radiofrequency ablation group and 70 in the electroporation group. In situ ablations were applied directly to the Achilles tendons of rabbits using typical electroporation (1800 V/cm, 90 pulses) and radiofrequency ablation (power control mode) protocols. Histopathological and biomechanical evaluations were performed to examine the effects of electroporation ablation and radiofrequency ablation over time. Both electroporation and radiofrequency ablation produced complete cell ablation in the target region. Thermal damage resulted in tendon rupture 3 days post radiofrequency ablation. In contrast, electroporation-ablated Achilles tendons preserved their biomechanical properties and showed no detectable rupture at this time point. The electroporation-ablated tendons exhibited signs of recovery, including tenoblast regeneration and angiogenesis within 2 weeks, and the restoration of their integral structure was evident within 12 weeks. When applying electroporation to ablate solid tumors, major advantage could be that collateral damage to adjacent tendons or ligaments is minimized due to the unique ability of electroporation ablation to target the cell membrane. This advantage could have a significant impact on the field of tumor ablation near vital tendons or ligaments.

  1. Barthes’ Irreversible Codes: An Intertextual Reading of James Joyce’s “Araby”

    Directory of Open Access Journals (Sweden)

    Seyed Ali Booryazadeh

    2014-01-01

    Full Text Available Roland Barthes believes that semiology is the study of how language embodies the world. Semiotic codes, the paths of this embodiment, accordingly arouse his attention. Barthes in a structural analysis of Balzac’s “Sarrasine” in S/Z expounds five types and functions of these codes: proairetic (basic narrative actions; hermeneutic (narrative turning points; cultural (prior social knowledge; semic (medium-related codes and symbolic (themes. This research in a parallel manner explicates that “Araby,” one of the most widely read of James Joyce’s short stories, is abounded with two of these irreversible codes (proairetic and hermeneutic. The present study furthermore tries to show how with resort to a series of signs and the idea of intertextuality a literary text can provide probable answers for some ambiguous and questionable lexias that comprise the story’s hermeneutic code. It demonstrates that not only can the text of “Araby” be encoded by the same criteria Barthes encoded “Sarrasine” but also Joyce himself presents particular names for these codes.

  2. A Particle-Level Model of Irreversible Protein Adsorption with a Postadsorption Transition.

    Science.gov (United States)

    Van Tassel PR; Guemouri; Ramsden; Tarjus; Viot; Talbot

    1998-11-15

    Modeling the kinetics of protein adsorption at solid surfaces is needed to predict protein separations, design biosensors, and determine the body's initial response to foreign objects. We develop, at the particle level, a kinetic model that accounts geometrically for the surface blockage due to adsorption and postadsorption conformational (or orientational) transitions. Proteins are modeled as disk-shaped particles of diameter final sigmaalpha that adsorb irreversibly at random positions onto a surface at a rate kac (c is the concentration of protein in the bulk solution). Adsorption occurs only where the surface is empty. Following adsorption, a particle attempts to spread (symmetrically) to a larger diameter final sigmabeta at a rate ks. Spreading only occurs if no overlap with any previously placed particle would result. A set of equations is developed for determining the time evolution of the adsorbed protein density. These predictions are compared to new experimental data for fibronectin onto silica-titania obtained using optical waveguide lightmode spectroscopy (OWLS). We also discuss the general application of this model to experimental data. Copyright 1998 Academic Press.

  3. Irreversible thermodynamics of open chemical networks. I. Emergent cycles and broken conservation laws.

    Science.gov (United States)

    Polettini, Matteo; Esposito, Massimiliano

    2014-07-14

    In this paper and Paper II, we outline a general framework for the thermodynamic description of open chemical reaction networks, with special regard to metabolic networks regulating cellular physiology and biochemical functions. We first introduce closed networks "in a box", whose thermodynamics is subjected to strict physical constraints: the mass-action law, elementarity of processes, and detailed balance. We further digress on the role of solvents and on the seemingly unacknowledged property of network independence of free energy landscapes. We then open the system by assuming that the concentrations of certain substrate species (the chemostats) are fixed, whether because promptly regulated by the environment via contact with reservoirs, or because nearly constant in a time window. As a result, the system is driven out of equilibrium. A rich algebraic and topological structure ensues in the network of internal species: Emergent irreversible cycles are associated with nonvanishing affinities, whose symmetries are dictated by the breakage of conservation laws. These central results are resumed in the relation a + b = s(Y) between the number of fundamental affinities a, that of broken conservation laws b and the number of chemostats s(Y). We decompose the steady state entropy production rate in terms of fundamental fluxes and affinities in the spirit of Schnakenberg's theory of network thermodynamics, paving the way for the forthcoming treatment of the linear regime, of efficiency and tight coupling, of free energy transduction, and of thermodynamic constraints for network reconstruction.

  4. Evaluation of irreversible change in brain edema by T1 value

    International Nuclear Information System (INIS)

    Hoshiyama, Minoru; Motegi, Yoshimasa; Furuse, Masahiro; Izawa, Akira; Kanaoke, Yoshiki.

    1990-01-01

    Study of the time course of T 1 value was performed on 6 patients with cerebral infarction, 18 patients with cerebral hemorrhage and 21 patients with cerebral tumor. The measuring points were settled on the ischemic lesions of the cerebral infarctions and the edematous areas of the other intracranial lesions. The T 1 values were calculated from the direct spinlattice relaxation curve by FONAR QED-alpha system (static magnetic field: 433 Gauss). In the acute stage (within 7 days after stroke), more apparent prolongations of T 1 values in infarcted lesions were observed, as compared to the other edematous areas. And in the chronic stage, marked prolongations of T 1 values were recognized on infarcted lesions, often exceeding 1000 msec. From the T 1 values, the water contents of the tissues were calculated by the two state model. The water content of infarcted lesion in acute stage was 86.5%. The water contents of the other edematous areas, on the other, were all under 80%. In the prospect of prognostic values, it is our assumption that, considering that the marked prolongations of the T 1 values on the infarcted lesions are convincingly the tissue degeneration and necrosis, the boundary between the irreversible ischemic change and the edema can be prosumed in the acute stage by T 1 value of about 490 msec, i.e. the water content is about 85%. (author)

  5. Local Control of Perivascular Malignant Liver Lesions Using Percutaneous Irreversible Electroporation: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Eller, Achim, E-mail: Achim.Eller@uk-erlangen.de; Schmid, Axel, E-mail: axel.schmid@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany); Schmidt, Joachim, E-mail: joachim.schmidt@kfa.imed.uni-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Anesthesiology (Germany); May, Matthias, E-mail: matthias.may@uk-erlangen.de; Brand, Michael, E-mail: michael.brand@uk-erlangen.de; Saake, Marc, E-mail: marc.saake@uk-erlangen.de; Uder, Michael, E-mail: michael.uder@uk-erlangen.de; Lell, Michael, E-mail: michael.lell@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany)

    2015-02-15

    PurposeThis study was designed to assess efficacy and safety in the treatment of perivascular malignant liver lesions using percutaneous, computed tomography (CT)-guided irreversible electroporation (IRE).MethodsFourteen patients (mean age 58 ± 11 years) with 18 malignant liver lesions were consecutively enrolled in this study. IRE was performed in patients not eligible for surgery and lesions abutting large vessels or bile ducts. Follow-up exams were performed using multislice-CT (MS-CT) or MRI.ResultsMedium lesion diameter was 20 ± 5 mm. Ten of 14 (71 %) were successfully treated with no local recurrence to date (mean follow-up 388 ± 160 days). One case left initial tumor control unclear and additional RFA was performed 4 weeks after IRE. Complications occurred in 4 of 14 (29 %) cases. In one case, intervention was terminated and abdominal bleeding required laparotomy. In two cases, a postinterventional hematothorax required intervention. In another case, abdominal bleeding could be managed conservatively. No complications related to the bile ducts occurred.ConclusionsPercutaneous IRE seems to be effective in perivascular lesions but is associated with a higher complication rate compared with thermoablative techniques.

  6. Interplay of Determinism and Randomness: From Irreversibility to Chaos, Fractals, and Stochasticity

    Science.gov (United States)

    Tsonis, A.

    2017-12-01

    We will start our discussion into randomness by looking exclusively at our formal mathematical system to show that even in this pure and strictly logical system one cannot do away with randomness. By employing simple mathematical models, we will identify the three possible sources of randomness: randomness due to inability to find the rules (irreversibility), randomness due to inability to have infinite power (chaos), and randomness due to stochastic processes. Subsequently we will move from the mathematical system to our physical world to show that randomness, through the quantum mechanical character of small scales, through chaos, and because of the second law of thermodynamics, is an intrinsic property of nature as well. We will subsequently argue that the randomness in the physical world is consistent with the three sources of randomness suggested from the study of simple mathematical systems. Many examples ranging from purely mathematical to natural processes will be presented, which clearly demonstrate how the combination of rules and randomness produces the world we live in. Finally, the principle of least effort or the principle of minimum energy consumption will be suggested as the underlying principle behind this symbiosis between determinism and randomness.

  7. Irreversible muscle damage in bodybuilding due to long-term intramuscular oil injection.

    Science.gov (United States)

    Banke, I J; Prodinger, P M; Waldt, S; Weirich, G; Holzapfel, B M; Gradinger, R; Rechl, H

    2012-10-01

    Intramuscular oil injections generating slowly degrading oil-based depots represent a controversial subject in bodybuilding and fitness. However they seem to be commonly reported in a large number of non-medical reports, movies and application protocols for 'site-injections'. Surprisingly the impact of long-term (ab)use on the musculature as well as potential side-effects compromising health and sports ability are lacking in the medical literature. We present the case of a 40 year old male semi-professional bodybuilder with systemic infection and painful reddened swellings of the right upper arm forcing him to discontinue weightlifting. Over the last 8 years he daily self-injected sterilized sesame seed oil at numerous intramuscular locations for the purpose of massive muscle building. Whole body MRI showed more than 100 intramuscular rather than subcutaneous oil cysts and loss of normal muscle anatomy. 2-step septic surgery of the right upper arm revealed pus-filled cystic scar tissue with the near-complete absence of normal muscle. MRI 1 year later revealed the absence of relevant muscle regeneration. Persistent pain and inability to perform normal weight training were evident for at least 3 years post-surgery. This alarming finding indicating irreversible muscle mutilation may hopefully discourage people interested in bodybuilding and fitness from oil-injections. The impact of such chronic tissue stress on other diseases like malignancy remains to be determined. © Georg Thieme Verlag KG Stuttgart · New York.

  8. A comprehensive segmentation analysis of crude oil market based on time irreversibility

    Science.gov (United States)

    Xia, Jianan; Shang, Pengjian; Lu, Dan; Yin, Yi

    2016-05-01

    In this paper, we perform a comprehensive entropic segmentation analysis of crude oil future prices from 1983 to 2014 which used the Jensen-Shannon divergence as the statistical distance between segments, and analyze the results from original series S and series begin at 1986 (marked as S∗) to find common segments which have same boundaries. Then we apply time irreversibility analysis of each segment to divide all segments into two groups according to their asymmetry degree. Based on the temporal distribution of the common segments and high asymmetry segments, we figure out that these two types of segments appear alternately and do not overlap basically in daily group, while the common portions are also high asymmetry segments in weekly group. In addition, the temporal distribution of the common segments is fairly close to the time of crises, wars or other events, because the hit from severe events to oil price makes these common segments quite different from their adjacent segments. The common segments can be confirmed in daily group series, or weekly group series due to the large divergence between common segments and their neighbors. While the identification of high asymmetry segments is helpful to know the segments which are not affected badly by the events and can recover to steady states automatically. Finally, we rearrange the segments by merging the connected common segments or high asymmetry segments into a segment, and conjoin the connected segments which are neither common nor high asymmetric.

  9. The effect of small intestine heterogeneity on irreversible electroporation treatment planning.

    Science.gov (United States)

    Phillips, Mary

    2014-09-01

    Nonthermal irreversible electroporation (NTIRE) is an ablation modality that utilizes microsecond electric fields to produce nanoscale defects in the cell membrane. This results in selective cell death while preserving all other molecules, including the extracellular matrix. Here, finite element analysis and experimental results are utilized to examine the effect of NTIRE on the small intestine due to concern over collateral damage to this organ during NTIRE treatment of abdominal cancers. During previous studies, the electrical treatment parameters were chosen based on a simplified homogeneous tissue model. The small intestine, however, has very distinct layers, and a more realistic model is needed to further develop this technology for precise clinical applications. This study uses a two-dimensional finite element solution of the Laplace and heat conduction equations to investigate how small intestine heterogeneities affect the electric field and temperature distribution. Experimental results obtained by applying NTIRE to the rat small intestine in vivo support the heterogeneous effect of NTIRE on the tissue. The numerical modeling indicates that the electroporation parameters chosen for this study avoid thermal damage to the tissue. This is supported by histology obtained from the in vivo study, which showed preservation of extracellular structures. The finite element model also indicates that the heterogeneous structure of the small intestine has a significant effect on the electric field and volume of cell ablation during electroporation and could have a large impact on the extent of treatment. The heterogeneous nature of the tissue should be accounted for in clinical treatment planning.

  10. Impaired Cargo Clearance in the Retinal Pigment Epithelium (RPE Underlies Irreversible Blinding Diseases

    Directory of Open Access Journals (Sweden)

    Eloise Keeling

    2018-02-01

    Full Text Available Chronic degeneration of the Retinal Pigment Epithelium (RPE is a precursor to pathological changes in the outer retina. The RPE monolayer, which lies beneath the neuroretina, daily internalises and digests large volumes of spent photoreceptor outer segments. Impaired cargo handling and processing in the endocytic/phagosome and autophagy pathways lead to the accumulation of lipofuscin and pyridinium bis-retinoid A2E aggregates and chemically modified compounds such as malondialdehyde and 4-hydroxynonenal within RPE. These contribute to increased proteolytic and oxidative stress, resulting in irreversible damage to post-mitotic RPE cells and development of blinding conditions such as age-related macular degeneration, Stargardt disease and choroideremia. Here, we review how impaired cargo handling in the RPE results in their dysfunction, discuss new findings from our laboratory and consider how newly discovered roles for lysosomes and the autophagy pathway could provide insights into retinopathies. Studies of these dynamic, molecular events have also been spurred on by recent advances in optics and imaging technology. Mechanisms underpinning lysosomal impairment in other degenerative conditions including storage disorders, α-synuclein pathologies and Alzheimer’s disease are also discussed. Collectively, these findings help transcend conventional understanding of these intracellular compartments as simple waste disposal bags to bring about a paradigm shift in the way lysosomes are perceived.

  11. Dislocation reactions, grain boundaries, and irreversibility in two-dimensional lattices using topological tweezers.

    Science.gov (United States)

    Irvine, William T M; Hollingsworth, Andrew D; Grier, David G; Chaikin, Paul M

    2013-09-24

    Dislocations, disclinations, and grain boundaries are topological excitations of crystals that play a key role in determining out-of-equilibrium material properties. In this article we study the kinetics, creation, and annihilation processes of these defects in a controllable way by applying "topological tweezers," an array of weak optical tweezers which strain the lattice by weakly pulling on a collection of particles without grabbing them individually. We use topological tweezers to deterministically control individual dislocations and grain boundaries, and reversibly create and destroy dislocation pairs in a 2D crystal of charged colloids. Starting from a perfect lattice, we exert a torque on a finite region and follow the complete step-by-step creation of a disoriented grain, from the creation of dislocation pairs through their reactions to form a grain boundary and their reduction of elastic energy. However, when the grain is rotated back to its original orientation the dislocation reactions do not retrace. Rather, the process is irreversible; the grain boundary expands instead of collapsing.

  12. Modified procedure for secondary facial rehabilitation following total bilateral irreversible peripheral facial palsy.

    Science.gov (United States)

    Barabás, József; Klenk, Gusztáv; Szabó, György; Lukáts, Olga; Bogdán, Sándor; Decker, Iván; Huszár, Tamás

    2007-01-01

    We present the case of a middle-aged gentleman who developed total bilateral irreversible peripheral facial palsy over a period of 10 years, starting with palsy of the marginal mandibular and buccal branches of the facial nerve and progressing to the zygomatic and temporal branches. The patient did not develop any other neurological symptoms, and all neurological and other tests have remained negative over the last 10 years. Dripping of saliva and inability to close the mouth necessitated reanimation of the perioral region with the help of a fascia lata graft fixed to the fascia of the masseter muscles. The increasing lagophthalmos and associated eye problems were alleviated with a temporal muscle transposition combined with a lengthening procedure using the temporal fascia, passed through the upper and lower eyelids and hooked around the medial canthal ligament. The fascia strips were sutured not to the canthal ligament itself, but to each other, thereby placing equal self-adjusted tension on the upper and lower eyelids. Both operations were successful and improved eating and eye closure functions, allowing resolution of the eye symptoms.

  13. A statistical model describing combined irreversible electroporation and electroporation-induced blood-brain barrier disruption.

    Science.gov (United States)

    Sharabi, Shirley; Kos, Bor; Last, David; Guez, David; Daniels, Dianne; Harnof, Sagi; Mardor, Yael; Miklavcic, Damijan

    2016-03-01

    Electroporation-based therapies such as electrochemotherapy (ECT) and irreversible electroporation (IRE) are emerging as promising tools for treatment of tumors. When applied to the brain, electroporation can also induce transient blood-brain-barrier (BBB) disruption in volumes extending beyond IRE, thus enabling efficient drug penetration. The main objective of this study was to develop a statistical model predicting cell death and BBB disruption induced by electroporation. This model can be used for individual treatment planning. Cell death and BBB disruption models were developed based on the Peleg-Fermi model in combination with numerical models of the electric field. The model calculates the electric field thresholds for cell kill and BBB disruption and describes the dependence on the number of treatment pulses. The model was validated using in vivo experimental data consisting of rats brains MRIs post electroporation treatments. Linear regression analysis confirmed that the model described the IRE and BBB disruption volumes as a function of treatment pulses number (r(2) = 0.79; p disruption, the ratio increased with the number of pulses. BBB disruption radii were on average 67% ± 11% larger than IRE volumes. The statistical model can be used to describe the dependence of treatment-effects on the number of pulses independent of the experimental setup.

  14. Analysis and optimization with ecological objective function of irreversible single resonance energy selective electron heat engines

    International Nuclear Information System (INIS)

    Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui

    2016-01-01

    Ecological performance of a single resonance ESE heat engine with heat leakage is conducted by applying finite time thermodynamics. By introducing Nielsen function and numerical calculations, expressions about power output, efficiency, entropy generation rate and ecological objective function are derived; relationships between ecological objective function and power output, between ecological objective function and efficiency as well as between power output and efficiency are demonstrated; influences of system parameters of heat leakage, boundary energy and resonance width on the optimal performances are investigated in detail; a specific range of boundary energy is given as a compromise to make ESE heat engine system work at optimal operation regions. Comparing performance characteristics with different optimization objective functions, the significance of selecting ecological objective function as the design objective is clarified specifically: when changing the design objective from maximum power output into maximum ecological objective function, the improvement of efficiency is 4.56%, while the power output drop is only 2.68%; when changing the design objective from maximum efficiency to maximum ecological objective function, the improvement of power output is 229.13%, and the efficiency drop is only 13.53%. - Highlights: • An irreversible single resonance energy selective electron heat engine is studied. • Heat leakage between two reservoirs is considered. • Power output, efficiency and ecological objective function are derived. • Optimal performance comparison for three objective functions is carried out.

  15. Irreversible splenic atrophy following chronic LCMV infection is associated with compromised immunity in mice.

    Science.gov (United States)

    Mbanwi, Achire N; Wang, Chao; Geddes, Kaoru; Philpott, Dana J; Watts, Tania H

    2017-01-01

    Lymphocytic choriomeningitis virus clone 13 (LCMV13) infection of mice is a widely used model for investigating the mechanisms driving persistent viral infection in humans. LCMV13 disrupts splenic architecture early during infection, but this returns to normal within a few weeks. However, the long-term effects of LCMV13 infection on splenic structure have not been reported. Here, we report that persistent infection with LCMV13 results in sustained splenic atrophy that persists for at least 500 days following infection, whereas infection with the acutely infecting LCMV Armstrong is associated with a return to preinfection spleen weights. Splenic atrophy is associated with loss of T, B, and non-B non-T cells, with B cells most significantly affected. These effects were partly ameliorated by anti-NK1.1 or anti-CD8 antibody treatment. Antigen presentation was detectable at the time of contraction of the spleen, but no longer detected at late time points, suggesting that continued antigen presentation is not required to maintain splenic atrophy. Immunity to Salmonella infection and influenza vaccination were decreased after the virus was no longer detected. Thus splenic atrophy following LCMV13 infection is irreversible and may contribute to impaired immunity following clearance of LCMV13. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Context-aware system for pre-triggering irreversible vehicle safety actuators.

    Science.gov (United States)

    Böhmländer, Dennis; Dirndorfer, Tobias; Al-Bayatti, Ali H; Brandmeier, Thomas

    2017-06-01

    New vehicle safety systems have led to a steady improvement of road safety and a reduction in the risk of suffering a major injury in vehicle accidents. A huge leap forward in the development of new vehicle safety systems are actuators that have to be activated irreversibly shortly before a collision in order to mitigate accident consequences. The triggering decision has to be based on measurements of exteroceptive sensors currently used in driver assistance systems. This paper focuses on developing a novel context-aware system designed to detect potential collisions and to trigger safety actuators even before an accident occurs. In this context, the analysis examines the information that can be collected from exteroceptive sensors (pre-crash data) to predict a certain collision and its severity to decide whether a triggering is entitled or not. A five-layer context-aware architecture is presented, that is able to collect contextual information about the vehicle environment and the actual driving state using different sensors, to perform reasoning about potential collisions, and to trigger safety functions upon that information. Accident analysis is used in a data model to represent uncertain knowledge and to perform reasoning. A simulation concept based on real accident data is introduced to evaluate the presented system concept. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Isothermal chemical denaturation of large proteins: Path-dependence and irreversibility.

    Science.gov (United States)

    Wafer, Lucas; Kloczewiak, Marek; Polleck, Sharon M; Luo, Yin

    2017-12-15

    State functions (e.g., ΔG) are path independent and quantitatively describe the equilibrium states of a thermodynamic system. Isothermal chemical denaturation (ICD) is often used to extrapolate state function parameters for protein unfolding in native buffer conditions. The approach is prudent when the unfolding/refolding processes are path independent and reversible, but may lead to erroneous results if the processes are not reversible. The reversibility was demonstrated in several early studies for smaller proteins, but was assumed in some reports for large proteins with complex structures. In this work, the unfolding/refolding of several proteins were systematically studied using an automated ICD instrument. It is shown that: (i) the apparent unfolding mechanism and conformational stability of large proteins can be denaturant-dependent, (ii) equilibration times for large proteins are non-trivial and may introduce significant error into calculations of ΔG, (iii) fluorescence emission spectroscopy may not correspond to other methods, such as circular dichroism, when used to measure protein unfolding, and (iv) irreversible unfolding and hysteresis can occur in the absence of aggregation. These results suggest that thorough confirmation of the state functions by, for example, performing refolding experiments or using additional denaturants, is needed when quantitatively studying the thermodynamics of protein unfolding using ICD. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effects of design conditions and irreversibilities on the dimensions of ejectors in refrigeration systems

    International Nuclear Information System (INIS)

    Khennich, Mohammed; Galanis, Nicolas; Sorin, Mikhail

    2016-01-01

    Highlights: • New model uses polytropic efficiencies η pol and determines all ejector dimensions. • The effects of η pol on ejector dimensions and mixing efficiency are evaluated. • The effects of inlet/outlet conditions on ejector dimensions are evaluated. • The total exergy losses increase linearly when the mixing efficiency decreases. • Inlet/outlet pressures which reduce exergy losses and total length are determined. - Abstract: A thermodynamic model for the design of ejectors is described, validated and applied for conditions prevailing in refrigeration systems. Contrary to previous models the present one determines all the dimensions of the ejector and uses polytropic (instead of isentropic) efficiencies thus taking into account the effects of the pressure ratio on the entropy increase during the irreversible acceleration and deceleration processes. The results include dimensions and fluid properties for a base case as well as a parametric study which analyzes the effect of inlet and outlet conditions on the dimensions and efficiencies of the acceleration, deceleration and mixing processes. The parametric study coupled to recommended constraints from the literature leads to the determination of design conditions for which the axial evolution of pressure, temperature and velocity are determined. The effects of the polytropic efficiency on the ejector dimensions and the efficiencies of the processes taking place in the ejector are also presented and analysed. It is also shown that the total exergy losses increase linearly when the mixing efficiency decreases.

  19. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia

    International Nuclear Information System (INIS)

    Glavatskiy, K. S.

    2015-01-01

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called “mirror-image” systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval

  20. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia.

    Science.gov (United States)

    Glavatskiy, K S

    2015-10-28

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called "mirror-image" systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval.

  1. Irreversible electroporation and the pancreas: What we know and where we are going?

    Science.gov (United States)

    Young, Shamar J

    2015-08-27

    Pancreatic adenocarcinoma continues to have a poor prognosis with 1 and 5 years survival rates of 27% and 6% respectively. The gold standard of treatment is resection, however, only approximately 10% of patients present with resectable disease. Approximately 40% of patients present with disease that is too locally advanced to resect. There is great interest in improving outcomes in this patient population and ablation techniques have been investigated as a potential solution. Unfortunately early investigations into thermal ablation techniques, particularly radiofrequency ablation, resulted in unacceptably high morbidity rates. Irreversible electroporation (IRE) has been introduced and is promising as it does not rely on thermal energy and has shown an ability to leave structural cells such as blood vessels and bile ducts intact during animal studies. IRE also does not suffer from heat sink effect, a concern given the large number of blood vessels surrounding the pancreas. IRE showed significant promise during preclinical animal trials and as such has moved on to clinical testing. There are as of yet only a few studies which look at the applications of IRE within humans in the setting of pancreatic adenocarcinoma. This paper reviews the basic principles, techniques, and current clinical data available on IRE.

  2. Performance analysis of irreversible quantum Stirling cryogenic refrigeration cycles and their parametric optimum criteria

    International Nuclear Information System (INIS)

    Lin Bihong; Chen Jincan

    2006-01-01

    The influence of both the quantum degeneracy and the finite-rate heat transfer between the working substance and the heat reservoirs on the optimal performance of an irreversible Stirling cryogenic refrigeration cycle using an ideal Fermi or Bose gas as the working substance is investigated, based on the theory of statistical mechanics and thermodynamic properties of ideal quantum gases. The inherent regeneration losses of the cycle are analysed. Expressions for several important performance parameters such as the coefficient of performance, cooling rate and power input are derived. By using numerical solutions, the cooling rate of the cycle is optimized for a given power input. The maximum cooling rate and the corresponding parameters are calculated numerically. The optimal regions of the coefficient of performance and power input are determined. In particular, the optimal performance of the cycle in the strong and weak gas degeneracy cases and the high temperature limit are discussed in detail. The analytic expressions of some optimized parameters are derived. Some optimum criteria are given. The distinctions and connections between the Stirling refrigeration cycles working with the ideal quantum and classical gases are revealed

  3. Porøse materialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2000-01-01

    Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

  4. Irreversibility analysis of non isothermal flat plate solar collectors for air heating with a dimensionless model; Analisis de las irreversibilidades en colectores solares de placas planas no isotermicos para calentamiento de aire utilizando un modelo adimensional

    Energy Technology Data Exchange (ETDEWEB)

    Bracamonte-Baran, Johane Hans; Baritto-Loreto, Miguel Leonardo [Universidad Central de Venezuela (Venezuela)]. E-mails: johanehb@gmail.com; johane.bracamonte@ucv.ve; miguel.baritto@ucv.ve

    2013-04-15

    The dimensionless model developed and validated by Baritto and Bracamonte (2012) for the thermal behavior of flat plate solar collector without glass cover is improved by adding the entropy balance equation in a dimensionless form. The model is solved for a wide range of aspect ratios and mass flow numbers. A parametric study is developed and the distribution of internal irreversibilities along the collector is analyzed. The influence of the design parameters on the entropy generation by fluid friction and heat transfer is analyzed and it is found that for certain combinations of these parameters optimal thermodynamic operation can be achieved. [Spanish] En el presente trabajo, el modelo adimensional desarrollado y validado por Baritto y Bracamonte (2012) para describir el comportamiento termico de colectores solares de placas planas sin cubierta transparente, se complementa con la ecuacion adimensional de balance de entropia para un elemento diferencial de colector solar. El modelo se resuelve para un amplio rango de valores de relaciones de aspecto y numero de flujo de masa. A partir de los resultados del modelo se desarrolla un analisis detallado de la influencia de estos parametros sobre la distribucion de irreversibilidades internas a lo largo del colector. Adicionalmente se estudia la influencia de estos parametros sobre los numeros de generacion de entropia por friccion viscosa, por transferencia de calor y total. Se encuentra que existen combinaciones de los parametros antes mencionados, para los cuales, la operacion del colector es termodinamicamente optima para numeros de flujo de masa elevados.

  5. Use of cadmium in solution in the EL 4 reactor moderator irreversible fixing of cadmium on the metallic surfaces; Utilisation du cadmium en solution dans le moderateur du reacteur EL 4 - fixation irreversible du cadmium sur les surfaces metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Croix, O.; Paoli, O.; Lecomte, J.; Dolle, L.; Gallic, Y. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    In the framework of research into the poisoning of the EL-4 reactor by cadmium sulphate, measurements have been made by two different methods of the residual amounts of cadmium liable to be fixed irreversibly on the surfaces in contact with the heavy water. A marked influence of the pH has been noticed. The mechanism of the irreversible fixing is compatible with the hypothesis of an ion-exchange in the surface oxide layer. In a sufficiently wide range of pH the cadmium thus fixed causes very little residual poisoning. The stability of the cadmium sulphate solutions is however rather low in the conditions of poisoning. (authors) [French] Dans le cadre des etudes sur l'empoisonnement du reacteur EL-4 par le sulfate de cadmium, les quantites residuelles de cadmium susceptibles de se fixer irreversiblement sur les parois que mouillerait l'eau lourde, ont ete mesurees experimentalement par deux methodes differentes. On observe une influence nette du pH. Le mecanisme de la fixation irreversible est compatible avec l'hypothese d'un echange d'ions dans la pellicule d'oxyde superficielle. Dans des limites suffisamment larges de pH, la cadmium ainsi fixe n'occasionne pas d'empoisonnement residuel important. La stabilite des solutions de sulfate de cadmium dans les conditions de l'empoisonnement est cependant mediocre. (auteurs)

  6. Short- and Mid-term Effects of Irreversible Electroporation on Normal Renal Tissue: An Animal Model

    Energy Technology Data Exchange (ETDEWEB)

    Wendler, J. J., E-mail: johann.wendler@med.ovgu.de; Porsch, M.; Huehne, S.; Baumunk, D. [University of Magdeburg, Department of Urology (Germany); Buhtz, P. [Institute of Pathology, University of Magdeburg (Germany); Fischbach, F.; Pech, M. [University of Magdeburg, Department of Radiology (Germany); Mahnkopf, D. [Institute of Medical Technology and Research (Germany); Kropf, S. [Institute of Biometry, University of Magdeburg (Germany); Roessner, A. [Institute of Pathology, University of Magdeburg (Germany); Ricke, J. [University of Magdeburg, Department of Radiology (Germany); Schostak, M.; Liehr, U.-B. [University of Magdeburg, Department of Urology (Germany)

    2013-04-15

    Irreversible electroporation (IRE) is a novel nonthermal tissue ablation technique by high current application leading to apoptosis without affecting extracellular matrix. Previous results of renal IRE shall be supplemented by functional MRI and differentiated histological analysis of renal parenchyma in a chronic treatment setting. Three swine were treated with two to three multifocal percutaneous IRE of the right kidney. MRI was performed before, 30 min (immediate-term), 7 days (short-term), and 28 days (mid-term) after IRE. A statistical analysis of the lesion surrounded renal parenchyma intensities was made to analyze functional differences depending on renal part, side and posttreatment time. Histological follow-up of cortex and medulla was performed after 28 days. A total of eight ablations were created. MRI showed no collateral damage of surrounded tissue. The highest visual contrast between lesions and normal parenchyma was obtained by T2-HR-SPIR-TSE-w sequence of DCE-MRI. Ablation zones showed inhomogeneous necroses with small perifocal edema in the short-term and sharp delimitable scars in the mid-term. MRI showed no significant differences between adjoined renal parenchyma around ablations and parenchyma of untreated kidney. Histological analysis demonstrated complete destruction of cortical glomeruli and tubules, while collecting ducts, renal calyxes, and pelvis of medulla were preserved. Adjoined kidney parenchyma around IRE lesions showed no qualitative differences to normal parenchyma of untreated kidney. This porcine IRE study reveals a multifocal renal ablation, while protecting surrounded renal parenchyma and collecting system over a mid-term period. That offers prevention of renal function ablating centrally located or multifocal renal masses.

  7. Planning Irreversible Electroporation in the Porcine Kidney: Are Numerical Simulations Reliable for Predicting Empiric Ablation Outcomes?

    Energy Technology Data Exchange (ETDEWEB)

    Wimmer, Thomas, E-mail: thomas.wimmer@medunigraz.at; Srimathveeravalli, Govindarajan; Gutta, Narendra [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States); Ezell, Paula C. [The Rockefeller University, Research Animal Resource Center, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College (United States); Monette, Sebastien [The Rockefeller University, Laboratory of Comparative Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College (United States); Maybody, Majid; Erinjery, Joseph P.; Durack, Jeremy C. [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States); Coleman, Jonathan A. [Memorial Sloan-Kettering Cancer Center, Urology Service, Department of Surgery (United States); Solomon, Stephen B. [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States)

    2015-02-15

    PurposeNumerical simulations are used for treatment planning in clinical applications of irreversible electroporation (IRE) to determine ablation size and shape. To assess the reliability of simulations for treatment planning, we compared simulation results with empiric outcomes of renal IRE using computed tomography (CT) and histology in an animal model.MethodsThe ablation size and shape for six different IRE parameter sets (70–90 pulses, 2,000–2,700 V, 70–100 µs) for monopolar and bipolar electrodes was simulated using a numerical model. Employing these treatment parameters, 35 CT-guided IRE ablations were created in both kidneys of six pigs and followed up with CT immediately and after 24 h. Histopathology was analyzed from postablation day 1.ResultsAblation zones on CT measured 81 ± 18 % (day 0, p ≤ 0.05) and 115 ± 18 % (day 1, p ≤ 0.09) of the simulated size for monopolar electrodes, and 190 ± 33 % (day 0, p ≤ 0.001) and 234 ± 12 % (day 1, p ≤ 0.0001) for bipolar electrodes. Histopathology indicated smaller ablation zones than simulated (71 ± 41 %, p ≤ 0.047) and measured on CT (47 ± 16 %, p ≤ 0.005) with complete ablation of kidney parenchyma within the central zone and incomplete ablation in the periphery.ConclusionBoth numerical simulations for planning renal IRE and CT measurements may overestimate the size of ablation compared to histology, and ablation effects may be incomplete in the periphery.

  8. The origin of bore-core remanences: mechanical-shock-imposed irreversible magnetizations

    Science.gov (United States)

    Shi, H.; Tarling, D. H.

    1999-06-01

    Repeated laboratory-induced weak mechanical shocking (c. 0.57 kg m s^- ^1 ) of marine sandstone samples showing drilling-induced remanence, from commercial bore cores from the North Sea and Prudhoe Bay, causes increases in their low-field susceptibility (chi) and their ability to acquire an isothermal remanent magnetization (IRM). These enhancements are reduced by some 20 per cent by AF demagnetization in 100 mT. Doubling the intensity of the shock doubles the susceptibilities and IRMs acquired. The susceptibility increase ceases after 300 to 400 shocks for the North Sea samples and 20 to 30 shocks for those from Prudhoe Bay, while the IRM saturates after 800-1000 and 30-50 shocks respectively. Continental, haematite-bearing sandstones from commercial bore cores with no drilling-induced remanence subjected to the same shocks do not show these effects. Differences in the magnetic mineralogy of shocked and unshocked marine samples suggest that the magnetic enhancement is predominantly due to the creation of pyrrhotite by shock-induced irreversible crystallographic changes in iron-bearing sulphides. When shocked during commercial drilling, these new ferromagnetic minerals acquire strong chemical (crystalline) remanences, associated with a wide spectrum of grain sizes, in the magnetic field of the drill string, and these are resistant to both thermal and AF demagnetization. Similar processes are likely in any situation involving the shock of physically metastable iron-bearing minerals, particularly anoxic sediments. A 5 cm non-magnetic collar between the drill stem and crown should drastically reduce the magnetic intensity of this effect under commercial conditions, but would not prevent its occurrence.

  9. Percutaneous Irreversible Electroporation Lung Ablation: Preliminary Results in a Porcine Model

    International Nuclear Information System (INIS)

    Deodhar, Ajita; Monette, Sébastien; Single, Gordon W.; Hamilton, William C.; Thornton, Raymond H.; Sofocleous, Constantinos T.; Maybody, Majid; Solomon, Stephen B.

    2011-01-01

    Objective: Irreversible electroporation (IRE) uses direct electrical pulses to create permanent “pores” in cell membranes to cause cell death. In contrast to conventional modalities, IRE has a nonthermal mechanism of action. Our objective was to study the histopathological and imaging features of IRE in normal swine lung. Materials and Methods: Eleven female swine were studied for hyperacute (8 h), acute (24 h), subacute (96 h), and chronic (3 week) effects of IRE ablation in lung. Paired unipolar IRE applicators were placed under computed tomography (CT) guidance. Some applicators were deliberately positioned near bronchovascular structures. IRE pulse delivery was synchronized with the cardiac rhythm only when ablation was performed within 2 cm of the heart. Contrast-enhanced CT scan was performed immediately before and after IRE and at 1 and 3 weeks after IRE ablation. Representative tissue was stained with hematoxylin and eosin for histopathology. Results: Twenty-five ablations were created: ten hyperacute, four acute, and three subacute ablations showed alveolar edema and necrosis with necrosis of bronchial, bronchiolar, and vascular epithelium. Bronchovascular architecture was maintained. Chronic ablations showed bronchiolitis obliterans and alveolar interstitial fibrosis. Immediate post-procedure CT images showed linear or patchy density along the applicator tract. At 1 week, there was consolidation that resolved partially or completely by 3 weeks. Pneumothorax requiring chest tube developed in two animals; no significant cardiac arrhythmias were noted. Conclusion: Our preliminary porcine study demonstrates the nonthermal and extracellular matrix sparing mechanism of action of IRE. IRE is a potential alternative to thermal ablative modalities.

  10. Recognition of reversible and irreversible myocardial injury by technetium pyrophosphate extraction kinetics

    International Nuclear Information System (INIS)

    Silva, R.; Chen, Y.F.; Sell, T.L.; Lowe, J.E.; Jones, R.H.

    1987-01-01

    The need for a more accurate method of detecting episodes of myocardial ischemia during cardiac operations, particularly during the ischemic arrest interval, prompted us to investigate the usefulness of measuring the active extraction of technetium pyrophosphate in identifying and quantitating ischemic injury. Twenty-four adult mongrel dogs were subjected to cardiopulmonary bypass, and normothermic global ischemia was induced by cross-clamping the proximal aorta. Technetium pyrophosphate (1 mCi) was injected through a standard cardioplegia line with normal saline, simulating administration of cardioplegic solution, upon placement of the aortic cross-clamp (time 0), at 15, 30, 45, and 60 minutes of global ischemia, and with the onset and completion of ischemic contracture. Radioactive counts were recorded over the heart at 1 second intervals, and the extraction fraction and half-time of clearance were calculated. The extraction fraction increased from 0.22 at time 0 to 0.58 at 15 minutes, 0.82 at 30 minutes, 0.85 at 45 minutes, and 0.91 at 60 minutes. The halftime increased from a baseline of 114 seconds (time 0) to a maximum of 321 seconds at 60 minutes of ischemia. The onset and completion of ischemic contracture showed a return toward baseline of both the extraction fraction and halftime of clearance, with an extraction fraction of 0.44 and 0.46 and a halftime of 135 and 133 seconds, respectively. These data clearly show that reversible myocardial injury increased the extraction and reduced the clearance of technetium pyrophosphate and that the magnitude of change related to the extent of injury. The progression to irreversible myocardial injury decreased the active extraction of technetium pyrophosphate. This simple procedure for real-time documentation of myocardial injury promises to provide easily obtainable endpoints of injury for use during cardiac operations in humans

  11. Computational modeling of the hematopoietic erythroid-myeloid switch reveals insights into cooperativity, priming, and irreversibility.

    Directory of Open Access Journals (Sweden)

    Vijay Chickarmane

    2009-01-01

    Full Text Available Hematopoietic stem cell lineage choices are decided by genetic networks that are turned ON/OFF in a switch-like manner. However, prior to lineage commitment, genes are primed at low expression levels. Understanding the underlying molecular circuitry in terms of how it governs both a primed state and, at the other extreme, a committed state is of relevance not only to hematopoiesis but also to developmental systems in general. We develop a computational model for the hematopoietic erythroid-myeloid lineage decision, which is determined by a genetic switch involving the genes PU.1 and GATA-1. Dynamical models based upon known interactions between these master genes, such as mutual antagonism and autoregulation, fail to make the system bistable, a desired feature for robust lineage determination. We therefore suggest a new mechanism involving a cofactor that is regulated as well as recruited by one of the master genes to bind to the antagonistic partner that is necessary for bistability and hence switch-like behavior. An interesting fallout from this architecture is that suppression of the cofactor through external means can lead to a loss of cooperativity, and hence to a primed state for PU.1 and GATA-1. The PU.1-GATA-1 switch also interacts with another mutually antagonistic pair, C/EBPalpha-FOG-1. The latter pair inherits the state of its upstream master genes and further reinforces the decision due to several feedback loops, thereby leading to irreversible commitment. The genetic switch, which handles the erythroid-myeloid lineage decision, is an example of a network that implements both a primed and a committed state by regulating cooperativity through recruitment of cofactors. Perturbing the feedback between the master regulators and downstream targets suggests potential reprogramming strategies. The approach points to a framework for lineage commitment studies in general and could aid the search for lineage-determining genes.

  12. AGEs/RAGE in CKD: irreversible metabolic memory road toward CVD?

    Science.gov (United States)

    Koyama, Hidenori; Nishizawa, Yoshiki

    2010-07-01

    Cardiovascular disease is the major cause of death in patients with renal insufficiency, accounting for 50% of all deaths in renal replacement therapy patients. Mortality from cardiovascular diseases in these patients is approximately 9% per year, which is about 30 times the risk in the general population. So far, intensive interventions to the general risk factors, such as high LDL-cholesterol or C-reactive protein, have not been successful in improving their cardiovascular outcomes, suggesting that the beneficial effect of risk reduction may be overwhelmed by accumulated risk memorized by long-term exposure to oxidative stress during the progression of renal failure. In this review, we propose that this irreversible memory effect in renal failure may be mediated by advanced glycation end-products (AGEs). The generation of AGEs has been implicated to be deeply associated with increased oxidative stress. Moreover, interaction of the receptor for AGEs (RAGE) with AGEs leads to crucial biomedical pathway generating intracellular oxidative stress and inflammatory mediators, which could result in further amplification of the pathway involved in AGE generation. Several lines of evidence suggest that AGEs/RAGE axis can profoundly be involved in cardiovascular diseases. Recent advances in AGEs and RAGE measurements led us to be capable of understanding more about the role of AGEs/RAGE axis as a risk for cardiovascular diseases in patients with renal failure. AGEs/RAGE axis could be a crucial mediator of oxidative stress in renal failure. RAGE could be not only a useful biomarker, but also a potentially therapeutic target to overcome the accumulated adverse metabolic memory in renal failure.

  13. Further Insight Relative to Cavity Radiation III: Gedanken Experiments, Irreversibility, and Kirchhoff's Law

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2016-01-01

    Full Text Available Recently, gedanken experiments have been proposed in order to examine the validity of Kirchhoff’s Law of Thermal Emission (P.-M. Robitaille, Further Insight Relative to Cavity Radiation: A Thought Experiment Refuting Kirchhoff’s Law, Prog. Phys., 2014, v. 10, no. 1, 38–40; P.-M. Robitaille, Further Insight Relative to Cavity Radiation II: Gedanken Experiments and Kirchhoff’s Law, Prog. Phys., 2014, v. 10, no. 2, 116–120. In the second of these works, real materials (i.e. graphite and silver were utilized in or- der to construct two separate cavities at the same temperature which are then placed in thermal contact with one another. It was hypothesized that the graphite cavity initially contained blackbody radiation and that the silver cavity was devoid of radiation. In the case of the silver cavity, all of the energy of the system was assigned to the phonons in its walls. When the cavities were brought together and a small hole introduced between the cavities, it was hypothesized that thermal contact between the cavity walls would enable the transformation of phonon energy into photon energy, eventually resulting in filling the silver cavity with black radiation. Energy contained within the wall of the silver cavity was believed to be reversibly trapped. However, in allowing energy to flow reversibly out of the walls of the silver cavity in this context, it has been assumed that the silver conduction bands could be neglected and that only phonon energy need be considered. However, the reflectivity attributed to the silver cavity should be con- sidered uniquely as a result of energy associated with the formation of its conduction bands. Such formation must be considered irreversible. It will be demonstrated that under these conditions Kirchhoff’s law, once again, does not hold. The lack of ther- mal radiation within the silver cavity does not lead to a violation of the second law of thermodynamics.

  14. Pain Analysis in Patients with Hepatocellular Carcinoma: Irreversible Electroporation versus Radiofrequency Ablation—Initial Observations

    International Nuclear Information System (INIS)

    Narayanan, Govindarajan; Froud, Tatiana; Lo, Kaming; Barbery, Katuska J.; Perez-Rojas, Evelyn; Yrizarry, Jose

    2013-01-01

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act–compliant, institutional review board–approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher’s exact test, the Chi-square test, and Student’s t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  15. Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction.

    Science.gov (United States)

    Stouthamer, Richard; Russell, James E; Vavre, Fabrice; Nunney, Leonard

    2010-07-28

    The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between cytoplasmic and nuclear genes, and

  16. Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction

    Science.gov (United States)

    2010-01-01

    Background The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. Results The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. Conclusions This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between

  17. Enhancing Irreversible Electroporation by Manipulating Cellular Biophysics with a Molecular Adjuvant.

    Science.gov (United States)

    Ivey, Jill W; Latouche, Eduardo L; Richards, Megan L; Lesser, Glenn J; Debinski, Waldemar; Davalos, Rafael V; Verbridge, Scott S

    2017-07-25

    Pulsed electric fields applied to cells have been used as an invaluable research tool to enhance delivery of genes or other intracellular cargo, as well as for tumor treatment via electrochemotherapy or tissue ablation. These processes involve the buildup of charge across the cell membrane, with subsequent alteration of transmembrane potential that is a function of cell biophysics and geometry. For traditional electroporation parameters, larger cells experience a greater degree of membrane potential alteration. However, we have recently demonstrated that the nuclear/cytoplasm ratio (NCR), rather than cell size, is a key predictor of response for cells treated with high-frequency irreversible electroporation (IRE). In this study, we leverage a targeted molecular therapy, ephrinA1, known to markedly collapse the cytoplasm of cells expressing the EphA2 receptor, to investigate how biophysical cellular changes resulting from NCR manipulation affect the response to IRE at varying frequencies. We present evidence that the increase in the NCR mitigates the cell death response to conventional electroporation pulsed-electric fields (∼100 μs), consistent with the previously noted size dependence. However, this same molecular treatment enhanced the cell death response to high-frequency electric fields (∼1 μs). This finding demonstrates the importance of considering cellular biophysics and frequency-dependent effects in developing electroporation protocols, and our approach provides, to our knowledge, a novel and direct experimental methodology to quantify the relationship between cell morphology, pulse frequency, and electroporation response. Finally, this novel, to our knowledge, combinatorial approach may provide a paradigm to enhance in vivo tumor ablation through a molecular manipulation of cellular morphology before IRE application. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  18. Planning Irreversible Electroporation in the Porcine Kidney: Are Numerical Simulations Reliable for Predicting Empiric Ablation Outcomes?

    International Nuclear Information System (INIS)

    Wimmer, Thomas; Srimathveeravalli, Govindarajan; Gutta, Narendra; Ezell, Paula C.; Monette, Sebastien; Maybody, Majid; Erinjery, Joseph P.; Durack, Jeremy C.; Coleman, Jonathan A.; Solomon, Stephen B.

    2015-01-01

    PurposeNumerical simulations are used for treatment planning in clinical applications of irreversible electroporation (IRE) to determine ablation size and shape. To assess the reliability of simulations for treatment planning, we compared simulation results with empiric outcomes of renal IRE using computed tomography (CT) and histology in an animal model.MethodsThe ablation size and shape for six different IRE parameter sets (70–90 pulses, 2,000–2,700 V, 70–100 µs) for monopolar and bipolar electrodes was simulated using a numerical model. Employing these treatment parameters, 35 CT-guided IRE ablations were created in both kidneys of six pigs and followed up with CT immediately and after 24 h. Histopathology was analyzed from postablation day 1.ResultsAblation zones on CT measured 81 ± 18 % (day 0, p ≤ 0.05) and 115 ± 18 % (day 1, p ≤ 0.09) of the simulated size for monopolar electrodes, and 190 ± 33 % (day 0, p ≤ 0.001) and 234 ± 12 % (day 1, p ≤ 0.0001) for bipolar electrodes. Histopathology indicated smaller ablation zones than simulated (71 ± 41 %, p ≤ 0.047) and measured on CT (47 ± 16 %, p ≤ 0.005) with complete ablation of kidney parenchyma within the central zone and incomplete ablation in the periphery.ConclusionBoth numerical simulations for planning renal IRE and CT measurements may overestimate the size of ablation compared to histology, and ablation effects may be incomplete in the periphery

  19. Short- and Mid-term Effects of Irreversible Electroporation on Normal Renal Tissue: An Animal Model

    International Nuclear Information System (INIS)

    Wendler, J. J.; Porsch, M.; Hühne, S.; Baumunk, D.; Buhtz, P.; Fischbach, F.; Pech, M.; Mahnkopf, D.; Kropf, S.; Roessner, A.; Ricke, J.; Schostak, M.; Liehr, U.-B.

    2013-01-01

    Irreversible electroporation (IRE) is a novel nonthermal tissue ablation technique by high current application leading to apoptosis without affecting extracellular matrix. Previous results of renal IRE shall be supplemented by functional MRI and differentiated histological analysis of renal parenchyma in a chronic treatment setting. Three swine were treated with two to three multifocal percutaneous IRE of the right kidney. MRI was performed before, 30 min (immediate-term), 7 days (short-term), and 28 days (mid-term) after IRE. A statistical analysis of the lesion surrounded renal parenchyma intensities was made to analyze functional differences depending on renal part, side and posttreatment time. Histological follow-up of cortex and medulla was performed after 28 days. A total of eight ablations were created. MRI showed no collateral damage of surrounded tissue. The highest visual contrast between lesions and normal parenchyma was obtained by T2-HR-SPIR-TSE-w sequence of DCE-MRI. Ablation zones showed inhomogeneous necroses with small perifocal edema in the short-term and sharp delimitable scars in the mid-term. MRI showed no significant differences between adjoined renal parenchyma around ablations and parenchyma of untreated kidney. Histological analysis demonstrated complete destruction of cortical glomeruli and tubules, while collecting ducts, renal calyxes, and pelvis of medulla were preserved. Adjoined kidney parenchyma around IRE lesions showed no qualitative differences to normal parenchyma of untreated kidney. This porcine IRE study reveals a multifocal renal ablation, while protecting surrounded renal parenchyma and collecting system over a mid-term period. That offers prevention of renal function ablating centrally located or multifocal renal masses.

  20. An experimental and numerical investigation of phase change electrodes for therapeutic irreversible electroporation.

    Science.gov (United States)

    Arena, Christopher B; Mahajan, Roop L; Nichole Rylander, Marissa; Davalos, Rafael V

    2013-11-01

    Irreversible electroporation (IRE) is a new technology for ablating aberrant tissue that utilizes pulsed electric fields (PEFs) to kill cells by destabilizing their plasma membrane. When treatments are planned correctly, the pulse parameters and location of the electrodes for delivering the pulses are selected to permit destruction of the target tissue without causing thermal damage to the surrounding structures. This allows for the treatment of surgically inoperable masses that are located near major blood vessels and nerves. In select cases of high-dose IRE, where a large ablation volume is desired without increasing the number of electrode insertions, it can become challenging to design a pulse protocol that is inherently nonthermal. To solve this problem we have developed a new electrosurgical device that requires no external equipment or protocol modifications. The design incorporates a phase change material (PCM) into the electrode core that melts during treatment and absorbs heat out of the surrounding tissue. Here, this idea is reduced to practice by testing hollow electrodes filled with gallium on tissue phantoms and monitoring temperature in real time. Additionally, the experimental data generated are used to validate a numerical model of the heat transfer problem, which is then applied to investigate the cooling performance of other classes of PCMs. The results indicate that metallic PCMs, such as gallium, are better suited than organics or salt hydrates for thermal management, because their comparatively higher thermal conductivity aids in heat dissipation. However, the melting point of the metallic PCM must be properly adjusted to ensure that the phase transition is not completed before the end of treatment. When translated clinically, phase change electrodes have the potential to continue to allow IRE to be performed safely near critical structures, even in high-dose cases.

  1. A Major Role for Side-Chain Polyglutamine Hydrogen Bonding in Irreversible Ataxin-3 Aggregation

    Science.gov (United States)

    Relini, Annalisa; Apicella, Alessandra; Invernizzi, Gaetano; Casari, Carlo; Gliozzi, Alessandra; Doglia, Silvia Maria; Tortora, Paolo; Regonesi, Maria Elena

    2011-01-01

    The protein ataxin-3 consists of an N-terminal globular Josephin domain (JD) and an unstructured C-terminal region containing a stretch of consecutive glutamines that triggers the neurodegenerative disorder spinocerebellar ataxia type 3, when it is expanded beyond a critical threshold. The disease results from misfolding and aggregation, although the pathway and structure of the aggregation intermediates are not fully understood. In order to provide insight into the mechanism of the process, we monitored the aggregation of a normal (AT3Q24) ataxin-3, an expanded (AT3Q55) ataxin-3, and the JD in isolation. We observed that all of them aggregated, although the latter did so at a much slower rate. Furthermore, the expanded AT3Q55 displayed a substantially different behavior with respect to the two other variants in that at the latest stages of the process it was the only one that did the following: i) lost its reactivity towards an anti-oligomer antibody, ii) generated SDS-insoluble aggregates, iii) gave rise to bundles of elongated fibrils, and iv) displayed two additional bands at 1604 and 1656 cm−1 in FTIR spectroscopy. Although these were previously observed in other aggregated polyglutamine proteins, no one has assigned them unambiguously, yet. By H/D exchange experiments we show for the first time that they can be ascribed to glutamine side-chain hydrogen bonding, which is therefore the hallmark of irreversibly SDS-insoluble aggregated protein. FTIR spectra also showed that main-chain intermolecular hydrogen bonding preceded that of glutamine side-chains, which suggests that the former favors the latter by reorganizing backbone geometry. PMID:21533208

  2. A major role for side-chain polyglutamine hydrogen bonding in irreversible ataxin-3 aggregation.

    Directory of Open Access Journals (Sweden)

    Antonino Natalello

    2011-04-01

    Full Text Available The protein ataxin-3 consists of an N-terminal globular Josephin domain (JD and an unstructured C-terminal region containing a stretch of consecutive glutamines that triggers the neurodegenerative disorder spinocerebellar ataxia type 3, when it is expanded beyond a critical threshold. The disease results from misfolding and aggregation, although the pathway and structure of the aggregation intermediates are not fully understood. In order to provide insight into the mechanism of the process, we monitored the aggregation of a normal (AT3Q24 ataxin-3, an expanded (AT3Q55 ataxin-3, and the JD in isolation. We observed that all of them aggregated, although the latter did so at a much slower rate. Furthermore, the expanded AT3Q55 displayed a substantially different behavior with respect to the two other variants in that at the latest stages of the process it was the only one that did the following: i lost its reactivity towards an anti-oligomer antibody, ii generated SDS-insoluble aggregates, iii gave rise to bundles of elongated fibrils, and iv displayed two additional bands at 1604 and 1656 cm(-1 in FTIR spectroscopy. Although these were previously observed in other aggregated polyglutamine proteins, no one has assigned them unambiguously, yet. By H/D exchange experiments we show for the first time that they can be ascribed to glutamine side-chain hydrogen bonding, which is therefore the hallmark of irreversibly SDS-insoluble aggregated protein. FTIR spectra also showed that main-chain intermolecular hydrogen bonding preceded that of glutamine side-chains, which suggests that the former favors the latter by reorganizing backbone geometry.

  3. Evaluation of resistance as a measure of successful tumor ablation during irreversible electroporation of the pancreas.

    Science.gov (United States)

    Dunki-Jacobs, Erik M; Philips, Prejesh; Martin, Robert C G

    2014-02-01

    Intraoperative evaluation of successful pancreatic tumor ablation using irreversible electroporation (IRE) is difficult secondary to lack of visual confirmation. The IRE generator provides feedback by reporting current (amperage), which can be used to calculate changes in tumor tissue resistance. The purpose of the study was to determine if resistance can be used to predict successful tumor ablation during IRE for pancreatic cancers. All patients undergoing pancreatic IRE from March 2010 to December 2012 were evaluated using a prospective database. Intraoperative information, including change in tumor resistance during ablation and slope of the resistance curve, were used to evaluate effectiveness of tumor ablation in terms of local failure or recurrence (LFR) and disease-free survival (DFS). A total of 65 patients underwent IRE for locally advanced pancreatic cancer. Median follow-up was 23 months. Local failure or recurrence was seen in 17 patients at 3, 6, or 9 months post IRE. Change in tumor tissue resistance and the slope of the resistance curve were both significant in predicting LFR (p = 0.02 and p = 0.01, respectively). The median local disease-free survival was 5.5 months in patients who had recurrence compared with 12.6 months in patients who did not recur (p = 0.03). Neither mean change in tumor tissue resistance nor the slope of the resistance curve significantly predicted overall DFS. Mean change in tumor tissue resistance and the slope of the resistance curve could be used intraoperatively to assess successful tumor ablation during IRE. Larger sample size and longer follow-up are needed to determine if these parameters can be used to predict DFS. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  4. Palmitoylation of caveolin-1 in endothelial cells is post-translational but irreversible

    Science.gov (United States)

    Parat, M. O.; Fox, P. L.

    2001-01-01

    Caveolin-1 is a palmitoylated protein involved in assembly of signaling molecules in plasma membrane subdomains termed caveolae and in intracellular cholesterol transport. Three cysteine residues in the C terminus of caveolin-1 are subject to palmitoylation, which is not necessary for caveolar targeting of caveolin-1. Protein palmitoylation is a post-translational and reversible modification that may be regulated and that in turn may regulate conformation, membrane association, protein-protein interactions, and intracellular localization of the target protein. We have undertaken a detailed analysis of [(3)H]palmitate incorporation into caveolin-1 in aortic endothelial cells. The linkage of palmitate to caveolin-1 was hydroxylamine-sensitive and thus presumably a thioester bond. However, contrary to expectations, palmitate incorporation was blocked completely by the protein synthesis inhibitors cycloheximide and puromycin. In parallel experiments to show specificity, palmitoylation of aortic endothelial cell-specific nitric-oxide synthase was unaffected by these reagents. Inhibitors of protein trafficking, brefeldin A and monensin, blocked caveolin-1 palmitoylation, indicating that the modification was not cotranslational but rather required caveolin-1 transport from the endoplasmic reticulum and Golgi to the plasma membrane. In addition, immunophilin chaperones that form complexes with caveolin-1, i.e. FK506-binding protein 52, cyclophilin A, and cyclophilin 40, were not necessary for caveolin-1 palmitoylation because agents that bind immunophilins did not inhibit palmitoylation. Pulse-chase experiments showed that caveolin-1 palmitoylation is essentially irreversible because the release of [(3)H]palmitate was not significant even after 24 h. These results show that [(3)H]palmitate incorporation is limited to newly synthesized caveolin-1, not because incorporation only occurs during synthesis but because the continuous presence of palmitate on caveolin-1 prevents

  5. Irreversibility of T-Cell Specification: Insights from Computational Modelling of a Minimal Network Architecture.

    Directory of Open Access Journals (Sweden)

    Erica Manesso

    Full Text Available A cascade of gene activations under the control of Notch signalling is required during T-cell specification, when T-cell precursors gradually lose the potential to undertake other fates and become fully committed to the T-cell lineage. We elucidate how the gene/protein dynamics for a core transcriptional module governs this important process by computational means.We first assembled existing knowledge about transcription factors known to be important for T-cell specification to form a minimal core module consisting of TCF-1, GATA-3, BCL11B, and PU.1 aiming at dynamical modeling. Model architecture was based on published experimental measurements of the effects on each factor when each of the others is perturbed. While several studies provided gene expression measurements at different stages of T-cell development, pure time series are not available, thus precluding a straightforward study of the dynamical interactions among these genes. We therefore translate stage dependent data into time series. A feed-forward motif with multiple positive feed-backs can account for the observed delay between BCL11B versus TCF-1 and GATA-3 activation by Notch signalling. With a novel computational approach, all 32 possible interactions among Notch signalling, TCF-1, and GATA-3 are explored by translating combinatorial logic expressions into differential equations for BCL11B production rate.Our analysis reveals that only 3 of 32 possible configurations, where GATA-3 works as a dimer, are able to explain not only the time delay, but very importantly, also give rise to irreversibility. The winning models explain the data within the 95% confidence region and are consistent with regard to decay rates.This first generation model for early T-cell specification has relatively few players. Yet it explains the gradual transition into a committed state with no return. Encoding logics in a rate equation setting allows determination of binding properties beyond what is

  6. Pain Analysis in Patients with Hepatocellular Carcinoma: Irreversible Electroporation versus Radiofrequency Ablation-Initial Observations

    Energy Technology Data Exchange (ETDEWEB)

    Narayanan, Govindarajan, E-mail: gnarayanan@med.miami.edu; Froud, Tatiana, E-mail: tfroud@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States); Lo, Kaming, E-mail: KLo@biostat.med.miami.edu [Miller School of Medicine, University of Miami, Department of Epidemiology and Public Health (United States); Barbery, Katuska J., E-mail: kbarbery@med.miami.edu; Perez-Rojas, Evelyn, E-mail: eprojas@med.miami.edu; Yrizarry, Jose, E-mail: jyrizarr@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States)

    2013-02-15

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  7. Pain analysis in patients with hepatocellular carcinoma: irreversible electroporation versus radiofrequency ablation-initial observations.

    Science.gov (United States)

    Narayanan, Govindarajan; Froud, Tatiana; Lo, Kaming; Barbery, Katuska J; Perez-Rojas, Evelyn; Yrizarry, Jose

    2013-02-01

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  8. Implications and considerations of thermal effects when applying irreversible electroporation tissue ablation therapy.

    Science.gov (United States)

    Davalos, Rafael V; Bhonsle, Suyashree; Neal, Robert E

    2015-07-01

    Irreversible electroporation (IRE) describes a cellular response to electric field exposure, resulting in the formation of nanoscale defects that can lead to cell death. While this behavior occurs independently of thermally-induced processes, therapeutic ablation of targeted tissues with IRE uses a series of brief electric pulses, whose parameters result in secondary Joule heating of the tissue. Where contemporary clinical pulse protocols use aggressive energy regimes, additional evidence is supplementing original studies that assert care must be taken in clinical ablation protocols to ensure the cumulative thermal effects do not induce damage that will alter outcomes for therapies using the IRE non-thermal cell death process for tissue ablation. In this letter, we seek to clarify the nomenclature regarding IRE as a non-thermal ablation technique, as well as identify existing literature that uses experimental, clinical, and numerical results to discretely address and evaluate the thermal considerations relevant when applying IRE in clinical scenarios, including several approaches for reducing these effects. Existing evidence in the literature describes cell response to electric fields, suggesting cell death from IRE is a unique process, independent from traditional thermal damage. Numerical simulations, as well as preclinical and clinical findings demonstrate the ability to deliver therapeutic IRE ablation without occurrence of morbidity associated with thermal therapies. Clinical IRE therapy generates thermal effects, which may moderate the non-thermal aspects of IRE ablation. Appropriate protocol development, utilization, and pulse delivery devices may be implemented to restrain these effects and maintain IRE as the vastly predominant tissue death modality, reducing therapy-mitigating thermal damage. Clinical applications of IRE should consider thermal effects and employ protocols to ensure safe and effective therapy delivery. © 2015 The Authors. The Prostate

  9. Optimal performance at arbitrary power of minimally nonlinear irreversible thermoelectric generators with broken time-reversal symmetry

    Science.gov (United States)

    Zhang, Rong; Liu, Wei; Li, Qianwen; Zhang, Lei; Bai, Long

    2018-01-01

    We investigate the performance at arbitrary power of minimally nonlinear irreversible thermoelectric generators (MNITGs) with broken time-reversal symmetry within linear irreversible thermodynamics, and the efficiency of MNITGs at arbitrary power is analytically derived. Furthermore, a universal bound on the efficiency of thermoelectric generators (TGs) with broken time-reversal symmetry and the arbitrary power is obtained. Some system-specific characteristics are discussed and uncovered. A large efficiency at arbitrary power can also be achieved via the cooperative mechanism between the system parameters. Our results indicate that the broken time-reversal symmetry provides the physically allowed degrees of freedom for tuning the performance of thermoelectric devices, and the physical trade-off region between the efficiency and the power output can also offer the appropriate space for optimizing the performance of TGs.

  10. Effect of long acting local anesthetic on postoperative pain in teeth with irreversible pulpitis: Randomized clinical trial

    Science.gov (United States)

    Al-Kahtani, Ahmed

    2013-01-01

    Objective The objective of this study was to compare the effect of long acting anesthetics on postoperative pain in teeth with irreversible pulpitis. Methodology Forty patients were randomly assigned into two groups of twenty patients each. Each patient who fit the inclusion criteria was administered local anesthesia before undergoing root canal treatment. The anesthetic solution was either 2% lidocaine with 1:80,000 epinephrine or 0.5% bupivacaine with 1:200,000 epinephrine. Patients were instructed to complete a VAS pain score at 6, 12, 24 h after single visit root canal treatment. Data were analyzed by Mann–Whitney, Cochrane Q analysis and t test to compare qualitative and quantitative data between the groups. Results The results showed the levels of pain of the patients who received lidocaine as the anesthetic agent and had significantly more postoperative pain after root canal treatment (P irreversible pulpitis. PMID:24493972

  11. Measurement of local blood flow and oxygen consumption in evolving irreversible cerebral infarction: an in vivo study in man

    International Nuclear Information System (INIS)

    Baron, J.C.; Rougemont, D.; Lebrun-Grandie, P.; Bousser, M.G.; Cabanis, E.; Bories, J.; Comar, D.; Castaigne, P.

    1982-09-01

    Positron emission tomography (PET) allows in vivo measurement of local cerebral blood flow (1CBF), oxygen consumption rate (1CMRO 2 ) and glucose utilisation (1CMRG1c) in man. Although 1CMRG1c is accessible in animals, this is not the case for 1CMRO 2 , an excellent index of local functional state. PET imaging of the local interrelationship of CBF and metabolism in completed ischemic stroke has attracted considerable interest because of its potential to differentiate irreversibly damaged from viable tissue on the basis of the CBF- metabolism patterns. Several qualitative or semi-quantitative pioneering studies provided a limited insight into this question, while the single truly quantitative study was only briefly reported. We report here a detailed study of the local CBF-CMRO 2 quantitative patterns in irreversibly infarcted brain regions

  12. Mineral trioxide aggregate pulpotomy for permanent molars with clinical signs indicative of irreversible pulpitis: a preliminary study.

    Science.gov (United States)

    Qudeimat, M A; Alyahya, A; Hasan, A A

    2017-02-01

    To prospectively investigate the clinical and radiographic success rates of pulpotomy in permanent molars with clinical signs and symptoms suggestive of irreversible pulpitis using mineral trioxide aggregate (MTA) as a pulp dressing agent. Sixteen patients with 23 restorable permanent molars exhibiting signs and symptoms indicative of irreversible pulpitis were enrolled. A standardized operative procedure was followed for all participants. All teeth were isolated with a dental dam and caries was removed, and then, pulpotomy performed with a sterile round and/or flame shape diamond burs. Haemostasis was achieved with 5% sodium hypochlorite (NaOCl). A mixture of MTA was placed against the wound, and a moistened cotton pellet was placed over the MTA. Teeth were temporized with a glass-ionomer restoration. Three to ten days later, the interim restoration was removed and setting of MTA was evaluated. Teeth were restored with stainless steel crowns. Follow-up evaluations were scheduled at 3, 6, 12 months and annually thereafter. Descriptive statistics were used to assess outcomes. The age of patients at time of pulpotomy ranged between 7.6 and 13.6 years (mean = 10.7± 1.7 yrs). The majority of teeth (91%) had clinical signs and symptoms consistent with a diagnosis of symptomatic irreversible pulpitis and symptomatic apical periodontitis (78%). The follow-up examination period ranged from 18.9 to 73.6 months. Clinically and radiographically, all pulpotomies were considered successful at the end of the follow-up period. Radiographically, a hard tissue barrier was noticed in 13 (57%) teeth. In children, MTA was associated with high clinical and radiographic success as a pulpotomy agent in permanent teeth with clinical signs and symptoms suggestive of irreversible pulpitis. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  13. Buffered Lidocaine With Sodium Bicarbonate did not Increase Inferior Alveolar Nerve Block Success Rate in Patients Having Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Parirokh, Masoud

    2016-03-01

    Effect of buffered 4% lidocaine on the success of the inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: a prospective, randomized, double-blind study. Schellenberg J, Drum M, Reader A, Nusstein J, Fowler S, Beck M. J Endod 2015;41(6):791-6. The study was supported by Meyers/Reader Graduate Endodontic Support Fund Double blinded randomized controlled trial. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Electro-Kinetic Pumping with Slip Irreversibility in Heat Exchange of CSP-Powered Bio-Digester Assemblies

    OpenAIRE

    Ogedengbe, Emmanuel; Rosen, Marc

    2012-01-01

    Parametric studies of the effects of slip irreversibility in concentrating solar power (CSP)-powered bio-digester assemblies are investigated. Complexities regarding the identification of the appropriate electro-kinetic phenomena for certain electrolyte phases are reviewed. The application of exergy analysis to the design of energy conversion devices, like solar thermal collectors, for the required heat of formation in a downdraft waste food bio-digester, is discussed. Thermal management in t...

  15. The first step of hen egg white lysozyme fibrillation, irreversible partial unfolding, is a two-state transition

    OpenAIRE

    Xu, Ming; Shashilov, Victor A.; Ermolenkov, Vladimir V.; Fredriksen, Laura; Zagorevski, Dmitri; Lednev, Igor K.

    2007-01-01

    Amyloid fibril depositions are associated with many neurodegenerative diseases as well as amyloidosis. The detailed molecular mechanism of fibrillation is still far from complete understanding. In our previous study of in vitro fibrillation of hen egg white lysozyme, an irreversible partially unfolded intermediate was characterized. A similarity of unfolding kinetics found for the secondary and tertiary structure of lysozyme using deep UV resonance Raman (DUVRR) and tryptophan fluorescence sp...

  16. The effect of pouring time on the dimensional accuracy of casts made from different irreversible hydrocolloid impression materials

    Directory of Open Access Journals (Sweden)

    Supneet Singh Wadhwa

    2013-01-01

    Full Text Available Aims and Objectives: To determine the time dependent accuracy of casts made from three different irreversible hydrocolloids. Materials and Methods: The effect of delayed pouring on the accuracy of three different irreversible hydrocolloid impression materials - Regular set CA 37(Cavex, The Netherlands, regular set chromatic (Jeltrate, Dentsply, and fast set (Hydrogum soft, Zhermack Clinical was investigated. A brass master die that contained two identical posts simulating two complete crown-tapered abutment preparations with reference grooves served as a standardized master model. A total of 120 impressions were made using specially prepared stock-perforated brass tray with 40 impressions of each material. The impressions were further sub-grouped according to four different storage time intervals: 0 min (immediately, 12 min, 30 min, and 1 h. The impressions were stored at room temperature in a zip-lock plastic bag. Interabutment and intraabutment distances were measured in the recovered stone dies (Type IV, Kalrock using a profile projector with an accuracy of 0.001 mm. The data so obtained was analyzed statistically. Results: Results of this study showed no statistically significant differences in the accuracy of casts obtained at different time intervals. Conclusion: Because it is not always possible to pour the impression immediately in routine clinical practice, all irreversible hydrocolloid materials studied could be stored in a zip-lock plastic bag for upto 1 h without any significant distortion.

  17. Irreversible inhibition of RANK expression as a possible mechanism for IL-3 inhibition of RANKL-induced osteoclastogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Khapli, Shruti M.; Tomar, Geetanjali B.; Barhanpurkar, Amruta P.; Gupta, Navita; Yogesha, S.D.; Pote, Satish T. [National Center for Cell Science, University of Pune Campus, Pune 411 007 (India); Wani, Mohan R., E-mail: mohanwani@nccs.res.in [National Center for Cell Science, University of Pune Campus, Pune 411 007 (India)

    2010-09-03

    Research highlights: {yields} IL-3 inhibits receptor activator of NF-{kappa}B ligand (RANKL)-induced osteoclastogenesis. {yields} IL-3 inhibits RANKL-induced JNK activation. {yields} IL-3 down-regulates expression of c-Fos and NFATc1 transcription factors. {yields} IL-3 down-regulates RANK expression posttranscriptionally and irreversibly. {yields} IL-3 inhibits in vivo RANK expression. -- Abstract: IL-3, a cytokine secreted by activated T lymphocytes, stimulates the proliferation, differentiation and survival of pluripotent hematopoietic stem cells. In this study, we investigated the mechanism of inhibitory action of IL-3 on osteoclast differentiation. We show here that IL-3 significantly inhibits receptor activator of NF-{kappa}B (RANK) ligand (RANKL)-induced activation of c-Jun N-terminal kinase (JNK). IL-3 down-regulates expression of c-Fos and nuclear factor of activated T cells (NFATc1) transcription factors. In addition, IL-3 down-regulates RANK expression posttranscriptionally in both purified osteoclast precursors and whole bone marrow cells. Furthermore, the inhibitory effect of IL-3 on RANK expression was irreversible. Interestingly, IL-3 inhibits in vivo RANK expression in mice. Thus, we provide the first evidence that IL-3 irreversibly inhibits RANK expression that results in inhibition of important signaling molecules induced by RANKL.

  18. A Comparison of Different Volumes of Articaine for Inferior Alveolar Nerve Block for Molar Teeth with Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Abazarpoor, Ramin; Parirokh, Masoud; Nakhaee, Nouzar; Abbott, Paul V

    2015-09-01

    Achieving anesthesia in mandibular molar teeth with irreversible pulpitis is very difficult. The aim of this study was to compare the efficacy of 1.8 mL and 3.6 mL articaine for an inferior alveolar nerve block (IANB) when treating molars with symptomatic irreversible pulpitis. In a randomized, double-blind clinical trial, 82 first mandibular molar teeth with symptomatic irreversible pulpitis randomly received conventional IANB injection either with 1 (1.8 mL) or 2 cartridges (3.6 mL) of 4% articaine with 1:100,000 epinephrine. The patients recorded their pain before and during access cavity preparation as well as during root canal instrumentation using a Heft-Parker visual analog scale. No or mild pain was considered as successful anesthesia. Data were analyzed by t and chi-square tests. Eighty patients were eligible to participate in this study, which showed that 3.6 mL articaine provided a significantly higher success rate (77.5%) of IANBs compared with 1.8 mL of the same anesthetic solution (27.5%) although neither group had 100% successful anesthesia (P pulpitis, but it did not result in 100% anesthetic success. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Pain Reduction in Untreated Symptomatic Irreversible Pulpitis Using Liposomal Bupivacaine (Exparel): A Prospective, Randomized, Double-blind Trial.

    Science.gov (United States)

    Bultema, Kristy; Fowler, Sara; Drum, Melissa; Reader, Al; Nusstein, John; Beck, Mike

    2016-12-01

    In the treatment of patients with symptomatic irreversible pulpitis, endodontic debridement is a predictable method to relieve pain. However, there are clinical situations in which emergency care cannot be provided immediately. An unexplored treatment option in these cases may be the use of a long-acting anesthetic to reduce pain in untreated irreversible pulpitis. Some medical studies have shown potential for infiltrations of liposomal bupivacaine (Exparel; Pacira Pharmaceuticals, San Diego, CA) to prolong pain relief and reduce opioid use postoperatively. The Food and Drug Administration has approved Exparel only for infiltrations; therefore, the purpose of this study was to compare an infiltration of liposomal bupivacaine versus bupivacaine for pain control in untreated, symptomatic irreversible pulpitis. Ninety-five emergency patients received 2% lidocaine with 1:100,000 epinephrine via infiltration or an inferior alveolar nerve block to relieve their initial presenting pain. Patients then randomly received either 4 mL liposomal bupivacaine (13.3 mg/mL) or 4 mL 0.5% bupivacaine with 1:200,000 epinephrine by infiltration. Patients received a diary for the day of the appointment and 3 days postinjection to record soft tissue numbness, pain levels, and analgesic (non-narcotic and narcotic) use. No significant differences (P pulpitis. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Comparison of the anesthetic efficacy between bupivacaine and lidocaine in patients with irreversible pulpitis of mandibular molar.

    Science.gov (United States)

    Sampaio, Roberta Moura; Carnaval, Talita Girio; Lanfredi, Camila Bernardeli; Horliana, Anna Carolina Ratto Tempestini; Rocha, Rodney Garcia; Tortamano, Isabel Peixoto

    2012-05-01

    The purpose of this study was to compare the anesthetic efficacy of 0.5% bupivacaine with 1:200,000 epinephrine with that of 2% lidocaine with 1:100,000 epinephrine during pulpectomy in patients with irreversible pulpitis in mandibular posterior teeth. Seventy volunteers, patients with irreversible pulpitis admitted to the Emergency Center of the School of Dentistry at the University of São Paulo, randomly received a conventional inferior alveolar nerve block containing 3.6 mL of either 0.5% bupivacaine with 1:200,000 epinephrine or 2% lidocaine with 1:100,000 epinephrine. During the subsequent pulpectomy, we recorded the patients' subjective assessments of lip anesthesia, the absence/presence of pulpal anesthesia through electric pulp stimulation, and the absence/presence of pain through a verbal analog scale. All patients reported lip anesthesia after the application of either inferior alveolar nerve block. By measuring pulpal anesthesia success with the pulp tester, lidocaine had a higher success rate (42.9%) than bupivacaine (20%). For patients reporting none or mild pain during pulpectomy, the success rate of bupivacaine was 80% and lidocaine was 62.9%. There were only statistically significant differences to the success of pulpal anesthesia. Neither of the solutions resulted in an effective pain control during irreversible pulpitis treatments of mandibular molars. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.