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  • Selected Abstracts


    Extrapolation of the W7-X Magnet System to Reactor Size

    CONTRIBUTIONS TO PLASMA PHYSICS, Issue 8 2010
    F. Schauer
    Abstract The fusion experiment Wendelstein 7-X (W7-X), presently under construction at the Greifswald branch institute of IPP, shall demonstrate the reactor potential of a HELIAS stellarator. HELIAS reactors with three, four and five periods have been studied at IPP since many years. With a plasma axis induction of 5 T, corresponding to about 10 T maximal induction at the coil, it was shown that such reactors are feasible. Now the possibility is being investigated to increase the conductor induction up to the 12 T , range, corresponding to > 5.5 T at the plasma axis. This improves the stellarator confinement properties but does not change the basic physics with respect to the previously analyzed machines. In particular the 5periodic HELIAS type, HSR5, is considered which evolves from W7-X by linear scaling of the main dimensions by a factor of four. Recent progress in superconductor technology and the extensive development work performed for ITER are taken into account. The latter is particularly relevant since by coincidence the circumferences of the HSR5 and the ITER toroidal field coils are practically the same. For the presented 12 T reactor version, the HSR50a, also the conductor and structural requirements are comparable to the corresponding ITER specifications. Therefore, advantage can be taken of these similarities for the stellarator reactor magnet design. The input was provided by the new code "MODUCO" which was developed for interactive coil layout. It is based on Bézier curve approximations and includes the computation of magnetic surfaces and forces (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Evaluation of radiographs, clinical signs and symptoms associated with pulp canal obliteration: an aid to treatment decision

    DENTAL TRAUMATOLOGY, Issue 6 2009
    Adeleke O. Oginni
    The dental clinician faced with this condition has to make a difficult decision. The aim of this study was to evaluate the clinical signs and symptoms associated with teeth with PCO and to assess the status of the periapical tissues using the periapical index (PAI) as an aid in making a treatment decision. The study included teeth diagnosed with PCO in patients with a history of traumatic injury to the involved teeth. Histories of associated signs and symptoms including pain, swelling and drainage from a sinus tract were elicited. Tooth color, sensibility to electric pulp testing, mobility and percussion tenderness were recorded. The periapical status was assessed using the PAI. Two hundred and seventy-six teeth were diagnosed with PCO. One hundred and fifty-seven (56.9%) and 119 (43.1%) demonstrated partial or total PCO, respectively. Yellow discoloration presented most frequently, occurring in 186 (67.4%) teeth. Sixty-two (33.3%) of these had developed periapical lesions and reacted negatively to sensibility testing. Fifty-seven (30.7%) of these teeth presented radiographically with a normal periapical appearance and reacted normally to sensibility testing, whereas 67 (36.0%) presented with small changes in the periapical bone pattern and reacted in the high normal range to sensibility testing. Teeth with PAI scores ,2 presented with occasional spontaneous pain. Teeth with PAI scores ,3 presented with clinical symptoms and signs ranging from pain on percussion to spontaneous pain, and slight swelling to sinus tract drainage. Based on the findings of this study, endodontic treatment should be initiated in teeth with tenderness to percussion, PAI scores ,3 and a negative response to sensibility testing. [source]


    The prevalence of traumatic injuries treated in the pedodontic clinic of Ankara University, Turkey, during 18 months

    DENTAL TRAUMATOLOGY, Issue 6 2002

    Abstract , , ,The purpose of this study was to evaluate the type and prevalence of dental injuries referred to Ankara University, School of Dentistry, Department of Pedodontics, Turkey. One hundred and forty-seven patients with 234 traumatized teeth presented during 18-month interval. Of the 147 patients, 85 were boys and 62 were girls. The most frequent trauma occurred in the age of 11 years. The maxillary central incisors were found to be the most affected tooth in both primary and permanent dentition injuries. The maxillary arch is involved in a higher percentage of trauma cases (95.72%). The most common cause of injuries are falls (67.34%). In the primary dentition, the most common type of injury is extrusive luxation (38.23%) and in the permanent dentition, it is fracture of enamel,dentin without pulpal involvement (50.5%). From 147 patients, only 82 presented to our clinic within 1 h and 10 days after the injury time. It reveals that there is a need to inform the public of what they should do in cases of dental trauma, and how important it is to contact a dentist immediately. [source]


    Enlarged vestibular aqueduct in two male siblings

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2002
    C M Varghese MSc MRCP FRCPCH
    This report describes the case history of two male siblings with sensorineural hearing loss and an enlarged vestibular aqueduct (EVA). Sibling 1 presented with a history of intermittent self-limiting ataxia and hearing loss at the age of 25 months and sibling 2 presented with a similar history at the age of 18 months. MRI showed an enlarged endolymphatic duct and sac bilaterally in both children. Perchlorate discharge tests were positive in both infants leading to a diagnosis of Pendred syndrome. A number of conditions associated with EVA are discussed with a view to devising management strategies. [source]


    The hippocampus and caudomedial neostriatum show selective responsiveness to conspecific song in the female zebra finch

    DEVELOPMENTAL NEUROBIOLOGY, Issue 1 2002
    David J. Bailey
    Abstract The perception of song is vital to the reproductive success of both male and female songbirds. Several neural structures underlying this perception have been identified by examining expression of immediate early genes (IEGs) following the presentation of conspecific or heterospecific song. In the few avian species investigated, areas outside of the circuit for song production contain neurons that are active following song presentation, specifically the caudal hyperstriatum ventrale (cHV) and caudomedial neostriatum (NCM). While studied in detail in the male zebra finch, IEG responses in these neural substrates involved in song perception have not been quantified in females. Therefore, adult female zebra finches were presented with zebra finch song, nonzebra finch song, randomly generated tones, or silence for 30 min. One hour later they were sacrificed, and their brains removed, sectioned, and immunocytochemically processed for FOS expression. Animals exposed to zebra finch song had a significantly higher density of FOS-immunoreactive cells in the NCM than those presented with other songs, tones, or silence. Neuronal activation in the cHV was equivalent in birds that heard zebra finch and non-zebra finch song, expression that was higher than that observed in the groups that heard no song. Interestingly, the hippocampus (HP) and adjacent parahippocampal area (AHP) were activated in a manner comparable to the NCM. These results suggest a general role for the cHV in song perception and a more specific role for the NCM and HP/AHP in facilitating recognition of and responsiveness to species-specific song in female zebra finches. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 43,51, 2002 [source]


    Epiphrenic diverticula: minimal invasive approach and repair in five patients

    DISEASES OF THE ESOPHAGUS, Issue 1 2001
    D. L. Van Der Peet
    Epiphrenic esophageal diverticula are rare and often asymptomatic. If surgery is mandatory, a thoracotomy is used to resect the diverticulum. The results of a minimal invasive approach and repair in five patients are presented. These patients, who all presented with an epiphrenic diverticulum, were evaluated using barium swallow study, esophagoscopy, and manometry. The diverticula were approached by thoracoscopy in all patients and a description of the surgical technique is given. The diverticula were resected using a right-sided approach in four patients. One patient with a diverticulum in the distal esophagus required conversion to laparoscopy. A myotomy was performed in two patients because of high pressures in the lower esophageal sphincter. The postoperative course was uncomplicated in four patients. One patient with Ehlers,Danlos disease had a complicated course owing to leakage, resulting in two re-operations by means of thoracotomy. There was no mortality. The minimal invasive approach of epiphrenic diverticula is feasible. The long-term results are awaited. [source]


    An evaluation of a visual biofeedback intervention in dyslexic adults

    DYSLEXIA, Issue 1 2005
    Elizabeth Liddle
    Abstract A prototype of a biofeedback system designed to treat dyslexia by improving heart-rate variability was evaluated in a single blind study of dyslexic adults. Treatment consisted of four 15 minute exposures to a visual display synchronized with either the participant's own cardiac cycle (intervention condition), or of a synthesized cardiac cycle (placebo condition). Repeated measures were made of picture naming speed, single word reading speed and accuracy, copying speed, heart-rate variability and performance on a lateralized visual temporal order judgement task. Small but significant improvements were found in reading and naming speed in the treatment group relative to the placebo group. No significant improvements were found in unspeeded reading measures. Results from heart-rate measures indicated that treatment had effected a shift in the ratio between parameters reflecting the influence of the sympathetic and parasympathetic autonomic nervous systems (ANS), respectively, in favour of the parasympathetic. In the temporal order judgement task, participants who received treatment showed a reduced level of overall improvement relative to that seen in those who received placebo, coupled with evidence of a shift in visual attention from left to right hemifield in their pattern of performance. The results are interpreted as indicating that the treatment induces a shift in autonomic balance in favour of the parasympathetic ANS, and that this shift is also reflected in increased efficiency of left cerebral hemisphere circuits implicated in the perceptual-motor processes required for naming and reading fluency. Conversely, it is also reflected in lower spatial awareness of peripheral visual stimuli, particularly those presented to left hemifield. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Defining Economics: The Long Road to Acceptance of the Robbins Definition

    ECONOMICA, Issue 2009
    ROGER E. BACKHOUSE
    Robbins' Essay gave economics a definition that came to dominate the professional literature. This definition laid a foundation that could be seen as justifying both the narrowing of economic theory to the theory of constrained maximization or rational choice and economists' ventures into other social science fields. Though often presented as self-evidently correct, both the definition itself and the developments that it has been used to support were keenly contested. This paper traces the reception, diffusion and contesting of the Robbins definition, arguing that this process took around three decades and that even then there was still significant dissent. [source]


    De novo epileptic confusion in the elderly: A 1-year prospective study

    EPILEPSIA, Issue 6 2010
    Olivier Veran
    Summary Purpose:, Nonconvulsive status epilepticus (NCSE) is clinically difficult to diagnose, especially in old patients without epilepsy, and requires electroencephalography (EEG) for diagnosis. Its incidence among elderly patients with confusion of unknown origin (CUO) remains undetermined. Methods:, A 1-year prospective study was conducted in patients aged 60 years or older, for whom EEG was requested because of confusion considered to be of unknown origin after initial clinical, biologic, and imaging investigations. Diagnosis criteria included a validated clinical assessment scale to confirm confusion. Results:, Of 44 patients with confirmed CUO, 7 presented with de novo NCSE. NCSE population had a mean age of 76 years (range, 60,97 years). No statistically significant differences were found between NCSE patients and others for age, drugs, presence of myoclonia, eyelid myoclonia, tachycardia, or agitation. In contrast, an acute onset (<24 h), gender (100% female among NCSE patients), and lack of clinical response to simple commands were significantly associated with NCSE. No differences between the two groups were evidenced for mortality and morbidity (length of hospitalization, social outcome, and so on). Discussion:, Almost 16% of patients aged 60 or older with confusion of unknown origin had NCSE, according to this first prospective study. Female patients with rapid onset (<24 h) of symptoms and lack of response to simple commands were at a higher risk of presenting with NCSE. [source]


    The classic lacunar syndromes: clinical and neuroimaging correlates

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2008
    J. De Reuck
    Background:, Although lacunar syndromes (LSs) are aimed to be linked to lacunar infarcts, the relation between both is still not very well defined. Purpose:, The present retrospective study tries to define more specifically the clinical and the neuroimaging characteristics of the five most classic LSs. Patients and methods:, Out of a series of 1617 consecutive stroke patients, admitted to the Ghent University Hospital, 293 presented a classic LS. Magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was performed within 5 days after stroke onset in 227 patients. An acute territorial infarct was demonstrated in 54 patients. The study population finally consisted of 173 patients with a classic LS in whom the responsible lacune was demonstrated or in the absence of another type of infarct. Results:, The responsible lacune was demonstrated with DWI in 104 patients. Pure motor stroke (MS) correlated significantly with the presence of the responsible lacune in the internal capsule (P = 0.000147) and with the stroke severity (P = 0.00724). No significant correlation was observed between the location of the lacunes and the other LS's. Conclusion:, Pure MS has to be considered as the most specific lacunar syndrome. [source]


    Molecular cytogenetic characterization of proximal-type epithelioid sarcoma

    GENES, CHROMOSOMES AND CANCER, Issue 3 2004
    Elena Lualdi
    Proximal-type epithelioid sarcoma is a recently described soft-tissue tumor that is distinguished from conventional-type epithelioid sarcoma by a far more aggressive clinical course, frequent location in the proximal anatomic regions, and variable rhabdoid morphology. Because of their rarity and peculiar morphology, proximal-type epithelioid sarcomas frequently pose serious diagnostic dilemmas, being easily misdiagnosed as a variety of other malignant neoplasms. To date, the information available on the genetic alterations associated with this tumor entity has been confined to single conventional cytogenetic reports. In this article, we present the results of a conventional and molecular cytogenetic analysis of six proximal-type epithelioid sarcomas. Spectral karyotyping analysis of these cases deciphered the characteristics of several marker chromosomes and complex translocations, leading to the recognition of recurrent rearrangements. The most frequently involved chromosome arm was 22q, and the identification of two cases with a similar translocation, t(10;22), suggests a role for one or more genes on chromosome 22 in the pathogenesis of this tumor and provides an opportunity for finely mapping the translocation-associated breakpoints. Chromosome arm 8q gain was also a frequent event and correlated with gain of MYC gene copy number, as demonstrated by fluorescence in situ hybridization. A review of both cases reported in the literature and those presented in this study reinforced the involvement of chromosomes 8 and 22 and also indicated frequent rearrangements of chromosomes 7, 14, 18, and 20. © 2004 Wiley-Liss, Inc. [source]


    Carbon and oxygen isotopes: a tool for Jurassic and early Cretaceous pelagic correlation (southern Spain)

    GEOLOGICAL JOURNAL, Issue 4 2002
    J. Rey
    Abstract The isotopic evolution of ,13C and ,18O is reported for the Jurassic and early Cretaceous in two pelagic sections of the External Zones in the Betic Cordilleras (SE Spain). Stable isotope curves from pelagic trough and swell sections display similar patterns. Variations in ,18O and ,13C values from strata at equivalent age probably reflect both early diagenetic cementation and later temperature-related burial diagenesis. Comparison of global isotope curves with those presented in this work allows the differentiation of global from local events. Thus, the anoxic event during the early Toarcian (falciferum Zone) is characterized by elevated ,13C and depressed ,18O values. The isotopic record also allows the detection of the middle Oxfordian transgression. There are other peaks for the late Toarcian, early Bajocian, Callovian and early Berriasian that can also be used as tools for correlation purposes. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Improved microseismic event location by inclusion of a priori dip particle motion: a case study from Ekofisk

    GEOPHYSICAL PROSPECTING, Issue 5 2010
    G.A. Jones
    ABSTRACT Microseismic monitoring in petroleum settings provides insights into induced and naturally occurring stress changes. Such data are commonly acquired using an array of sensors in a borehole, providing measures of arrival times and polarizations. Events are located using 1D velocity models, P- and S-wave arrival times and the azimuths of P-wave particle motions. However in the case of all the sensors being deployed in a vertical or near-vertical borehole, such analysis leads to an inherent 180° ambiguity in the source location. Here we present a location procedure that removes this ambiguity by using the dip of the particle motion as an a priori information to constrain the initial source location. The new procedure is demonstrated with a dataset acquired during hydraulic fracture stimulation, where we know which side of the monitoring well the events are located. Using a 5 -step location procedure, we then reinvestigate a microseismic data set acquired in April 1997 at the Ekofisk oilfield in the North Sea. Traveltimes for 2683 candidate events are manually picked. A noise-weighted analytic-signal polarization analysis is used to estimate the dip and azimuth of P-wave particle motions. A modified t-test is used to statistically assess the reliability of event location. As a result, 1462 events are located but 627 are deemed to be statistically reliable. The application of a hierarchal cluster analysis highlights coherent structures that cluster around wells and inferred faults. Most events cluster at a depth of roughly 3km in the Ekofisk chalk formation but very little seismicity is observed from the underlying Tor chalk formation, which is separated from the Ekofisk formation by an impermeable layer. We see no evidence for seismicity in the overburden but such events may be too distant to detect. The resulting picture of microseismicity at Ekofisk is very different from those presented in previous studies. [source]


    Disseminated infection due to Encephalitozoon cuniculi in a patient with AIDS: case report and review

    HIV MEDICINE, Issue 3 2000
    S Fournier
    Objective and methods Infections due to microsporidia are increasingly recognized as opportunistic infections in patients with AIDS. We describe here a case of disseminated infection due to Encephalitozoon cuniculi and review the literature on this microsporidial infection. Results All 12 patients reported in the literature had AIDS and nine presented with disseminated infection involving the kidneys, sinuses, lungs, brain and conjunctiva. Asymptomatic infection was seen in three patients. Microsporidia were detected by light microscopy examination of urine samples in all the cases. Species identification was performed by various genotypic methods or transmission electron microscopy. Eight of 12 patients who received albendazole therapy experienced clinical improvement with documented clearance of spores in five of these eight patients. Two patients relapsed. Conclusions E. cuniculi infection should be considered in severely immunocompromised HIV-infected patients with multi-organ involvement and fever, especially when renal failure is present. Microsporidial spores are usually seen in urine samples and in the involved organ. Albendazole therapy seems to be effective. [source]


    Resection of renal metastases to the pancreas: a surgical challenge

    HPB, Issue 3 2003
    D Zacharoulis
    Background Metastasis to the pancreas from renal cell carcinoma (RCC) is distinctly uncommon. Most cases are detected at an advanced stage of the disease and are thus unsuitable for resection. A solitary RCC metastasis to the head of pancreas is rarely encountered and, although it is potentially amenable to surgical resection, surgeons may be hesitant to perform pancreatoduodenectomy. Cases outlines Two patients with a solitary RCC metastasis to the head of pancreas were treated by pancreatoduodenectomy, while a third with multiple RCC metastases declined any treatment. Two of the patients were asymptomatic, and one presented with anaemia and mild abdominal pain. Computed tomography (CT) and angiography were used to exclude other metastases and to assess resectability of the pancreatic tumour. All three patients are still alive, those with resectable disease at 2 years and 9 years and the one with irresectable disease at 4 years. Discussion Isolated RCC metastasis to the pancreas is a rare event. Patients present either on follow-up imaging or with symptoms such as mild abdominal pain, weight loss, jaundice, anaemia or gastrointestinal bleeding (whether occult or overt). Dynamic spiral CT can visualise the tumour and exclude distant metastasis. Angiography often reveals a highly vascularised tumour and will help to assess resectability. In the absence of widespread disease, pancreatic resection can provide long-term survival in metastatic RCC, although few cases have been reported with lengthy follow-up. The prognosis is better than for pancreatic adenocarcinoma. [source]


    A mixture of seven antiandrogens induces reproductive malformations in rats

    INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2008
    Cynthia V. Rider
    Summary To date, regulatory agencies have not considered conducting cumulative risk assessments for mixtures of chemicals with diverse mechanisms of toxicity because it is assumed that the chemicals will act independently and the individual chemical doses are not additive. However, this assumption is not supported by new research addressing the joint effects of chemicals that disrupt reproductive tract development in the male rat by disrupting the androgen signalling pathway via diverse mechanisms of toxicity [i.e. androgen receptor (AR) antagonism in the reproductive tract vs. inhibition of androgen synthesis in the foetal testis]. In this study, pregnant rats were exposed to four dilutions of a mixture containing vinclozolin, procymidone, linuron, prochloraz, benzyl butyl phthalate, dibutyl phthalate and diethylhexyl phthalate during the period of sexual differentiation and male offspring were assessed for effects on hormone sensitive endpoints including: anogenital distance, infant areolae retention and reproductive tract tissue weights and malformations. The ratio of the chemicals in the mixture was based upon each chemical's ED50 for inducing reproductive tract malformations (hypospadias or epididymal agenesis). The observed responses from the mixture were compared with predicted responses generated with a toxic equivalency approach and models of dose addition, response addition or integrated addition. As hypothesized, we found that the mixture of chemicals that alter the androgen signalling pathway via diverse mechanisms disrupted male rat reproductive tract differentiation and induced malformations in a cumulative, dose-additive manner. The toxic equivalency and dose addition models provided the best fit to observed responses even though the chemicals do not act via a common cellular mechanism of action. The current regulatory framework for conducting cumulative risk assessments needs to consider the results, including those presented herein, which indicate that chemicals that disrupt foetal tissues during sexual differentiation act in a cumulative, dose-additive manner irrespective of the specific cellular mechanism of toxicity. [source]


    Molecular cloning of several rat ABC transporters including a new ABC transporter, Abcb8, and their expression in rat testis

    INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2006
    Nathalie Melaine
    Summary Several members of the ABC transporter superfamily play an important role in testicular physiology and defence against anticancer drugs. Using a reverse transcription-polymerase chain reaction strategy with degenerate primers and rat testis RNA as template, we have looked for the presence of other members of this superfamily. Of the six partial cDNA found, five corresponded to ABC transporters already known ,Mdr1b, Mrp1, Tapl/Abcb9, Umat/Abcb6 and Sur2/Abcc9, and one presented a strong homology with mouse and human ABCB8. Using a 5, and 3, RACE approach, we cloned the full-length cDNA and found that the predicted protein presented 92% and 80% homology with the mouse and human proteins respectively. Strong expression of rat abcb8 was found in heart, brain and testis when compared with liver, lung and spleen. In the testis, rat abcb8 was expressed both in the somatic Sertoli cells and peritubular cells and in the germline (spermatogonia and pachytene spermatocytes). Furthermore, Umat/Abcb6 was very highly expressed in the testis (high amounts in meiotic pachytene spermatocytes and low amount in post-meiotic early spermatids). In conclusion, we confirm the presence of several ABC transporters in the testis and also provide evidence of the presence of Abcb8 in the organ. [source]


    H-doped PbTiO3: Structure and electronic properties

    INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2007
    Arvids Stashans
    Abstract The geometry and electronic properties of the interstitial H atom in the tetragonal PbTiO3 crystal have been studied using an advanced quantum chemical computer code developed for the modeling of crystals. The inserted H atom was found to bind to one of the O atoms and to form the hydroxyl, OH group, with the inter-atomic distance equal to 0.93 Å and 1.00 Å for the hydroxyls containing O atom in the dimerized and nondimerized TiOTi chains, respectively. Atomic displacements in the vicinity of OH complex are calculated and analyzed in relation to the H-produced changes upon the atomic charges in defective region. The role of H impurity on the ferroelectric polarization in the tetragonal PbTiO3 is discussed in terms of the results obtained in our research and those presented in the other studies on this subject. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [source]


    Read|Write: Table + Chair

    JOURNAL OF ARCHITECTURAL EDUCATION, Issue 2 2004
    STEPHEN TURK
    The Table + Chair project forms part of a series of closely related architectural interventions that also included the production of a new entry façade for the School of Architecture reception offices at Ohio State University. The work entailed the production of a table and chair that were to be used by students in the process of fillingout official paperwork while waitingto meet with school administrators and counselors. These paper "forms" would become the written code of the students' education,their program,and in many ways would determine the course of their education. This presented an opportunity to fabricate furniture that explored the effects of the cross-contamination of material presence with informational patterns by using digital technologies. [source]


    Aerobic biological treatment of waste- waters containing dichloromethane

    JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2007
    Sandra C Moura
    Abstract BACKGROUND: Volatilization has been advanced as one of the predominant phenomena contributing to volatile organic carbon emissions from wastewater treatment plants (WWTPs). In this study, strategies for minimizing such air stripping losses when treating a liquid stream containing dichloromethane (DCM), aiming at decreasing the overall emission inventory from WWTPs, were investigated. RESULTS: System R1, consisting of a continuous flow stirred tank reactor (CSTR) treating a liquid stream containing DCM at a concentration of 12 mmol dm,3 presented a biodegradation efficiency (BE) of 68%, based upon chloride release, with 10% of measurable losses, mainly due to volatilization, and 22% of unmeasurable losses. System R2 introduced operational designs aiming at decreasing DCM volatilization. In Experiment R2.1, a biotrickling filter, through which the air stripped from the CSTR was driven, was introduced leading to a reduction from 10% to 7% on the measurable losses. In Experiment R2.2, the air stripped from the CSTR was recirculated at a flow rate of 2.4 dm3 h,1 through the reactor medium before entering the biotrickling filter. The BE was improved from 69% to 82% and the losses associated with air stripping were successfully reduced to 2%. The proposed design, including air recirculation and the biotrickling filter, increased the ratio between the biodegradation rate and the volatilization rate from 7 to 41. CONCLUSIONS: Recirculation of the gaseous effluent through the reactor medium, which allowed for higher residence time within the bioreactor, was shown to be a successful strategy for improving the treatment process, thus minimizing DCM volatilization losses. Copyright © 2007 Society of Chemical Industry [source]


    Correlation optimized warping and dynamic time warping as preprocessing methods for chromatographic data

    JOURNAL OF CHEMOMETRICS, Issue 5 2004
    Giorgio Tomasi
    Abstract Two different algorithms for time-alignment as a preprocessing step in linear factor models are studied. Correlation optimized warping and dynamic time warping are both presented in the literature as methods that can eliminate shift-related artifacts from measurements by correcting a sample vector towards a reference. In this study both the theoretical properties and the practical implications of using signal warping as preprocessing for chromatographic data are investigated. The connection between the two algorithms is also discussed. The findings are illustrated by means of a case study of principal component analysis on a real data set, including manifest retention time artifacts, of extracts from coffee samples stored under different packaging conditions for varying storage times. We concluded that for the data presented here dynamic time warping with rigid slope constraints and correlation optimized warping are superior to unconstrained dynamic time warping; both considerably simplify interpretation of the factor model results. Unconstrained dynamic time warping was found to be too flexible for this chromatographic data set, resulting in an overcompensation of the observed shifts and suggesting the unsuitability of this preprocessing method for this type of signals. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Thrombotic thrombocytopenic purpura: 24 years of experience at the American University of Beirut Medical Center

    JOURNAL OF CLINICAL APHERESIS, Issue 3 2004
    Ali Shamseddine
    Abstract Thrombotic thrombocytopenic purpura (TTP) is a hematological syndrome defined by the presence of thrombocytopenia and microangiopathic hemolytic anemia without a clinically apparent etiology. Patients may also suffer from fever in addition to neurological and renal impairment. Treatment should be initiated as soon as possible, otherwise this rare disease can be fatal. The main treatment options include therapeutic plasma exchange, fresh frozen plasma infusion, and adjuvant agents such as steroids and antiplatelet drugs. A search of patient records was carried out at the American University of Beirut Medical Center looking for patients who developed TTP over a 24-year period extending from 1980 to 2003. Relevant information was collected and analyzed. A total of 47 records were found. All presented with anemia and thrombocytopenia, 83% had neurological symptoms, 61.7% had fever and 34% had renal impairment. All patients were treated with a multimodality regimen including therapeutic plasma exchange, FFP infusion, steroids, antiplatelet agents, vincristine and others. 38 (81%) cases achieved complete remission. Out of these, 12 (31.6%) relapsed and responded to treatment. Patients who did not receive plasma exchange were more likely to relapse (P = 0.032). A second relapse was observed in 6 cases. The overall mortality rate from TTP over 24 years was 21.3%. TTP remains a fatal disease. A high index of suspicion should, therefore, always be present. Treatment options should be further developed and patients should directly be referred to tertiary care centers. J. Clin. Apheresis 19:119,124, 2004. © 2004 Wiley-Liss, Inc. [source]


    Mucinous hidradenoma: a report of three cases

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2007
    Seng Geok Nicholas Goh
    Mucinous cutaneous adnexal tumors are an uncommon occurrence. We describe three cases of mucinous hidradenoma characterized by diffuse and prominent mucinous cell proliferation and discuss the relevant literature. The patients (two men and one woman) ranged in age from 32 to 72 years. The lesions were completely excised, and all patients were alive without evidence of disease (follow-up interval 3,4 years). Case 1 presented as a 1.3-cm eyelid nodule and histology showed a mucinous apocrine hidradenoma with a proliferation of mucinous cells and apocrine glands. Case 2, from the shoulder of a 40-year-old man, was a 2.5-cm well-circumscribed nodule composed of hyperplastic villoglandular proliferation of mucinous cells with focal squamous whorls and focal columnar glandular cells showing decapitation secretion. The tumor was also interpretated as a mucinous hidradenoma, most likely of follicular-apocrine origin. Case 3 was a 3.0-cm scalp nodule. The histology showed a mucinous clear-cell hidradenoma composed of numerous mucinous glands amidst small squamous cells with clear cytoplasm and a hyalinized fibrovascular stroma. [source]


    Clinical application of wireless capsule endoscopy

    JOURNAL OF DIGESTIVE DISEASES, Issue 2 2003
    Zhi Zheng GE
    BACKGROUND: Diagnostic modalities for identifying lesions within the small bowel have been quite limited. Wireless capsule endoscopy (WCE) is a new, innovative technique that can detect very small mucosal lesions in the entire small bowel and can be used in the outpatient setting. The present study explored the diagnostic value, tolerance and safety of WCE in the identification of small bowel pathology that was not detected with conventional small bowel imaging studies. METHODS: From May through September 2002, 15 patients with suspected small bowel diseases were prospectively examined, Of them, 12 presented with persistent obscure gastrointestinal bleeding and negative findings on upper endoscopy, colonoscopy, small bowel radiography, and bleeding-scan scintig-raphy or mesenteric angiography. RESULTS: Wireless capsule endoscopy identified pathologic small bowel findings in 11 of the 15 patients (73%): angioectasias, Dieulafoy's lesion, polypoid lesion, submucosal mass, Crohn's disease, carcinoid tumor, lipoma, aphthous ulcer, and hemorrhagic gastritis; four of the patients had two lesions. The images displayed were considered to be good. The capsule endoscopes remained in the stomach for an average of 82 min (range 6,311 min) and the mean transit time in the small bowel was 248 min (range 104,396 min). The mean time of recording was 7 h 29 min (from 5 h to 8 h 30 min). The mean time to reach the cecum was 336 min (180,470 min). The average number of the images transmitted by the capsule was 57 919 and the average time the physician took to review the images transmitted by the capsule was 82 min (range 30,120 min). The average time of elimination of the capsule was 33 h (range 24,48 h). All 15 patients reported that the capsule was easy to swallow, painless, and preferable to conventional endoscopy. No complications were observed. CONCLUSIONS: Wireless capsule endoscopy is safe, well tolerated, and useful for identifying occult lesions of the small bowel, especially in patients who present with obscure gastrointestinal bleeding. [source]


    Association of cytokine genetic polymorphisms with the humoral immune response to recombinant vaccine against HBV in infants

    JOURNAL OF MEDICAL VIROLOGY, Issue 6 2010
    Luciana Conci Macedo
    Abstract The prevention of hepatitis B by vaccination is one the most efficient tools to avoid the transmission of the virus, although a considerable variability to the anti-HBsAg antibody response has been described. Recently, polymorphisms of cytokine regulating genes have been described which seem to influence the immune response to various antigens. This article's objective was to evaluate the influence of cytokine genetic polymorphisms onto the humoral immune response to hepatitis B vaccine in infants. Vaccinated children were classified according to the level of anti-HBsAg antibody titles. The genotyping for TNF (,308), TGFB1 (+869, +915), IL-10 (,1082, ,819, ,592), IL-6 (,174), and IFNG (+874) was accomplished by the PCR-SSP technique. The TNF (,308) allele A presented a lower but not statistically significant frequency at 5% level in high responder patients (3.7% vs. 12.3%, P,=,0.0919). The same was seen for the TNF (,308) genotype GA (7.4% vs. 24.5%, P,=,0.0757). Further studies in other populations and evaluation of a greater number of individuals may contribute for a better understanding of the cytokine gene polymorphism influence in general and TNF polymorphism more specifically in the humoral immune response to the HBsAg vaccination in newborn children. J. Med. Virol. 82:929,933, 2010. © 2010 Wiley-Liss, Inc. [source]


    Prediction of human pharmacokinetics,gut-wall metabolism

    JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2007
    Urban Fagerholm
    Intestinal mucosal cells operate with different metabolic and transport activity, and not all of them are involved in drug absorption and metabolism. The fraction of these cells involved is dependent on the absorption characteristics of compounds and is difficult to predict (it is probably small). The cells also appear comparably impermeable. This shows a limited applicability of microsome intrinsic clearance (CLint)-data for prediction of gut-wall metabolism, and the difficulty to predict the gut-wall CL (CLGW) and extraction ratio (EGW). The objectives of this review were to evaluate determinants and methods for prediction of first-pass and systemic EGW and CLGW in man, and if required and possible, develop new simple prediction methodology. Animal gut-wall metabolism data do not appear reliable for scaling to man. In general, the systemic CLGW is low compared with the hepatic CL. For a moderately extracted CYP3A4-substrate with high permeability, midazolam, the gut-wall/hepatic CL-ratio is only 1/35. This suggests (as a general rule) that systemic CLGW can be neglected when predicting the total CL. First-pass EGW could be of importance, especially for substrates of CYP3A4 and conjugating enzymes. For several reasons, including those presented above and that blood flow based models are not applicable in the absorptive direction, it seems poorly predicted with available methodology. Prediction errors are large (several-fold on average; maximum-15-fold). A new simple first-pass EGW -prediction method that compensates for regional and local differences in absorption and metabolic activity has been developed. It has been based on human cell in-vitro CLint and fractional absorption from the small intestine for reference (including verapamil) and test substances, and in-vivo first-pass EGW -data for reference substances. First-pass EGW -values for CYP3A4-substrates with various degrees of gastrointestinal uptake and CLint and a CYP2D6-substrate were well-predicted (negligible errors). More high quality in-vitro CLint - and in-vivo EGW -data are required for further validation of the method. [source]


    Propylene polymerization with nickel,diimine complexes containing pseudohalides

    JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2006
    Marcos L. Dias
    Abstract DADNiX2 nickel,diimine complexes [DAD = 2,6- iPr2C6H3NC(Me)C(Me)N2,6- iPr2C6H3] containing nonchelating pseudohalide ligands [X = isothiocyanate (NCS) for complex 1 and isoselenocyanate (NCSe) for complex 2] were synthesized, and the propylene polymerization with these complexes and also with the Br ligand (X = Br for complex 3) activated by methylaluminoxane (MAO) were investigated (systems 1, 2, and 3/MAO). The polypropylenes obtained with systems 1, 2, and 3 were amorphous polymers and had high molecular weights and narrow molecular weight distributions. Catalyst system 1 showed a relatively high activity even at a low Al/Ni ratio and reached the maximum activity at the molar ratio of Al/Ni = 500, unlike system 3. Increases in the reaction temperature and propylene pressure favored an increase in the catalytic activity. The spectra of polypropylenes looked like those of propylene,ethylene copolymers containing syndiotactic propylene and ethylene sequences. At the same temperature and pressure, system 2 presented the highest number of propylene sequences, and system 3 presented the lowest. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 458,466, 2006 [source]


    Mechanical Behavior and Failure Analysis of Prosthetic Retaining Screws after Long-term Use In Vivo.

    JOURNAL OF PROSTHODONTICS, Issue 3 2008
    Part 1: Characterization of Adhesive Wear, Structure of Retaining Screws
    Abstract Purpose: The general aim of this study and those presented in Parts 2,4 of this series was to characterize the structure, properties, wear, and fracture of prosthetic retaining screws in fixed detachable hybrid prostheses after long-term use in vivo. This part of the overall investigation addresses whether there are differences in thread wear between the screws closest to the fulcrum and those that are farthest from the fulcrum in fixed detachable hybrid prostheses. Materials and Methods: The total number of prosthetic retaining screws used in this study was 100 (10 new and 90 used). New screws (controls) from Nobel Biocare (NB) were divided into Group 1 (slotted) and Group 2 (hexed). Ninety used screws (in service 18,120 months) were retrieved from fixed detachable hybrid prostheses in 18 patients (5 screws from each patient, 60 from NB and 30 from Sterngold). The used screws were divided into 18 groups. Additionally, each group was subdivided into A and B categories. Category A contained the middle three prosthetic screws, which were considered the farthest screws from the fulcrum line. Category B contained the most posterior two screws, which were considered the screws closest to the fulcrum line. All 100 screws were subjected to thorough, nondestructive testing. Results: Light and scanning electron microscopic examination of all used screws for each group revealed surface deterioration of the active profile of the screw threads consistent with adhesive wear. The observed thread profile deterioration ranged from mild to severe. The wear was aggressive enough to cause galling, which led to thinning of the threads and, in severe cases, to knife-edges at thread crests. In ten groups, the most anterior three screws exhibited more wear than the most posterior two screws. In addition to thread wear, severe plastic deformation was detected on the bottom part of each screw for three groups, and a long external longitudinal crack was detected in one screw of Group 2. Conclusions: The findings of this study and those presented in Parts 2,4 demonstrate that different retaining screws from the same manufacturer and/or from different manufacturers have different geometrical design, microstructures, major alloy constituents, and microhardness, and that these differences influence their preload and fractured load values. In this part of the overall investigation, the occurrence of galling as a result of wear involving prosthetic retaining screws appears to be an inevitable and unavoidable consequence of long-term use in vivo in fixed detachable hybrid prostheses regardless of the intended/original preload value. The galling rate is greater on the middle three screws compared to the most posterior two screws in fixed detachable hybrid prostheses. The wear pattern is consistent with an adhesive wear mechanism; however, this study does not provide enough data to support a definitive analysis. [source]


    Denaturing capillary electrophoresis for automated detection of L858R mutation in exon 21 of the epidermal growth factor receptor gene in prediction of the outcome of lung cancer therapy

    JOURNAL OF SEPARATION SCIENCE, JSS, Issue 15 2010
    Lucie Benesova
    Abstract The presence of activating mutations within the tyrosine kinase domain of the epidermal growth factor receptor gene has been attributed to a positive response to biological therapy of lung cancer by small-molecular tyrosine kinase inhibitors, gefitinib and erlotinib. Among the two most significant mutation types are deletions in exon 19 and a single point substitution in exon 21 (termed L858R). The exon 19 deletions can readily be examined by fragment analysis, due to the characteristic length difference between the normal and mutated PCR product. Analysis of the L858R point mutation, however, presents a greater challenge. The current paper is aimed at developing a sensitive, yet simple, low-cost mutation detection assay directed at the L858R mutation using a method based on CE of heteroduplexes under partial denaturing conditions. We perform optimization of separation conditions on different commercial instruments including ones equipped with 8, 16 and 96 capillaries. We present normalized migration reproducibility in the range from 1 (8 and 16) to 5% (96) RSD. A reliable distinction of the R836R silent polymorphism from a potential presence of the L858R mutation is also demonstrated. In its implementation, the presented assay is just another application running on a conventional CE platform without the need of dedicated instrumentation. [source]


    Pulsed radio-frequency electromagnetic fields: dose-dependent effects on sleep, the sleep EEG and cognitive performance

    JOURNAL OF SLEEP RESEARCH, Issue 3 2007
    SABINE J. REGEL
    Summary To establish a dose,response relationship between the strength of electromagnetic fields (EMF) and previously reported effects on the brain, we investigated the influence of EMF exposure by varying the signal intensity in three experimental sessions. The head of 15 healthy male subjects was unilaterally exposed for 30 min prior to sleep to a pulse-modulated EMF (GSM handset like signal) with a 10 g-averaged peak spatial specific absorption rate of (1) 0.2 W kg,1, (2) 5 W kg,1, or (3) sham exposed in a double-blind, crossover design. During exposure, subjects performed two series of three computerized cognitive tasks, each presented in a fixed order [simple reaction time task, two-choice reaction time task (CRT), 1-, 2-, 3-back task]. Immediately after exposure, night-time sleep was polysomnographically recorded for 8 h. Sleep architecture was not affected by EMF exposure. Analysis of the sleep electroencephalogram (EEG) revealed a dose-dependent increase of power in the spindle frequency range in non-REM sleep. Reaction speed decelerated with increasing field intensity in the 1-back task, while accuracy in the CRT and N-back task were not affected in a dose-dependent manner. In summary, this study reveals first indications of a dose,response relationship between EMF field intensity and its effects on brain physiology as demonstrated by changes in the sleep EEG and in cognitive performance. [source]