New mechanism of oral immunity to mucosal candidiasis in hyper-IgE syndrome.

Science.gov (United States)

Conti, H R; Baker, O; Freeman, A F; Jang, W S; Holland, S M; Li, R A; Edgerton, M; Gaffen, S L

2011-07-01

Oropharyngeal candidiasis (OPC, thrush) is an opportunistic infection caused by the commensal fungus Candida albicans. An understanding of immunity to Candida has recently begun to unfold with the identification of fungal pattern-recognition receptors such as C-type lectin receptors, which trigger protective T-helper (Th)17 responses in the mucosa. Hyper-IgE syndrome (HIES/Job's syndrome) is a rare congenital immunodeficiency characterized by dominant-negative mutations in signal transducer and activator of transcription 3, which is downstream of the Th17-inductive cytokines interleukin (IL)-6 and IL-23, and hence patients with HIES exhibit dramatic Th17 deficits. HIES patients develop oral and mucocutaneous candidiasis, supporting a protective role for Th17 cells in immunity to OPC. However, the Th17-dependent mechanisms of antifungal immunity in OPC are still poorly defined. An often unappreciated aspect of oral immunity is saliva, which is rich in antimicrobial proteins (AMPs) and exerts direct antifungal activity. In this study, we show that HIES patients show significant impairment in salivary AMPs, including β-defensin 2 and Histatins. This tightly correlates with reduced candidacidal activity of saliva and concomitantly elevated colonization with Candida. Moreover, IL-17 induces histatins in cultured salivary gland cells. This is the first demonstration that HIES is associated with defective salivary activity, and provides a mechanism for the severe susceptibility of these patients to OPC.

Females use self-referent cues to avoid mating with previous mates

OpenAIRE

Ivy, Tracie M; Weddle, Carie B; Sakaluk, Scott K

2005-01-01

Females of many species mate repeatedly throughout their lives, often with many different males (polyandry). Females can secure genetic benefits by maximizing their diversity of mating partners, and might be expected, therefore, to forego matings with previous partners in favour of novel males. Indeed, a female preference for novel mating partners has been shown in several taxa, but the mechanism by which females distinguish between novel males and previous mates remains unknown. We show that...

Plasticity and diversity of tRNA anticodon determinants of substrate recognition by eukaryotic A37 isopentenyltransferases

OpenAIRE

Lamichhane, Tek N.; Blewett, Nathan H.; Maraia, Richard J.

2011-01-01

Transfer RNAs are subject to a wide variety of modifications. Once such modification is N6-(isopentenyl)adenosine. This paper examines the substrate specificity of modifying enzymes from budding and fission yeast. Complex patterns of substrate determinants are uncovered. These determinants differ between the budding and fission yeast in enzymes. This study demonstrates previously unappreciated molecular plasticity and biological diversity of the tRNA-isopentenyltransferase system in eukaryotes.

Mechanical and histological characterization of the abdominal muscle. A previous step to modelling hernia surgery.

Science.gov (United States)

Hernández, B; Peña, E; Pascual, G; Rodríguez, M; Calvo, B; Doblaré, M; Bellón, J M

2011-04-01

The aims of this study are to experimentally characterize the passive elastic behaviour of the rabbit abdominal wall and to develop a mechanical constitutive law which accurately reproduces the obtained experimental results. For this purpose, tissue samples from New Zealand White rabbits 2150±50 (g) were mechanically tested in vitro. Mechanical tests, consisting of uniaxial loading on tissue samples oriented along the craneo-caudal and the perpendicular directions, respectively, revealed the anisotropic non-linear mechanical behaviour of the abdominal tissues. Experiments were performed considering the composite muscle (including external oblique-EO, internal oblique-IO and transverse abdominis-TA muscle layers), as well as separated muscle layers (i.e., external oblique, and the bilayer formed by internal oblique and transverse abdominis). Both the EO muscle layer and the IO-TA bilayer demonstrated a stiffer behaviour along the transversal direction to muscle fibres than along the longitudinal one. The fibre arrangement was measured by means of a histological study which confirmed that collagen fibres are mainly responsible for the passive mechanical strength and stiffness. Furthermore, the degree of anisotropy of the abdominal composite muscle turned out to be less pronounced than those obtained while studying the EO and IO-TA separately. Moreover, a phenomenological constitutive law was used to capture the measured experimental curves. A Levenberg-Marquardt optimization algorithm was used to fit the model constants to reproduce the experimental curves. Copyright © 2010 Elsevier Ltd. All rights reserved.

Malaria parasite evasion of classical complement pathway attack

DEFF Research Database (Denmark)

Larsen, Mads Delbo; Ditlev, Sisse; Olmos, Rafael Bayarri

2017-01-01

of the protective antibodies that are gradually acquired in response to P. falciparum-IEs. Although this response is dominated by IgG1 and IgG3, complement-mediated attack following activation of the classical pathway does not appear to be a major effector mechanism. We hypothesized that this is related to the knob...... is that the knob-restricted expression of PfEMP1 on the IE surface may serve as a hitherto unappreciated immune evasion mechanism employed by P. falciparum parasites....

Females use self-referent cues to avoid mating with previous mates.

Science.gov (United States)

Ivy, Tracie M; Weddle, Carie B; Sakaluk, Scott K

2005-12-07

Females of many species mate repeatedly throughout their lives, often with many different males (polyandry). Females can secure genetic benefits by maximizing their diversity of mating partners, and might be expected, therefore, to forego matings with previous partners in favour of novel males. Indeed, a female preference for novel mating partners has been shown in several taxa, but the mechanism by which females distinguish between novel males and previous mates remains unknown. We show that female crickets (Gryllodes sigillatus) mark males with their own unique chemical signatures during mating, enabling females to recognize prior mates in subsequent encounters and to avoid remating with them. Because self-referent chemosensory cues provide females with a simple, but reliable mechanism of identifying individuals with whom they have mated without requiring any special cognitive ability, they may be a widespread means by which females across a broad range of animal mating systems maximize the genetic benefits of polyandry.

Hormone profile in juvenile systemic lupus erythematosus with previous or current amenorrhea

NARCIS (Netherlands)

Silva, Clovis A.; Deen, Maria E. J.; Febronio, Marilia V.; Oliveira, Sheila K.; Terreri, Maria T.; Sacchetti, Silvana B.; Sztajnbok, Flavio R.; Marini, Roberto; Quintero, Maria V.; Bica, Blanca E.; Pereira, Rosa M.; Bonfa, Eloisa; Ferriani, Virginia P.; Robazzi, Teresa C.; Magalhaes, Claudia S.; Hilario, Maria O.

To identify the underlying mechanism of amenorrhea in juvenile systemic lupus erythematosus (JSLE) patients, thirty-five (11.7%) JSLE patients with current or previous amenorrhea were consecutively selected among the 298 post-menarche patients followed in 12 Brazilian pediatric rheumatology centers.

Transcriptomic analysis in a Drosophila model identifies previously implicated and novel pathways in the therapeutic mechanism in neuropsychiatric disorders

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Priyanka eSingh

2011-03-01

Full Text Available We have taken advantage of a newly described Drosophila model to gain insights into the potential mechanism of antiepileptic drugs (AEDs, a group of drugs that are widely used in the treatment of several neurological and psychiatric conditions besides epilepsy. In the recently described Drosophila model that is inspired by pentylenetetrazole (PTZ induced kindling epileptogenesis in rodents, chronic PTZ treatment for seven days causes a decreased climbing speed and an altered CNS transcriptome, with the latter mimicking gene expression alterations reported in epileptogenesis. In the model, an increased climbing speed is further observed seven days after withdrawal from chronic PTZ. We used this post-PTZ withdrawal regime to identify potential AED mechanism. In this regime, treatment with each of the five AEDs tested, namely, ethosuximide (ETH, gabapentin (GBP, vigabatrin (VGB, sodium valproate (NaVP and levetiracetam (LEV, resulted in rescuing of the altered climbing behavior. The AEDs also normalized PTZ withdrawal induced transcriptomic perturbation in fly heads; whereas AED untreated flies showed a large number of up- and down-regulated genes which were enriched in several processes including gene expression and cell communication, the AED treated flies showed differential expression of only a small number of genes that did not enrich gene expression and cell communication processes. Gene expression and cell communication related upregulated genes in AED untreated flies overrepresented several pathways - spliceosome, RNA degradation, and ribosome in the former category, and inositol phosphate metabolism, phosphatidylinositol signaling, endocytosis and hedgehog signaling in the latter. Transcriptome remodeling effect of AEDs was overall confirmed by microarray clustering that clearly separated the profiles of AED treated and untreated flies. Besides being consistent with previously implicated pathways, our results provide evidence for a role of

Revisiting telegony : Offspring inherit an acquired characteristic of their mother's previous mate

NARCIS (Netherlands)

Crean, Angela J.; Kopps, Anna M.; Bonduriansky, Russell

2014-01-01

Newly discovered non-genetic mechanisms break the link between genes and inheritance, thereby also raising the possibility that previous mating partners could influence traits in offspring sired by subsequent males that mate with the same female (‘telegony’). In the fly Telostylinus angusticollis,

KSb(OH) samples previously treated with Co y - rays irradiated with neutrons

Energy Technology Data Exchange (ETDEWEB)

Facetti, J F [Asuncion Nacional Univ. (Paraguay). Inst. de Ciencias

1969-01-01

When Ksb (OH) samples previously treated with Co y - rays or crushed are irradiated with neutrons, the yield of Sb and the annealing mechanism are apparently modified by the pretreatment. In addition it is shown that metastable species of Sb are formed under irradiation.

Epigenetic landscapes reveal transcription factors regulating CD8+ T cell differentiation

Science.gov (United States)

Yu, Bingfei; Zhang, Kai; Milner, J. Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P.; Pereira, Renata M.; Crotty, Shane; Chang, John T.; Pipkin, Matthew E.; Wang, Wei; Goldrath, Ananda W.

2017-01-01

Dynamic changes in the expression of transcription factors (TFs) can influence specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TF among differentially-fated precursor cells suggests additional underlying mechanisms. Here, we profiled genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that TF expression and binding contributed to establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal novel TFs influencing the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector and memory-precursor cell-fates, respectively. Our data define the epigenetic landscape of differentiation intermediates, facilitating identification of TFs with previously unappreciated roles in CD8+ T cell differentiation. PMID:28288100

Follicular helper T cells promote liver pathology in mice during Schistosoma japonicum infection.

Directory of Open Access Journals (Sweden)

Xiaojun Chen

2014-05-01

Full Text Available Following Schistosoma japonicum (S. japonicum infection, granulomatous responses are induced by parasite eggs trapped in host organs, particular in the liver, during the acute stage of disease. While excessive liver granulomatous responses can lead to more severe fibrosis and circulatory impairment in chronically infected host. However, the exact mechanism of hepatic granuloma formation has remained obscure. In this study, we for the first time showed that follicular helper T (Tfh cells are recruited to the liver to upregulate hepatic granuloma formation and liver injury in S. japonicum-infected mice, and identified a novel function of macrophages in Tfh cell induction. In addition, our results showed that the generation of Tfh cells driven by macrophages is dependent on cell-cell contact and the level of inducible costimulator ligand (ICOSL on macrophages which is regulated by CD40-CD40L signaling. Our findings uncovered a previously unappreciated role for Tfh cells in liver pathology caused by S. japonicum infection in mice.

Pharmacologic perspectives of functional selectivity by the angiotensin II type 1 receptor

DEFF Research Database (Denmark)

Aplin, Mark; Christensen, Gitte Lund; Hansen, Jakob Lerche

2008-01-01

and to sudden injury occurring in the circulatory system. Hence, current drugs that block all AT(1) receptor actions most likely leave room for improvement. Recent developments show that two major signaling pathways used by the AT(1) receptor may be dissected by pharmacologic means. Key pathologic responses...... protein actions and simultaneous activation of G protein-dependent or -independent signaling could therefore be desirable in certain situations. The previously unappreciated concept of "functional selectivity" makes this exact strategy feasible and may yield improved drugs for cardiovascular therapy....

Manufacturing of Nanostructured Rings from Previously ECAE-Processed AA5083 Alloy by Isothermal Forging

Directory of Open Access Journals (Sweden)

C. J. Luis

2013-01-01

Full Text Available The manufacturing of a functional hollow mechanical element or ring of the AA5083 alloy previously equal channel angular extrusion (ECAE processed, which presents a submicrometric microstructure, is dealt with. For this purpose, the design of two isothermal forging dies (preform and final shape is carried out using the design of experiments (DOE methodology. Moreover, after manufacturing the dies and carrying out tests so as to achieve real rings, the mechanical properties of these rings are analysed as well as their microstructure. Furthermore, a comparison between the different forged rings is made from ECAE-processed material subjected to different heat treatments, previous to the forging stage. On the other hand, the ring forging process is modelled through the use of finite element simulation in order to improve the die design and to study the force required for the isothermal forging, the damage value, and the strain the material predeformed by ECAE has undergone. With this present research work, it is intended to improve the knowledge about the mechanical properties of nanostructured material and the applicability of this material to industrial processes that allow the manufacturing of functional parts.

Feedback control stabilization of critical dynamics via resource transport on multilayer networks: How glia enable learning dynamics in the brain

Science.gov (United States)

Virkar, Yogesh S.; Shew, Woodrow L.; Restrepo, Juan G.; Ott, Edward

2016-10-01

Learning and memory are acquired through long-lasting changes in synapses. In the simplest models, such synaptic potentiation typically leads to runaway excitation, but in reality there must exist processes that robustly preserve overall stability of the neural system dynamics. How is this accomplished? Various approaches to this basic question have been considered. Here we propose a particularly compelling and natural mechanism for preserving stability of learning neural systems. This mechanism is based on the global processes by which metabolic resources are distributed to the neurons by glial cells. Specifically, we introduce and study a model composed of two interacting networks: a model neural network interconnected by synapses that undergo spike-timing-dependent plasticity; and a model glial network interconnected by gap junctions that diffusively transport metabolic resources among the glia and, ultimately, to neural synapses where they are consumed. Our main result is that the biophysical constraints imposed by diffusive transport of metabolic resources through the glial network can prevent runaway growth of synaptic strength, both during ongoing activity and during learning. Our findings suggest a previously unappreciated role for glial transport of metabolites in the feedback control stabilization of neural network dynamics during learning.

HEART TRANSPLANTATION IN PATIENTS WITH PREVIOUS OPEN HEART SURGERY

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R. Sh. Saitgareev

2016-01-01

Full Text Available Heart Transplantation (HTx to date remains the most effective and radical method of treatment of patients with end-stage heart failure. The defi cit of donor hearts is forcing to resort increasingly to the use of different longterm mechanical circulatory support systems, including as a «bridge» to the follow-up HTx. According to the ISHLT Registry the number of recipients underwent cardiopulmonary bypass surgery increased from 40% in the period from 2004 to 2008 to 49.6% for the period from 2009 to 2015. HTx performed in repeated patients, on the one hand, involves considerable technical diffi culties and high risks; on the other hand, there is often no alternative medical intervention to HTx, and if not dictated by absolute contradictions the denial of the surgery is equivalent to 100% mortality. This review summarizes the results of a number of published studies aimed at understanding the immediate and late results of HTx in patients, previously underwent open heart surgery. The effect of resternotomy during HTx and that of the specifi c features associated with its implementation in recipients previously operated on open heart, and its effects on the immediate and long-term survival were considered in this review. Results of studies analyzing the risk factors for perioperative complications in repeated recipients were also demonstrated. Separately, HTx risks after implantation of prolonged mechanical circulatory support systems were examined. The literature does not allow to clearly defi ning the impact factor of earlier performed open heart surgery on the course of perioperative period and on the prognosis of survival in recipients who underwent HTx. On the other hand, subject to the regular fl ow of HTx and the perioperative period the risks in this clinical situation are justifi ed as a long-term prognosis of recipients previously conducted open heart surgery and are comparable to those of patients who underwent primary HTx. Studies

Publisher Correction: Single-cell analysis of experience-dependent transcriptomic states in the mouse visual cortex.

Science.gov (United States)

Hrvatin, Sinisa; Hochbaum, Daniel R; Nagy, M Aurel; Cicconet, Marcelo; Robertson, Keiramarie; Cheadle, Lucas; Zilionis, Rapolas; Ratner, Alex; Borges-Monroy, Rebeca; Klein, Allon M; Sabatini, Bernardo L; Greenberg, Michael E

2018-05-11

In the version of this article initially published, the x-axis labels in Fig. 3c read Vglut, Gad1/2, Aldh1l1 and Pecam1; they should have read Vglut + , Gad1/2 + , Aldh1l1 + and Pecam1 + . In Fig. 4, the range values were missing from the color scales; they are, from left to right, 4-15, 0-15, 4-15 and 0-15 in Fig. 4a and 4-15, 4-15 and 4-8 in Fig. 4h. In the third paragraph of the main text, the phrase reading "Previous approaches have analyzed a limited number of inhibitory cell types, thus masking the full diversity of excitatory populations" should have read "Previous approaches have analyzed a limited number of inhibitory cell types and masked the full diversity of excitatory populations." In the second paragraph of Results section "Diversity of experience-regulated ERGs," the phrase reading "thus suggesting considerable divergence within the gene expression program responding to early stimuli" should have read "thus suggesting considerable divergence within the early stimulus-responsive gene expression program." In the fourth paragraph of Results section "Excitatory neuronal LRGs," the sentence reading "The anatomical organization of these cell types into sublayers, coupled with divergent transcriptional responses to a sensory stimulus, suggested previously unappreciated functional subdivisions located within the laminae of the mouse visual cortex and resembling the cytoarchitecture in higher mammals" should have read "The anatomical organization of these cell types into sublayers, coupled with divergent transcriptional responses to a sensory stimulus, suggests previously unappreciated functional subdivisions located within the laminae of the mouse visual cortex, resembling the cytoarchitecture in higher mammals." In the last sentence of the Results, "sensory-responsive genes" should have read "sensory-stimulus-responsive genes." The errors have been corrected in the HTML and PDF versions of the article.

The Pseudomonas aeruginosa Type III Translocon Is Required for Biofilm Formation at the Epithelial Barrier

DEFF Research Database (Denmark)

Tran, Cindy S; Rangel, Stephanie M; Almblad, Henrik

2014-01-01

Clinical infections by Pseudomonas aeruginosa, a deadly Gram-negative, opportunistic pathogen of immunocompromised hosts, often involve the formation of antibiotic-resistant biofilms. Although biofilm formation has been extensively studied in vitro on glass or plastic surfaces, much less is known...... about biofilm formation at the epithelial barrier. We have previously shown that when added to the apical surface of polarized epithelial cells, P. aeruginosa rapidly forms cell-associated aggregates within 60 minutes of infection. By confocal microscopy we now show that cell-associated aggregates...... a previously unappreciated function for the type III translocon in the formation of P. aeruginosa biofilms at the epithelial barrier and demonstrate that biofilms may form at early time points of infection....

Impaired Epstein-Barr Virus-Specific Neutralizing Antibody Response during Acute Infectious Mononucleosis Is Coincident with Global B-Cell Dysfunction.

Science.gov (United States)

Panikkar, Archana; Smith, Corey; Hislop, Andrew; Tellam, Nick; Dasari, Vijayendra; Hogquist, Kristin A; Wykes, Michelle; Moss, Denis J; Rickinson, Alan; Balfour, Henry H; Khanna, Rajiv

2015-09-01

Here we present evidence for previously unappreciated B-cell immune dysregulation during acute Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Longitudinal analyses revealed that patients with acute IM have undetectable EBV-specific neutralizing antibodies and gp350-specific B-cell responses, which were associated with a significant reduction in memory B cells and no evidence of circulating antibody-secreting cells. These observations correlate with dysregulation of tumor necrosis factor family members BAFF and APRIL and increased expression of FAS on circulating B cells. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Continuum Mechanics

CERN Document Server

Romano, Antonio

2010-01-01

This book offers a broad overview of the potential of continuum mechanics to describe a wide range of macroscopic phenomena in real-world problems. Building on the fundamentals presented in the authors' previous book, Continuum Mechanics using Mathematica(R), this new work explores interesting models of continuum mechanics, with an emphasis on exploring the flexibility of their applications in a wide variety of fields.Specific topics, which have been chosen to show the power of continuum mechanics to characterize the experimental behavior of real phenomena, include: * various aspects of nonlin

Farmacovigilancia: Una herramienta poco utilizada Pharmacoepidemiology: An unappreciated tool

Directory of Open Access Journals (Sweden)

Walter Vasen

2006-06-01

Full Text Available La farmacovigilacia es una herramienta esencial para el control de los fármacos utilizados en nuestro país, el presente artículo muestra una revisión de los elementos más destacados en el tema y un resumen de los sistemas regulatorios vigentes en la Argentina y de la experiencia de la Red de Farmacovigilancia de los hospitales del Gobierno de la Ciudad de Buenos Aires, con el objetivo de informar y estimular a los colegas a la denuncia de los efectos adversos de los medicamentos.Pharmacoepidemiology is an essential tool for controlling drugs used in our country. The present article reveals the most relevant aspects on the topic, summarizes regulatory tools currently used in Argentina and explores the experience of the Pharmacoepidemiology Network in public hospitals of Buenos Aires City. The aim is to inform and stimulate colleagues to report adverse effects of drugs.

Risk management - unappreciated instrument of supply chain management strategy

OpenAIRE

Wojciech Machowiak

2012-01-01

Background: Unlike Enterprise Risk Management, which is certainly quite well rooted in business practice, Supply Chain Risk Management (SCRM) still continues to be dynamically developing subject of academic research, whereas its practical applications are rather scarce. Material and methods: On the basis of broad review of the current state of the art in world literature, significant  relevancies to the core processes and enterprise strategy are discussed.   Results: ...

Risk management - unappreciated instrument of supply chain management strategy

Directory of Open Access Journals (Sweden)

Wojciech Machowiak

2012-12-01

Full Text Available Background: Unlike Enterprise Risk Management, which is certainly quite well rooted in business practice, Supply Chain Risk Management (SCRM still continues to be dynamically developing subject of academic research, whereas its practical applications are rather scarce. Material and methods: On the basis of broad review of the current state of the art in world literature, significant  relevancies to the core processes and enterprise strategy are discussed.   Results: The paper shows some interesting from the enterprise's performance and competitiveness point of view additional benefits, potentially resulting from the proactive, consistent and effective implementation of the SCRM system. Conclusions: Some additional advantages from proactive supply chain risk management account for perceiving SCRM as multifunctional instrument of strategic SC management, exceeding established understanding RM as security and threat-prevention  tool only. Positive influence from SCRM onto SC performance and competitiveness can make reasonable to enhance its position within SCM strategy.

Laparoscopy After Previous Laparotomy

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Zulfo Godinjak

2006-11-01

Full Text Available Following the abdominal surgery, extensive adhesions often occur and they can cause difficulties during laparoscopic operations. However, previous laparotomy is not considered to be a contraindication for laparoscopy. The aim of this study is to present that an insertion of Veres needle in the region of umbilicus is a safe method for creating a pneumoperitoneum for laparoscopic operations after previous laparotomy. In the last three years, we have performed 144 laparoscopic operations in patients that previously underwent one or two laparotomies. Pathology of digestive system, genital organs, Cesarean Section or abdominal war injuries were the most common causes of previouslaparotomy. During those operations or during entering into abdominal cavity we have not experienced any complications, while in 7 patients we performed conversion to laparotomy following the diagnostic laparoscopy. In all patients an insertion of Veres needle and trocar insertion in the umbilical region was performed, namely a technique of closed laparoscopy. Not even in one patient adhesions in the region of umbilicus were found, and no abdominal organs were injured.

Perivalvular pannus and valve thrombosis: two concurrent mechanisms of mechanical valve prosthesis dysfunction.

Science.gov (United States)

Arnáiz-García, María Elena; González-Santos, Jose María; Bueno-Codoñer, María E; López-Rodríguez, Javier; Dalmau-Sorlí, María José; Arévalo-Abascal, Adolfo; Arribas-Jiménez, Antonio; Diego-Nieto, Alejandro; Rodríguez-Collado, Javier; Rodríguez-López, Jose María

2015-02-01

A 78-year-old woman was admitted to our institution with progressive dyspnea. She had previously been diagnosed with rheumatic heart disease and had undergone cardiac surgery for mechanical mitral valve replacement ten years previously. Transesophageal echocardiography revealed blockage of the mechanical prosthesis and the patient was scheduled for surgery, in which a thrombus was removed from the left atrial appendage. A partial thrombosis of the mechanical prosthesis and circumferential pannus overgrowth were concomitantly detected. Prosthetic heart valve blockage is a rare but life-threatening complication, the main causes of which are thrombosis and pannus formation. The two conditions are different but both are usually misdiagnosed. Two concurrent mechanisms of prosthesis blockage were found in this patient. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Preoperative screening: value of previous tests.

Science.gov (United States)

Macpherson, D S; Snow, R; Lofgren, R P

1990-12-15

To determine the frequency of tests done in the year before elective surgery that might substitute for preoperative screening tests and to determine the frequency of test results that change from a normal value to a value likely to alter perioperative management. Retrospective cohort analysis of computerized laboratory data (complete blood count, sodium, potassium, and creatinine levels, prothrombin time, and partial thromboplastin time). Urban tertiary care Veterans Affairs Hospital. Consecutive sample of 1109 patients who had elective surgery in 1988. At admission, 7549 preoperative tests were done, 47% of which duplicated tests performed in the previous year. Of 3096 previous results that were normal as defined by hospital reference range and done closest to the time of but before admission (median interval, 2 months), 13 (0.4%; 95% CI, 0.2% to 0.7%), repeat values were outside a range considered acceptable for surgery. Most of the abnormalities were predictable from the patient's history, and most were not noted in the medical record. Of 461 previous tests that were abnormal, 78 (17%; CI, 13% to 20%) repeat values at admission were outside a range considered acceptable for surgery (P less than 0.001, frequency of clinically important abnormalities of patients with normal previous results with those with abnormal previous results). Physicians evaluating patients preoperatively could safely substitute the previous test results analyzed in this study for preoperative screening tests if the previous tests are normal and no obvious indication for retesting is present.

Isotropic actomyosin dynamics promote organization of the apical cell cortex in epithelial cells.

Science.gov (United States)

Klingner, Christoph; Cherian, Anoop V; Fels, Johannes; Diesinger, Philipp M; Aufschnaiter, Roland; Maghelli, Nicola; Keil, Thomas; Beck, Gisela; Tolić-Nørrelykke, Iva M; Bathe, Mark; Wedlich-Soldner, Roland

2014-10-13

Although cortical actin plays an important role in cellular mechanics and morphogenesis, there is surprisingly little information on cortex organization at the apical surface of cells. In this paper, we characterize organization and dynamics of microvilli (MV) and a previously unappreciated actomyosin network at the apical surface of Madin-Darby canine kidney cells. In contrast to short and static MV in confluent cells, the apical surfaces of nonconfluent epithelial cells (ECs) form highly dynamic protrusions, which are often oriented along the plane of the membrane. These dynamic MV exhibit complex and spatially correlated reorganization, which is dependent on myosin II activity. Surprisingly, myosin II is organized into an extensive network of filaments spanning the entire apical membrane in nonconfluent ECs. Dynamic MV, myosin filaments, and their associated actin filaments form an interconnected, prestressed network. Interestingly, this network regulates lateral mobility of apical membrane probes such as integrins or epidermal growth factor receptors, suggesting that coordinated actomyosin dynamics contributes to apical cell membrane organization. © 2014 Klingner et al.

Epigenetic landscapes reveal transcription factors that regulate CD8+ T cell differentiation.

Science.gov (United States)

Yu, Bingfei; Zhang, Kai; Milner, J Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P; Pereira, Renata M; Crotty, Shane; Chang, John T; Pipkin, Matthew E; Wang, Wei; Goldrath, Ananda W

2017-05-01

Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8 + T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8 + T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8 + T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8 + T cell differentiation.

Functional genomics tools applied to plant metabolism: a survey on plant respiration, its connections and the annotation of complex gene functions

Directory of Open Access Journals (Sweden)

Wagner L. Araújo

2012-09-01

Full Text Available The application of post-genomic techniques in plant respiration studies has greatly improved our ability to assign functions to gene products. In addition it has also revealed previously unappreciated interactions between distal elements of metabolism. Such results have reinforced the need to consider plant respiratory metabolism as part of a complex network and making sense of such interactions will ultimately require the construction of predictive and mechanistic models. Transcriptomics, proteomics, metabolomics and the quantification of metabolic flux will be of great value in creating such models both by facilitating the annotation of complex gene function, determining their structure and by furnishing the quantitative data required to test them. In this review we highlight how these experimental approaches have contributed to our current understanding of plant respiratory metabolism and its interplay with associated process (e.g. photosynthesis, photorespiration and nitrogen metabolism. We also discuss how data from these techniques may be integrated, with the ultimate aim of identifying mechanisms that control and regulate plant respiration and discovering novel gene functions with potential biotechnological implications.

SEC24A deficiency lowers plasma cholesterol through reduced PCSK9 secretion

Science.gov (United States)

Chen, Xiao-Wei; Wang, He; Bajaj, Kanika; Zhang, Pengcheng; Meng, Zhuo-Xian; Ma, Danjun; Bai, Yongsheng; Liu, Hui-Hui; Adams, Elizabeth; Baines, Andrea; Yu, Genggeng; Sartor, Maureen A; Zhang, Bin; Yi, Zhengping; Lin, Jiandie; Young, Stephen G; Schekman, Randy; Ginsburg, David

2013-01-01

The secretory pathway of eukaryotic cells packages cargo proteins into COPII-coated vesicles for transport from the endoplasmic reticulum (ER) to the Golgi. We now report that complete genetic deficiency for the COPII component SEC24A is compatible with normal survival and development in the mouse, despite the fundamental role of SEC24 in COPII vesicle formation and cargo recruitment. However, these animals exhibit markedly reduced plasma cholesterol, with mutations in Apoe and Ldlr epistatic to Sec24a, suggesting a receptor-mediated lipoprotein clearance mechanism. Consistent with these data, hepatic LDLR levels are up-regulated in SEC24A-deficient cells as a consequence of specific dependence of PCSK9, a negative regulator of LDLR, on SEC24A for efficient exit from the ER. Our findings also identify partial overlap in cargo selectivity between SEC24A and SEC24B, suggesting a previously unappreciated heterogeneity in the recruitment of secretory proteins to the COPII vesicles that extends to soluble as well as trans-membrane cargoes. DOI: http://dx.doi.org/10.7554/eLife.00444.001 PMID:23580231

Quantum Mechanics/Molecular Mechanics Modeling of Drug Metabolism

DEFF Research Database (Denmark)

Lonsdale, Richard; Fort, Rachel M; Rydberg, Patrik

2016-01-01

)-mexiletine in CYP1A2 with hybrid quantum mechanics/molecular mechanics (QM/MM) methods, providing a more detailed and realistic model. Multiple reaction barriers have been calculated at the QM(B3LYP-D)/MM(CHARMM27) level for the direct N-oxidation and H-abstraction/rebound mechanisms. Our calculated barriers......The mechanism of cytochrome P450(CYP)-catalyzed hydroxylation of primary amines is currently unclear and is relevant to drug metabolism; previous small model calculations have suggested two possible mechanisms: direct N-oxidation and H-abstraction/rebound. We have modeled the N-hydroxylation of (R...... indicate that the direct N-oxidation mechanism is preferred and proceeds via the doublet spin state of Compound I. Molecular dynamics simulations indicate that the presence of an ordered water molecule in the active site assists in the binding of mexiletine in the active site...

Attachment security as a mechanism linking foster care placement to improved mental health outcomes in previously institutionalized children.

Science.gov (United States)

McLaughlin, Katie A; Zeanah, Charles H; Fox, Nathan A; Nelson, Charles A

2012-01-01

Children reared in institutions experience elevated rates of psychiatric disorders. Inability to form a secure attachment relationship to a primary caregiver is posited to be a central mechanism in this association. We determined whether the ameliorative effect of a foster care (FC) intervention on internalizing disorders in previously institutionalized children was explained by the development of secure attachment among children placed in FC. Second we evaluated the role of lack of attachment in an institutionalized sample on the etiology of internalizing disorders within the context of a randomized trial. A sample of 136 children (aged 6-30 months) residing in institutions was recruited in Bucharest, Romania. Children were randomized to FC (n = 68) or to care as usual (CAU; n = 68). Foster parents were recruited, trained, and overseen by the investigative team. Attachment security at 42 months was assessed using the Strange Situation Procedure, and internalizing disorders at 54 months were assessed using the Preschool Age Psychiatric Assessment. Girls in FC had fewer internalizing disorders than girls in CAU (OR = 0.17, p = .006). The intervention had no effect on internalizing disorders in boys (OR = 0.47, p = .150). At 42 months, girls in FC were more likely to have secure attachment than girls in CAU (OR = 12.5, p security predicted lower rates of internalizing disorders in both sexes. Development of attachment security fully mediated intervention effects on internalizing disorders in girls. Placement into FC facilitated the development of secure attachment and prevented the onset of internalizing disorders in institutionalized girls. The differential effects of FC on attachment security in boys and girls explained gender differences in the intervention effects on psychopathology. Findings provide evidence for the critical role of disrupted attachment in the etiology of internalizing disorders in children exposed to institutionalization. © 2011 The Authors

Difficulties with inflationary cosmology

International Nuclear Information System (INIS)

Penrose, R.

1989-01-01

According to the author, the idea of inflationary cosmology is an ingenious attempt to solve some of the major puzzles of cosmology, most notably the flatness problem, the homogeneity (horizon) problem, and the monopole problem. The homogeneity problem, in particular, is intimately connected with a largely unappreciated, but profound puzzle presented by the second law of thermodynamics. The author argues that the mechanism of inflation does not, by itself, come to terms with this and consequently, comes nowhere close to providing an understanding of the large-scale homogeneity of the universe

Hyponatraemia and hypothyroidism in a previously irradiated case of carcinoma of the tongue

International Nuclear Information System (INIS)

Nasser, N.A.; Lever, E.G.

1987-01-01

A case of squamous cell carcinoma of the tongue was complicated by post operative hyponatraemia. The criteria for the syndrome of inappropriate secretion of anti diuretic hormone, (ADH) (SIADH) were met but the patient remained hyponatraemic despite adequate treatment. The patient had previously received radical external radiotherapy to the neck and was found to be profoundly hypothyroid. Correction of the hypothyroid state led to clinical and biochemical recovery. The frequency of post-irradiation hypothyroidism and the possible mechanisms of hypothyroid-induced hyponatraemia are discussed. (author)

Abnormal flow behavior and necklace microstructure of powder metallurgy superalloys with previous particle boundaries (PPBs)

Energy Technology Data Exchange (ETDEWEB)

Ning, Yongquan, E-mail: luckyning@nwpu.edu.cn [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Zhou, Cong; Liang, Houquan [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Fu, M.W., E-mail: mmmwfu@polyu.edu.hk [Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)

2016-01-15

Powder metallurgy (P/M) has been introduced as an innovative process to manufacture high performance components with fine, homogenous and segregation-free microstructure. Unfortunately, previous particle boundary (PPB) precipitated during the powder metallurgy process. Since undesirable PPB is detrimental to mechanical properties, hot extrusion or/and isothermal forging are needed. In present research, isothermal compression tests were conducted on P/M FGH4096 superalloys with typical PPBs. Abnormal flow behavior during high-speed deformation has been quantitatively investigated. Caused by the competition mechanism between work-hardening and dynamic-softening, abnormal flow behaves typical four stages (viz., work-hardening, stable, softening and steady). Microstructure observation for hardening or/and softening mechanism has been investigated. Meanwhile, necklace microstructure was observed by scanning electron microscope, and the grain fraction analysis was performed by using electron backscatter diffraction. Transmission electron microscopy was used for characterizing the boundary structure. Necklace microstructural mechanism for processing P/M superalloys has been developed, and the dynamic recrystallization model has also been conducted. Bulge–corrugation model is the primary nucleation mechanism for P/M superalloys with PPBs. When PPB is entirely covered with new grains, necklace microstructure has formed. Bulge–corrugation mechanism can repeatedly take place in the following necklace DRX.

The Effects of the Previous Outcome on Probabilistic Choice in Rats

Science.gov (United States)

Marshall, Andrew T.; Kirkpatrick, Kimberly

2014-01-01

This study examined the effects of previous outcomes on subsequent choices in a probabilistic-choice task. Twenty-four rats were trained to choose between a certain outcome (1 or 3 pellets) versus an uncertain outcome (3 or 9 pellets), delivered with a probability of .1, .33, .67, and .9 in different phases. Uncertain outcome choices increased with the probability of uncertain food. Additionally, uncertain choices increased with the probability of uncertain food following both certain-choice outcomes and unrewarded uncertain choices. However, following uncertain-choice food outcomes, there was a tendency to choose the uncertain outcome in all cases, indicating that the rats continued to “gamble” after successful uncertain choices, regardless of the overall probability or magnitude of food. A subsequent manipulation, in which the probability of uncertain food varied within each session as a function of the previous uncertain outcome, examined how the previous outcome and probability of uncertain food affected choice in a dynamic environment. Uncertain-choice behavior increased with the probability of uncertain food. The rats exhibited increased sensitivity to probability changes and a greater degree of win–stay/lose–shift behavior than in the static phase. Simulations of two sequential choice models were performed to explore the possible mechanisms of reward value computations. The simulation results supported an exponentially decaying value function that updated as a function of trial (rather than time). These results emphasize the importance of analyzing global and local factors in choice behavior and suggest avenues for the future development of sequential-choice models. PMID:23205915

Researchers Find a Mechanism for Schizophrenia

Science.gov (United States)

... issue Health Capsule Researchers Find a Mechanism for Schizophrenia En español Send us your comments Scientists uncovered a mechanism behind genetic variations previously linked to schizophrenia. The findings may lead to new clinical approaches. ...

Detection of prion infectivity in fat tissues of scrapie-infected mice.

Directory of Open Access Journals (Sweden)

Brent Race

2008-12-01

Full Text Available Distribution of prion infectivity in organs and tissues is important in understanding prion disease pathogenesis and designing strategies to prevent prion infection in animals and humans. Transmission of prion disease from cattle to humans resulted in banning human consumption of ruminant nervous system and certain other tissues. In the present study, we surveyed tissue distribution of prion infectivity in mice with prion disease. We show for the first time detection of infectivity in white and brown fat. Since high amounts of ruminant fat are consumed by humans and also incorporated into animal feed, fat-containing tissues may pose a previously unappreciated hazard for spread of prion infection.

Conserved epitope on influenza-virus hemagglutinin head defined by a vaccine-induced antibody

Energy Technology Data Exchange (ETDEWEB)

Raymond, Donald D.; Bajic, Goran; Ferdman, Jack; Suphaphiphat, Pirada; Settembre, Ethan C.; Moody, M. Anthony; Schmidt, Aaron G.; Harrison, Stephen C. (Duke-MED); (CH-Boston); (Seqirus)

2017-12-18

Antigenic variation requires frequent revision of annual influenza vaccines. Next-generation vaccine design strategies aim to elicit a broader immunity by directing the human immune response toward conserved sites on the principal viral surface protein, the hemagglutinin (HA). We describe a group of antibodies that recognize a hitherto unappreciated, conserved site on the HA of H1 subtype influenza viruses. Mutations in that site, which required a change in the H1 component of the 2017 vaccine, had not previously “taken over” among circulating H1 viruses. Our results encourage vaccine design strategies that resurface a protein to focus the immune response on a specific region.

Bistable Mechanisms for Space Applications.

Science.gov (United States)

Zirbel, Shannon A; Tolman, Kyler A; Trease, Brian P; Howell, Larry L

2016-01-01

Compliant bistable mechanisms are monolithic devices with two stable equilibrium positions separated by an unstable equilibrium position. They show promise in space applications as nonexplosive release mechanisms in deployment systems, thereby eliminating friction and improving the reliability and precision of those mechanical devices. This paper presents both analytical and numerical models that are used to predict bistable behavior and can be used to create bistable mechanisms in materials not previously feasible for compliant mechanisms. Materials compatible with space applications are evaluated for use as bistable mechanisms and prototypes are fabricated in three different materials. Pin-puller and cutter release mechanisms are proposed as potential space applications.

A set of genes previously implicated in the hypoxia response might be an important modulator in the rat ear tissue response to mechanical stretch

Directory of Open Access Journals (Sweden)

Orgill Dennis

2007-11-01

Full Text Available Abstract Background Wounds are increasingly important in our aging societies. Pathologies such as diabetes predispose patients to chronic wounds that can cause pain, infection, and amputation. The vacuum assisted closure device shows remarkable outcomes in wound healing. Its mechanism of action is unclear despite several hypotheses advanced. We previously hypothesized that micromechanical forces can heal wounds. To understand better the biological response of soft tissue to forces, rat ears in vivo were stretched and their gene expression patterns over time obtained. The absolute enrichment (AE algorithm that obtains a combined up and down regulated picture of the expression analysis was implemented. Results With the use of AE, the hypoxia gene set was the most important at a highly significant level. A co-expression network analysis showed that important co-regulated members of the hypoxia pathway include a glucose transporter (slc2a8, heme oxygenase, and nitric oxide synthase2 among others. Conclusion It appears that the hypoxia pathway may be an important modulator of response of soft tissue to forces. This finding gives us insights not only into the underlying biology, but also into clinical interventions that could be designed to mimic within wounded tissue the effects of forces without all the negative effects that forces themselves create.

49 CFR 173.23 - Previously authorized packaging.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Previously authorized packaging. 173.23 Section... REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Preparation of Hazardous Materials for Transportation § 173.23 Previously authorized packaging. (a) When the regulations specify a packaging with a specification marking...

CD28 controls the development of innate-like CD8+ T cells by promoting the functional maturation of NKT cells.

Science.gov (United States)

Yousefi, Mitra; Duplay, Pascale

2013-11-01

NK T cells(NKT cells) share functional characteristics and homing properties that are distinct from conventional T cells. In this study, we investigated the contribution of CD28 in the functional development of γδ NKT and αβ NKT cells in mice. We show that CD28 promotes the thymic maturation of promyelocytic leukemia zinc finger(+) IL-4(+) NKT cells and upregulation of LFA-1 expression on NKT cells. We demonstrate that the developmental defect of γδ NKT cells in CD28-deficient mice is cell autonomous. Moreover, we show in both wild-type C57BL/6 mice and in downstream of tyrosine kinase-1 transgenic mice, a mouse model with increased numbers of γδ NKT cells, that CD28-mediated regulation of thymic IL-4(+) NKT cells promotes the differentiation of eomesodermin(+) CD44(high) innate-like CD8(+) T cells. These findings reveal a previously unappreciated mechanism by which CD28 controls NKT-cell homeostasis and the size of the innate-like CD8(+) T-cell pool. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Light-induced translocation of RGS9-1 and Gβ5L in mouse rod photoreceptors.

Directory of Open Access Journals (Sweden)

Mei Tian

Full Text Available The transducin GTPase-accelerating protein complex, which determines the photoresponse duration of photoreceptors, is composed of RGS9-1, Gβ5L and R9AP. Here we report that RGS9-1 and Gβ5L change their distribution in rods during light/dark adaptation. Upon prolonged dark adaptation, RGS9-1 and Gβ5L are primarily located in rod inner segments. But very dim-light exposure quickly translocates them to the outer segments. In contrast, their anchor protein R9AP remains in the outer segment at all times. In the dark, Gβ5L's interaction with R9AP decreases significantly and RGS9-1 is phosphorylated at S(475 to a significant degree. Dim light exposure leads to quick de-phosphorylation of RGS9-1. Furthermore, after prolonged dark adaptation, RGS9-1 and transducin Gα are located in different cellular compartments. These results suggest a previously unappreciated mechanism by which prolonged dark adaptation leads to increased light sensitivity in rods by dissociating RGS9-1 from R9AP and redistributing it to rod inner segments.

22 CFR 40.91 - Certain aliens previously removed.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a result...

Quantitative phosphoproteomics dissection of seven-transmembrane receptor signaling using full and biased agonists

DEFF Research Database (Denmark)

Christensen, Gitte L; Kelstrup, Christian D; Lyngsø, Christina

2010-01-01

(q)-dependent and -independent AT(1)R signaling. This study provides substantial novel insight into angiotensin II signal transduction and is the first study dissecting the differences between a full agonist and a biased agonist from a 7TMR on a systems-wide scale. Importantly, it reveals a previously unappreciated diversity......Seven-transmembrane receptors (7TMRs) signal through the well described heterotrimeric G proteins but can also activate G protein-independent signaling pathways of which the impact and complexity are less understood. The angiotensin II type 1 receptor (AT(1)R) is a prototypical 7TMR...... and quantity of Galpha(q) protein-independent signaling and uncovers novel signaling pathways. We foresee that the amount and diversity of G protein-independent signaling may be more pronounced than previously recognized for other 7TMRs as well. Quantitative mass spectrometry is a promising tool for evaluation...

Genomic interrogation of mechanism(s) underlying cellular responses to toxicants

International Nuclear Information System (INIS)

Amin, Rupesh P.; Hamadeh, Hisham K.; Bushel, Pierre R.; Bennett, Lee; Afshari, Cynthia A.; Paules, Richard S.

2002-01-01

Assessment of the impact of xenobiotic exposure on human health and disease progression is complex. Knowledge of mode(s) of action, including mechanism(s) contributing to toxicity and disease progression, is valuable for evaluating compounds. Toxicogenomics, the subdiscipline which merges genomics with toxicology, holds the promise to contributing significantly toward the goal of elucidating mechanism(s) by studying genome-wide effects of xenobiotics. Global gene expression profiling, revolutionized by microarray technology and a crucial aspect of a toxicogenomic study, allows measuring transcriptional modulation of thousands of genes following exposure to a xenobiotic. We use our results from previous studies on compounds representing two different classes of xenobiotics (barbiturate and peroxisome proliferator) to discuss the application of computational approaches for analyzing microarray data to elucidate mechanism(s) underlying cellular responses to toxicants. In particular, our laboratory demonstrated that chemical-specific patterns of gene expression can be revealed using cDNA microarrays. Transcript profiling provides discrimination between classes of toxicants, as well as, genome-wide insight into mechanism(s) of toxicity and disease progression. Ultimately, the expectation is that novel approaches for predicting xenobiotic toxicity in humans will emerge from such information

Toward a microrealistic version of quantum mechanics. II

International Nuclear Information System (INIS)

Maxwell, N.

1976-01-01

Possible objections to the propensity microrealistic version of quantum mechanics proposed previously are answered. This version of quantum mechanics is compared with the statistical, particle, microrealistic viewpoint, and a crucial experiment is proposed designed to distinguish between these two microrealistic versions of quantum mechanics

Multispecies Coevolution Particle Swarm Optimization Based on Previous Search History

Directory of Open Access Journals (Sweden)

Danping Wang

2017-01-01

Full Text Available A hybrid coevolution particle swarm optimization algorithm with dynamic multispecies strategy based on K-means clustering and nonrevisit strategy based on Binary Space Partitioning fitness tree (called MCPSO-PSH is proposed. Previous search history memorized into the Binary Space Partitioning fitness tree can effectively restrain the individuals’ revisit phenomenon. The whole population is partitioned into several subspecies and cooperative coevolution is realized by an information communication mechanism between subspecies, which can enhance the global search ability of particles and avoid premature convergence to local optimum. To demonstrate the power of the method, comparisons between the proposed algorithm and state-of-the-art algorithms are grouped into two categories: 10 basic benchmark functions (10-dimensional and 30-dimensional, 10 CEC2005 benchmark functions (30-dimensional, and a real-world problem (multilevel image segmentation problems. Experimental results show that MCPSO-PSH displays a competitive performance compared to the other swarm-based or evolutionary algorithms in terms of solution accuracy and statistical tests.

Survival rate of Plodia interpunctella (Lepidoptera: Pyralidae: On different states of wheat and rye kernels previously infested by beetle pests

Directory of Open Access Journals (Sweden)

Vukajlović Filip N.

2017-01-01

Full Text Available The present study was undertaken to determine survival rate of Plodia interpunctella (Hübner, 1813, reared on different mechanical states of Vizija winter wheat cultivar and Raša winter rye cultivar, previously infested with different beetle pests. Wheat was previously infested with Rhyzopertha dominica, Sitophilus granarius, Oryzaephilus surinamensis and Cryptolestes ferrugineus, while rye was infested only with O. surinamensis. Kernels were tested in three different mechanical states: (A whole undamaged kernels; (B kernels already damaged by pests and (C original storage kernels (mixture of B and C type. No P. interpunctella adult emerged on wheat kernels, while 36 adults developed on rye kernels. The highest abundance reached beetle species who fed with a mixture of kernels damaged by pests and whole undamaged kernels. Development and survival rate of five different storage insect pests depends on type of kernels and there exist significant survivorship correlations among them.

Thermal stability of the tokamak plasma edge

International Nuclear Information System (INIS)

Stacey, W.M.

1997-01-01

The general linear, fluid, thermal instability theory for the plasma edge has been extended. An analysis of a two-dimensional fluid model of the plasma edge has identified the importance of many previously unappreciated phenomena associated with parallel and gyroviscous forces in the presence of large radial gradients, with large radial or parallel flows, with the temperature dependence of transport coefficients, and with the coupling of temperature, flow and density perturbations. The radiative condensation effect is generalized to include a further destabilizing condensation effect associated with radial heat conduction. Representative plasma edge neutral and impurity densities are found to be capable of driving thermal instabilities in the edge transport barrier and radiative mantle, respectively. (author)

Enhanced wetting of Cu on ZnO by migration of subsurface oxygen vacancies

DEFF Research Database (Denmark)

Beinik, Igor; Helström, Matti; Jensen, Thomas Nørregaard

2015-01-01

is of utmost importance. The Cu/ZnO system is among the most investigated of such systems in model studies, but the presence of subsurface ZnO defects and their important role for adhesion on ZnO have been unappreciated so far. Here we reveal that the surface-directed migration of subsurface defects affects...... the Cu adhesion on polar ZnO(0001) in the technologically interesting temperature range up to 550 K. This leads to enhanced adhesion and ultimately complete wetting of ZnO(0001) by a Cu overlayer. On the basis of our experimental and computational results we demonstrate a mechanism which implies...

Impact of previously disadvantaged land-users on sustainable ...

African Journals Online (AJOL)

Impact of previously disadvantaged land-users on sustainable agricultural ... about previously disadvantaged land users involved in communal farming systems ... of input, capital, marketing, information and land use planning, with effect on ...

Unappreciated epidemiology: the churn effect in a regional HIV care programme.

Science.gov (United States)

Gill, M J; Krentz, H B

2009-08-01

High levels of geographic mobility in and out of HIV care centres (i.e. the churn effect) can disrupt the continuity of patient care, misalign prevention services, impact local prevalence data perturbing optimal allocation of resources, and contribute to logical challenges in repeated transfer of health records. We report on the clinical, demographic, and administrative impact of high population turnover within HIV populations.

Determining root correspondence between previously and newly detected objects

Science.gov (United States)

Paglieroni, David W.; Beer, N Reginald

2014-06-17

A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.

Structured Mechanical Collage.

Science.gov (United States)

Huang, Zhe; Wang, Jiang; Fu, Hongbo; Lau, Rynson W H

2014-07-01

We present a method to build 3D structured mechanical collages consisting of numerous elements from the database given artist-designed proxy models. The construction is guided by some graphic design principles, namely unity, variety and contrast. Our results are visually more pleasing than previous works as confirmed by a user study.

Structure Formation Mechanisms during Solid Ti with Molten Al Interaction

International Nuclear Information System (INIS)

Gurevich, L; Pronichev, D; Trunov, M

2016-01-01

The study discuses advantages and disadvantages of previously proposed mechanisms of the formation of structure between solid Ti and molten Al and presents a new mechanism based on the reviewed and experimental data. The previously proposed mechanisms were classified into three groups: mechanisms of precipitation, mechanisms of destruction and mechanisms of chemical interaction between intermetallics and melt. The reviewed mechanisms did not explain the formation of heterogeneous interlayer with globular aluminide particles and thin layers of pure Al, while the present study reveals variation in the solid Ti/molten Al reaction kinetics during various phases of laminated metal-intermetallic composite formation. The proposed mechanism considers formed during composite fabrication thin oxide interlayers between Ti and Al evolution and its impact on the intermetallic compound formation and explains the initial slow rate of intermetallic interlayer formation and its subsequent acceleration when the oxide foils are ruptured. (paper)

Theoretical physics 2 analytical mechanics

CERN Document Server

Nolting, Wolfgang

2016-01-01

This textbook offers a clear and comprehensive introduction to analytical mechanics, one of the core components of undergraduate physics courses.It follows on naturally from the previous volumes in this series, thus expanding the knowledge in classical mechanics. The book starts with a thorough introduction into Lagrangian mechanics, detailing the d’Alembert principle, Hamilton’s principle and conservation laws. It continues with an in-depth explanation of Hamiltonian mechanics, illustrated by canonical and Legendre transformation, the generalization to quantum mechanics through Poisson brackets and all relevant variational principles. Finally, the Hamilton-Jacobi theory and the transition to wave mechanics are presented in detail. Ideally suited to undergraduate students with some grounding in classical mechanics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by ...

Mechanism of glucose electrochemical oxidation on gold surface

KAUST Repository

Pasta, Mauro; La Mantia, Fabio; Cui, Yi

2010-01-01

The complex oxidation of glucose at the surface of gold electrodes was studied in detail in different conditions of pH, buffer and halide concentration. As observed in previous studies, an oxidative current peak occurs during the cathodic sweep showing a highly linear dependence on glucose concentration, when other electrolyte conditions are unchanged. The effect of the different conditions on the intensity of this peak has stressed the limitations of the previously proposed mechanisms. A mechanism able to explain the presence of this oxidative peak was proposed. The mechanism takes into account ion-sorption and electrochemical adsorption of OH-, buffer species (K2HPO4/KH2PO4) and halides. © 2010 Elsevier Ltd. All rights reserved.

Mechanism of glucose electrochemical oxidation on gold surface

KAUST Repository

Pasta, Mauro

2010-08-01

The complex oxidation of glucose at the surface of gold electrodes was studied in detail in different conditions of pH, buffer and halide concentration. As observed in previous studies, an oxidative current peak occurs during the cathodic sweep showing a highly linear dependence on glucose concentration, when other electrolyte conditions are unchanged. The effect of the different conditions on the intensity of this peak has stressed the limitations of the previously proposed mechanisms. A mechanism able to explain the presence of this oxidative peak was proposed. The mechanism takes into account ion-sorption and electrochemical adsorption of OH-, buffer species (K2HPO4/KH2PO4) and halides. © 2010 Elsevier Ltd. All rights reserved.

A rare case of failed healing in previously burned skin after a secondary burns.

Science.gov (United States)

Goldie, Stephen J; Parsons, Shaun; Menezes, Hana; Ives, Andrew; Cleland, Heather

2017-01-01

Patients presenting with large surface area burns are common in our practice; however, patients with a secondary large burn on pre-existing burn scars and grafts are rare and not reported. We report on an unusual case of a patient sustaining a secondary large burn to areas previously injured by a burn from a different mechanism. We discuss the potential implications when managing a case like this and suggest potential biological reasons why the skin may behave differently. Our patient was a 33-year-old man who presented with a 5% TBSA burn on skin scarred by a previous 40% total body surface area (TBSA) burn and skin grafts. Initially assessed as superficial partial thickness in depth, the wounds were treated conservatively with dressings; however, they failed to heal and became infected requiring surgical management. Burns sustained in areas of previous burn scars and grafts may behave differently to normal patterns of healing, requiring more aggressive management and surgical intervention at an early stage.

Mechanical Biological Treatment

DEFF Research Database (Denmark)

Bilitewski, B-; Oros, Christiane; Christensen, Thomas Højlund

2011-01-01

The basic processes and technologies of composting and anaerobic digestion, as described in the previous chapters, are usually used for specific or source-separated organic waste flows. However, in the 1990s mechanical biological waste treatment technologies (MBT) were developed for unsorted...... or residual waste (after some recyclables removed at the source). The concept was originally to reduce the amount of waste going to landfill, but MBT technologies are today also seen as plants recovering fuel as well as material fractions. As the name suggests the technology combines mechanical treatment...... technologies (screens, sieves, magnets, etc.) with biological technologies (composting, anaerobic digestion). Two main technologies are available: Mechanical biological pretreatment (MBP), which first removes an RDF fraction and then biologically treats the remaining waste before most of it is landfilled...

Automatic electromagnetic valve for previous vacuum

International Nuclear Information System (INIS)

Granados, C. E.; Martin, F.

1959-01-01

A valve which permits the maintenance of an installation vacuum when electric current fails is described. It also lets the air in the previous vacuum bomb to prevent the oil ascending in the vacuum tubes. (Author)

Distinctive distribution of lymphocytes in unruptured and previously untreated brain arteriovenous malformation

Directory of Open Access Journals (Sweden)

Yi Guo

2014-12-01

Full Text Available Aim: To test the hypothesis that lymphocyte infiltration in brain arteriovenous malformation (bAVM is not associated with iron deposition (indicator of micro-hemorrhage. Methods: Sections of unruptured, previously untreated bAVM specimens (n = 19 were stained immunohistochemically for T-lymphocytes (CD3 + , B-lymphocytes (CD20 + , plasma cells (CD138 + and macrophages (CD68 + . Iron deposition was assessed by hematoxylin and eosin and Prussian blue stains. Superficial temporal arteries (STA were used as control. Results: Both T-lymphocytes and macrophages were present in unruptured, previously untreated bAVM specimens, whereas few B cells and plasma cells were detected. Iron deposition was detected in 8 specimens (42%; 95% confidence intervals = 20-67%. The samples with iron deposition tended to have more macrophages than those without (666 ± 313 vs. 478 ± 174 cells/mm 2 ; P = 0.11. T-cells were clustered on the luminal side of the endothelial surface, on the vessel-wall, and in the perivascular regions. There was no correlation between T-lymphocyte load and iron deposition (P = 0.88. No macrophages and lymphocytes were detected in STA controls. Conclusion: T-lymphocytes were present in bAVM specimens. Unlike macrophages, the load and location of T-lymphocytes were not associated with iron deposition, suggesting the possibility of an independent cell-mediated immunological mechanism in bAVM pathogenesis.

Clinical presentation of acute coronary syndrome in patients previously treated with nitrates.

Science.gov (United States)

Latour-Pérez, Jaime; Gómez-Tello, Vicente; Fuset-Cabanes, María Paz; Balsa, Eva de Miguel; Sáez, Frutos Del Nogal; Orts, Francisco Javier Coves; Rodríguez, Carmen Martín; Pino-Izquierdo, Karel; Pesquera, María de la Concepción Pavía; Rodríguez, Antonio José Montón

2013-11-01

Several reports have suggested that nitrates limit acute ischaemic damage by a mechanism similar to preconditioning. This study aims to evaluate the effect of chronic oral nitrates on the clinical presentation and short-term outcomes of patients admitted with acute coronary syndrome (ACS). A retrospective cohort study was conducted in patients with ACS admitted to 62 acute care units from 2010 to 2011. A propensity score-matched samples analysis was performed. We analysed 3171 consecutive patients, of whom 298 (9.4%) were chronically treated with nitrates. Patients previously treated with nitrates had higher comorbidity and disease severity at admission, lower prevalence of ACS with ST elevation, lower troponin elevation, higher prevalence of initial Killip class 2-4 and higher hospital mortality. The propensity score-matched analysis confirmed that previous use of nitrates is independently associated with a lower prevalence of ST-elevation ACS [odds ratio (OR) 0.53, 95% confidence interval (CI) 0.36-0.78; P = 0.0014] and a lower troponin elevation (OR 0.61, 95% CI 0.41-0.92) but not with Killip class on admission (OR 1.18, 95% CI 0.83-1.67, P = 0.3697) or mortality (OR 0.71, 95% CI 0.37-1.38, P = 0.3196). The results support the hypothesis that nitrates have a protective effect on acute ischaemic injury.

The discretized Schroedinger equation for the finite square well and its relationship to solid-state physics

International Nuclear Information System (INIS)

Boykin, Timothy B; Klimeck, Gerhard

2005-01-01

The discretized Schroedinger equation is most often used to solve one-dimensional quantum mechanics problems numerically. While it has been recognized for some time that this equation is equivalent to a simple tight-binding model and that the discretization imposes an underlying bandstructure unlike free-space quantum mechanics on the problem, the physical implications of this equivalence largely have been unappreciated and the pedagogical advantages accruing from presenting the problem as one of solid-state physics (and not numerics) remain generally unexplored. This is especially true for the analytically solvable discretized finite square well presented here. There are profound differences in the physics of this model and its continuous-space counterpart which are direct consequences of the imposed bandstructure. For example, in the discrete model the number of bound states plus transmission resonances equals the number of atoms in the quantum well

Transforming growth factor beta-activated kinase 1 (TAK1)-dependent checkpoint in the survival of dendritic cells promotes immune homeostasis and function.

Science.gov (United States)

Wang, Yanyan; Huang, Gonghua; Vogel, Peter; Neale, Geoffrey; Reizis, Boris; Chi, Hongbo

2012-02-07

Homeostatic control of dendritic cell (DC) survival is crucial for adaptive immunity, but the molecular mechanism is not well defined. Moreover, how DCs influence immune homeostasis under steady state remains unclear. Combining DC-specific and -inducible deletion systems, we report that transforming growth factor beta-activated kinase 1 (TAK1) is an essential regulator of DC survival and immune system homeostasis and function. Deficiency of TAK1 in CD11c(+) cells induced markedly elevated apoptosis, leading to the depletion of DC populations, especially the CD8(+) and CD103(+) DC subsets in lymphoid and nonlymphoid tissues, respectively. TAK1 also contributed to DC development by promoting the generation of DC precursors. Prosurvival signals from Toll-like receptors, CD40 and receptor activator of nuclear factor-κB (RANK) are integrated by TAK1 in DCs, which in turn mediated activation of downstream NF-κB and AKT-Foxo pathways and established a gene-expression program. TAK1 deficiency in DCs caused a myeloid proliferative disorder characterized by expansion of neutrophils and inflammatory monocytes, disrupted T-cell homeostasis, and prevented effective T-cell priming and generation of regulatory T cells. Moreover, TAK1 signaling in DCs was required to prevent myeloid proliferation even in the absence of lymphocytes, indicating a previously unappreciated regulatory mechanism of DC-mediated control of myeloid cell-dependent inflammation. Therefore, TAK1 orchestrates a prosurvival checkpoint in DCs that affects the homeostasis and function of the immune system.

Secondary recurrent miscarriage is associated with previous male birth.

LENUS (Irish Health Repository)

Ooi, Poh Veh

2012-01-31

Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53\\/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32\\/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78\\/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16\\/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19\\/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13\\/32 vs. 6\\/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.

Secondary recurrent miscarriage is associated with previous male birth.

LENUS (Irish Health Repository)

Ooi, Poh Veh

2011-01-01

Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53\\/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32\\/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78\\/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16\\/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19\\/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13\\/32 vs. 6\\/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.

Innate lymphoid cells in the initiation, regulation and resolution of inflammation

Science.gov (United States)

Sonnenberg, Gregory F.; Artis, David

2016-01-01

A previously unappreciated cell type of the innate immune system, termed innate lymphoid cells (ILCs), has been characterized in mice and humans, and found to profoundly influence the induction, regulation and resolution of inflammation. ILCs play an important role in these processes in murine models of infection, inflammatory disease and tissue repair. Further, disease association studies in defined patient populations have identified significant alterations in ILC responses, suggesting a potential role for these cell populations in human health and disease. In this review, we discuss the emerging family of ILCs, the role of ILCs in inflammation, and how current or novel therapeutic strategies could be employed to selectively modulate ILC responses and limit chronic inflammatory diseases in patients. PMID:26121198

Emergence of task-dependent representations in working memory circuits

Directory of Open Access Journals (Sweden)

Cristina eSavin

2014-05-01

Full Text Available A wealth of experimental evidence suggests that working memory circuits preferentially represent information that is behaviorally relevant. Still, we are missing a mechanistic account of how these representations come about. Here we provide a simple explanation for a range of experimental findings, in light of prefrontal circuits adapting to task constraints by reward-dependent learning. In particular, we model a neural network shaped by reward-modulated spike-timing dependent plasticity (r-STDP and homeostatic plasticity (intrinsic excitability and synaptic scaling. We show that the experimentally-observed neural representations naturally emerge in an initially unstructured circuit as it learns to solve several working memory tasks. These results point to a critical, and previously unappreciated, role for reward-dependent learning in shaping prefrontal cortex activity.

Classification and Regression Tree Analysis of Clinical Patterns that Predict Survival in 127 Chinese Patients with Advanced Non-small Cell Lung Cancer Treated by Gefitinib Who Failed to Previous Chemotherapy

Directory of Open Access Journals (Sweden)

Ziping WANG

2011-09-01

Full Text Available Background and objective It has been proven that gefitinib produces only 10%-20% tumor regression in heavily pretreated, unselected non-small cell lung cancer (NSCLC patients as the second- and third-line setting. Asian, female, nonsmokers and adenocarcinoma are favorable factors; however, it is difficult to find a patient satisfying all the above clinical characteristics. The aim of this study is to identify novel predicting factors, and to explore the interactions between clinical variables and their impact on the survival of Chinese patients with advanced NSCLC who were heavily treated with gefitinib in the second- or third-line setting. Methods The clinical and follow-up data of 127 advanced NSCLC patients referred to the Cancer Hospital & Institute, Chinese Academy of Medical Sciences from March 2005 to March 2010 were analyzed. Multivariate analysis of progression-free survival (PFS was performed using recursive partitioning, which is referred to as the classification and regression tree (CART analysis. Results The median PFS of 127 eligible consecutive advanced NSCLC patients was 8.0 months (95%CI: 5.8-10.2. CART was performed with an initial split on first-line chemotherapy outcomes and a second split on patients’ age. Three terminal subgroups were formed. The median PFS of the three subsets ranged from 1.0 month (95%CI: 0.8-1.2 for those with progressive disease outcome after the first-line chemotherapy subgroup, 10 months (95%CI: 7.0-13.0 in patients with a partial response or stable disease in first-line chemotherapy and age <70, and 22.0 months for patients obtaining a partial response or stable disease in first-line chemotherapy at age 70-81 (95%CI: 3.8-40.1. Conclusion Partial response, stable disease in first-line chemotherapy and age ≥ 70 are closely correlated with long-term survival treated by gefitinib as a second- or third-line setting in advanced NSCLC. CART can be used to identify previously unappreciated patient

Genomic interval engineering of mice identified a novel modulator of triglyceride production

Energy Technology Data Exchange (ETDEWEB)

Zhu, Y.; Jong, M.C.; Frazer, K.A.; Gong, E.; Krauss, R.M.; Cheng, J.F.; Boffelli, D.; Rubin, E.M.

1999-10-01

To accelerate the biological annotation of novel genes discovered in sequenced of mammalian genomes, we are creating large deletions in the mouse genome targeted to include clusters of such genes. Here we describe the targeted deletion of a 450 kb region on mouse chromosome 11 which, based on computational analysis of the deleted murine sequences and human 5q orthologous sequences, codes for nine putative genes. Mice homozygous for the deletion had a variety of abnormalities including severe hypertriglyceridemia, hepatic and cardiac enlargement, growth retardation and premature mortality. Analysis of triglyceride metabolism in these animals demonstrated a several-fold increase in hepatic very-low density lipoprotein (VLDL) triglyceride secretion, the most prevalent mechanism responsible for hypertriglyceridemia in humans. A series of mouse BAC and human YAC transgenes covering different intervals of the 450 kb deleted region were assessed for their ability to complement the deletion induced abnormalities. These studies revealed that OCTN2, a gene recently shown to play a role in carnitine transport, was able to correct the triglyceride abnormalities. The discovery of this previously unappreciated relationship between OCTN2, carnitine and hepatic triglyceride production is of particular importance due to the clinical consequence of hypertriglyceridemia and the paucity of genes known to modulate triglyceride secretion.

Complement-related proteins control the flavivirus infection of Aedes aegypti by inducing antimicrobial peptides.

Directory of Open Access Journals (Sweden)

Xiaoping Xiao

2014-04-01

Full Text Available The complement system functions during the early phase of infection and directly mediates pathogen elimination. The recent identification of complement-like factors in arthropods indicates that this system shares common ancestry in vertebrates and invertebrates as an immune defense mechanism. Thioester (TE-containing proteins (TEPs, which show high similarity to mammalian complement C3, are thought to play a key role in innate immunity in arthropods. Herein, we report that a viral recognition cascade composed of two complement-related proteins limits the flaviviral infection of Aedes aegypti. An A. aegypti macroglobulin complement-related factor (AaMCR, belonging to the insect TEP family, is a crucial effector in opposing the flaviviral infection of A. aegypti. However, AaMCR does not directly interact with DENV, and its antiviral effect requires an A. aegypti homologue of scavenger receptor-C (AaSR-C, which interacts with DENV and AaMCR simultaneously in vitro and in vivo. Furthermore, recognition of DENV by the AaSR-C/AaMCR axis regulates the expression of antimicrobial peptides (AMPs, which exerts potent anti-DENV activity. Our results both demonstrate the existence of a viral recognition pathway that controls the flaviviral infection by inducing AMPs and offer insights into a previously unappreciated antiviral function of the complement-like system in arthropods.

Reoperative sentinel lymph node biopsy after previous mastectomy.

Science.gov (United States)

Karam, Amer; Stempel, Michelle; Cody, Hiram S; Port, Elisa R

2008-10-01

Sentinel lymph node (SLN) biopsy is the standard of care for axillary staging in breast cancer, but many clinical scenarios questioning the validity of SLN biopsy remain. Here we describe our experience with reoperative-SLN (re-SLN) biopsy after previous mastectomy. Review of the SLN database from September 1996 to December 2007 yielded 20 procedures done in the setting of previous mastectomy. SLN biopsy was performed using radioisotope with or without blue dye injection superior to the mastectomy incision, in the skin flap in all patients. In 17 of 20 patients (85%), re-SLN biopsy was performed for local or regional recurrence after mastectomy. Re-SLN biopsy was successful in 13 of 20 patients (65%) after previous mastectomy. Of the 13 patients, 2 had positive re-SLN, and completion axillary dissection was performed, with 1 having additional positive nodes. In the 11 patients with negative re-SLN, 2 patients underwent completion axillary dissection demonstrating additional negative nodes. One patient with a negative re-SLN experienced chest wall recurrence combined with axillary recurrence 11 months after re-SLN biopsy. All others remained free of local or axillary recurrence. Re-SLN biopsy was unsuccessful in 7 of 20 patients (35%). In three of seven patients, axillary dissection was performed, yielding positive nodes in two of the three. The remaining four of seven patients all had previous modified radical mastectomy, so underwent no additional axillary surgery. In this small series, re-SLN was successful after previous mastectomy, and this procedure may play some role when axillary staging is warranted after mastectomy.

A quantum mechanics/molecular mechanics study on the hydrolysis mechanism of New Delhi metallo-β-lactamase-1.

Science.gov (United States)

Zhu, Kongkai; Lu, Junyan; Liang, Zhongjie; Kong, Xiangqian; Ye, Fei; Jin, Lu; Geng, Heji; Chen, Yong; Zheng, Mingyue; Jiang, Hualiang; Li, Jun-Qian; Luo, Cheng

2013-03-01

New Delhi metallo-β-lactamase-1 (NDM-1) has emerged as a major global threat to human health for its rapid rate of dissemination and ability to make pathogenic microbes resistant to almost all known β-lactam antibiotics. In addition, effective NDM-1 inhibitors have not been identified to date. In spite of the plethora of structural and kinetic data available, the accurate molecular characteristics of and details on the enzymatic reaction of NDM-1 hydrolyzing β-lactam antibiotics remain incompletely understood. In this study, a combined computational approach including molecular docking, molecular dynamics simulations and quantum mechanics/molecular mechanics calculations was performed to characterize the catalytic mechanism of meropenem catalyzed by NDM-1. The quantum mechanics/molecular mechanics results indicate that the ionized D124 is beneficial to the cleavage of the C-N bond within the β-lactam ring. Meanwhile, it is energetically favorable to form an intermediate if no water molecule coordinates to Zn2. Moreover, according to the molecular dynamics results, the conserved residue K211 plays a pivotal role in substrate binding and catalysis, which is quite consistent with previous mutagenesis data. Our study provides detailed insights into the catalytic mechanism of NDM-1 hydrolyzing meropenem β-lactam antibiotics and offers clues for the discovery of new antibiotics against NDM-1 positive strains in clinical studies.

77 FR 70176 - Previous Participation Certification

Science.gov (United States)

2012-11-23

... participants' previous participation in government programs and ensure that the past record is acceptable prior... information is designed to be 100 percent automated and digital submission of all data and certifications is... government programs and ensure that the past record is acceptable prior to granting approval to participate...

The whole-genome landscape of medulloblastoma subtypes

Science.gov (United States)

Northcott, Paul A.; Buchhalter, Ivo; Morrissy, A. Sorana; Hovestadt, Volker; Weischenfeldt, Joachim; Ehrenberger, Tobias; Groebner, Susanne; Segura-Wang, Maia; Zichner, Thomas; Rudneva, Vasilisa; Warnatz, Hans-Jörg; Sidiropoulos, Nikos; Phillips, Aaron H.; Schumacher, Steven; Kleinheinz, Kortine; Waszak, Sebastian M.; Erkek, Serap; Jones, David T.W.; Worst, Barbara C.; Kool, Marcel; Zapatka, Marc; Jäger, Natalie; Chavez, Lukas; Hutter, Barbara; Bieg, Matthias; Paramasivam, Nagarajan; Heinold, Michael; Gu, Zuguang; Ishaque, Naveed; Jäger-Schmidt, Christina; Imbusch, Charles D.; Jugold, Alke; Hübschmann, Daniel; Risch, Thomas; Amstislavskiy, Vyacheslav; Gonzalez, Francisco German Rodriguez; Weber, Ursula D.; Wolf, Stephan; Robinson, Giles W.; Zhou, Xin; Wu, Gang; Finkelstein, David; Liu, Yanling; Cavalli, Florence M.G.; Luu, Betty; Ramaswamy, Vijay; Wu, Xiaochong; Koster, Jan; Ryzhova, Marina; Cho, Yoon-Jae; Pomeroy, Scott L.; Herold-Mende, Christel; Schuhmann, Martin; Ebinger, Martin; Liau, Linda M.; Mora, Jaume; McLendon, Roger E.; Jabado, Nada; Kumabe, Toshihiro; Chuah, Eric; Ma, Yussanne; Moore, Richard A.; Mungall, Andrew J.; Mungall, Karen L.; Thiessen, Nina; Tse, Kane; Wong, Tina; Jones, Steven J.M.; Witt, Olaf; Milde, Till; Von Deimling, Andreas; Capper, David; Korshunov, Andrey; Yaspo, Marie-Laure; Kriwacki, Richard; Gajjar, Amar; Zhang, Jinghui; Beroukhim, Rameen; Fraenkel, Ernest; Korbel, Jan O.; Brors, Benedikt; Schlesner, Matthias; Eils, Roland; Marra, Marco A.; Pfister, Stefan M.; Taylor, Michael D.; Lichter, Peter

2018-01-01

Summary Current therapies for medulloblastoma (MB), a highly malignant childhood brain tumor, impose debilitating effects on the developing child, warranting deployment of molecularly targeted treatments with reduced toxicities. Prior studies failed to disclose the full spectrum of driver genes and molecular processes operative in MB subgroups. Herein, we detail the somatic landscape across 491 sequenced MBs and molecular heterogeneity amongst 1,256 epigenetically analyzed cases, identifying subgroup-specific driver alterations including previously unappreciated actionable targets. Driver mutations explained the majority of Group 3 and Group 4 patients, remarkably enhancing previous knowledge. Novel molecular subtypes were differentially enriched for specific driver events, including hotspot in-frame insertions targeting KBTBD4 and ‘enhancer hijacking’ driving PRDM6 activation. Thus, application of integrative genomics to an unprecedented cohort of clinical samples derived from a single childhood cancer entity disclosed a series of new cancer genes and biologically relevant subtype diversity that represent attractive therapeutic targets for treating MB patients. PMID:28726821

Fluid mechanics fundamentals and applications

CERN Document Server

Cengel, Yunus

2013-01-01

Cengel and Cimbala's Fluid Mechanics Fundamentals and Applications, communicates directly with tomorrow's engineers in a simple yet precise manner. The text covers the basic principles and equations of fluid mechanics in the context of numerous and diverse real-world engineering examples. The text helps students develop an intuitive understanding of fluid mechanics by emphasizing the physics, using figures, numerous photographs and visual aids to reinforce the physics. The highly visual approach enhances the learning of Fluid mechanics by students. This text distinguishes itself from others by the way the material is presented - in a progressive order from simple to more difficult, building each chapter upon foundations laid down in previous chapters. In this way, even the traditionally challenging aspects of fluid mechanics can be learned effectively. McGraw-Hill is also proud to offer ConnectPlus powered by Maple with the third edition of Cengel/Cimbabla, Fluid Mechanics. This innovative and powerful new sy...

[Prevalence of previously diagnosed diabetes mellitus in Mexico.

Science.gov (United States)

Rojas-Martínez, Rosalba; Basto-Abreu, Ana; Aguilar-Salinas, Carlos A; Zárate-Rojas, Emiliano; Villalpando, Salvador; Barrientos-Gutiérrez, Tonatiuh

2018-01-01

To compare the prevalence of previously diagnosed diabetes in 2016 with previous national surveys and to describe treatment and its complications. Mexico's national surveys Ensa 2000, Ensanut 2006, 2012 and 2016 were used. For 2016, logistic regression models and measures of central tendency and dispersion were obtained. The prevalence of previously diagnosed diabetes in 2016 was 9.4%. The increase of 2.2% relative to 2012 was not significant and only observed in patients older than 60 years. While preventive measures have increased, the access to medical treatment and lifestyle has not changed. The treatment has been modified, with an increase in insulin and decrease in hypoglycaemic agents. Population aging, lack of screening actions and the increase in diabetes complications will lead to an increase on the burden of disease. Policy measures targeting primary and secondary prevention of diabetes are crucial.

Mechanisms controlling the impact of multi-year drought on mountain hydrology.

Science.gov (United States)

Bales, Roger C; Goulden, Michael L; Hunsaker, Carolyn T; Conklin, Martha H; Hartsough, Peter C; O'Geen, Anthony T; Hopmans, Jan W; Safeeq, Mohammad

2018-01-12

Mountain runoff ultimately reflects the difference between precipitation (P) and evapotranspiration (ET), as modulated by biogeophysical mechanisms that intensify or alleviate drought impacts. These modulating mechanisms are seldom measured and not fully understood. The impact of the warm 2012-15 California drought on the heavily instrumented Kings River basin provides an extraordinary opportunity to enumerate four mechanisms that controlled the impact of drought on mountain hydrology. Two mechanisms intensified the impact: (i) evaporative processes have first access to local precipitation, which decreased the fractional allocation of P to runoff in 2012-15 and reduced P-ET by 30% relative to previous years, and (ii) 2012-15 was 1 °C warmer than the previous decade, which increased ET relative to previous years and reduced P-ET by 5%. The other two mechanisms alleviated the impact: (iii) spatial heterogeneity and the continuing supply of runoff from higher elevations increased 2012-15 P-ET by 10% relative to that expected for a homogenous basin, and iv) drought-associated dieback and wildfire thinned the forest and decreased ET, which increased 2016 P-ET by 15%. These mechanisms are all important and may offset each other; analyses that neglect one or more will over or underestimate the impact of drought and warming on mountain runoff.

Mechanics

CERN Document Server

Chester, W

1979-01-01

When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

75 FR 76056 - FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT:

Science.gov (United States)

2010-12-07

... SECURITIES AND EXCHANGE COMMISSION Sunshine Act Meeting FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT: STATUS: Closed meeting. PLACE: 100 F Street, NE., Washington, DC. DATE AND TIME OF PREVIOUSLY ANNOUNCED MEETING: Thursday, December 9, 2010 at 2 p.m. CHANGE IN THE MEETING: Time change. The closed...

Implant breast reconstruction after salvage mastectomy in previously irradiated patients.

Science.gov (United States)

Persichetti, Paolo; Cagli, Barbara; Simone, Pierfranco; Cogliandro, Annalisa; Fortunato, Lucio; Altomare, Vittorio; Trodella, Lucio

2009-04-01

The most common surgical approach in case of local tumor recurrence after quadrantectomy and radiotherapy is salvage mastectomy. Breast reconstruction is the subsequent phase of the treatment and the plastic surgeon has to operate on previously irradiated and manipulated tissues. The medical literature highlights that breast reconstruction with tissue expanders is not a pursuable option, considering previous radiotherapy a contraindication. The purpose of this retrospective study is to evaluate the influence of previous radiotherapy on 2-stage breast reconstruction (tissue expander/implant). Only patients with analogous timing of radiation therapy and the same demolitive and reconstructive procedures were recruited. The results of this study prove that, after salvage mastectomy in previously irradiated patients, implant reconstruction is still possible. Further comparative studies are, of course, advisable to draw any conclusion on the possibility to perform implant reconstruction in previously irradiated patients.

28 CFR 10.5 - Incorporation of papers previously filed.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Incorporation of papers previously filed... CARRYING ON ACTIVITIES WITHIN THE UNITED STATES Registration Statement § 10.5 Incorporation of papers previously filed. Papers and documents already filed with the Attorney General pursuant to the said act and...

No discrimination against previous mates in a sexually cannibalistic spider

Science.gov (United States)

Fromhage, Lutz; Schneider, Jutta M.

2005-09-01

In several animal species, females discriminate against previous mates in subsequent mating decisions, increasing the potential for multiple paternity. In spiders, female choice may take the form of selective sexual cannibalism, which has been shown to bias paternity in favor of particular males. If cannibalistic attacks function to restrict a male's paternity, females may have little interest to remate with males having survived such an attack. We therefore studied the possibility of female discrimination against previous mates in sexually cannibalistic Argiope bruennichi, where females almost always attack their mate at the onset of copulation. We compared mating latency and copulation duration of males having experienced a previous copulation either with the same or with a different female, but found no evidence for discrimination against previous mates. However, males copulated significantly shorter when inserting into a used, compared to a previously unused, genital pore of the female.

Subsequent childbirth after a previous traumatic birth.

Science.gov (United States)

Beck, Cheryl Tatano; Watson, Sue

2010-01-01

Nine percent of new mothers in the United States who participated in the Listening to Mothers II Postpartum Survey screened positive for meeting the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for posttraumatic stress disorder after childbirth. Women who have had a traumatic birth experience report fewer subsequent children and a longer length of time before their second baby. Childbirth-related posttraumatic stress disorder impacts couples' physical relationship, communication, conflict, emotions, and bonding with their children. The purpose of this study was to describe the meaning of women's experiences of a subsequent childbirth after a previous traumatic birth. Phenomenology was the research design used. An international sample of 35 women participated in this Internet study. Women were asked, "Please describe in as much detail as you can remember your subsequent pregnancy, labor, and delivery following your previous traumatic birth." Colaizzi's phenomenological data analysis approach was used to analyze the stories of the 35 women. Data analysis yielded four themes: (a) riding the turbulent wave of panic during pregnancy; (b) strategizing: attempts to reclaim their body and complete the journey to motherhood; (c) bringing reverence to the birthing process and empowering women; and (d) still elusive: the longed-for healing birth experience. Subsequent childbirth after a previous birth trauma has the potential to either heal or retraumatize women. During pregnancy, women need permission and encouragement to grieve their prior traumatic births to help remove the burden of their invisible pain.

Mechanics from Newton's laws to deterministic chaos

CERN Document Server

Scheck, Florian

2018-01-01

This book covers all topics in mechanics from elementary Newtonian mechanics, the principles of canonical mechanics and rigid body mechanics to relativistic mechanics and nonlinear dynamics. It was among the first textbooks to include dynamical systems and deterministic chaos in due detail. As compared to the previous editions the present 6th edition is updated and revised with more explanations, additional examples and problems with solutions, together with new sections on applications in science.   Symmetries and invariance principles, the basic geometric aspects of mechanics as well as elements of continuum mechanics also play an important role. The book will enable the reader to develop general principles from which equations of motion follow, to understand the importance of canonical mechanics and of symmetries as a basis for quantum mechanics, and to get practice in using general theoretical concepts and tools that are essential for all branches of physics.   The book contains more than 150 problems ...

Novel "Elements" of Immune Suppression within the Tumor Microenvironment.

Science.gov (United States)

Gurusamy, Devikala; Clever, David; Eil, Robert; Restifo, Nicholas P

2017-06-01

Adaptive evolution has prompted immune cells to use a wide variety of inhibitory signals, many of which are usurped by tumor cells to evade immune surveillance. Although tumor immunologists often focus on genes and proteins as mediators of immune function, here we highlight two elements from the periodic table-oxygen and potassium-that suppress the immune system in previously unappreciated ways. While both are key to the maintenance of T-cell function and tissue homeostasis, they are exploited by tumors to suppress immuno-surveillance and promote metastatic spread. We discuss the temporal and spatial roles of these elements within the tumor microenvironment and explore possible therapeutic interventions for effective and promising anticancer therapies. Cancer Immunol Res; 5(6); 426-33. ©2017 AACR . ©2017 American Association for Cancer Research.

Development and Validation of Chemical Kinetic Mechanism Reduction Scheme for Large-Scale Mechanisms

DEFF Research Database (Denmark)

Poon, Hiew Mun; Ng, Hoon Kiat; Gan, Suyin

2014-01-01

This work is an extension to a previously reported work on chemical kinetic mechanism reduction scheme for large-scale mechanisms. Here, Perfectly Stirred Reactor (PSR) was added as a criterion of data source for mechanism reduction instead of using only auto-ignition condition. As a result......) simulations were performed to study the spray combustion phenomena within a constant volume bomb. Both non-reacting and reacting conditions were applied in this study. Liquid and vapor penetration lengths were replicated for non-reacting diesel spray. For reacting diesel spray, both ignition delay and lift......-off length were simulated. The simulation results were then compared to the experimental data of Sandia National Laboratories and No. 2 Diesel Fuel (D2) was designated as the reference fuel. Both liquid and vapor penetrations for non-reacting condition were well-matched, while ignition delay was advanced...

Price volatility in wind dominant electricity markets

DEFF Research Database (Denmark)

Farashbashi-Astaneh, Seyed-Mostafa; Chen, Zhe

2013-01-01

High penetration of intermittent renewable energy sources causes price volatility in future electricity markets. This is specially the case in European countries that plan high penetration levels. This highlights the necessity for revising market regulations and mechanisms in accordance...... to generation combination portfolio. Proposed solutions should be able to tackle with emerging challenges which are mainly due to high variability and unpredictability of intermittent renewable resources. In this paper high price volatility will be introduced as an emerging challenge in wind dominant...... electricity markets. High price volatility is unappreciated because it imposes high financial risk levels to both electricity consumers and producers. Additionally high price variations impede tracking price signals by consumers in future smart grid and jeopardize implementation of demand response concepts...

Transmission of the gut microbiota: spreading of health

Science.gov (United States)

Browne, Hilary P.; Neville, B. Anne; Forster, Samuel C.; Lawley, Trevor D.

2018-01-01

Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria. PMID:28603278

ER stress stimulates production of the key antimicrobial peptide, cathelicidin, by forming a previously unidentified intracellular S1P signaling complex.

Science.gov (United States)

Park, Kyungho; Ikushiro, Hiroko; Seo, Ho Seong; Shin, Kyong-Oh; Kim, Young Il; Kim, Jong Youl; Lee, Yong-Moon; Yano, Takato; Holleran, Walter M; Elias, Peter; Uchida, Yoshikazu

2016-03-08

We recently identified a previously unidentified sphingosine-1-phosphate (S1P) signaling mechanism that stimulates production of a key innate immune element, cathelicidin antimicrobial peptide (CAMP), in mammalian cells exposed to external perturbations, such as UVB irradiation and other oxidative stressors that provoke subapoptotic levels of endoplasmic reticulum (ER) stress, independent of the well-known vitamin D receptor-dependent mechanism. ER stress increases cellular ceramide and one of its distal metabolites, S1P, which activates NF-κB followed by C/EBPα activation, leading to CAMP production, but in a S1P receptor-independent fashion. We now show that S1P activates NF-κB through formation of a previously unidentified signaling complex, consisting of S1P, TRAF2, and RIP1 that further associates with three stress-responsive proteins; i.e., heat shock proteins (GRP94 and HSP90α) and IRE1α. S1P specifically interacts with the N-terminal domain of heat shock proteins. Because this ER stress-initiated mechanism is operative in both epithelial cells and macrophages, it appears to be a universal, highly conserved response, broadly protective against diverse external perturbations that lead to increased ER stress. Finally, these studies further illuminate how ER stress and S1P orchestrate critical stress-specific signals that regulate production of one protective response by stimulating production of the key innate immune element, CAMP.

Previously unidentified changes in renal cell carcinoma gene expression identified by parametric analysis of microarray data

International Nuclear Information System (INIS)

Lenburg, Marc E; Liou, Louis S; Gerry, Norman P; Frampton, Garrett M; Cohen, Herbert T; Christman, Michael F

2003-01-01

Renal cell carcinoma is a common malignancy that often presents as a metastatic-disease for which there are no effective treatments. To gain insights into the mechanism of renal cell carcinogenesis, a number of genome-wide expression profiling studies have been performed. Surprisingly, there is very poor agreement among these studies as to which genes are differentially regulated. To better understand this lack of agreement we profiled renal cell tumor gene expression using genome-wide microarrays (45,000 probe sets) and compare our analysis to previous microarray studies. We hybridized total RNA isolated from renal cell tumors and adjacent normal tissue to Affymetrix U133A and U133B arrays. We removed samples with technical defects and removed probesets that failed to exhibit sequence-specific hybridization in any of the samples. We detected differential gene expression in the resulting dataset with parametric methods and identified keywords that are overrepresented in the differentially expressed genes with the Fisher-exact test. We identify 1,234 genes that are more than three-fold changed in renal tumors by t-test, 800 of which have not been previously reported to be altered in renal cell tumors. Of the only 37 genes that have been identified as being differentially expressed in three or more of five previous microarray studies of renal tumor gene expression, our analysis finds 33 of these genes (89%). A key to the sensitivity and power of our analysis is filtering out defective samples and genes that are not reliably detected. The widespread use of sample-wise voting schemes for detecting differential expression that do not control for false positives likely account for the poor overlap among previous studies. Among the many genes we identified using parametric methods that were not previously reported as being differentially expressed in renal cell tumors are several oncogenes and tumor suppressor genes that likely play important roles in renal cell

Previously unknown species of Aspergillus.

Science.gov (United States)

Gautier, M; Normand, A-C; Ranque, S

2016-08-01

The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care. Copyright © 2016 European Society of Clinical Microbiology and

78 FR 13057 - Agency Information Collection Activities; Information Collection; IT Dashboard Feedback Mechanism

Science.gov (United States)

2013-02-26

... Information Collection Activities; Information Collection; IT Dashboard Feedback Mechanism AGENCY: Office of... previously approved information collection requirement regarding IT Dashboard Feedback Mechanism. DATES... Collection 3090- 0285, IT Dashboard Feedback Mechanism, by any of the following methods: Regulations.gov...

The dark personality and psychopathology : Toward a brighter future

NARCIS (Netherlands)

Thomaes, Sander; Brummelman, Eddie; Miller, Joshua D; Lilienfeld, Scott O

2017-01-01

The young field of research on dark personality traits (i.e., socially aversive traits such as psychopathy, narcissism, and Machiavellianism) is gaining momentum. This Special Section examines the nature, origins, development, and sequelae of dark traits, underscoring their largely unappreciated

Specialist bees collect Asteraceae pollen by distinctive abdominal drumming (Osmia) or tapping (Melissodes, Svastra)

Science.gov (United States)

Four species of western US Osmia (Cephalosmia) bees that are Asteraceae specialists (oligoleges) were observed to employ a heretofore unappreciated, stereotypical means of collecting pollen, abdominal drumming, to gather pollen from 19 flowering species representing nine tribes of Asteraceae. Abdom...

22 CFR 40.93 - Aliens unlawfully present after previous immigration violation.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens unlawfully present after previous... TO BOTH NONIMMIGRANTS AND IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.93 Aliens unlawfully present after previous immigration violation. An alien described...

Creep deformation mechanisms in a γ titanium aluminide

Energy Technology Data Exchange (ETDEWEB)

Abdallah, Zakaria [Institute of Structural Materials, College of Engineering, Bay Campus, Swansea University, Swansea SA18EN (United Kingdom); Ding, Rengen [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B152TT (United Kingdom); Martin, Nigel; Dixon, Mark [Rolls-Royce plc, P.O. Box 31, Derby DE248BJ (United Kingdom); Bache, Martin [Institute of Structural Materials, College of Engineering, Bay Campus, Swansea University, Swansea SA18EN (United Kingdom)

2016-09-15

Titanium aluminides (TiAl) are considered as potential alternatives to replace nickel-based alloys of greater density for selected components within future gas turbine aero-engines. This is attributed to the high specific strength as well as the good oxidation resistance at elevated temperatures. The gamma (γ) titanium aluminide system Ti-45Al-2Mn-2Nb has previously demonstrated promising performance in terms of its physical and mechanical properties. The main aim of the current study, which is a continuation of a previously published paper, aims at evaluating the performance of this titanium aluminide system under high temperature creep conditions. Of particular interest, the paper is strongly demonstrating the precise capability of the Wilshire Equations technique in predicting the long-term creep behaviour of this alloy. Moreover, it presents a physically meaningful understanding of the various creep mechanisms expected under various testing conditions. To achieve this, two creep specimens, tested under distinctly different stress levels at 700 °C have been extensively examined. Detailed microstructural investigations and supporting transmission electron microscopy (TEM) have explored the differences in creep mechanisms active under the two stress regimes, with the deformation mechanisms correlated to Wilshire creep life prediction curves.

Numerical modelling of self healing mechanisms

NARCIS (Netherlands)

Remmers, J.J.C.; Borst, de R.; Zwaag, van der S.

2007-01-01

A number of self healing mechanisms for composite materials have been presented in the previous chapters of this book. These methods vary from the classical concept of micro-encapsulating of healing agents in polymer systems to the autonomous healing of concrete. The key feature of these self

Mechanical thrombectomy in basilar artery thrombosis

DEFF Research Database (Denmark)

Fesl, Gunther; Holtmannspoetter, Markus; Patzig, Maximilian

2014-01-01

PURPOSE: Multiple endovascular devices have been used for mechanical thrombectomy (MT) in basilar artery occlusion (BAO) for >10 years. Based on a single-center experience during the course of one decade, we present data on safety and efficacy of previous MT devices compared with modern stent...

New mechanism of spiral wave initiation in a reaction-diffusion-mechanics system.

Science.gov (United States)

Weise, Louis D; Panfilov, Alexander V

2011-01-01

Spiral wave initiation in the heart muscle is a mechanism for the onset of dangerous cardiac arrhythmias. A standard protocol for spiral wave initiation is the application of a stimulus in the refractory tail of a propagating excitation wave, a region that we call the "classical vulnerable zone." Previous studies of vulnerability to spiral wave initiation did not take the influence of deformation into account, which has been shown to have a substantial effect on the excitation process of cardiomyocytes via the mechano-electrical feedback phenomenon. In this work we study the effect of deformation on the vulnerability of excitable media in a discrete reaction-diffusion-mechanics (dRDM) model. The dRDM model combines FitzHugh-Nagumo type equations for cardiac excitation with a discrete mechanical description of a finite-elastic isotropic material (Seth material) to model cardiac excitation-contraction coupling and stretch activated depolarizing current. We show that deformation alters the "classical," and forms a new vulnerable zone at longer coupling intervals. This mechanically caused vulnerable zone results in a new mechanism of spiral wave initiation, where unidirectional conduction block and rotation directions of the consequently initiated spiral waves are opposite compared to the mechanism of spiral wave initiation due to the "classical vulnerable zone." We show that this new mechanism of spiral wave initiation can naturally occur in situations that involve wave fronts with curvature, and discuss its relation to supernormal excitability of cardiac tissue. The concept of mechanically induced vulnerability may lead to a better understanding about the onset of dangerous heart arrhythmias via mechano-electrical feedback.

Fracture mechanics model of fragmentation

International Nuclear Information System (INIS)

Glenn, L.A.; Gommerstadt, B.Y.; Chudnovsky, A.

1986-01-01

A model of the fragmentation process is developed, based on the theory of linear elastic fracture mechanics, which predicts the average fragment size as a function of strain rate and material properties. This approach permits a unification of previous results, yielding Griffith's solution in the low-strain-rate limit and Grady's solution at high strain rates

18 CFR 154.302 - Previously submitted material.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Previously submitted material. 154.302 Section 154.302 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY... concurrently with the rate change filing. There must be furnished to the Director, Office of Energy Market...

Subsequent pregnancy outcome after previous foetal death

NARCIS (Netherlands)

Nijkamp, J. W.; Korteweg, F. J.; Holm, J. P.; Timmer, A.; Erwich, J. J. H. M.; van Pampus, M. G.

Objective: A history of foetal death is a risk factor for complications and foetal death in subsequent pregnancies as most previous risk factors remain present and an underlying cause of death may recur. The purpose of this study was to evaluate subsequent pregnancy outcome after foetal death and to

The mechanical spectra of deposited materials by a composite reed vibration method

International Nuclear Information System (INIS)

Ying, X.N.; Zhang, L.; Yuan, Y.H.

2010-01-01

Recently a composite reed vibration method has been designed to measure the mechanical spectra (complex Young's modulus) of materials from liquid to solid state. The mechanical spectra of materials can be obtained from a composite system consisting of a substrate reed and of materials deposited on it. In this report, two sets of formulas to calculate the mechanical spectra of deposited materials are further analyzed. The proof is given for the previous named 'approximate formulas' (labeled as Formula II). Then the composite reed vibration method can be safely used as an extension of the mechanical spectrum method of the thin solid film. At the same time, some comments are made on previous analytical formulas (labeled as Formula I). At last, more experiments with a small amount of deposited materials are performed. It is found that smaller quantity is more favorable to achieve the intrinsic mechanical spectra of deposited materials.

Theoretical physics 1 classical mechanics

CERN Document Server

Nolting, Wolfgang

2016-01-01

This textbook offers a clear and comprehensive introduction to classical mechanics, one of the core components of undergraduate physics courses. The book starts with a thorough introduction to the mathematical tools needed, to make this textbook self-contained for learning. The second part of the book introduces the mechanics of the free mass point and details conservation principles. The third part expands the previous to mechanics of many particle systems. Finally the mechanics of the rigid body is illustrated with rotational forces, inertia and gyroscope movement. Ideally suited to undergraduate students in their first year, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series...

Hilbert space and quantum mechanics

CERN Document Server

Gallone, Franco

2015-01-01

The topics of this book are the mathematical foundations of non-relativistic quantum mechanics and the mathematical theory they require. The main characteristic of the book is that the mathematics is developed assuming familiarity with elementary analysis only. Moreover, all the proofs are carried out in detail. These features make the book easily accessible to readers with only the mathematical training offered by undergraduate education in mathematics or in physics, and also ideal for individual study. The principles of quantum mechanics are discussed with complete mathematical accuracy and an effort is made to always trace them back to the experimental reality that lies at their root. The treatment of quantum mechanics is axiomatic, with definitions followed by propositions proved in a mathematical fashion. No previous knowledge of quantum mechanics is required. This book is designed so that parts of it can be easily used for various courses in mathematics and mathematical physics, as suggested in the Pref...

Ontogeny, morphology and mechanics of the tessellated skeleton of cartilaginous fishes

Science.gov (United States)

Dean, Mason N.

2009-12-01

The members of the successful and diverse lineage of elasmobranch fishes (sharks, rays and relatives) possess endoskeletons fashioned entirely of cartilage. This is counterintuitive because cartilage, unlike bone, lacks a major blood supply and has limited capacity for repair; yet these fishes exhibit particularly dynamic lifestyles and high levels of performance. The functionality of this skeletal tissue is likely due to its mineralization: in most skeletal elements, the soft cartilage core is tiled (tessellated) with an outer rind of abutting hydroxyapatite blocks called tesserae, joined together by intertesseral fibers and overlain by the fibrous perichondrium. This basic composite arrangement of tissues has been appreciated for over a century, but available techniques have limited the ability to examine elasmobranch cartilage adequately---without artifacts, in 3-dimensions and at high resolution---so that its development, mechanics and phylogeny might be contextualized among vertebrate skeletal tissues. I summarize the history, nomenclature and challenges relating to study of tessellated cartilage (Chapter 1) and present a low temperature microscopy technique to facilitate visualization of all tissue components in situ (Chapter 2). I use that technique in tandem with synchrotron microtomography to examine the ultrastructure of tesserae (Chapter 3) and the development of tessellated cartilage across ontogeny (Chapter 4). Finally, I examine the ways in which selection acts on skeletal morphology by examining cranial anatomy across 40 species of batoid fishes (rays and relatives) in the contexts of ecology and phylogeny (Chapter 5). There are some similarities between mineralizing bone and elasmobranch cartilage (e.g. the flattening of peripheral cells in the unmineralized phase, decreases in cellular density with mineralization, the presence of canaliculi connecting entombed cells). However, the ability for tessellated cartilage to grow (through enlargement of

Left ventricular asynergy score as an indicator of previous myocardial infarction

International Nuclear Information System (INIS)

Backman, C.; Jacobsson, K.A.; Linderholm, H.; Osterman, G.

1986-01-01

Sixty-eight patients with coronary heart disease (CHD) i.e. a hisotry of angina of effort and/or previous 'possible infarction' were examined inter alia with ECG and cinecardioangiography. A system of scoring was designed which allowed a semiquantitative estimate of the left ventricular asynergy from cinecardioangiography - the left ventricular motion score (LVMS). The LVMS was associated with the presence of a previous myocardial infarction (MI), as indicated by the history and ECG findings. The ECG changes specific for a previous MI were associated with high LVMS values and unspecific or absent ECG changes with low LVMS values. Decision thresholds for ECG changes and asynergy in diagnosing a previous MI were evaluated by means of a ROC analysis. The accuracy of ECG in detecting a previous MI was slightly higher when asynergy indicated a 'true MI' than when autopsy result did so in a comparable group. Therefore the accuracy of asynergy (LVMS ≥ 1) in detecting a previous MI or myocardial fibrosis in patients with CHD should be at least comparable with that of autopsy (scar > 1 cm). (orig.)

Topological fluid mechanics of Axisymmetric Flow

DEFF Research Database (Denmark)

Brøns, Morten

1998-01-01

Topological fluid mechanics in the sense of the present paper is the study and classification of flow patterns close to a critical point. Here we discuss the topology of steady viscous incompressible axisymmetric flows in the vicinity of the axis. Following previous studies the velocity field v...... to the authors knowledge has not been used systematically to high orders in topological fluid mechanics. We compare the general results with experimental and computational results on the Vogel-Ronneberg flow. We show that the topology changes observed when recirculating bubbles on the vortex axis are created...

Quantum Mechanics/Molecular Mechanics Simulations Identify the Ring-Opening Mechanism of Creatininase.

Science.gov (United States)

Jitonnom, Jitrayut; Mujika, Jon I; van der Kamp, Marc W; Mulholland, Adrian J

2017-12-05

Creatininase catalyzes the conversion of creatinine (a biosensor for kidney function) to creatine via a two-step mechanism: water addition followed by ring opening. Water addition is common to other known cyclic amidohydrolases, but the precise mechanism for ring opening is still under debate. The proton donor in this step is either His178 or a water molecule bound to one of the metal ions, and the roles of His178 and Glu122 are unclear. Here, the two possible reaction pathways have been fully examined by means of combined quantum mechanics/molecular mechanics simulations at the SCC-DFTB/CHARMM22 level of theory. The results indicate that His178 is the main catalytic residue for the whole reaction and explain its role as proton shuttle during the ring-opening step. In the first step, His178 provides electrostatic stabilization to the gem-diolate tetrahedral intermediate. In the second step, His178 abstracts the hydroxyl proton of the intermediate and delivers it to the cyclic amide nitrogen, leading to ring opening. The latter is the rate-limiting step with a free energy barrier of 18.5 kcal/mol, in agreement with the experiment. We find that Glu122 must be protonated during the enzyme reaction, so that it can form a stable hydrogen bond with its neighboring water molecule. Simulations of the E122Q mutant showed that this replacement disrupts the H-bond network formed by three conserved residues (Glu34, Ser78, and Glu122) and water, increasing the energy barrier. Our computational studies provide a comprehensive explanation for previous structural and kinetic observations, including why the H178A mutation causes a complete loss of activity but the E122Q mutation does not.

Classical to quantum mechanical tunneling mechanism crossover in thermal transitions between magnetic states.

Science.gov (United States)

Vlasov, Sergei; Bessarab, Pavel F; Uzdin, Valery M; Jónsson, Hannes

2016-12-22

Transitions between states of a magnetic system can occur by jumps over an energy barrier or by quantum mechanical tunneling through the energy barrier. The rate of such transitions is an important consideration when the stability of magnetic states is assessed for example for nanoscale candidates for data storage devices. The shift in transition mechanism from jumps to tunneling as the temperature is lowered is analyzed and a general expression derived for the crossover temperature. The jump rate is evaluated using a harmonic approximation to transition state theory. First, the minimum energy path for the transition is found with the geodesic nudged elastic band method. The activation energy for the jumps is obtained from the maximum along the path, a saddle point on the energy surface, and the eigenvalues of the Hessian matrix at that point as well as at the initial state minimum used to estimate the entropic pre-exponential factor. The crossover temperature for quantum mechanical tunneling is evaluated from the second derivatives of the energy with respect to orientation of the spin vector at the saddle point. The resulting expression is applied to test problems where analytical results have previously been derived, namely uniaxial and biaxial spin systems with two-fold anisotropy. The effect of adding four-fold anisotropy on the crossover temperature is demonstrated. Calculations of the jump rate and crossover temperature for tunneling are also made for a molecular magnet containing an Mn 4 group. The results are in excellent agreement with previously reported experimental measurements on this system.

Reasoning with Previous Decisions: Beyond the Doctrine of Precedent

DEFF Research Database (Denmark)

Komárek, Jan

2013-01-01

in different jurisdictions use previous judicial decisions in their argument, we need to move beyond the concept of precedent to a wider notion, which would embrace practices and theories in legal systems outside the Common law tradition. This article presents the concept of ‘reasoning with previous decisions...... law method’, but they are no less rational and intellectually sophisticated. The reason for the rather conceited attitude of some comparatists is in the dominance of the common law paradigm of precedent and the accompanying ‘case law method’. If we want to understand how courts and lawyers......’ as such an alternative and develops its basic models. The article first points out several shortcomings inherent in limiting the inquiry into reasoning with previous decisions by the common law paradigm (1). On the basis of numerous examples provided in section (1), I will present two basic models of reasoning...

On the Tengiz petroleum deposit previous study

International Nuclear Information System (INIS)

Nysangaliev, A.N.; Kuspangaliev, T.K.

1997-01-01

Tengiz petroleum deposit previous study is described. Some consideration about structure of productive formation, specific characteristic properties of petroleum-bearing collectors are presented. Recommendation on their detail study and using of experience on exploration and development of petroleum deposit which have analogy on most important geological and industrial parameters are given. (author)

On certain two-dimensional conservative mechanical systems with a cubic second integral

CERN Document Server

Yehia, H M

2002-01-01

In a previous paper (Yehia H M 1986 J. Mec. Theor. Appl. 5 55-71) we have introduced a method for constructing integrable conservative two-dimensional mechanical systems whose second integral of motion is polynomial in the velocities. This method has proved successful in constructing a multitude of irreversible systems (involving gyroscopic forces) with a second quadratic integral (Yehia H M 1992 J. Phys. A: Math. Gen. 25 197-221). The objective of this paper is to apply the same method for the systematic construction of mechanical systems with a cubic integral. As in our previous works, the configuration space is not assumed to be a Euclidean plane. This widens the range of applicability of the results to diverse mechanical systems to include such problems as rigid body dynamics. Several new reversible and irreversible integrable systems are obtained. Some of these systems generalize previously known ones by introducing additional parameters which may change either or both of the configuration manifold and t...

Left thoracotomy HeartWare implantation with outflow graft anastomosis to the descending aorta: a simplified bridge for patients with multiple previous sternotomies.

Science.gov (United States)

Umakanthan, Ramanan; Haglund, Nicholas A; Stulak, John M; Joyce, Lyle D; Ahmad, Rashid; Keebler, Mary E; Maltais, Simon

2013-01-01

Advances in mechanical circulatory support have been critical in bridging patients awaiting heart transplantation. In addition, improvement in device durability has enabled left ventricular assist device therapy to be applied as destination therapy in those not felt to be transplant candidate. Because of the increasing complexity of patients, there continues to be a need for alternative strategies for device implantation to bridge high-risk patients awaiting heart transplantation, wherein the risks of numerous previous sternotomies may be prohibitive. We present a unique technique for placement of the HeartWare ventricular assist device via left anterior thoracotomy to the descending aorta in a patient awaiting heart transplantation with a history of multiple previous sternotomies.

New mechanism of spiral wave initiation in a reaction-diffusion-mechanics system.

Directory of Open Access Journals (Sweden)

Louis D Weise

Full Text Available Spiral wave initiation in the heart muscle is a mechanism for the onset of dangerous cardiac arrhythmias. A standard protocol for spiral wave initiation is the application of a stimulus in the refractory tail of a propagating excitation wave, a region that we call the "classical vulnerable zone." Previous studies of vulnerability to spiral wave initiation did not take the influence of deformation into account, which has been shown to have a substantial effect on the excitation process of cardiomyocytes via the mechano-electrical feedback phenomenon. In this work we study the effect of deformation on the vulnerability of excitable media in a discrete reaction-diffusion-mechanics (dRDM model. The dRDM model combines FitzHugh-Nagumo type equations for cardiac excitation with a discrete mechanical description of a finite-elastic isotropic material (Seth material to model cardiac excitation-contraction coupling and stretch activated depolarizing current. We show that deformation alters the "classical," and forms a new vulnerable zone at longer coupling intervals. This mechanically caused vulnerable zone results in a new mechanism of spiral wave initiation, where unidirectional conduction block and rotation directions of the consequently initiated spiral waves are opposite compared to the mechanism of spiral wave initiation due to the "classical vulnerable zone." We show that this new mechanism of spiral wave initiation can naturally occur in situations that involve wave fronts with curvature, and discuss its relation to supernormal excitability of cardiac tissue. The concept of mechanically induced vulnerability may lead to a better understanding about the onset of dangerous heart arrhythmias via mechano-electrical feedback.

Quantifying the mechanisms of domain gain in animal proteins.

Science.gov (United States)

Buljan, Marija; Frankish, Adam; Bateman, Alex

2010-01-01

Protein domains are protein regions that are shared among different proteins and are frequently functionally and structurally independent from the rest of the protein. Novel domain combinations have a major role in evolutionary innovation. However, the relative contributions of the different molecular mechanisms that underlie domain gains in animals are still unknown. By using animal gene phylogenies we were able to identify a set of high confidence domain gain events and by looking at their coding DNA investigate the causative mechanisms. Here we show that the major mechanism for gains of new domains in metazoan proteins is likely to be gene fusion through joining of exons from adjacent genes, possibly mediated by non-allelic homologous recombination. Retroposition and insertion of exons into ancestral introns through intronic recombination are, in contrast to previous expectations, only minor contributors to domain gains and have accounted for less than 1% and 10% of high confidence domain gain events, respectively. Additionally, exonization of previously non-coding regions appears to be an important mechanism for addition of disordered segments to proteins. We observe that gene duplication has preceded domain gain in at least 80% of the gain events. The interplay of gene duplication and domain gain demonstrates an important mechanism for fast neofunctionalization of genes.

Generalized Poisson processes in quantum mechanics and field theory

International Nuclear Information System (INIS)

Combe, P.; Rodriguez, R.; Centre National de la Recherche Scientifique, 13 - Marseille; Hoegh-Krohn, R.; Centre National de la Recherche Scientifique, 13 - Marseille; Sirugue, M.; Sirugue-Collin, M.; Centre National de la Recherche Scientifique, 13 - Marseille

1981-01-01

In section 2 we describe more carefully the generalized Poisson processes, giving a realization of the underlying probability space, and we characterize these processes by their characteristic functionals. Section 3 is devoted to the proof of the previous formula for quantum mechanical systems, with possibly velocity dependent potentials and in section 4 we give an application of the previous theory to some relativistic Bose field models. (orig.)

Nuclear Magnetic Shielding Constants from Quantum Mechanical/Molecular Mechanical Calculations Using Polarizable Embedding: Role of the Embedding Potential

DEFF Research Database (Denmark)

Steinmann, Casper; Olsen, Jógvan Magnus Haugaard; Kongsted, Jacob

2014-01-01

We present NMR shielding constants obtained through quantum mechanical/molecular mechanical (QM/MM) embedding calculations. Contrary to previous reports, we show that a relatively small QM region is sufficient, provided that a high-quality embedding potential is used. The calculated averaged NMR...... shielding constants of both acrolein and acetone solvated in water are based on a number of snapshots extracted from classical molecular dynamics simulations. We focus on the carbonyl chromophore in both molecules, which shows large solvation effects, and we study the convergence of shielding constants...

A linear chromatic mechanism drives the pupillary response.

Science.gov (United States)

Tsujimura, S.; Wolffsohn, J. S.; Gilmartin, B.

2001-01-01

Previous studies have shown that a chromatic mechanism can drive pupil responses. The aim of this research was to clarify whether a linear or nonlinear chromatic mechanism drives pupillary responses by using test stimuli of various colours that are defined in cone contrast space. The pupil and accommodation responses evoked by these test stimuli were continuously and simultaneously objectively measured by photorefraction. The results with isochromatic and isoluminant stimuli showed that the accommodative level remained approximately constant (< 0.25 D change in mean level) even when the concurrent pupillary response was large (ca. 0.30 mm). The pupillary response to an isoluminant grating was sustained, delayed (by ca. 60 ms) and larger in amplitude than that for a isochromatic uniform stimulus, which supports previous work suggesting that the chromatic mechanism contributes to the pupillary response. In a second experiment, selected chromatic test gratings were used and isoresponse contours in cone contrast space were obtained. The results showed that the isoresponse contour in cone contrast space is well described (r(2) = 0.99) by a straight line with a positive slope. The results indicate that a /L - M/ linear chromatic mechanism, whereby a signal from the long wavelength cone is subtracted from that of the middle wavelength cone and vice versa, drives pupillary responses. PMID:11674867

Should previous mammograms be digitised in the transition to digital mammography?

International Nuclear Information System (INIS)

Taylor-Phillips, S.; Gale, A.G.; Wallis, M.G.

2009-01-01

Breast screening specificity is improved if previous mammograms are available, which presents a challenge when converting to digital mammography. Two display options were investigated: mounting previous film mammograms on a multiviewer adjacent to the workstation, or digitising them for soft copy display. Eight qualified screen readers were videotaped undertaking routine screen reading for two 45-min sessions in each scenario. Analysis of gross eye and head movements showed that when digitised, previous mammograms were examined a greater number of times per case (p=0.03), due to a combination of being used in 19% more cases (p=0.04) and where used, looked at a greater number of times (28% increase, p=0.04). Digitising previous mammograms reduced both the average time taken per case by 18% (p=0.04) and the participants' perceptions of workload (p < 0.05). Digitising previous analogue mammograms may be advantageous, in particular in increasing their level of use. (orig.)

Concise Review : Adult Salivary Gland Stem Cells and a Potential Therapy for Xerostomia

NARCIS (Netherlands)

Pringle, Sarah; Van Os, Ronald; Coppes, Robert P.

The ability to speak, swallow, masticate, taste food, and maintain a healthy oral cavity is heavily reliant on the presence of saliva, the hugely important effect of which on our everyday lives is often unappreciated. Hyposalivation, frequently experienced by people receiving radiation therapy for

14 CFR 121.406 - Credit for previous CRM/DRM training.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Credit for previous CRM/DRM training. 121... previous CRM/DRM training. (a) For flightcrew members, the Administrator may credit CRM training received before March 19, 1998 toward all or part of the initial ground CRM training required by § 121.419. (b...

Challenging previous conceptions of vegetarianism and eating disorders.

Science.gov (United States)

Fisak, B; Peterson, R D; Tantleff-Dunn, S; Molnar, J M

2006-12-01

The purpose of this study was to replicate and expand upon previous research that has examined the potential association between vegetarianism and disordered eating. Limitations of previous research studies are addressed, including possible low reliability of measures of eating pathology within vegetarian samples, use of only a few dietary restraint measures, and a paucity of research examining potential differences in body image and food choice motives of vegetarians versus nonvegetarians. Two hundred and fifty-six college students completed a number of measures of eating pathology and body image, and a food choice motives questionnaire. Interestingly, no significant differences were found between vegetarians and nonvegetarians in measures of eating pathology or body image. However, significant differences in food choice motives were found. Implications for both researchers and clinicians are discussed.

A Direct Mechanism of Ultrafast Intramolecular Singlet Fission in Pentacene Dimers

Science.gov (United States)

2016-08-24

Queisser limit of solar power conversion efficiency. In conventional materials, the mechanism of SF is an intermolecular process (xSF), which is mediated by...property for materials used in third-generation solar cells and photodetectors, among other optoelectronic devices.1−3 Unfortunately, techno- logical...mixing. Previous work investigating the mechanism of xSF unfavorably compared the direct coupling mechanism against superexchange mediated by high

Maximum mass-particle velocities in Kantor's information mechanics

International Nuclear Information System (INIS)

Sverdlik, D.I.

1989-01-01

Kantor's information mechanics links phenomena previously regarded as not treatable by a single theory. It is used here to calculate the maximum velocities υ m of single particles. For the electron, υ m /c ∼ 1 - 1.253814 x 10 -77 . The maximum υ m corresponds to υ m /c ∼ 1 -1.097864 x 10 -122 for a single mass particle with a rest mass of 3.078496 x 10 -5 g. This is the fastest that matter can move. Either information mechanics or classical mechanics can be used to show that υ m is less for heavier particles. That υ m is less for lighter particles can be deduced from an information mechanics argument alone

Quantitative phosphoproteomics dissection of 7TM receptor signaling using full and biased agonists

DEFF Research Database (Denmark)

Christensen, Gitte L; Kelstrup, Christian D; Lyngsø, Christina

2010-01-01

only activates the Gaq protein-independent signaling.e quantified more than ten thousand phosphorylation sites of which 1183 were regulated by Angiotensin II or its analogue SII Angiotensin II. 36% of the AT1R regulated phosphorylations were regulated by SII Angiotensin II. Analysis of phosphorylation...... into Angiotensin II signal transduction and is the first study dissecting the differences between a full agonist and a biased agonist from a 7TMR on a systems-wide scale. Importantly, it reveals a previously unappreciated diversity and quantity of Gaq protein-independent signaling and uncovers novel signaling......Seven-transmembrane receptors (7TMRs) signal through the well described heterotrimeric G proteins, but can also activate G protein-independent signaling pathways of which the impact and complexity are less understood. The Angiotensin II type 1 receptor (AT1R) is a prototypical 7TMR and an important...

Opposing Actions of Fgf8a on Notch Signaling Distinguish Two Muller Glial Cell Populations that Contribute to Retina Growth and Regeneration

Directory of Open Access Journals (Sweden)

Jin Wan

2017-04-01

Full Text Available The teleost retina grows throughout life and exhibits a robust regenerative response following injury. Critical to both these events are Muller glia (or, Muller glial cells; MGs, which produce progenitors for retinal growth and repair. We report that Fgf8a may be an MG niche factor that acts through Notch signaling to regulate spontaneous and injury-dependent MG proliferation. Remarkably, forced Fgf8a expression inhibits Notch signaling and stimulates MG proliferation in young tissue but increases Notch signaling and suppresses MG proliferation in older tissue. Furthermore, cessation of Fgf8a signaling enhances MG proliferation in both young and old retinal tissue. Our study suggests that multiple MG populations contribute to retinal growth and regeneration, and it reveals a previously unappreciated role for Fgf8a and Notch signaling in regulating MG quiescence, activation, and proliferation.

Distinct Spatiotemporal Dynamics of Peptidoglycan Synthesis between Mycobacterium smegmatis and Mycobacterium tuberculosis

Directory of Open Access Journals (Sweden)

Helene Botella

2017-09-01

Full Text Available Peptidoglycan (PG, a polymer cross-linked by d-amino acid-containing peptides, is an essential component of the bacterial cell wall. We found that a fluorescent d-alanine analog (FDAA incorporates chiefly at one of the two poles in Mycobacterium smegmatis but that polar dominance varies as a function of the cell cycle in Mycobacterium tuberculosis: immediately after cytokinesis, FDAAs are incorporated chiefly at one of the two poles, but just before cytokinesis, FDAAs are incorporated comparably at both. These observations suggest that mycobacterial PG-synthesizing enzymes are localized in functional compartments at the poles and septum and that the capacity for PG synthesis matures at the new pole in M. tuberculosis. Deeper knowledge of the biology of mycobacterial PG synthesis may help in discovering drugs that disable previously unappreciated steps in the process.

Atherosclerotic Plaque Destabilization Mechanisms, Models, and Therapeutic Strategies

NARCIS (Netherlands)

Silvestre-Roig, Carlos; de Winther, Menno P.; Weber, Christian; Daemen, Mat J.; Lutgens, Esther; Soehnlein, Oliver

2014-01-01

Understanding the pathophysiology of atherogenesis and the progression of atherosclerosis have been major goals of cardiovascular research during the previous decades. However, the complex molecular and cellular mechanisms underlying plaque destabilization remain largely obscure. Here, we review how

Quantum mechanical determination of atomic polarizabilities of ionic liquids.

Science.gov (United States)

Heid, Esther; Szabadi, András; Schröder, Christian

2018-04-25

The distribution of a molecule's polarizability to individual atomic sites is inevitable to develop accurate polarizable force fields. We present the direct quantum mechanical calculation of atomic polarizabilities of 27 common ionic liquids. The method is superior to previously published distribution routines based on large databases of the molecular polarizability, and enables the correct description of any ionic liquid and its peculiarities within the quantum mechanical framework.

Response to health insurance by previously uninsured rural children.

Science.gov (United States)

Tilford, J M; Robbins, J M; Shema, S J; Farmer, F L

1999-08-01

To examine the healthcare utilization and costs of previously uninsured rural children. Four years of claims data from a school-based health insurance program located in the Mississippi Delta. All children who were not Medicaid-eligible or were uninsured, were eligible for limited benefits under the program. The 1987 National Medical Expenditure Survey (NMES) was used to compare utilization of services. The study represents a natural experiment in the provision of insurance benefits to a previously uninsured population. Premiums for the claims cost were set with little or no information on expected use of services. Claims from the insurer were used to form a panel data set. Mixed model logistic and linear regressions were estimated to determine the response to insurance for several categories of health services. The use of services increased over time and approached the level of utilization in the NMES. Conditional medical expenditures also increased over time. Actuarial estimates of claims cost greatly exceeded actual claims cost. The provision of a limited medical, dental, and optical benefit package cost approximately $20-$24 per member per month in claims paid. An important uncertainty in providing health insurance to previously uninsured populations is whether a pent-up demand exists for health services. Evidence of a pent-up demand for medical services was not supported in this study of rural school-age children. States considering partnerships with private insurers to implement the State Children's Health Insurance Program could lower premium costs by assembling basic data on previously uninsured children.

Abiraterone in metastatic prostate cancer without previous chemotherapy

NARCIS (Netherlands)

Ryan, Charles J.; Smith, Matthew R.; de Bono, Johann S.; Molina, Arturo; Logothetis, Christopher J.; de Souza, Paul; Fizazi, Karim; Mainwaring, Paul; Piulats, Josep M.; Ng, Siobhan; Carles, Joan; Mulders, Peter F. A.; Basch, Ethan; Small, Eric J.; Saad, Fred; Schrijvers, Dirk; van Poppel, Hendrik; Mukherjee, Som D.; Suttmann, Henrik; Gerritsen, Winald R.; Flaig, Thomas W.; George, Daniel J.; Yu, Evan Y.; Efstathiou, Eleni; Pantuck, Allan; Winquist, Eric; Higano, Celestia S.; Taplin, Mary-Ellen; Park, Youn; Kheoh, Thian; Griffin, Thomas; Scher, Howard I.; Rathkopf, Dana E.; Boyce, A.; Costello, A.; Davis, I.; Ganju, V.; Horvath, L.; Lynch, R.; Marx, G.; Parnis, F.; Shapiro, J.; Singhal, N.; Slancar, M.; van Hazel, G.; Wong, S.; Yip, D.; Carpentier, P.; Luyten, D.; de Reijke, T.

2013-01-01

Abiraterone acetate, an androgen biosynthesis inhibitor, improves overall survival in patients with metastatic castration-resistant prostate cancer after chemotherapy. We evaluated this agent in patients who had not received previous chemotherapy. In this double-blind study, we randomly assigned

The HETE Is on FFAR1 and Pancreatic Islet Cells

DEFF Research Database (Denmark)

Trauelsen, Mette; Lückmann, Michael; Frimurer, Thomas M

2018-01-01

It is known but generally unappreciated that the fatty acid receptor FFAR1 (GPR40) is responsible for a major part of glucose-induced insulin secretion. This puzzling fact is now explained by Tunaru et al. (2018), who demonstrate that glucose-induced 20-hydroxyeicosatetraenoic acid (20-HETE...

Squamous cell carcinoma arising in previously burned or irradiated skin

International Nuclear Information System (INIS)

Edwards, M.J.; Hirsch, R.M.; Broadwater, J.R.; Netscher, D.T.; Ames, F.C.

1989-01-01

Squamous cell carcinoma (SCC) arising in previously burned or irradiated skin was reviewed in 66 patients treated between 1944 and 1986. Healing of the initial injury was complicated in 70% of patients. Mean interval from initial injury to diagnosis of SCC was 37 years. The overwhelming majority of patients presented with a chronic intractable ulcer in previously injured skin. The regional relapse rate after surgical excision was very high, 58% of all patients. Predominant patterns of recurrence were in local skin and regional lymph nodes (93% of recurrences). Survival rates at 5, 10, and 20 years were 52%, 34%, and 23%, respectively. Five-year survival rates in previously burned and irradiated patients were not significantly different (53% and 50%, respectively). This review, one of the largest reported series, better defines SCC arising in previously burned or irradiated skin as a locally aggressive disease that is distinct from SCC arising in sunlight-damaged skin. An increased awareness of the significance of chronic ulceration in scar tissue may allow earlier diagnosis. Regional disease control and survival depend on surgical resection of all known disease and may require radical lymph node dissection or amputation

Characterization of porosity in support of mechanical property analysis

International Nuclear Information System (INIS)

Price, R.H.; Martin, R.J. III; Boyd, P.J.

1992-01-01

Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sample tested. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characterizing the internal structure of the sample prior to testing is being developed and the results are being analyzed. The information obtained from this technique can help in both qualitative and quantitative interpretation of test results

Horizon quantum mechanics of rotating black holes

Energy Technology Data Exchange (ETDEWEB)

Casadio, Roberto [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Giugno, Andrea [Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Giusti, Andrea [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Micu, Octavian [Institute of Space Science, Bucharest, P.O. Box MG-23, Bucharest-Magurele (Romania)

2017-05-15

The horizon quantum mechanics is an approach that was previously introduced in order to analyze the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. In this work, we first extend the formalism to general space-times with asymptotic (ADM) mass and angular momentum. We then apply the extended horizon quantum mechanics to a harmonic model of rotating corpuscular black holes. We find that simple configurations of this model naturally suppress the appearance of the inner horizon and seem to disfavor extremal (macroscopic) geometries. (orig.)

Structure and mechanical properties of Octopus vulgaris suckers.

Science.gov (United States)

Tramacere, Francesca; Kovalev, Alexander; Kleinteich, Thomas; Gorb, Stanislav N; Mazzolai, Barbara

2014-02-06

In this study, we investigate the morphology and mechanical features of Octopus vulgaris suckers, which may serve as a model for the creation of a new generation of attachment devices. Octopus suckers attach to a wide range of substrates in wet conditions, including rough surfaces. This amazing feature is made possible by the sucker's tissues, which are pliable to the substrate profile. Previous studies have described a peculiar internal structure that plays a fundamental role in the attachment and detachment processes of the sucker. In this work, we present a mechanical characterization of the tissues involved in the attachment process, which was performed using microindentation tests. We evaluated the elasticity modulus and viscoelastic parameters of the natural tissues (E ∼ 10 kPa) and measured the mechanical properties of some artificial materials that have previously been used in soft robotics. Such a comparison of biological prototypes and artificial material that mimics octopus-sucker tissue is crucial for the design of innovative artificial suction cups for use in wet environments. We conclude that the properties of the common elastomers that are generally used in soft robotics are quite dissimilar to the properties of biological suckers.

Cardiovascular magnetic resonance in adults with previous cardiovascular surgery.

Science.gov (United States)

von Knobelsdorff-Brenkenhoff, Florian; Trauzeddel, Ralf Felix; Schulz-Menger, Jeanette

2014-03-01

Cardiovascular magnetic resonance (CMR) is a versatile non-invasive imaging modality that serves a broad spectrum of indications in clinical cardiology and has proven evidence. Most of the numerous applications are appropriate in patients with previous cardiovascular surgery in the same manner as in non-surgical subjects. However, some specifics have to be considered. This review article is intended to provide information about the application of CMR in adults with previous cardiovascular surgery. In particular, the two main scenarios, i.e. following coronary artery bypass surgery and following heart valve surgery, are highlighted. Furthermore, several pictorial descriptions of other potential indications for CMR after cardiovascular surgery are given.

Computing pKa Values with a Mixing Hamiltonian Quantum Mechanical/Molecular Mechanical Approach.

Science.gov (United States)

Liu, Yang; Fan, Xiaoli; Jin, Yingdi; Hu, Xiangqian; Hu, Hao

2013-09-10

Accurate computation of the pKa value of a compound in solution is important but challenging. Here, a new mixing quantum mechanical/molecular mechanical (QM/MM) Hamiltonian method is developed to simulate the free-energy change associated with the protonation/deprotonation processes in solution. The mixing Hamiltonian method is designed for efficient quantum mechanical free-energy simulations by alchemically varying the nuclear potential, i.e., the nuclear charge of the transforming nucleus. In pKa calculation, the charge on the proton is varied in fraction between 0 and 1, corresponding to the fully deprotonated and protonated states, respectively. Inspired by the mixing potential QM/MM free energy simulation method developed previously [H. Hu and W. T. Yang, J. Chem. Phys. 2005, 123, 041102], this method succeeds many advantages of a large class of λ-coupled free-energy simulation methods and the linear combination of atomic potential approach. Theory and technique details of this method, along with the calculation results of the pKa of methanol and methanethiol molecules in aqueous solution, are reported. The results show satisfactory agreement with the experimental data.

Dynamic Matching Markets and the Deferred Acceptance Mechanism

DEFF Research Database (Denmark)

Kennes, John; Monte, Daniel; Tumennasan, Norovsambuu

In many dynamic matching markets, priorities depend on previous allocations. In such environments, agents on the proposing side can manipulate the period-by-period deferred acceptance (DA) mechanism. We show that the fraction of agents with incentives to manipulate the DA mechanism approaches zero...... as the market size increases. In addition, we provide a novel al- gorithm to calculate the percentage of markets that can be manipulated. Based on randomly generated data, we find that the DA becomes approximately non-manipulable when the schools capacity reaches 20. Our theoretical and simulation results...... together justify the implementation of the period-by-period DA mechanism in dynamic markets....

Political Socialization.

Science.gov (United States)

Himmelweit, Hilde T.

1983-01-01

Described are two longitudinal studies, one British, the other American, which examined the influences of varied socializing agents--e.g., family, school, peer groups--on voting behavior. The studies emphasized the hitherto unappreciated importance of the political, social, and economic climate of society and its changes on socialization. (CS)

Birds of a Feather: Applied Behavior Analysis and Quality of Life

Science.gov (United States)

Gambrill, Eileen

2013-01-01

Applied behavior analysts have been helping people to enhance the quality of their lives for decades. Its characteristics as described by Baer, Wolf, and Risley continue to guide efforts to help clients and their significant others. Yet, this knowledge often languishes unused and unappreciated. Distortions and misrepresentations of applied…

Molecular Mechanisms of Bacterial Pathogenicity

Science.gov (United States)

Fuchs, Thilo Martin

Cautious optimism has arisen over recent decades with respect to the long struggle against bacteria, viruses, and parasites. This has been offset, however, by a fatal complacency stemming from previous successes such as the development of antimicrobial drugs, the eradication of smallpox, and global immunization programs. Infectious diseases nevertheless remain the world's leading cause of death, killing at least 17 million persons annually [61]. Diarrheal diseases caused by Vibrio cholerae or Shigella dysenteriae kill about 3 million persons every year, most of them young children: Another 4 million die of tuberculosis or tetanus. Outbreaks of diphtheria in Eastern Europe threatens the population with a disease that had previously seemed to be overcome. Efforts to control infectious diseases more comprehensively are undermined not only by socioeconomic conditions but also by the nature of the pathogenic organisms itself; some isolates of Staphylococcus aureus and Enterobacter have become so resistant to drugs by horizontal gene transfer that they are almost untreatable. In addition, the mechanism of genetic variability helps pathogens to evade the human immune system, thus compromising the development of powerful vaccines. Therefore detailed knowledge of the molecular mechanisms of microbial pathogenicity is absolutely necessary to develop new strategies against infectious diseases and thus to lower their impact on human health and social development.

Previously unreported abnormalities in Wolfram Syndrome Type 2.

Science.gov (United States)

Akturk, Halis Kaan; Yasa, Seda

2017-01-01

Wolfram syndrome (WFS) is a rare autosomal recessive disease with non-autoimmune childhood onset insulin dependent diabetes and optic atrophy. WFS type 2 (WFS2) differs from WFS type 1 (WFS1) with upper intestinal ulcers, bleeding tendency and the lack ofdiabetes insipidus. Li-fespan is short due to related comorbidities. Only a few familieshave been reported with this syndrome with the CISD2 mutation. Here we report two siblings with a clinical diagnosis of WFS2, previously misdiagnosed with type 1 diabetes mellitus and diabetic retinopathy-related blindness. We report possible additional clinical and laboratory findings that have not been pre-viously reported, such as asymptomatic hypoparathyroidism, osteomalacia, growth hormone (GH) deficiency and hepatomegaly. Even though not a requirement for the diagnosis of WFS2 currently, our case series confirm hypogonadotropic hypogonadism to be also a feature of this syndrome, as reported before. © Polish Society for Pediatric Endocrinology and Diabetology.

Five criteria for using a surrogate endpoint to predict treatment effect based on data from multiple previous trials.

Science.gov (United States)

Baker, Stuart G

2018-02-20

A surrogate endpoint in a randomized clinical trial is an endpoint that occurs after randomization and before the true, clinically meaningful, endpoint that yields conclusions about the effect of treatment on true endpoint. A surrogate endpoint can accelerate the evaluation of new treatments but at the risk of misleading conclusions. Therefore, criteria are needed for deciding whether to use a surrogate endpoint in a new trial. For the meta-analytic setting of multiple previous trials, each with the same pair of surrogate and true endpoints, this article formulates 5 criteria for using a surrogate endpoint in a new trial to predict the effect of treatment on the true endpoint in the new trial. The first 2 criteria, which are easily computed from a zero-intercept linear random effects model, involve statistical considerations: an acceptable sample size multiplier and an acceptable prediction separation score. The remaining 3 criteria involve clinical and biological considerations: similarity of biological mechanisms of treatments between the new trial and previous trials, similarity of secondary treatments following the surrogate endpoint between the new trial and previous trials, and a negligible risk of harmful side effects arising after the observation of the surrogate endpoint in the new trial. These 5 criteria constitute an appropriately high bar for using a surrogate endpoint to make a definitive treatment recommendation. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Multiple bilateral lower limb fractures in a 2-year-old child: previously unreported injury with a unique mechanism

Directory of Open Access Journals (Sweden)

Anuj Jain

2014-10-01

Full Text Available 【Abstract】Fall from height is a common cause of unintentional injuries in children and accounts for 6% of all trauma-related childhood deaths, usually from head injury. We report a case of a 2-year-old child with multiple fractures of the bilateral lower limbs due to this reason. A child fell from a height of around 15 feet after toppling from a alcony. He developed multiple fractures involving the right femoral shaft, right distal femoral epiphysis (Salter Harris type 2, right distal metaphysis of the tibia and fi bula, and undisplaced Salter Harris type 2 epiphyseal injury of the left distal tibia. There were no head, abdominal or spinal injuries. The patient was taken into emergency operation theatre after initial management which consisted of intravenous fl uids, blood transfusion, and splintage of both lower limbs. Fracture of the femoral shaft was treated by closed reduction and fixation using two titanium elastic nails. Distal femoral physeal injury required open eduction and fixation with K wires. Distal tibia fractures were closely reduced and managed nonoperatively in both the lower limbs. All the fractures united in four weeks. At the last follow-up, the child had no disability and was able to perform daily ctivities comfortably. We also proposed the unique mechanism of injury in this report. Key words: Multiple bilateral lower limb fractures; Fall; Child

Outcome Of Pregnancy Following A Previous Lower Segment ...

African Journals Online (AJOL)

Background: A previous ceasarean section is an important variable that influences patient management in subsequent pregnancies. A trial of vaginal delivery in such patients is a feasible alternative to a secondary section, thus aiding to reduce the ceasarean section rate and its associated co-morbidities. Objective: To ...

Cryptococcal meningitis in a previously healthy child | Chimowa ...

African Journals Online (AJOL)

An 8-year-old previously healthy female presented with a 3 weeks history of headache, neck stiffness, deafness, fever and vomiting and was diagnosed with cryptococcal meningitis. She had documented hearing loss and was referred to tertiary-level care after treatment with fluconazole did not improve her neurological ...

24 CFR 1710.552 - Previously accepted state filings.

Science.gov (United States)

2010-04-01

... of Substantially Equivalent State Law § 1710.552 Previously accepted state filings. (a) Materials... and contracts or agreements contain notice of purchaser's revocation rights. In addition see § 1715.15..., unless the developer is obligated to do so in the contract. (b) If any such filing becomes inactive or...

Sudden unexpected death in children with a previously diagnosed cardiovascular disorder

NARCIS (Netherlands)

Polderman, Florens N.; Cohen, Joeri; Blom, Nico A.; Delhaas, Tammo; Helbing, Wim A.; Lam, Jan; Sobotka-Plojhar, Marta A.; Temmerman, Arno M.; Sreeram, Narayanswani

2004-01-01

BACKGROUND: It is known that children with previously diagnosed heart defects die suddenly. The causes of death are often unknown. OBJECTIVE: The aim of the study was to identify all infants and children within the Netherlands with previously diagnosed heart disease who had a sudden unexpected death

Sudden unexpected death in children with a previously diagnosed cardiovascular disorder

NARCIS (Netherlands)

Polderman, F.N.; Cohen, Joeri; Blom, N.A.; Delhaas, T.; Helbing, W.A.; Lam, J.; Sobotka-Plojhar, M.A.; Temmerman, Arno M.; Sreeram, N.

2004-01-01

Background: It is known that children with previously diagnosed heart defects die suddenly. The causes of death are often unknown. Objective: The aim of the study was to identify all infants and children within the Netherlands with previously diagnosed heart disease who had a sudden unexpected death

Influence of mechanical and thermal treatments on microstructure and mechanical properties of titanium stabilized austenitic stainless steels

International Nuclear Information System (INIS)

Sidhom, H.

1983-12-01

Thermal and mechanical treatments for microstructure optimization in titanium stabilized austenitic stainless steels used in nuclear industry are examined. The steels studied Z10CNDT15-15B and Z6CNDT17-13 are of the type 15-15 Ti and 316 Ti. These treatments allow the elimination of casting heterogeneity produced by dendritic solidification, improve mechanical properties particularly creep and the best compromise between grain size solid solution of metal additions is obtained. Secondary precipitation of (TiMo)C on dislocations is improved by a previous strain hardening. The precipitation reinforce the good effect of strain hardening by stabilization of the microstructure producing a better resistance to recrystallization [fr

75 FR 20933 - Airworthiness Directives; Arrow Falcon Exporters, Inc. (previously Utah State University...

Science.gov (United States)

2010-04-22

... Hawkins and Powers Aviation, Inc.); S.M.&T. Aircraft (previously US Helicopters, Inc., UNC Helicopter, Inc... Joaquin Helicopters (previously Hawkins and Powers Aviation, Inc.); S.M.&T. Aircraft (previously US...

40 CFR 152.93 - Citation of a previously submitted valid study.

Science.gov (United States)

2010-07-01

... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may demonstrate compliance for a data requirement by citing a valid study previously submitted to the Agency. The... the original data submitter, the applicant may cite the study only in accordance with paragraphs (b...

Investigation of previously derived Hyades, Coma, and M67 reddenings

International Nuclear Information System (INIS)

Taylor, B.J.

1980-01-01

New Hyades polarimetry and field star photometry have been obtained to check the Hyades reddening, which was found to be nonzero in a previous paper. The new Hyades polarimetry implies essentially zero reddening; this is also true of polarimetry published by Behr (which was incorrectly interpreted in the previous paper). Four photometric techniques which are presumed to be insensitive to blanketing are used to compare the Hyades to nearby field stars; these four techniques also yield essentially zero reddening. When all of these results are combined with others which the author has previously published and a simultaneous solution for the Hyades, Coma, and M67 reddenings is made, the results are E (B-V) =3 +- 2 (sigma) mmag, -1 +- 3 (sigma) mmag, and 46 +- 6 (sigma) mmag, respectively. No support for a nonzero Hyades reddening is offered by the new results. When the newly obtained reddenings for the Hyades, Coma, and M67 are compared with results from techniques given by Crawford and by users of the David Dunlap Observatory photometric system, no differences between the new and other reddenings are found which are larger than about 2 sigma. The author had previously found that the M67 main-sequence stars have about the same blanketing as that of Coma and less blanketing than the Hyades; this conclusion is essentially unchanged by the revised reddenings

Process cells dismantling of EUREX pant: previous activities

International Nuclear Information System (INIS)

Gili, M.

1998-01-01

In the '98-'99 period some process cells of the EUREX pant will be dismantled, in order to place there the liquid wastes conditioning plant 'CORA'. This report resumes the previous activities (plant rinsing campaigns and inactive Cell 014 dismantling), run in the past three years and the drawn experience [it

75 FR 39143 - Airworthiness Directives; Arrow Falcon Exporters, Inc. (previously Utah State University); AST...

Science.gov (United States)

2010-07-08

... (previously Precision Helicopters, LLC); Robinson Air Crane, Inc.; San Joaquin Helicopters (previously Hawkins... (Previously Hawkins & Powers Aviation); S.M. &T. Aircraft (Previously Us Helicopter Inc., UNC Helicopters, Inc...

Auction Mechanism of Micro-Grid Project Transfer

Directory of Open Access Journals (Sweden)

Yong Long

2017-10-01

Full Text Available Micro-grid project transfer is the primary issue of micro-grid development. The efficiency and quality of the micro-grid project transfer directly affect the quality of micro-grid project construction and development, which is very important for the sustainable development of micro-grid. This paper constructs a multi-attribute auction model of micro-grid project transfer, which reflects the characteristics of micro-grid system and the interests of stakeholders, calculates the optimal bidding strategy and analyzes the influence of relevant factors on auction equilibrium by multi-stage dynamic game with complete information, and makes a numerical simulation analysis. Results indicate that the optimal strategy of auction mechanism is positively related to power quality, energy storage quality, and carbon emissions. Different from the previous lowest price winning mechanism, the auction mechanism formed in this paper emphasizes that the energy suppliers which provide the comprehensive optimization of power quality, energy storage quality, carbon emissions, and price will win the auction, when both the project owners and energy suppliers maximize their benefits under this auction mechanism. The auction mechanism is effective because it is in line with the principle of individual rationality and incentive compatibility. In addition, the number of energy suppliers participating in the auction and the cost of the previous auction are positively related to the auction equilibrium, both of which are adjusting the equilibrium results of the auction. At the same time, the utilization rate of renewable energy and the comprehensive utilization of energy also have a positive impact on the auction equilibrium. In the end, this paper puts forward a series of policy suggestions about micro-grid project auction. The research in this paper is of great significance to improve the auction quality of micro-grid projects and promote the sustainable development of micro-grid.

Oct4 targets regulatory nodes to modulate stem cell function.

Directory of Open Access Journals (Sweden)

Pearl A Campbell

2007-06-01

Full Text Available Stem cells are characterized by two defining features, the ability to self-renew and to differentiate into highly specialized cell types. The POU homeodomain transcription factor Oct4 (Pou5f1 is an essential mediator of the embryonic stem cell state and has been implicated in lineage specific differentiation, adult stem cell identity, and cancer. Recent description of the regulatory networks which maintain 'ES' have highlighted a dual role for Oct4 in the transcriptional activation of genes required to maintain self-renewal and pluripotency while concomitantly repressing genes which facilitate lineage specific differentiation. However, the molecular mechanism by which Oct4 mediates differential activation or repression at these loci to either maintain stem cell identity or facilitate the emergence of alternate transcriptional programs required for the realization of lineage remains to be elucidated. To further investigate Oct4 function, we employed gene expression profiling together with a robust statistical analysis to identify genes highly correlated to Oct4. Gene Ontology analysis to categorize overrepresented genes has led to the identification of themes which may prove essential to stem cell identity, including chromatin structure, nuclear architecture, cell cycle control, DNA repair, and apoptosis. Our experiments have identified previously unappreciated roles for Oct4 for firstly, regulating chromatin structure in a state consistent with self-renewal and pluripotency, and secondly, facilitating the expression of genes that keeps the cell poised to respond to cues that lead to differentiation. Together, these data define the mechanism by which Oct4 orchestrates cellular regulatory pathways to enforce the stem cell state and provides important insight into stem cell function and cancer.

Obstructive pulmonary disease in patients with previous tuberculosis ...

African Journals Online (AJOL)

Obstructive pulmonary disease in patients with previous tuberculosis: Pathophysiology of a community-based cohort. B.W. Allwood, R Gillespie, M Galperin-Aizenberg, M Bateman, H Olckers, L Taborda-Barata, G.L. Calligaro, Q Said-Hartley, R van Zyl-Smit, C.B. Cooper, E van Rikxoort, J Goldin, N Beyers, E.D. Bateman ...

Cyclin E-Mediated Human Proopiomelanocortin Regulation as a Therapeutic Target for Cushing Disease.

Science.gov (United States)

Liu, Ning-Ai; Araki, Takako; Cuevas-Ramos, Daniel; Hong, Jiang; Ben-Shlomo, Anat; Tone, Yukiko; Tone, Masahide; Melmed, Shlomo

2015-07-01

/E2F1 signaling is a previously unappreciated molecular mechanism underlying neuroendocrine regulation of the hypothalamic-pituitary-adrenal axis, providing a subcellular therapeutic target for small molecule cyclin-dependent kinase 2 inhibitors of pituitary ACTH-dependent hypercortisolism, ie, Cushing disease.

"Nobody Appreciates What I Do." Overprotection as a Family Problem.

Science.gov (United States)

Schleifer, Maxwell J., Ed.

1991-01-01

In counseling sessions, a family with an adolescent son who has physical and academic problems comes to realize that each parent feels unappreciated for his or her efforts and that the father is overprotecting his son by not permitting him to solve his own problems and make his own decisions. (JDD)

Mechanism of prostatic urethroplasty with balloon catheter

International Nuclear Information System (INIS)

Castaneda, F.; Maynar, M.; Hulbert, J.

1988-01-01

A series of 60 patients have undergone prostatic urethroplasty with balloon catheters at our institution. The follow-up of these patients has ranged from more than 3 years to not less than 6 months. The preliminary results have been excellent, with a success rate of 75% in patients with predominant lateral lobe hypertrophy. This success rate drops to 25% in patients with predominant middle lobe hypertrophy. In previous communications the authors have proposed that the mechanism of prostatic urethral relief of obstruction is due to stretching of the prostatic capsule, tissue compression, and possible subsequent atrophy, as suggested by findings of transrectal US, MR imaging, voiding and retrograde urethrography, and urinary flow studies. Recent clinical information that has led to further animal research has shown that in addition to the previously supposed mechanism of action, separation of the prostatic lobes occurs by splitting of the anterior and posterior commissures of the prostatic gland tissue. This separation of the prostatic lobes is therefore the goal of the procedure. As more experience is gained, the already high success rate can probably be improved

Secondary mechanisms in a gas discharge

International Nuclear Information System (INIS)

Fletcher, J.; Blevin, H.A.

1978-05-01

The technique for studying swarms of electrons in a gas discharge by observing the photon flux from the discharge has been adapted to investigate the role of the secondary mechanisms. First results, reported here, show that, contrary to previous indications, ion bombardment of the cathode plays only a negligible, if any, part in the low pressure discharge in hydrogen at E/N approx. less than 200Td

Matched cohort study of external cephalic version in women with previous cesarean delivery.

Science.gov (United States)

Keepanasseril, Anish; Anand, Keerthana; Soundara Raghavan, Subrahmanian

2017-07-01

To evaluate the efficacy and safety of external cephalic version (ECV) among women with previous cesarean delivery. A retrospective study was conducted using data for women with previous cesarean delivery and breech presentation who underwent ECV at or after 36 weeks of pregnancy during 2011-2016. For every case, two multiparous women without previous cesarean delivery who underwent ECV and were matched for age and pregnancy duration were included. Characteristics and outcomes were compared between groups. ECV was successful for 32 (84.2%) of 38 women with previous cesarean delivery and 62 (81.6%) in the control group (P=0.728). Multivariate regression analysis confirmed that previous cesarean was not associated with ECV success (odds ratio 1.89, 95% confidence interval 0.19-18.47; P=0.244). Successful vaginal delivery after successful ECV was reported for 19 (59.4%) women in the previous cesarean delivery group and 52 (83.9%) in the control group (P<0.001). No ECV-associated complications occurred in women with previous cesarean delivery. To avoid a repeat cesarean delivery, ECV can be offered to women with breech presentation and previous cesarean delivery who are otherwise eligible for a trial of labor. © 2017 International Federation of Gynecology and Obstetrics.

Quantum Mechanics/Molecular Mechanics Modeling of Drug Metabolism: Mexiletine N-Hydroxylation by Cytochrome P450 1A2.

Science.gov (United States)

Lonsdale, Richard; Fort, Rachel M; Rydberg, Patrik; Harvey, Jeremy N; Mulholland, Adrian J

2016-06-20

The mechanism of cytochrome P450(CYP)-catalyzed hydroxylation of primary amines is currently unclear and is relevant to drug metabolism; previous small model calculations have suggested two possible mechanisms: direct N-oxidation and H-abstraction/rebound. We have modeled the N-hydroxylation of (R)-mexiletine in CYP1A2 with hybrid quantum mechanics/molecular mechanics (QM/MM) methods, providing a more detailed and realistic model. Multiple reaction barriers have been calculated at the QM(B3LYP-D)/MM(CHARMM27) level for the direct N-oxidation and H-abstraction/rebound mechanisms. Our calculated barriers indicate that the direct N-oxidation mechanism is preferred and proceeds via the doublet spin state of Compound I. Molecular dynamics simulations indicate that the presence of an ordered water molecule in the active site assists in the binding of mexiletine in the active site, but this is not a prerequisite for reaction via either mechanism. Several active site residues play a role in the binding of mexiletine in the active site, including Thr124 and Phe226. This work reveals key details of the N-hydroxylation of mexiletine and further demonstrates that mechanistic studies using QM/MM methods are useful for understanding drug metabolism.

Attribute and topology based change detection in a constellation of previously detected objects

Science.gov (United States)

Paglieroni, David W.; Beer, Reginald N.

2016-01-19

A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.

A deformation quantization theory for noncommutative quantum mechanics

International Nuclear Information System (INIS)

Costa Dias, Nuno; Prata, Joao Nuno; Gosson, Maurice de; Luef, Franz

2010-01-01

We show that the deformation quantization of noncommutative quantum mechanics previously considered by Dias and Prata ['Weyl-Wigner formulation of noncommutative quantum mechanics', J. Math. Phys. 49, 072101 (2008)] and Bastos, Dias, and Prata ['Wigner measures in non-commutative quantum mechanics', e-print arXiv:math-ph/0907.4438v1; Commun. Math. Phys. (to appear)] can be expressed as a Weyl calculus on a double phase space. We study the properties of the star-product thus defined and prove a spectral theorem for the star-genvalue equation using an extension of the methods recently initiated by de Gosson and Luef ['A new approach to the *-genvalue equation', Lett. Math. Phys. 85, 173-183 (2008)].

The mechanical response of lithographically defined break junctions

International Nuclear Information System (INIS)

Huisman, E. H.; Bakker, F. L.; Wees, B. J. van; Trouwborst, M. L.; Molen, S. J. van der

2011-01-01

We present an experimental study on the mechanical response of lithographically defined break junctions by measuring atomic chain formation, tunneling traces and Gundlach oscillations. The calibration factor, i.e., the ratio between the electrode movement and the bending of the substrate, is found to be 2.5 times larger than expected from a simple mechanical model. This result is consistent with previous finite-element calculations. Comparing different samples, the mechanical response is found to be similar for electrode separations >4 A. However, for smaller electrode separations significant sample-to-sample variations appear. These variations are ascribed to differences in the shape of the two electrodes on the atomic scale which cannot be controlled by the fabrication process.

Phonon spectrum, mechanical and thermophysical properties of thorium carbide

International Nuclear Information System (INIS)

Pérez Daroca, D.; Jaroszewicz, S.; Llois, A.M.; Mosca, H.O.

2013-01-01

In this work, we study, by means of density functional perturbation theory and the pseudopotential method, mechanical and thermophysical properties of thorium carbide. These properties are derived from the lattice dynamics in the quasi-harmonic approximation. The phonon spectrum of ThC presented in this article, to the best authors’ knowledge, have not been studied, neither experimentally, nor theoretically. We compare mechanical properties, volume thermal expansion and molar specific capacities with previous results and find a very good agreement

Phonon spectrum, mechanical and thermophysical properties of thorium carbide

Energy Technology Data Exchange (ETDEWEB)

Pérez Daroca, D., E-mail: pdaroca@tandar.cnea.gov.ar [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Consejo Nacional de Investigaciones Cientı´ficas y Técnicas (Argentina); Jaroszewicz, S. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA (Argentina); Llois, A.M. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Consejo Nacional de Investigaciones Cientı´ficas y Técnicas (Argentina); Mosca, H.O. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA (Argentina)

2013-06-15

In this work, we study, by means of density functional perturbation theory and the pseudopotential method, mechanical and thermophysical properties of thorium carbide. These properties are derived from the lattice dynamics in the quasi-harmonic approximation. The phonon spectrum of ThC presented in this article, to the best authors’ knowledge, have not been studied, neither experimentally, nor theoretically. We compare mechanical properties, volume thermal expansion and molar specific capacities with previous results and find a very good agreement.

Outcomes With Edoxaban Versus Warfarin in Patients With Previous Cerebrovascular Events

DEFF Research Database (Denmark)

Rost, Natalia S; Giugliano, Robert P; Ruff, Christian T

2016-01-01

BACKGROUND AND PURPOSE: Patients with atrial fibrillation and previous ischemic stroke (IS)/transient ischemic attack (TIA) are at high risk of recurrent cerebrovascular events despite anticoagulation. In this prespecified subgroup analysis, we compared warfarin with edoxaban in patients with ver......BACKGROUND AND PURPOSE: Patients with atrial fibrillation and previous ischemic stroke (IS)/transient ischemic attack (TIA) are at high risk of recurrent cerebrovascular events despite anticoagulation. In this prespecified subgroup analysis, we compared warfarin with edoxaban in patients...... with versus without previous IS/TIA. METHODS: ENGAGE AF-TIMI 48 (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48) was a double-blind trial of 21 105 patients with atrial fibrillation randomized to warfarin (international normalized ratio......). Because only HDER is approved, we focused on the comparison of HDER versus warfarin. RESULTS: Of 5973 (28.3%) patients with previous IS/TIA, 67% had CHADS2 (congestive heart failure, hypertension, age, diabetes, prior stroke/transient ischemic attack) >3 and 36% were ≥75 years. Compared with 15 132...

Azobenzene as a photoregulator covalently attached to RNA: a quantum mechanics/molecular mechanics-surface hopping dynamics study.

Science.gov (United States)

Mondal, Padmabati; Granucci, Giovanni; Rastädter, Dominique; Persico, Maurizio; Burghardt, Irene

2018-05-28

The photoregulation of nucleic acids by azobenzene photoswitches has recently attracted considerable interest in the context of emerging biotechnological applications. To understand the mechanism of photoinduced isomerisation and conformational control in these complex biological environments, we employ a Quantum Mechanics/Molecular Mechanics (QM/MM) approach in conjunction with nonadiabatic Surface Hopping (SH) dynamics. Two representative RNA-azobenzene complexes are investigated, both of which contain the azobenzene chromophore covalently attached to an RNA double strand via a β-deoxyribose linker. Due to the pronounced constraints of the local RNA environment, it is found that trans -to- cis isomerization is slowed down to a time scale of ∼10-15 picoseconds, in contrast to 500 femtoseconds in vacuo , with a quantum yield reduced by a factor of two. By contrast, cis -to- trans isomerization remains in a sub-picosecond regime. A volume-conserving isomerization mechanism is found, similarly to the pedal-like mechanism previously identified for azobenzene in solution phase. Strikingly, the chiral RNA environment induces opposite right-handed and left-handed helicities of the ground-state cis -azobenzene chromophore in the two RNA-azobenzene complexes, along with an almost completely chirality conserving photochemical pathway for these helical enantiomers.

Mechanism-Based Causal Reasoning in Young Children

Science.gov (United States)

Buchanan, David W.; Sobel, David M.

2011-01-01

The hypothesis that children develop an understanding of causal mechanisms was tested across 3 experiments. In Experiment 1 (N = 48), preschoolers had to choose as efficacious either a cause that had worked in the past, but was now disconnected from its effect, or a cause that had failed to work previously, but was now connected. Four-year-olds…

The Kaiser Wilhelm Society under National Socialism

CERN Document Server

Sachse, Carola; Walker, Mark

2009-01-01

During the first part of the twentieth century, German science led the world. The most important scientific institution in Germany was the Kaiser Wilhelm Society, including institutes devoted to different fields of scientific research. These researchers were not burdened by teaching obligations and enjoyed excellent financial and material support. When the National Socialists came to power in Germany, all of German society, including science, was affected. The picture that previously dominated our understanding of science under National Socialism from the end of the Second World War to the recent past - a picture of leading Nazis ignorant and unappreciative of modern science and of scientists struggling to resist the Nazis - needs to be revised. This book surveys the history of Kaiser Wilhelm Institutes under Hitler, illustrating definitively the cooperation, if not collaboration, between scientists and National Socialists in order to further the goals of autarky, racial hygiene, war, and genocide.

New insights into the catalytic mechanism of human glycine N-acyltransferase.

Science.gov (United States)

van der Sluis, Rencia; Ungerer, Vida; Nortje, Carla; A van Dijk, Alberdina; Erasmus, Elardus

2017-11-01

Even though the glycine conjugation pathway was one of the first metabolic pathways to be discovered, this pathway remains very poorly characterized. The bi-substrate kinetic parameters of a recombinant human glycine N-acyltransferase (GLYAT, E.C. 2.3.1.13) were determined using the traditional colorimetric method and a newly developed HPLC-ESI-MS/MS method. Previous studies analyzing the kinetic parameters of GLYAT, indicated a random Bi-Bi and/or ping-pong mechanism. In this study, the hippuric acid concentrations produced by the GLYAT enzyme reaction were analyzed using the allosteric sigmoidal enzyme kinetic module. Analyses of the initial rate (v) against substrate concentration plots, produced a sigmoidal curve (substrate activation) when the benzoyl-CoA concentrations was kept constant, whereas the plot with glycine concentrations kept constant, passed through a maximum (substrate inhibition). Thus, human GLYAT exhibits mechanistic kinetic cooperativity as described by the Ferdinand enzyme mechanism rather than the previously assumed Michaelis-Menten reaction mechanism. © 2017 Wiley Periodicals, Inc.

75 FR 66009 - Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia...

Science.gov (United States)

2010-10-27

... Company (Type Certificate Previously Held by Columbia Aircraft Manufacturing (Previously the Lancair... Company (Type Certificate Previously Held by Columbia Aircraft Manufacturing (Previously The Lancair...-15895. Applicability (c) This AD applies to the following Cessna Aircraft Company (type certificate...

Integrating cognitive (neuroscience using mechanisms

Directory of Open Access Journals (Sweden)

Marcin Miłkowski

2016-11-01

Full Text Available In this paper, an account of theoretical integration in cognitive (neuroscience from the mechanistic perspective is defended. It is argued that mechanistic patterns of integration can be better understood in terms of constraints on representations of mechanisms, not just on the space of possible mechanisms, as previous accounts of integration had it. This way, integration can be analyzed in more detail with the help of constraintsatisfaction account of coherence between scientific represen-tations. In particular, the account has resources to talk of idealizations and research heuristics employed by researchers to combine separate results and theoretical frameworks. The account is subsequently applied to an example of successful integration in the research on hippocampus and memory, and to a failure of integration in the research on mirror neurons as purportedly explanatory of sexual orientation.

[Fatal amnioinfusion with previous choriocarcinoma in a parturient woman].

Science.gov (United States)

Hrgović, Z; Bukovic, D; Mrcela, M; Hrgović, I; Siebzehnrübl, E; Karelovic, D

2004-04-01

The case of 36-year-old tercipare is described who developed choriocharcinoma in a previous pregnancy. During the first term labour the patient developed cardiac arrest, so reanimation and sectio cesarea was performed. A male new-born was delivered in good condition, but even after intensive therapy and reanimation occurred death of parturient woman with picture of disseminate intravascular coagulopathia (DIK). On autopsy and on histology there was no sign of malignant disease, so it was not possible to connect previous choricarcinoma with amniotic fluid embolism. Maybe was place of choriocarcinoma "locus minoris resistentiae" which later resulted with failure in placentation what was hard to prove. On autopsy we found embolia of lung with a microthrombosis of terminal circulation with punctiformis bleeding in mucous, what stands for DIK.

Statistical mechanics and the evolution of polygenic quantitative traits

NARCIS (Netherlands)

Barton, N.H.; De Vladar, H.P.

The evolution of quantitative characters depends on the frequencies of the alleles involved, yet these frequencies cannot usually be measured. Previous groups have proposed an approximation to the dynamics of quantitative traits, based on an analogy with statistical mechanics. We present a modified

Air rudder mechanism dynamics considering two elements:Joint clearance and link flexibility

Energy Technology Data Exchange (ETDEWEB)

Li, Yuntao; Quan, Qiquan; Li, He; Tang, Dewei; Li, Zhonghong; Fan, Wenyang; Deng, Zongquan [Harbin Institute of Technology, Harbin (China)

2017-07-15

Both the impact phenomenon in the clearance revolute joint and the link deformation will influence the dynamics of the air rudder transmission mechanism, which could reduce the flight quality of an aircraft. Given the effect of the two elements, a feasible simulation method with two improvements of previous methods is proposed to analyze the dynamic characteristics of the mechanism. In previous studies, the parameters of the contact force model in multi-body dynamics software were generally determined by experience, which may cause uncertainty in the calculation precision of the contact force. Furthermore, it is difficult to solve for the elastic link deformation in the practical mechanism using the available analytical methods due to the complicated section of the link. In this paper, a Continuous contact force (CCF) model was proposed and embedded in the ADAMS by developing a routine of the CCF model. Then, the flexible model was obtained by ANSYS to obtain the elastic link deformation. The experimental results indicate that the proposed simulation method can be effectively applied to predict the dynamic behavior of the mechanism.

Advances on research epigenetic change of hybrid and polyploidy ...

African Journals Online (AJOL)

A large proportion of these variations are epigenetic in nature. Epigenetic can be defined as a change of the study in the regulation of gene activity and expression that are not driven by gene sequence information. However, the ramifications of epigenetic in plant biology are immense, yet unappreciated. In contrast to the ...

Are Listening Skills Best Enhanced through the Use of Multimedia Technology

Science.gov (United States)

Sejdiu, Sejdi

2017-01-01

Listening comprehension is essential to L2 learning. Pupils who are able to demonstrate L2 listening skills are able to demonstrate proficiency in other language skills. Due to the relatively unappreciated role of listening in language development, educators and language experts have been actively promoting the equal or emphasized enhancement of…

Let's put "care" back into health care.

Science.gov (United States)

Wesolowski, C E

1990-01-01

Organizations that clearly demonstrate they care about their people reap the benefits of a positive self-image, higher productivity and financial gains. Consider the effects that a demoralized, unappreciated staff have on productivity, recruitment and retention, public relations, marketing, customer satisfaction and the resulting financial repercussions. Can we afford not to care?

Detection and Location of Structural Degradation in Mechanical Systems

International Nuclear Information System (INIS)

Blakeman, E.D.; Damiano, B.; Phillips, L.D.

1999-01-01

The investigation of a diagnostic method for detecting and locating the source of structural degradation in a mechanical system is described in this paper. The diagnostic method uses a mathematical model of the mechanical system to determine relationships between system parameters and measurable spectral features. These relationships are incorporated into a neural network, which associates measured spectral features with system parameters. Condition diagnosis is performed by presenting the neural network with measured spectral features and comparing the system parameters estimated by the neural network to previously estimated values. Changes in the estimated system parameters indicate the location and severity of degradation in the mechanical system

Does previous use affect litter box appeal in multi-cat households?

Science.gov (United States)

Ellis, J J; McGowan, R T S; Martin, F

2017-08-01

It is commonly assumed that cats actively avoid eliminated materials (especially in multi-cat homes), suggesting regular litter box cleaning as the best defense against out-of-box elimination. The relationship between previous use and litter box appeal to familiar subsequent users is currently unknown. The purpose of this study was to investigate the relationship between previous litter box use and the identity of the previous user, type of elimination, odor, and presence of physical/visual obstructions in a multi-cat household scenario. Cats preferred a clean litter box to a dirty one, but the identity of the previous user had no impact on preferences. While the presence of odor from urine and/or feces did not impact litter box preferences, the presence of odorless faux-urine and/or feces did - with the presence of faux-feces being preferred over faux-urine. Results suggest neither malodor nor chemical communication play a role in litter box preferences, and instead emphasize the importance of regular removal of physical/visual obstructions as the key factor in promoting proper litter box use. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

A cross-culture, cross-gender comparison of perspective taking mechanisms

OpenAIRE

Kessler, Klaus; Cao, Liyu; O'Shea, Kieran J.; Wang, Hong Fang

2014-01-01

Being able to judge another person's visuo-spatial perspective is an essential social skill, hence we investigated the generalizability of the involved mechanisms across cultures and genders. Developmental, cross-species, and our own previous research suggest that two different forms of perspective taking can be distinguished, which are subserved by two distinct mechanisms. The simpler form relies on inferring another's line-of-sight, whereas the more complex form depends on embodied transfor...

Low-dose computed tomography image restoration using previous normal-dose scan

International Nuclear Information System (INIS)

Ma, Jianhua; Huang, Jing; Feng, Qianjin; Zhang, Hua; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan

2011-01-01

Purpose: In current computed tomography (CT) examinations, the associated x-ray radiation dose is of a significant concern to patients and operators. A simple and cost-effective means to perform the examinations is to lower the milliampere-seconds (mAs) or kVp parameter (or delivering less x-ray energy to the body) as low as reasonably achievable in data acquisition. However, lowering the mAs parameter will unavoidably increase data noise and the noise would propagate into the CT image if no adequate noise control is applied during image reconstruction. Since a normal-dose high diagnostic CT image scanned previously may be available in some clinical applications, such as CT perfusion imaging and CT angiography (CTA), this paper presents an innovative way to utilize the normal-dose scan as a priori information to induce signal restoration of the current low-dose CT image series. Methods: Unlike conventional local operations on neighboring image voxels, nonlocal means (NLM) algorithm utilizes the redundancy of information across the whole image. This paper adapts the NLM to utilize the redundancy of information in the previous normal-dose scan and further exploits ways to optimize the nonlocal weights for low-dose image restoration in the NLM framework. The resulting algorithm is called the previous normal-dose scan induced nonlocal means (ndiNLM). Because of the optimized nature of nonlocal weights calculation, the ndiNLM algorithm does not depend heavily on image registration between the current low-dose and the previous normal-dose CT scans. Furthermore, the smoothing parameter involved in the ndiNLM algorithm can be adaptively estimated based on the image noise relationship between the current low-dose and the previous normal-dose scanning protocols. Results: Qualitative and quantitative evaluations were carried out on a physical phantom as well as clinical abdominal and brain perfusion CT scans in terms of accuracy and resolution properties. The gain by the use

Mechanical transport and dissemination of soil-transmitted helminth ...

African Journals Online (AJOL)

In previous studies, helminth eggs were isolated from wild-caught Musca domestica L. (Diptera: Muscidae). This laboratory study investigated the potential of the fly for mechanical transport and transmission of soil-transmitted helminths. Naïve, 2-3 day old, laboratory-reared adult flies were exposed to a mixture of Ascaris ...

Modeling the dynamic response of pressures in a distributed helium refrigeration system

International Nuclear Information System (INIS)

Brubaker, J.C.

1997-12-01

A mathematical model is created of the dynamic response of pressures caused by flow inputs to an existing distributed helium refrigeration system. The dynamic system studied consists of the suction and discharge pressure headers and compressor portions of the refrigeration system used to cool the superconducting magnets of the Tevatron accelerator at the Fermi National Accelerator Laboratory. The modeling method involves identifying the system from data recorded during a series of controlled tests, with effort made to detect locational differences in pressure response around the four mile accelerator circumference. A review of the fluid mechanics associated with the system indicates linear time invariant models are suitable for the identification, particularly since the governing equations of one dimensional fluid flow are approximated by linear differential equations. An outline of the experimental design and the data acquisition system are given, followed by a detailed description of the modeling, which utilized the Matlab programming language and associated System Identification Toolbox. Two representations of the system are presented. One, a black box model, provides a multi-input, multi-output description assembled from the results of single input step function testing. This description indicates definite variation in pressure response with distance from the flow input location, and also suggests subtle differences in response with the input location itself. A second system representation is proposed which details the relation between continuous flow changes and pressure response, and provides explanation of a previously unappreciated pressure feedback internal to the system

Inhibiting prenylation augments chemotherapy efficacy in renal cell carcinoma through dual inhibition on mitochondrial respiration and glycolysis.

Science.gov (United States)

Huang, Jiangrong; Yang, Xiaoyu; Peng, Xiaochun; Huang, Wei

2017-11-18

Prenylation is a posttranslational lipid modification required for the proper functions of a number of proteins involved in cell regulation. Here, we show that prenylation inhibition is important for renal cell carcinoma (RCC) growth, survival and response to chemotherapy, and its underlying mechanism may be contributed to mitochondrial dysfunction. We first demonstrated that a HMG-CoA reductase inhibitor pitavastatin inhibited mevalonate pathway and thereby prenylation in RCC cells. In addition, pitavastatin is effective in inhibiting growth and inducing apoptosis in a panel of RCC cell lines. Combination of pitavastatin and paclitaxel is significantly more effective than pitavastatin or paclitaxel alone as shown by both in vitro cell culture system and in vivo RCC xenograft model. Importantly, pitavastatin treatment inhibits mitochondrial respiration via suppressing mitochondrial complex I and II enzyme activities. Interestingly, different from mitochondrial inhibitor phenformin that inhibits mitochondrial respiration but activates glycolytic rate in RCC cells, pitavastatin significantly decreases glycolytic rate. The dual inhibitory action of pitavastatin on mitochondrial respiration and glycolysis results in remarkable energy depletion and oxidative stress in RCC cells. In addition, inhibition of prenylation by depleting Isoprenylcysteine carboxylmethyltransferase (Icmt) also mimics the inhibitory effects of pitavastatin in RCC cells. Our work demonstrates the previously unappreciated association between prenylation inhibition and energy metabolism in RCC, which can be therapeutically exploited, likely in tumors that largely rely on energy metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

The Extracellular Matrix Regulates Granuloma Necrosis in Tuberculosis.

Science.gov (United States)

Al Shammari, Basim; Shiomi, Takayuki; Tezera, Liku; Bielecka, Magdalena K; Workman, Victoria; Sathyamoorthy, Tarangini; Mauri, Francesco; Jayasinghe, Suwan N; Robertson, Brian D; D'Armiento, Jeanine; Friedland, Jon S; Elkington, Paul T

2015-08-01

A central tenet of tuberculosis pathogenesis is that caseous necrosis leads to extracellular matrix destruction and bacterial transmission. We reconsider the underlying mechanism of tuberculosis pathology and demonstrate that collagen destruction may be a critical initial event, causing caseous necrosis as opposed to resulting from it. In human tuberculosis granulomas, regions of extracellular matrix destruction map to areas of caseous necrosis. In mice, transgenic expression of human matrix metalloproteinase 1 causes caseous necrosis, the pathological hallmark of human tuberculosis. Collagen destruction is the principal pathological difference between humanised mice and wild-type mice with tuberculosis, whereas the release of proinflammatory cytokines does not differ, demonstrating that collagen breakdown may lead to cell death and caseation. To investigate this hypothesis, we developed a 3-dimensional cell culture model of tuberculosis granuloma formation, using bioelectrospray technology. Collagen improved survival of Mycobacterium tuberculosis-infected cells analyzed on the basis of a lactate dehydrogenase release assay, propidium iodide staining, and measurement of the total number of viable cells. Taken together, these findings suggest that collagen destruction is an initial event in tuberculosis immunopathology, leading to caseous necrosis and compromising the immune response, revealing a previously unappreciated role for the extracellular matrix in regulating the host-pathogen interaction. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Modeling the dynamic response of pressures in a distributed helium refrigeration system

Energy Technology Data Exchange (ETDEWEB)

Brubaker, John Carl [Illinois Inst. of Technology, Chicago, IL (United States)

1997-12-01

A mathematical model is created of the dynamic response of pressures caused by flow inputs to an existing distributed helium refrigeration system. The dynamic system studied consists of the suction and discharge pressure headers and compressor portions of the refrigeration system used to cool the superconducting magnets of the Tevatron accelerator at the Fermi National Accelerator Laboratory. The modeling method involves identifying the system from data recorded during a series of controlled tests, with effort made to detect locational differences in pressure response around the four mile accelerator circumference. A review of the fluid mechanics associated with the system indicates linear time invariant models are suitable for the identification, particularly since the governing equations of one dimensional fluid flow are approximated by linear differential equations. An outline of the experimental design and the data acquisition system are given, followed by a detailed description of the modeling, which utilized the Matlab programming language and associated System Identification Toolbox. Two representations of the system are presented. One, a black box model, provides a multi-input, multi-output description assembled from the results of single input step function testing. This description indicates definite variation in pressure response with distance from the flow input location, and also suggests subtle differences in response with the input location itself. A second system representation is proposed which details the relation between continuous flow changes and pressure response, and provides explanation of a previously unappreciated pressure feedback internal to the system.

Theoretical physics 6 quantum mechanics : basics

CERN Document Server

Nolting, Wolfgang

2017-01-01

This textbook offers a clear and comprehensive introduction to the basics of quantum mechanics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, thus developing the physical understanding further on to quantized states. The first part of the book introduces wave equations while exploring the Schrödinger equation and the hydrogen atom. More complex themes are covered in the second part of the book, which describes the Dirac formulism of quantum mechanics. Ideally suited to undergraduate students with some grounding in classical mechanics and electrodynamics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this...

Parathyroid Hormone-Related Peptide: A Novel Endocrine Cardioprotective "Conditioning Mimetic".

Science.gov (United States)

Datta, Tanuka; Przyklenk, Karin; Datta, Nabanita S

2017-11-01

An as-yet limited body of evidence suggests that calcium-regulating endocrine hormones-in particular, parathyroid hormone-related peptide (PTHrP)-may have unappreciated cardioprotective effects. The current review focuses on the concept that PTHrP may, via modulation of classic cardioprotective signaling pathways, provide a novel strategy to attenuate myocardial ischemia-reperfusion injury.

Determination of signal intensity affected by Gaussian noise

International Nuclear Information System (INIS)

Blostein, Jeronimo J.; Bennun, Leonardo

1999-01-01

A methodology based on maximum likelihood criteria, to identify and quantify an arbitrary signal affected by Gaussian noise is shown. To use this methodology it is necessary to know the position in the spectrum where the signal of interest should appear, and the shape of the signal when the background is null or unappreciable. (author)

78 FR 36190 - Agency Information Collection Activities; Submission for OMB Review; IT Dashboard Feedback Mechanism

Science.gov (United States)

2013-06-17

... Information Collection Activities; Submission for OMB Review; IT Dashboard Feedback Mechanism AGENCY: Office... to review and approve a previously approved information collection requirement regarding IT Dashboard... identified by Information Collection 3090- 0285, IT Dashboard Feedback Mechanism, by any of the following...

Previous Exposure to the Fish Parasite Anisakis as a Potential Risk Factor for Gastric or Colon Adenocarcinoma.

Science.gov (United States)

Garcia-Perez, Juan Carlos; Rodríguez-Perez, Rosa; Ballestero, Araceli; Zuloaga, Jaime; Fernandez-Puntero, Belen; Arias-Díaz, Javier; Caballero, María Luisa

2015-10-01

Anisakiasis is a global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis spp. larvae. High rates of parasitization of fish worldwide make Anisakis a serious health hazard. In fact, anisakiasis is a growing disease in countries such as Spain, Italy, and Japan, where consumption of raw/marinated fish is high. Some parasitic infections have been recognized as a causative factor for human cancer. Suggested mechanisms include chronic inflammation elicited by the parasite, and a possible tumorigenic effect from certain parasitic secretions. Anisakis can produce persistent local inflammation and granuloma, and larvae have been incidentally found in gastrointestinal (GI) tumors. Our aim was to discover possible differences in the prevalence of unnoticed or asymptomatic previous Anisakis infection in GI cancer patients compared with healthy individuals. Serum levels of specific antibodies against Anisakis antigens were used as a reliable marker of previous contact with their larvae. Ninety-four participants without a previous history of Anisakis infection were prospectively allocated into 1 of 2 groups: 47 patients with GI cancer and 47 controls. Specific IgE, IgA1, and IgG1 against the Anisakis recombinant antigens Ani s 1, Ani s 5, Ani s 9, and Ani s 10 were determined by an ELISA assay. The ratio of positivity to sIgA1, rAni s 1, or rAni s 5 was significantly higher in the cancer patients than in the controls (38.30% vs 6.38%, P cancer showed a higher proportion of positive results for sIgA1 to rAni s 1 (P cancer patients were shown to be positive for sIgA1 to both rAni s 1 (P cancer.

Research Note Effects of previous cultivation on regeneration of ...

African Journals Online (AJOL)

We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...

Quantum mechanics, relativity and casuality

International Nuclear Information System (INIS)

Tati, T.

1976-01-01

In quantum mechanics, the state is prepared by a measurement on a spacelike surface sigma. What is that determine the surface sigma on which the measurement prepares the stae. It si considered either a mechanism proper to the measuring process (apparatus) or a universal property of space-time. In the former case, problems arise, concerning casuality or conservation of probability due to the fact that the velocity of reduction of a wave packet is considered to exceed the light velocity. The theory of finite degree of freedom proposed previously belongs to the latter case. In this theory, the surface sigma is restricted to the hyper-plane perpendicular to a universal time-like vector governing casual relations. An experimental to discriminate between the above-mentioned two cases and to test the existence of the universal timelike vector is proposed

Quantum mechanics, relativity and causality

International Nuclear Information System (INIS)

Tati, Takao.

1975-07-01

In quantum mechanics, the state is prepared by a measurement on a space-like surface sigma. What is that determines the surface sigma on which the measurement prepares the state It is considered either a mechanism proper to the measuring process (apparatus) or a universal property of space-time. In the former case, problems arise, concerning causality or conservation of probability due to that the velocity of reduction of wave-packet is considered to exceed the light velocity. The theory of finite degree of freedom proposed previously belongs to the latter case. In this theory, the surface sigma is restricted to the hyper-plane perpendicular to a universal time-like vector governing causal relations. We propose an experiment to discriminate between the above-mentioned two cases and to test the existence of the universal time-like vector. (auth.)

Quantum mechanics in noninertial reference frames: Violations of the nonrelativistic equivalence principle

International Nuclear Information System (INIS)

Klink, W.H.; Wickramasekara, S.

2014-01-01

In previous work we have developed a formulation of quantum mechanics in non-inertial reference frames. This formulation is grounded in a class of unitary cocycle representations of what we have called the Galilean line group, the generalization of the Galilei group that includes transformations amongst non-inertial reference frames. These representations show that in quantum mechanics, just as is the case in classical mechanics, the transformations to accelerating reference frames give rise to fictitious forces. A special feature of these previously constructed representations is that they all respect the non-relativistic equivalence principle, wherein the fictitious forces associated with linear acceleration can equivalently be described by gravitational forces. In this paper we exhibit a large class of cocycle representations of the Galilean line group that violate the equivalence principle. Nevertheless the classical mechanics analogue of these cocycle representations all respect the equivalence principle. -- Highlights: •A formulation of Galilean quantum mechanics in non-inertial reference frames is given. •The key concept is the Galilean line group, an infinite dimensional group. •A large class of general cocycle representations of the Galilean line group is constructed. •These representations show violations of the equivalence principle at the quantum level. •At the classical limit, no violations of the equivalence principle are detected

Strategies for mechanism reduction for large hydrocarbons: n-heptane

Energy Technology Data Exchange (ETDEWEB)

Lu, Tianfeng; Law, Chung K. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

2008-07-15

A 55-species reduced mechanism for n-heptane oxidation was derived from a 188-species skeletal mechanism, which was previously obtained from a detailed mechanism consisting of 561 species using a directed relation graph (DRG). This reduced mechanism was derived by first obtaining a skeletal mechanism with 78 species using DRG-aided sensitivity analysis. The unimportant reactions were eliminated by using the importance index defined in computational singular perturbation (CSP), with a newly posited restriction to treat each reversible reaction as a single reaction. An isomer lumping approach, also developed in the present study, then groups the isomers with similar thermal and diffusion properties so that the number of species transport equations is reduced. It was found that the intragroup mass fractions of the isomers can be approximated as constants in the present reduced mechanism, leading to a 68-species mechanism with 283 elementary reactions. Finally, 13 global quasi-steady-state species were identified using a CSP-based time-scale analysis, resulting in the 55-species reduced mechanism, with 283 elementary reactions lumped into 51 semiglobal steps. Validation of the reduced mechanism shows good agreement with the detailed mechanism for both ignition and extinction phenomena. The inadequacy of the detailed mechanism in predicting the experimental laminar flame speed is also demonstrated. (author)

Does the patients′ educational level and previous counseling affect their medication knowledge?

Directory of Open Access Journals (Sweden)

Abdulmalik M Alkatheri

2013-01-01

Conclusions: The education level of the patient and previous counseling are positively linked to medication knowledge. Knowledge of the medications′ side effects proved to be the most difficult task for the participants in this study, requiring the highest level of education, and was improved by previous counseling.

The job satisfaction of principals of previously disadvantaged schools

African Journals Online (AJOL)

The aim of this study was to identify influences on the job satisfaction of previously disadvantaged ..... I am still riding the cloud … I hope it lasts. .... as a way of creating a climate and culture in schools where individuals are willing to explore.

Mechanical ventilation in abdominal surgery.

Science.gov (United States)

Futier, E; Godet, T; Millot, A; Constantin, J-M; Jaber, S

2014-01-01

One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEPventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery. Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

Predictive factors for the development of diabetes in women with previous gestational diabetes mellitus

DEFF Research Database (Denmark)

Damm, P.; Kühl, C.; Bertelsen, Aksel

1992-01-01

OBJECTIVES: The purpose of this study was to determine the incidence of diabetes in women with previous dietary-treated gestational diabetes mellitus and to identify predictive factors for development of diabetes. STUDY DESIGN: Two to 11 years post partum, glucose tolerance was investigated in 241...... women with previous dietary-treated gestational diabetes mellitus and 57 women without previous gestational diabetes mellitus (control group). RESULTS: Diabetes developed in 42 (17.4%) women with previous gestational diabetes mellitus (3.7% insulin-dependent diabetes mellitus and 13.7% non...... of previous patients with gestational diabetes mellitus in whom plasma insulin was measured during an oral glucose tolerance test in late pregnancy a low insulin response at diagnosis was found to be an independent predictive factor for diabetes development. CONCLUSIONS: Women with previous dietary...

Kidnapping Detection and Recognition in Previous Unknown Environment

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Yang Tian

2017-01-01

Full Text Available An unaware event referred to as kidnapping makes the estimation result of localization incorrect. In a previous unknown environment, incorrect localization result causes incorrect mapping result in Simultaneous Localization and Mapping (SLAM by kidnapping. In this situation, the explored area and unexplored area are divided to make the kidnapping recovery difficult. To provide sufficient information on kidnapping, a framework to judge whether kidnapping has occurred and to identify the type of kidnapping with filter-based SLAM is proposed. The framework is called double kidnapping detection and recognition (DKDR by performing two checks before and after the “update” process with different metrics in real time. To explain one of the principles of DKDR, we describe a property of filter-based SLAM that corrects the mapping result of the environment using the current observations after the “update” process. Two classical filter-based SLAM algorithms, Extend Kalman Filter (EKF SLAM and Particle Filter (PF SLAM, are modified to show that DKDR can be simply and widely applied in existing filter-based SLAM algorithms. Furthermore, a technique to determine the adapted thresholds of metrics in real time without previous data is presented. Both simulated and experimental results demonstrate the validity and accuracy of the proposed method.

Davidson's generalization of the Fenyes-Nelson stochastic model of quantum mechanics

International Nuclear Information System (INIS)

Shucker, D.S.

1980-01-01

Davidson's generalization of the Fenyes-Nelson stochastic model of quantum mechanics is discussed. It is shown that this author's previous results concerning the Fenyes-Nelson process extend to the more general theory of Davidson. (orig.)

Outcome of trial of scar in patients with previous caesarean section

International Nuclear Information System (INIS)

Khan, B.; Bashir, R.; Khan, W.

2016-01-01

Medical evidence indicates that 60-80% of women can achieve vaginal delivery after a previous lower segment caesarean section. Proper selection of patients for trial of scar and vigilant monitoring during labour will achieve successful maternal and perinatal outcome. The objective of our study is to establish the fact that vaginal delivery after one caesarean section has a high success rate in patients with previous one caesarean section for non-recurrent cause. Methods: The study was conducted in Ayub Teaching Abbottabad, Gynae-B Unit. All labouring patients, during the study period of five years, with previous one caesarean section and between 37 weeks to 41 weeks of gestation for a non-recurrent cause were included in the study. Data was recorded on special proforma designed for the purpose. Patients who had previous classical caesarean section, more than one caesarean section, and previous caesarean section with severe wound infection, transverse lie and placenta previa in present pregnancy were excluded. Foetal macrosomia (wt>4 kg) and severe IUGR with compromised blood flow on Doppler in present pregnancy were also not considered suitable for the study. Patients who had any absolute contraindication for vaginal delivery were also excluded. Results: There were 12505 deliveries during the study period. Total vaginal deliveries were 8790 and total caesarean sections were 3715. Caesarean section rate was 29.7%. Out of these 8790 patients, 764 patients were given a trial of scar and 535 patients delivered successfully vaginally (70%). Women who presented with spontaneous onset of labour were more likely to deliver vaginally (74.8%) as compared to induction group (27.1%). Conclusion: Trial of vaginal birth after caesarean (VBAC) in selected cases has great importance in the present era of the rising rate of primary caesarean section. (author)

Study of functional-performance deficits in athletes with previous ankle sprains

Directory of Open Access Journals (Sweden)

hamid Babaee

2008-04-01

Full Text Available Abstract Background: Despite the importance of functional-performance deficits in athletes with history of ankle sprain few, studies have been carried out in this area. The aim of this research was to study relationship between previous ankle sprains and functional-performance deficits in athletes. Materials and methods: The subjects were 40 professional athletes selected through random sampling among volunteer participants in soccer, basketball, volleyball and handball teams of Lorestan province. The subjects were divided into 2 groups: Injured group (athletes with previous ankle sprains and healthy group (athletes without previous ankle sprains. In this descriptive study we used Functional-performance tests (figure 8 hop test and side hop test to determine ankle deficits and limitations. They participated in figure 8 hop test including hopping in 8 shape course with the length of 5 meters and side hop test including 10 side hop repetitions in course with the length of 30 centimeters. Time were recorded via stopwatch. Results: After data gathering and assessing information distributions, Pearson correlation was used to assess relationships, and independent T test to assess differences between variables. Finally the results showed that there is a significant relationship between previous ankle sprains and functional-performance deficits in the athletes. Conclusion: The athletes who had previous ankle sprains indicated functional-performance deficits more than healthy athletes in completion of mentioned functional-performance tests. The functional-performance tests (figure 8 hop test and side hop test are sensitive and suitable to assess and detect functional-performance deficits in athletes. Therefore we can use the figure 8 hop and side hop tests for goals such as prevention, assessment and rehabilitation of ankle sprains without spending too much money and time.

From quantum mechanics to universal structures of conceptualization and feedback on quantum mechanics

International Nuclear Information System (INIS)

Mugur-Schaechter, M.

1993-01-01

In previous works we have established that the spacetime probabilistic organization of the quantum theory is determined by the spacetime characteristics of the operations by which the observer produces the objects to be studied (states of microsystems) and obtains qualifications of these. Guided by this first conclusion, we have then built a general syntax of relativized conceptualization where any description is explicity and systematically referred to the two basic epistemic operations by which the conceptor introduces the object to be qualified and then obtains qualifications of it. Inside this syntax there emerges a general typology of the relativized descriptions. Here we show that with respect to this typology the type of the predictive quantum mechanical descriptions acquires a precise definition. It appears that the quantum mechanical formalism has captured and has expressed directly in a mathematical language the most complex form in which can occur a first descriptional phase that lies universally at the bottom of any chain of conceptualization. The main features of the Hilbert-Dirac algorithms are decoded in terms of the general syntax of relativized conceptualiztion. This renders explicit the semantical contents of the quantum mechanical representations relating each one of these to its mathematical quantum mechanical expression. Basic insufficiencies are thus identified and, correlatively, false problems as well as answers to these, or guides towards the answers. Globally the results obtained provide a basis for the future attempts at a general mathematical representation of the processes of conceptualization

The prevalence of previous self-harm amongst self-poisoning patients in Sri Lanka

DEFF Research Database (Denmark)

Mohamed, Fahim; Perera, Aravinda; Wijayaweera, Kusal

2011-01-01

BACKGROUND: One of the most important components of suicide prevention strategies is to target people who repeat self-harm as they are a high risk group. However, there is some evidence that the incidence of repeat self-harm is lower in Asia than in the West. The objective of this study...... was to investigate the prevalence of previous self-harm among a consecutive series of self-harm patients presenting to hospitals in rural Sri Lanka. METHOD: Six hundred and ninety-eight self-poisoning patients presenting to medical wards at two hospitals in Sri Lanka were interviewed about their previous episodes...... of self-harm. RESULTS: Sixty-one (8.7%, 95% CI 6.7-11%) patients reported at least one previous episode of self-harm [37 (10.7%) male, 24 (6.8%) female]; only 19 (2.7%, 95% CI 1.6-4.2%) patients had made more than one previous attempt. CONCLUSION: The low prevalence of previous self-harm is consistent...

Charged-particle thermonuclear reaction rates: IV. Comparison to previous work

International Nuclear Information System (INIS)

Iliadis, C.; Longland, R.; Champagne, A.E.; Coc, A.

2010-01-01

We compare our Monte Carlo reaction rates (see Paper II of this issue) to previous results that were obtained by using the classical method of computing thermonuclear reaction rates. For each reaction, the comparison is presented using two types of graphs: the first shows the change in reaction rate uncertainties, while the second displays our new results normalized to the previously recommended reaction rate. We find that the rates have changed significantly for almost all reactions considered here. The changes are caused by (i) our new Monte Carlo method of computing reaction rates (see Paper I of this issue), and (ii) newly available nuclear physics information (see Paper III of this issue).

Analysis of previous perceptual and motor experience in breaststroke kick learning

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Ried Bettina

2015-12-01

Full Text Available One of the variables that influence motor learning is the learner’s previous experience, which may provide perceptual and motor elements to be transferred to a novel motor skill. For swimming skills, several motor experiences may prove effective. Purpose. The aim was to analyse the influence of previous experience in playing in water, swimming lessons, and music or dance lessons on learning the breaststroke kick. Methods. The study involved 39 Physical Education students possessing basic swimming skills, but not the breaststroke, who performed 400 acquisition trials followed by 50 retention and 50 transfer trials, during which stroke index as well as rhythmic and spatial configuration indices were mapped, and answered a yes/no questionnaire regarding previous experience. Data were analysed by ANOVA (p = 0.05 and the effect size (Cohen’s d ≥0.8 indicating large effect size. Results. The whole sample improved their stroke index and spatial configuration index, but not their rhythmic configuration index. Although differences between groups were not significant, two types of experience showed large practical effects on learning: childhood water playing experience only showed major practically relevant positive effects, and no experience in any of the three fields hampered the learning process. Conclusions. The results point towards diverse impact of previous experience regarding rhythmic activities, swimming lessons, and especially with playing in water during childhood, on learning the breaststroke kick.

Iodine-131 induced hepatotoxicity in previously healthy patients with Grave's disease.

Science.gov (United States)

Jhummon, Navina Priya; Tohooloo, Bhavna; Qu, Shen

2013-01-01

To describe the association of the rare and serious complication of liver toxicity in previously healthy Grave's disease (GD) patients after the treatment with radioactive iodine (131)I (RAI). We report the clinical, laboratory and pathologic findings of 2 cases of severe liver toxicity associated with the treatment with RAI in previously healthy patients with GD. Clinical examination and laboratory investigations excluded viral hepatitis, autoimmune hepatitis, granulomatous disease, primary biliary disease, extrahepatic biliary obstruction, and heart failure. Case 1: A previously healthy 52-years old man reportedly having a typical GD but following RAI treatment, concomitantly developed severe liver toxicity that required 1 week of treatment in hospital. Case 2: A previously healthy 34-years old woman is reported as having a typical GD but developed jaundice following RAI treatment that required several weeks of in hospital treatment in the hepato-biliary department. In both cases, the liver dysfunction resolved after intensive treatment with hepato-protective agents. In this report the therapeutic considerations as well as the pathogenetic possibilities are reviewed. To the best of our knowledge, this is the first description of the association observed, which is rare but may be severe and should be considered in any case of thyrotoxicosis where a liver dysfunction develops after the treatment with radioactive iodine (131)I.

Tumor necrosis factor antagonist mechanisms of action: a comprehensive review

NARCIS (Netherlands)

Tracey, Daniel; Klareskog, Lars; Sasso, Eric H.; Salfeld, Jochen G.; Tak, Paul P.

2008-01-01

During the past 30 years, elucidation of the pathogenesis of rheumatoid arthritis, Crohn's disease, psoriasis, psoriatic arthritis and ankylosing spondylitis at the cellular and molecular levels has revealed that these diseases share common mechanisms and are more closely related than was previously

It's (Zipped) in the Bag

Science.gov (United States)

Moyer, Richard H.; Everett, Susan A.

2011-01-01

Plastic baggies, especially the sealable variety, seem to be a ubiquitous part of human culture. The zipper-type seal on plastic baggies is an example of an unappreciated engineering accomplishment that is relevant to everyday life. In fact, the challenge of fastening two pieces together probably dates back to the making of tools and clothing by…

The job satisfaction of principals of previously disadvantaged schools

African Journals Online (AJOL)

The aim of this study was to identify influences on the job satisfaction of previously disadvantaged school principals in North-West Province. Evans's theory of job satisfaction, morale and motivation was useful as a conceptual framework. A mixedmethods explanatory research design was important in discovering issues with ...

75 FR 57844 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

Science.gov (United States)

2010-09-23

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39-16438. Docket No. FAA-2010-0555... (Type Certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200...

77 FR 64767 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

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2012-10-23

... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... airworthiness directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held by Israel... Certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200 airplanes...

78 FR 11567 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

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2013-02-19

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39...

76 FR 70040 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

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2011-11-10

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (type certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and... new AD: 2011-23-07 Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft...

76 FR 6525 - Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia...

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2011-02-07

... Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia Aircraft... following new AD: 2011-03-04 Cessna Aircraft Company (Type Certificate Previously Held by Columbia Aircraft... the following Cessna Aircraft Company (type certificate previously held by Columbia Aircraft...

ATLANTIC DIP: simplifying the follow-up of women with previous gestational diabetes.

LENUS (Irish Health Repository)

Noctor, E

2013-11-01

Previous gestational diabetes (GDM) is associated with a significant lifetime risk of type 2 diabetes. In this study, we assessed the performance of HbA1c and fasting plasma glucose (FPG) measurements against that of 75 g oral glucose tolerance testing (OGTT) for the follow-up screening of women with previous GDM.

Rv0004 is a new essential member of the mycobacterial DNA replication machinery.

Science.gov (United States)

Mann, Katherine M; Huang, Deborah L; Hooppaw, Anna J; Logsdon, Michelle M; Richardson, Kirill; Lee, Hark Joon; Kimmey, Jacqueline M; Aldridge, Bree B; Stallings, Christina L

2017-11-01

DNA replication is fundamental for life, yet a detailed understanding of bacterial DNA replication is limited outside the organisms Escherichia coli and Bacillus subtilis. Many bacteria, including mycobacteria, encode no identified homologs of helicase loaders or regulators of the initiator protein DnaA, despite these factors being essential for DNA replication in E. coli and B. subtilis. In this study we discover that a previously uncharacterized protein, Rv0004, from the human pathogen Mycobacterium tuberculosis is essential for bacterial viability and that depletion of Rv0004 leads to a block in cell cycle progression. Using a combination of genetic and biochemical approaches, we found that Rv0004 has a role in DNA replication, interacts with DNA and the replicative helicase DnaB, and affects DnaB-DnaA complex formation. We also identify a conserved domain in Rv0004 that is predicted to structurally resemble the N-terminal protein-protein interaction domain of DnaA. Mutation of a single conserved tryptophan within Rv0004's DnaA N-terminal-like domain leads to phenotypes similar to those observed upon Rv0004 depletion and can affect the association of Rv0004 with DnaB. In addition, using live cell imaging during depletion of Rv0004, we have uncovered a previously unappreciated role for DNA replication in coordinating mycobacterial cell division and cell size. Together, our data support that Rv0004 encodes a homolog of the recently identified DciA family of proteins found in most bacteria that lack the DnaC-DnaI helicase loaders in E. coli and B. subtilis. Therefore, the mechanisms of Rv0004 elucidated here likely apply to other DciA homologs and reveal insight into the diversity of bacterial strategies in even the most conserved biological processes.

Depression and Chronic Liver Diseases: Are There Shared Underlying Mechanisms?

Directory of Open Access Journals (Sweden)

Xiaoqin Huang

2017-05-01

Full Text Available The occurrence of depression is higher in patients with chronic liver disease (CLD than that in the general population. The mechanism described in previous studies mainly focused on inflammation and stress, which not only exists in CLD, but also emerges in common chronic diseases, leaving the specific mechanism unknown. This review was to summarize the prevalence and risk factors of depression in CLD including chronic hepatitis B, chronic hepatitis, alcoholic liver disease, and non-alcoholic fatty liver disease, and to point out the possible underlying mechanism of this potential link. Clarifying the origins of this common comorbidity (depression and CLD may provide more information to understand both diseases.

Results of monitoring at Olkiluoto in 2004. Rock mechanics

International Nuclear Information System (INIS)

Riikonen, S.

2005-09-01

This report presents Posiva Oy's results of the rock mechanical monitoring programme from the year 2004. Monitoring programme was established for long time monitoring of modifications in the bedrock during the excavation of the ONKALO underground research facility stated in Olkiluoto island. This is the first annual report where rock mechanical research work has being reported also from the monitoring point of view. Rock mechanical research work consists of both GPS measurements and microseismic measurements carried out in Olkiluoto island. Both measurements have been performed during several years even before monitoring programme was established. GPS measurements have been carried out since 1995 and microseismic network has operated since 2002. There have been no significant changes in observations when studying rock mechanical results from the year 2004 and comparing them to results from the previous years. Therefore it can be said, that so far ONKALO has barely had any effect on rock mechanics in Olkiluoto. Report has been composed from the annual reports of GPS measurements.(orig.)

VBAC Scoring: Successful vaginal delivery in previous one caesarean section in induced labour

International Nuclear Information System (INIS)

Raja, J.F.; Bangash, K.T.; Mahmud, G.

2013-01-01

Objective: To develop a scoring system for the prediction of successful vaginal birth after caesarean section, following induction of labour with intra-vaginal E2 gel (Glandin). Methods: The cross-sectional study was conducted from January 2010 to August 2011, at the Pakistan Institute of Medical Sciences in Islamabad. Trial of labour in previous one caesarean section, undergoing induction with intra-vaginal E2 gel, was attempted in 100 women. They were scored according to six variables; maternal age; gestation; indications of previous caesarean; history of vaginal birth either before or after the previous caesarean; Bishop score and body mass index. Multivariate and univariate logistic regression analysis was used to develop the scoring system. Results: Of the total, 67 (67%) women delivered vaginally, while 33 (33%) ended in repeat caesarean delivery. Among the subjects, 55 (55%) women had no history of vaginal delivery either before or after previous caesarean section; 15 (15%) had history of vaginal births both before and after the previous caesarean; while 30 (30%) had vaginal delivery only after the previous caesarean section. Rates of successful vaginal birth after caesarean increased from 38% in women having a score of 0-3 to 58% in patients scoring 4-6. Among those having a score of 7-9 and 10-12, the success rates were 71% and 86% respectively. Conclusion: Increasing scores correlated with the increasing probability of vaginal birth after caesarean undergoing induction of labour. The admission VBAC scoring system is useful in counselling women with previous caesarean for the option of induction of labour or repeat caesarean delivery. (author)

75 FR 28485 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

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2010-05-21

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39... previously held by Israel Aircraft Industries, Ltd.) Model Gulfstream 100 airplanes; and Model Astra SPX and...

Irradiation creep mechanism: an experimental perspective

International Nuclear Information System (INIS)

Garner, F.A.; Gelles, D.S.

1988-01-01

The object of this effort is to determine the mechanisms involved in radiation-induced deformation of structural materials and to apply these insights for extrapolation of available fast reactor data to fusion-relevant conditions. An extensive review was conducted of a variety of radiation-induced microstructural data, searching for microstructural records of various irradiation creep mechanisms. It was found that the stress-affected evolution of dislocation microstructure during irradiation is considerably more complex than envisioned in most theoretical modeling studies, particularly in the types of interactive feedback mechanisms operating. Reasonably conclusive evidence was found for a SIPA-type mechanism (stress-induced preferential absorption) operating on both Frank loops and network dislocations. Stress-induced preferential loop nucleation (SIPN) processes may also participate but are thought to be overshadowed by the stronger action of the SIPA-type processes operating on Frank interstitial loops. It was not possible to discern from microstructural evidence between second-order SIPA and first-order SIPA mechanisms, the latter arising from anisotropic diffusion. Evidence was presented, however, that validates the operation of stress-induced preferential unfaulting of Frank loops and stress-induced growth of previously stressed material following removal of applied stress. Dislocation glide mechanisms are also participating but the rate appears to be controlled by SIPA-type climb processes. Applied stresses were shown to generate very anisotropic distributions of Burgers vector in the irradiation-induced microstructure. 108 references, 15 figures, 1 table

SRB states and nonequilibrium statistical mechanics close to equilibrium

OpenAIRE

Gallavotti, Giovannni; Ruelle, David

1996-01-01

Nonequilibrium statistical mechanics close to equilibrium is studied using SRB states and a formula for their derivatives with respect to parameters. We write general expressions for the thermodynamic fluxes (or currents) and the transport coefficients, generalizing previous results. In this framework we give a general proof of the Onsager reciprocity relations.

Previous climatic alterations are caused by the sun

International Nuclear Information System (INIS)

Groenaas, Sigbjoern

2003-01-01

The article surveys the scientific results of previous research into the contribution of the sun to climatic alterations. The author concludes that there is evidence of eight cold periods after the last ice age and that the alterations largely were due to climate effects from the sun. However, these effects are only causing a fraction of the registered global warming. It is assumed that the human activities are contributing to the rest of the greenhouse effect

Σ--antihyperon correlations in Z0 decay and investigation of the baryon production mechanism

International Nuclear Information System (INIS)

Abbiendi, G.; Braibant, S.; Capiluppi, P.; Ciocca, C.; Cuffiani, M.; Dallavalle, M.; Fabbri, F.; Giacomelli, G.; Giacomelli, P.; Ludwig, J.; Merritt, F.S.; Rembser, C.; Ainsley, C.; Batley, R.J.; Carter, J.R.; Hill, J.C.; Tarem, S.; Verzocchi, M.; Voss, H.; Aakesson, P.F.; Barberio, E.; Burckhart, H.J.; Roeck, A. de; Wolf, E.A. de; Ferrari, P.; Frey, A.; Gruwe, M.; Hauschild, M.; Hawkings, R.; Maettig, P.; Nanjo, H.; Pater, J.R.; Pinfold, J.; Pooth, O.; Przybycien, M.; Runge, K.; Sarkisyan, E.K.G.; Schaile, O.; Scharff-Hansen, P.; Schroeder, M.; Shen, B.C.; Strom, D.; Thomson, M.A.; Vannerem, P.; Vertesi, R.; Watkins, P.M.; Watson, A.T.; Alexander, G.; Bella, G.; Etzion, E.; Grunhaus, J.; Toya, D.; Anagnostou, G.; Bell, P.J.; Charlton, D.G.; Hawkes, C.M.; Jeremie, H.; Nakamura, I.; Trigger, I.; Vossebeld, J.; Ward, C.P.; Ward, D.R.; Wermes, N.; Anderson, K.J.; Gupta, A.; McPherson, R.A.; Neal, H.A.; Pahl, C.; Smith, A.M.; Stroehmer, R.; Asai, S.; Igo-Kemenes, P.; Junk, T.R.; Karlen, D.; Kawagoe, K.; Kluth, S.; Kobel, M.; Marcellini, S.; Mes, H.; Mikenberg, G.; Mori, T.; Mutter, A.; O'Neale, S.W.; Rozen, Y.; Teuscher, R.; Trocsanyi, Z.; Wilson, J.A.; Axen, D.; Lloyd, S.L.; Martin, A.J.; Bailey, I.; Kanzaki, J.; Kawamoto, T.; Mashimo, T.; Rabbertz, K.; Sherwood, P.; Barillari, T.; Bethke, S.; Kennedy, B.W.; Oh, A.; Plane, D.E.; Schaile, A.D.; Barlow, R.J.; Duerdoth, I.P.; Ford, M.; Kupper, M.; Lillich, J.; Orito, S.; Skuja, A.; Wengler, T.; Wilson, G.W.; Bechtle, P.; Behnke, T.; Desch, K.; Hamann, M.; Heuer, R.D.; Komamiya, S.; Krogh, J. von; McKenna, J.; Menges, W.; Bell, K.W.; Brown, R.M.; Kellogg, R.G.; Bellerive, A.; Carnegie, R.K.; Jovanovic, P.; Krasznahorkay, A.; Meijers, F.; Rossi, A.M.; Benelli, G.; Campana, S.; Gary, J.W.; Giunta, M.; Hanson, G.G.; Oreglia, M.J.; Schumacher, M.; Wolf, G.; Biebel, O.; Boutemeur, M.; Dubbert, J.; Duckeck, G.; Fiedler, F.; Sachs, K.; Saeki, T.; Spano, F.; Turner-Watson, M.F.; Boeriu, O.; Fleck, I.; Herten, G.; Letts, J.; Lu, J.; Mihara, S.; Miller, D.J.; Roney, J.M.; Ueda, I.; Bock, P.; Krieger, P.; Wells, P.S.; Carter, A.A.; Levinson, L.; Mader, W.; Mohr, W.; Chang, C.Y.; Keeler, R.K.; Shears, T.G.; Vollmer, C.F.; Csilling, A.; Hajdu, C.; Horvath, D.; Dado, S.; Goldberg, J.; Harel, A.; Lafferty, G.D.; Renkel, P.; Stahl, A.; Wyatt, T.R.; Dienes, B.; Kraemer, T.; Torrence, E.; Tsur, E.; Ujvari, B.; Duchovni, E.; Gross, E.; Kuhl, T.; Lanske, D.; Lellouch, D.; Meyer, N.; Quadt, A.; Wetterling, D.; Gagnon, P.; Geich-Gimbel, C.; Kobayashi, T.; Loebinger, F.K.; Ludwig, A.; Schieck, J.; Watson, N.K.; Ishii, K.; Landsman, H.; Pilcher, J.E.; Schoerner-Sadenius, T.; Sobie, R.; Michelini, A.; Seuster, R.; Nagai, K.; Pasztor, G.; Soeldner-Rembold, S.; Tasevsky, M.

2009-01-01

Data collected around √(s)=91 GeV by the OPAL experiment at the LEP e + e - collider are used to study the mechanism of baryon formation. As the signature, the fraction of Σ - hyperons whose baryon number is compensated by the production of a anti Σ - , anti Λ or anti Ξ - antihyperon is determined. The method relies entirely on quantum number correlations of the baryons, and not rapidity correlations, making it more model independent than previous studies. Within the context of the JETSET implementation of the string hadronization model, the diquark baryon production model without the popcorn mechanism is strongly disfavored with a significance of 3.8 standard deviations including systematic uncertainties. It is shown that previous studies of the popcorn mechanism with Λanti Λ and p anti p correlations are not conclusive, if parameter uncertainties are considered. (orig.)

76 FR 1349 - Airworthiness Directives; Cessna Aircraft Company (Cessna) (Type Certificate A00003SE Previously...

Science.gov (United States)

2011-01-10

... Airworthiness Directives; Cessna Aircraft Company (Cessna) (Type Certificate A00003SE Previously Held by... Company (Type Certificate A00003SE previously held by Columbia Aircraft Manufacturing (previously The... Cessna Aircraft Company (Cessna) (Type Certificate A00003SE previously held by Columbia Aircraft...

Mechanism of action of sodium hypochlorite

Directory of Open Access Journals (Sweden)

Estrela Carlos

2002-01-01

Full Text Available The choice of an irrigating solution for use in infected root canals requires previous knowledge of the microorganisms responsible for the infectious process as well as the properties of different irrigating solutions. Complex internal anatomy, host defenses and microorganism virulence are important factors in the treatment of teeth with asymptomatic apical periodontitis. Irrigating solutions must have expressive antimicrobial action and tissue dissolution capacity. Sodium hypochlorite is the most used irrigating solution in endodontics, because its mechanism of action causes biosynthetic alterations in cellular metabolism and phospholipid destruction, formation of chloramines that interfere in cellular metabolism, oxidative action with irreversible enzymatic inactivation in bacteria, and lipid and fatty acid degradation. The aim of this work is to discuss the mechanism of action of sodium hypochlorite based on its antimicrobial and physico-chemical properties.

Chimera states in mechanical oscillator networks

DEFF Research Database (Denmark)

Martens, Erik Andreas; Thutupalli, Shashi; Fourrière, Antoine

2013-01-01

of identical oscillators, numerous theoretical studies in recent years have revealed the intriguing possibility of "chimera states," in which the symmetry of the oscillator population is broken into a synchronous part and an asynchronous part. However, a striking lack of empirical evidence raises the question...... of whether chimeras are indeed characteristic of natural systems. This calls for a palpable realization of chimera states without any fine-tuning, from which physical mechanisms underlying their emergence can be uncovered. Here, we devise a simple experiment with mechanical oscillators coupled...... in a hierarchical network to show that chimeras emerge naturally from a competition between two antagonistic synchronization patterns. We identify a wide spectrum of complex states, encompassing and extending the set of previously described chimeras. Our mathematical model shows that the self-organization observed...

Chitosan fibers with improved biological and mechanical properties for tissue engineering applications.

Science.gov (United States)

Albanna, Mohammad Z; Bou-Akl, Therese H; Blowytsky, Oksana; Walters, Henry L; Matthew, Howard W T

2013-04-01

The low mechanical properties of hydrogel materials such as chitosan hinder their broad utility for tissue engineering applications. Previous research efforts improved the mechanical properties of chitosan fiber through chemical and physical modifications; however, unfavorable toxicity effects on cells were reported. In this paper, we report the preparation of chitosan fibers with improved mechanical and biocompatibility properties. The structure-property relationships of extruded chitosan fibers were explored by varying acetic acid (AA) concentration, ammonia concentration, annealing temperature and degree of heparin crosslinking. Results showed that optimizing AA concentration to 2vol% improved fiber strength and stiffness by 2-fold. Extruding chitosan solution into 25wt% of ammonia solution reduced fiber diameters and improved fiber strength by 2-fold and stiffness by 3-fold, due to an increase in crystallinity as confirmed by XRD. Fiber annealing further reduced fiber diameter and improved fiber strength and stiffness as temperature increased. Chitosan fibers crosslinked with heparin had increased diameter but lower strength and stiffness properties and higher breaking strain values. When individual parameters were combined, further improvement in fiber mechanical properties was achieved. All mechanically improved fibers and heparin crosslinked fibers promoted valvular interstitial cells (VIC) attachment and growth over 10 day cultures. Our results demonstrate the ability to substantially improve the mechanical properties of chitosan fibers without adversely affecting their biological properties. The investigated treatments offer numerous advantages over previous physical/chemical modifications and thus are expected to expand the utility of chitosan fibers with tunable mechanical properties in various tissue engineering applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dipole mechanism of spontaneous breaking of N = 2 supersymmetry. II. Reformulation and generalization in harmonic superspace

International Nuclear Information System (INIS)

Ohta, N.

1985-01-01

After elucidating the component structure of N = 2 supersymmetric gauge theories in the harmonic superspace formalism with central charges, we reformulate our previous dipole mechanism of spontaneous breaking of N = 2 supersymmetry free from the Nambu-Goldstone-fermion difficulties in this formalism. This allows a generalization of our previous model of generating finiteness-preserving mass terms for scalar hypermultiplets; we can also obtain the gauge-fermion and scalar mass terms together with specific cubic interactions for scalar fields. The mechanism is equivalent to the so-called spurion method

Anaerobic 4-hydroxyproline utilization: Discovery of a new glycyl radical enzyme in the human gut microbiome uncovers a widespread microbial metabolic activity.

Science.gov (United States)

Huang, Yolanda Y; Martínez-Del Campo, Ana; Balskus, Emily P

2018-02-06

The discovery of enzymes responsible for previously unappreciated microbial metabolic pathways furthers our understanding of host-microbe and microbe-microbe interactions. We recently identified and characterized a new gut microbial glycyl radical enzyme (GRE) responsible for anaerobic metabolism of trans-4-hydroxy-l-proline (Hyp). Hyp dehydratase (HypD) catalyzes the removal of water from Hyp to generate Δ 1 -pyrroline-5-carboxylate (P5C). This enzyme is encoded in the genomes of a diverse set of gut anaerobes and is prevalent and abundant in healthy human stool metagenomes. Here, we discuss the roles HypD may play in different microbial metabolic pathways as well as the potential implications of this activity for colonization resistance and pathogenesis within the human gut. Finally, we present evidence of anaerobic Hyp metabolism in sediments through enrichment culturing of Hyp-degrading bacteria, highlighting the wide distribution of this pathway in anoxic environments beyond the human gut.

The bee, the flower and the electric field

Directory of Open Access Journals (Sweden)

Robert Daniel

2016-01-01

Full Text Available Insects use several different senses to forage on flowers, and detect floral cues such as color, shape, pattern, humidity and chemical volatiles. This presentation will present our discovery of a previously unappreciated sensory capacity in bumblebees (Bombus terrestris: the detection of floral electric fields. We show that these floral fields act as informational cues, and that they can be affected by the visit of naturally electrically charged bees. Like visual cues, floral electric fields exhibit variations in pattern and structure, which can be discriminated by bumblebees. We also show that such electric field information contributes to the complex array of floral cues that together improve a pollinator’s memory of floral rewards. Floral electric fields arise from complex interactions with the surrounding atmosphere, an interaction between plants and their environment that not well understood. Because floral electric fields can change within seconds, this new sensory modality - electrostatic field detection- may facilitate rapid and dynamic communication between flowers and their pollinators.

CD14 deficiency impacts glucose homeostasis in mice through altered adrenal tone.

Directory of Open Access Journals (Sweden)

James L Young

Full Text Available The toll-like receptors comprise one of the most conserved components of the innate immune system, signaling the presence of molecules of microbial origin. It has been proposed that signaling through TLR4, which requires CD14 to recognize bacterial lipopolysaccharide (LPS, may generate low-grade inflammation and thereby affect insulin sensitivity and glucose metabolism. To examine the long-term influence of partial innate immune signaling disruption on glucose homeostasis, we analyzed knockout mice deficient in CD14 backcrossed into the diabetes-prone C57BL6 background at 6 or 12 months of age. CD14-ko mice, fed either normal or high-fat diets, displayed significant glucose intolerance compared to wild type controls. They also displayed elevated norepinephrine urinary excretion and increased adrenal medullary volume, as well as an enhanced norepinephrine secretory response to insulin-induced hypoglycemia. These results point out a previously unappreciated crosstalk between innate immune- and sympathoadrenal- systems, which exerts a major long-term effect on glucose homeostasis.

Systems genetics identifies a convergent gene network for cognition and neurodevelopmental disease.

Science.gov (United States)

Johnson, Michael R; Shkura, Kirill; Langley, Sarah R; Delahaye-Duriez, Andree; Srivastava, Prashant; Hill, W David; Rackham, Owen J L; Davies, Gail; Harris, Sarah E; Moreno-Moral, Aida; Rotival, Maxime; Speed, Doug; Petrovski, Slavé; Katz, Anaïs; Hayward, Caroline; Porteous, David J; Smith, Blair H; Padmanabhan, Sandosh; Hocking, Lynne J; Starr, John M; Liewald, David C; Visconti, Alessia; Falchi, Mario; Bottolo, Leonardo; Rossetti, Tiziana; Danis, Bénédicte; Mazzuferi, Manuela; Foerch, Patrik; Grote, Alexander; Helmstaedter, Christoph; Becker, Albert J; Kaminski, Rafal M; Deary, Ian J; Petretto, Enrico

2016-02-01

Genetic determinants of cognition are poorly characterized, and their relationship to genes that confer risk for neurodevelopmental disease is unclear. Here we performed a systems-level analysis of genome-wide gene expression data to infer gene-regulatory networks conserved across species and brain regions. Two of these networks, M1 and M3, showed replicable enrichment for common genetic variants underlying healthy human cognitive abilities, including memory. Using exome sequence data from 6,871 trios, we found that M3 genes were also enriched for mutations ascertained from patients with neurodevelopmental disease generally, and intellectual disability and epileptic encephalopathy in particular. M3 consists of 150 genes whose expression is tightly developmentally regulated, but which are collectively poorly annotated for known functional pathways. These results illustrate how systems-level analyses can reveal previously unappreciated relationships between neurodevelopmental disease-associated genes in the developed human brain, and provide empirical support for a convergent gene-regulatory network influencing cognition and neurodevelopmental disease.

Commensal Microbiota Are Required for Systemic Inflammation Triggered by Necrotic Dendritic Cells

Directory of Open Access Journals (Sweden)

Jennifer A. Young

2013-06-01

Full Text Available The relationship between dendritic cells (DCs and commensal microflora in shaping systemic immune responses is not well understood. Here, we report that mice deficient for the Fas-associated death domain in DCs developed systemic inflammation associated with elevated proinflammatory cytokines and increased myeloid and B cells. These mice exhibited reduced DCs in gut-associated lymphoid tissues due to RIP3-dependent necroptosis, whereas DC functions remained intact. Induction of systemic inflammation required DC necroptosis and commensal microbiota signals that activated MyD88-dependent pathways in other cell types. Systemic inflammation was abrogated with the administration of broad-spectrum antibiotics or complete, but not DC-specific, deletion of MyD88. Thus, we have identified a previously unappreciated role for commensal microbiota in priming immune cells for inflammatory responses against necrotic cells. These studies demonstrate the impact intestinal microflora have on the immune system and their role in eliciting proper immune responses to harmful stimuli.

Localization of influenza virus proteins to nuclear dot 10 structures in influenza virus-infected cells

International Nuclear Information System (INIS)

Sato, Yoshiko; Yoshioka, Kenichi; Suzuki, Chie; Awashima, Satoshi; Hosaka, Yasuhiro; Yewdell, Jonathan; Kuroda, Kazumichi

2003-01-01

We studied influenza virus M1 protein by generating HeLa and MDCK cell lines that express M1 genetically fused to green fluorescent protein (GFP). GFP-M1 was incorporated into virions produced by influenza virus infected MDCK cells expressing the fusion protein indicating that the fusion protein is at least partially functional. Following infection of either HeLa or MDCK cells with influenza A virus (but not influenza B virus), GFP-M1 redistributes from its cytosolic/nuclear location and accumulates in nuclear dots. Immunofluorescence revealed that the nuclear dots represent nuclear dot 10 (ND10) structures. The colocalization of authentic M1, as well as NS1 and NS2 protein, with ND10 was confirmed by immunofluorescence following in situ isolation of ND10. These findings demonstrate a previously unappreciated involvement of influenza virus with ND10, a structure involved in cellular responses to immune cytokines as well as the replication of a rapidly increasing list of viruses

CD14 Deficiency Impacts Glucose Homeostasis in Mice through Altered Adrenal Tone

Science.gov (United States)

Young, James L.; Mora, Alfonso; Cerny, Anna; Czech, Michael P.; Woda, Bruce; Kurt-Jones, Evelyn A.; Finberg, Robert W.; Corvera, Silvia

2012-01-01

The toll-like receptors comprise one of the most conserved components of the innate immune system, signaling the presence of molecules of microbial origin. It has been proposed that signaling through TLR4, which requires CD14 to recognize bacterial lipopolysaccharide (LPS), may generate low-grade inflammation and thereby affect insulin sensitivity and glucose metabolism. To examine the long-term influence of partial innate immune signaling disruption on glucose homeostasis, we analyzed knockout mice deficient in CD14 backcrossed into the diabetes-prone C57BL6 background at 6 or 12 months of age. CD14-ko mice, fed either normal or high-fat diets, displayed significant glucose intolerance compared to wild type controls. They also displayed elevated norepinephrine urinary excretion and increased adrenal medullary volume, as well as an enhanced norepinephrine secretory response to insulin-induced hypoglycemia. These results point out a previously unappreciated crosstalk between innate immune- and sympathoadrenal- systems, which exerts a major long-term effect on glucose homeostasis. PMID:22253759

Macrophages Contribute to the Spermatogonial Niche in the Adult Testis

Directory of Open Access Journals (Sweden)

Tony DeFalco

2015-08-01

Full Text Available The testis produces sperm throughout the male reproductive lifespan by balancing self-renewal and differentiation of spermatogonial stem cells (SSCs. Part of the SSC niche is thought to lie outside the seminiferous tubules of the testis; however, specific interstitial components of the niche that regulate spermatogonial divisions and differentiation remain undefined. We identified distinct populations of testicular macrophages, one of which lies on the surface of seminiferous tubules, in close apposition to areas of tubules enriched for undifferentiated spermatogonia. These macrophages express spermatogonial proliferation- and differentiation-inducing factors, such as colony-stimulating factor 1 (CSF1 and enzymes involved in retinoic acid (RA biosynthesis. We show that transient depletion of macrophages leads to a disruption in spermatogonial differentiation. These findings reveal an unexpected role for macrophages in the spermatogonial niche in the testis and raise the possibility that macrophages play previously unappreciated roles in stem/progenitor cell regulation in other tissues.

A Common Origin for B-1a and B-2 Lymphocytes in Clonal Pre- Hematopoietic Stem Cells

Directory of Open Access Journals (Sweden)

Brandon K. Hadland

2017-06-01

Full Text Available Recent evidence points to the embryonic emergence of some tissue-resident innate immune cells, such as B-1a lymphocytes, prior to and independently of hematopoietic stem cells (HSCs. However, whether the full hematopoietic repertoire of embryonic HSCs initially includes these unique lineages of innate immune cells has been difficult to assess due to lack of clonal assays that identify and assess HSC precursor (pre-HSC potential. Here, by combining index sorting of single embryonic hemogenic precursors with in vitro HSC maturation and transplantation assays, we analyze emerging pre-HSCs at the single-cell level, revealing their unique stage-specific properties and clonal lineage potential. Remarkably, clonal pre-HSCs detected between E9.5 and E11.5 contribute to the complete B cell repertoire, including B-1a lymphocytes, revealing a previously unappreciated common precursor for all B cell lineages at the pre-HSC stage and a second embryonic origin for B-1a lymphocytes.

Aerosols transmit prions to immunocompetent and immunodeficient mice.

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Johannes Haybaeck

Full Text Available Prions, the agents causing transmissible spongiform encephalopathies, colonize the brain of hosts after oral, parenteral, intralingual, or even transdermal uptake. However, prions are not generally considered to be airborne. Here we report that inbred and crossbred wild-type mice, as well as tga20 transgenic mice overexpressing PrP(C, efficiently develop scrapie upon exposure to aerosolized prions. NSE-PrP transgenic mice, which express PrP(C selectively in neurons, were also susceptible to airborne prions. Aerogenic infection occurred also in mice lacking B- and T-lymphocytes, NK-cells, follicular dendritic cells or complement components. Brains of diseased mice contained PrP(Sc and transmitted scrapie when inoculated into further mice. We conclude that aerogenic exposure to prions is very efficacious and can lead to direct invasion of neural pathways without an obligatory replicative phase in lymphoid organs. This previously unappreciated risk for airborne prion transmission may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories.

Motor cortex is required for learning but not for executing a motor skill.

Science.gov (United States)

Kawai, Risa; Markman, Timothy; Poddar, Rajesh; Ko, Raymond; Fantana, Antoniu L; Dhawale, Ashesh K; Kampff, Adam R; Ölveczky, Bence P

2015-05-06

Motor cortex is widely believed to underlie the acquisition and execution of motor skills, but its contributions to these processes are not fully understood. One reason is that studies on motor skills often conflate motor cortex's established role in dexterous control with roles in learning and producing task-specific motor sequences. To dissociate these aspects, we developed a motor task for rats that trains spatiotemporally precise movement patterns without requirements for dexterity. Remarkably, motor cortex lesions had no discernible effect on the acquired skills, which were expressed in their distinct pre-lesion forms on the very first day of post-lesion training. Motor cortex lesions prior to training, however, rendered rats unable to acquire the stereotyped motor sequences required for the task. These results suggest a remarkable capacity of subcortical motor circuits to execute learned skills and a previously unappreciated role for motor cortex in "tutoring" these circuits during learning. Copyright © 2015 Elsevier Inc. All rights reserved.

Motor cortex is required for learning but not executing a motor skill

Science.gov (United States)

Kawai, Risa; Markman, Timothy; Poddar, Rajesh; Ko, Raymond; Fantana, Antoniu; Dhawale, Ashesh; Kampff, Adam R.; Ölveczky, Bence P.

2018-01-01

Motor cortex is widely believed to underlie the acquisition and execution of motor skills, yet its contributions to these processes are not fully understood. One reason is that studies on motor skills often conflate motor cortex’s established role in dexterous control with roles in learning and producing task-specific motor sequences. To dissociate these aspects, we developed a motor task for rats that trains spatiotemporally precise movement patterns without requirements for dexterity. Remarkably, motor cortex lesions had no discernible effect on the acquired skills, which were expressed in their distinct pre-lesion forms on the very first day of post-lesion training. Motor cortex lesions prior to training, however, rendered rats unable to acquire the stereotyped motor sequences required for the task. These results suggest a remarkable capacity of subcortical motor circuits to execute learned skills and a previously unappreciated role for motor cortex in ‘tutoring’ these circuits during learning. PMID:25892304

SONOGRAPHIC PREDICTION OF SCAR DEHISCENCE IN WOMEN WITH PREVIOUS CAESAREAN SECTION

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Shubhada Suhas Jajoo

2018-01-01

Full Text Available BACKGROUND Caesarean section (Sectio Caesarea is a surgical method for the completion of delivery. After various historical modifications of operative techniques, modern approach consists in the transverse dissection of the anterior wall of the uterus. The rate of vaginal birth after caesarean section was significantly reduced from year to year and the rate of repeated caesarean section is increased during the past 10 years. Evaluation of scar thickness is done by ultrasound, but it is still debatable size of thick scar that would be guiding “cut-off value” for the completion of the delivery method. To better assess the risk of uterine rupture, some authors have proposed sonographic measurement of lower uterine segment thickness near term assuming that there is an inverse correlation between LUS thickness and the risk of uterine scar defect. Therefore, this assessment for the management of women with prior CS may increase safety during labour by selecting women with the lowest risk of uterine rupture. The aim of the study is to study the diagnostic accuracy of sonographic measurements of the Lower Uterine Segment (LUS thickness near term in predicting uterine scar defects in women with prior Caesarean Section (CS. We aim to ascertain the best cut-off values for predicting uterine rupture. MATERIALS AND METHODS 100 antenatal women with history of previous one LSCS who come to attend antenatal clinic will be assessed for scar thickness by transabdominal ultrasonography and its correlation with intraoperative findings. This prospective longitudinal study was conducted for 1 year after IEC approval with inclusion criteria previous one LSCS. Exclusion criteria- 1 Previous myomectomy scar; 2 Previous 2 LSCS; 3 Previous hysterotomy scar. RESULTS Our findings indicate that there is a strong association between degree of LUS thinning measured near term and the risk of uterine scar defect at birth. In our study, optimal cut-off value for predicting

Convergent and divergent pathways decoding hierarchical additive mechanisms in treating cerebral ischemia-reperfusion injury.

Science.gov (United States)

Zhang, Ying-Ying; Li, Hai-Xia; Chen, Yin-Ying; Fang, Hong; Yu, Ya-Nan; Liu, Jun; Jing, Zhi-Wei; Wang, Zhong; Wang, Yong-Yan

2014-03-01

Cerebral ischemia is considered to be a highly complex disease resulting from the complicated interplay of multiple pathways. Disappointedly, most of the previous studies were limited to a single gene or a single pathway. The extent to which all involved pathways are translated into fusing mechanisms of a combination therapy is of fundamental importance. We report an integrative strategy to reveal the additive mechanism that a combination (BJ) of compound baicalin (BA) and jasminoidin (JA) fights against cerebral ischemia based on variation of pathways and functional communities. We identified six pathways of BJ group that shared diverse additive index from 0.09 to 1, which assembled broad cross talks from seven pathways of BA and 16 pathways of JA both at horizontal and vertical levels. Besides a total of 60 overlapping functions as a robust integration background among the three groups based on significantly differential subnetworks, additive mechanism with strong confidence by networks altered functions. These results provide strong evidence that the additive mechanism is more complex than previously appreciated, and an integrative analysis of pathways may suggest an important paradigm for revealing pharmacological mechanisms underlying drug combinations. © 2013 John Wiley & Sons Ltd.

Research on offense and defense technology for iOS kernel security mechanism

Science.gov (United States)

Chu, Sijun; Wu, Hao

2018-04-01

iOS is a strong and widely used mobile device system. It's annual profits make up about 90% of the total profits of all mobile phone brands. Though it is famous for its security, there have been many attacks on the iOS operating system, such as the Trident apt attack in 2016. So it is important to research the iOS security mechanism and understand its weaknesses and put forward targeted protection and security check framework. By studying these attacks and previous jailbreak tools, we can see that an attacker could only run a ROP code and gain kernel read and write permissions based on the ROP after exploiting kernel and user layer vulnerabilities. However, the iOS operating system is still protected by the code signing mechanism, the sandbox mechanism, and the not-writable mechanism of the system's disk area. This is far from the steady, long-lasting control that attackers expect. Before iOS 9, breaking these security mechanisms was usually done by modifying the kernel's important data structures and security mechanism code logic. However, after iOS 9, the kernel integrity protection mechanism was added to the 64-bit operating system and none of the previous methods were adapted to the new versions of iOS [1]. But this does not mean that attackers can not break through. Therefore, based on the analysis of the vulnerability of KPP security mechanism, this paper implements two possible breakthrough methods for kernel security mechanism for iOS9 and iOS10. Meanwhile, we propose a defense method based on kernel integrity detection and sensitive API call detection to defense breakthrough method mentioned above. And we make experiments to prove that this method can prevent and detect attack attempts or invaders effectively and timely.

Indirect Measurement of Energy Density of Soft PZT Ceramic Utilizing Mechanical Stress

Science.gov (United States)

Unruan, Muangjai; Unruan, Sujitra; Inkong, Yutthapong; Yimnirun, Rattikorn

2017-11-01

This paper reports on an indirect measurement of energy density of soft PZT ceramic utilizing mechanical stress. The method works analogous to the Olsen cycle and allows for a large amount of electro-mechanical energy conversion. A maximum energy density of 350 kJ/m3/cycle was found under 0-312 MPa and 1-20 kV/cm of applied mechanical stress and electric field, respectively. The obtained result is substantially higher than the results reported in previous studies of PZT materials utilizing a direct piezoelectric effect.

Transposable elements become active and mobile in the genomes of aging mammalian somatic tissues.

Science.gov (United States)

De Cecco, Marco; Criscione, Steven W; Peterson, Abigail L; Neretti, Nicola; Sedivy, John M; Kreiling, Jill A

2013-12-01

Transposable elements (TEs) were discovered by Barbara McClintock in maize and have since been found to be ubiquitous in all living organisms. Transposition is mutagenic and organisms have evolved mechanisms to repress the activity of their endogenous TEs. Transposition in somatic cells is very low, but recent evidence suggests that it may be derepressed in some cases, such as cancer development. We have found that during normal aging several families of retrotransposable elements (RTEs) start being transcribed in mouse tissues. In advanced age the expression culminates in active transposition. These processes are counteracted by calorie restriction (CR), an intervention that slows down aging. Retrotransposition is also activated in age-associated, naturally occurring cancers in the mouse. We suggest that somatic retrotransposition is a hitherto unappreciated aging process. Mobilization of RTEs is likely to be an important contributor to the progressive dysfunction of aging cells.

Hamiltonian reduction and supersymmetric mechanics with Dirac monopole

International Nuclear Information System (INIS)

Bellucci, Stefano; Nersessian, Armen; Yeranyan, Armen

2006-01-01

We apply the technique of Hamiltonian reduction for the construction of three-dimensional N=4 supersymmetric mechanics specified by the presence of a Dirac monopole. For this purpose we take the conventional N=4 supersymmetric mechanics on the four-dimensional conformally-flat spaces and perform its Hamiltonian reduction to three-dimensional system. We formulate the final system in the canonical coordinates, and present, in these terms, the explicit expressions of the Hamiltonian and supercharges. We show that, besides a magnetic monopole field, the resulting system is specified by the presence of a spin-orbit coupling term. A comparision with previous work is also carried out

Quantum mechanical signature in exclusive coherent pion production

Science.gov (United States)

Deutchman, P. A.; Buvel, R. L.; Maung, K. M.; Norbury, J. W.; Townsend, L. W.

1986-01-01

We calculate the coherent production of pions from subthreshold to relativistic energies in heavy-ion collisions using a quantum, microscopic, many-body model. For the first time, in this approach, we use harmonic oscillator wave functions to describe shell-model information. The theoretical quantum mechanical results obtained for the pion spectra represent an important improvement over our previous microscopic, many-body calculations.

Rapid fish stock depletion in previously unexploited seamounts: the ...

African Journals Online (AJOL)

Rapid fish stock depletion in previously unexploited seamounts: the case of Beryx splendens from the Sierra Leone Rise (Gulf of Guinea) ... A spectral analysis and red-noise spectra procedure (REDFIT) algorithm was used to identify the red-noise spectrum from the gaps in the observed time-series of catch per unit effort by ...

Characteristics of Acceleration and Acoustic Emission Signals from Mechanical Seals

International Nuclear Information System (INIS)

Lee, Do Hwan; Ha, Che Woong

2015-01-01

Based on these results, the applicability of acceleration signals for condition monitoring of mechanical seals is examined in the present study. Mechanical seals are used for pumps to prevent excessive leakage that might be occurred between rotational and stationary parts. The mechanical seals account for the major pump component failures. In spite of its importance, there have been few studies on condition monitoring of the components. Recently, some researchers have paid attention to the application of acoustic emission (AE) sensors for the fault detection of seals. The characteristics of acceleration and AE signals obtained from various defects are investigated. In order to prevent excessive leakage from mechanical seals, a condition monitoring technique is necessary. Based on the previous studies on AE techniques for seal monitoring, the signal characteristics from accelerometer

Characteristics of Acceleration and Acoustic Emission Signals from Mechanical Seals

Energy Technology Data Exchange (ETDEWEB)

Lee, Do Hwan; Ha, Che Woong [KHNP Central Research Institute, Daejeon (Korea, Republic of)

2015-10-15

Based on these results, the applicability of acceleration signals for condition monitoring of mechanical seals is examined in the present study. Mechanical seals are used for pumps to prevent excessive leakage that might be occurred between rotational and stationary parts. The mechanical seals account for the major pump component failures. In spite of its importance, there have been few studies on condition monitoring of the components. Recently, some researchers have paid attention to the application of acoustic emission (AE) sensors for the fault detection of seals. The characteristics of acceleration and AE signals obtained from various defects are investigated. In order to prevent excessive leakage from mechanical seals, a condition monitoring technique is necessary. Based on the previous studies on AE techniques for seal monitoring, the signal characteristics from accelerometer.

Choice of contraception after previous operative delivery at a family ...

African Journals Online (AJOL)

Choice of contraception after previous operative delivery at a family planning clinic in Northern Nigeria. Amina Mohammed‑Durosinlorun, Joel Adze, Stephen Bature, Caleb Mohammed, Matthew Taingson, Amina Abubakar, Austin Ojabo, Lydia Airede ...

Mechanical Properties Analysis of an Al-Mg Alloy Connecting Rod with Submicrometric Structure

Directory of Open Access Journals (Sweden)

Javier León

2015-07-01

Full Text Available Over these last few years, there has been a growing interest in developing mechanical components from submicrometric materials due to the significant improvement that these materials present compared to their original state. This present research work deals with the study of the mechanical properties of a connecting rod isothermally forged from different starting materials. These materials are as follows: annealed aluminum alloy (AA 5754, the same alloy previously deformed through equal channel angular pressing (ECAP and a third case where the previously ECAP-processed material is subjected to a recovery heat treatment. A comparison is made between finite volume (FV simulations and experimental tests with respect to hardness, plastic strain and forging force. Furthermore, the improvement in the mechanical properties of the connecting rod forged from predeformed material is evaluated in comparison to the connecting rod forged with annealed material. The microstructure of both cases is also compared at the end of the manufacturing process.

Mechanical properties of nuclear waste glasses

International Nuclear Information System (INIS)

Connelly, A.J.; Hand, R.J.; Bingham, P.A.; Hyatt, N.C.

2011-01-01

The mechanical properties of nuclear waste glasses are important as they will determine the degree of cracking that may occur either on cooling or following a handling accident. Recent interest in the vitrification of intermediate level radioactive waste (ILW) as well as high level radioactive waste (HLW) has led to the development of new waste glass compositions that have not previously been characterised. Therefore the mechanical properties, including Young's modulus, Poisson's ratio, hardness, indentation fracture toughness and brittleness of a series of glasses designed to safely incorporate wet ILW have been investigated. The results are presented and compared with the equivalent properties of an inactive simulant of the current UK HLW glass and other nuclear waste glasses from the literature. The higher density glasses tend to have slightly lower hardness and indentation fracture toughness values and slightly higher brittleness values, however, it is shown that the variations in mechanical properties between these different glasses are limited, are well within the range of published values for nuclear waste glasses, and that the surveyed data for all radioactive waste glasses fall within relatively narrow range.

Mechanical Properties of Magnesium-Rare Earth Alloy Systems: A Review

Directory of Open Access Journals (Sweden)

Sravya Tekumalla

2014-12-01

Full Text Available Magnesium-rare earth based alloys are increasingly being investigated due to the formation of highly stable strengthening phases, activation of additional deformation modes and improvement in mechanical properties. Several investigations have been done to study the effect of rare earths when they are alloyed to pure magnesium and other Mg alloys. In this review, the mechanical properties of the previously investigated different magnesium-rare earth based binary alloys, ternary alloys and other higher alloys with more than three alloying elements are presented.

The liquid phase oxidation of n-butane: a search for plausible mechanisms

Energy Technology Data Exchange (ETDEWEB)

Hobbs, C.C. [Celanese Ltd., TX (United States). Corpus Christi Technical Center

1998-12-31

This articles deals with an approach that has given some key information about the mechanisms of the liquid phase oxidation of butane to acetic acid. This procedure has been developed over the last 34 years; however, much of what will be discussed represents a synthesis of previous insights. Many of the observations are relatively recent and have not been previously published. In principle, this approach should be applicable to many oxidation processes. (orig.)

Effects of Mechanical Properties on Tumor Invasion: Insights from a Cellular Model

KAUST Repository

Li, YZ; Naveed, H; Liang, J; Xu, LX

2014-01-01

Understanding the regulating mechanism of tumor invasion is of crucial importance for both fundamental cancer research and clinical applications. Previous in vivo experiments have shown that invasive cancer cells dissociate from the primary tumor

Disconnection as a Mechanism for Cognitive Dysfunction in Multiple Sclerosis

Science.gov (United States)

Dineen, R. A.; Vilisaar, J.; Hlinka, J.; Bradshaw, C. M.; Morgan, P. S.; Constantinescu, C. S.; Auer, D. P.

2009-01-01

Disconnection of cognitively important processing regions by injury to the interconnecting white matter provides a potential mechanism for cognitive dysfunction in multiple sclerosis. The contribution of tract-specific white matter injury to dysfunction in different cognitive domains in patients with multiple sclerosis has not previously been…

Bonding mechanisms in spot welded three layer combinations

DEFF Research Database (Denmark)

Moghadam, Marcel; Tiedje, Niels Skat; Seyyedian Choobi, Mahsa

2016-01-01

this interface. It has been shown previously that such a joint can reach relatively high strength resulting in plug failure in tensileshear testing. Additional strength due to these bonding mechanisms is also obtained in common spot welds in the so-called corona band around the weld nugget.......The strength of a spot weld generally stems from fusion bonding of the metal layers, but other solid state bonding mechanisms also contribute to the overall strength. Metallographic analyses are presented to identify the phases formed near and across the weld interfaces and to identify...... the occurring bonding mechanisms. When welding a combination of three galvanized steel layers where one outer layer is a thin low-carbon steel it is a common challenge to obtain nugget penetration into the thin low-carbon steel. It therefore happens in real production that no nugget is formed across...

Poly-epiphyseal overgrowth: description of a previously unreported skeletal dysplasia

Energy Technology Data Exchange (ETDEWEB)

Pazzaglia, Ugo E.; Bonaspetti, Giovanni [University of Brescia, Orthopaedic Clinic, Brescia (Italy); Beluffi, Giampiero [Fondazione IRCCS Policlinico San Matteo, Department of Paediatric Radiology, Pavia (Italy); Marchi, Antonietta; Bozzola, Mauro; Savasta, Salvatore [Fondazione IRCCS Policlinico San Matteo, Paediatric Clinic, University of Pavia, Pavia (Italy)

2007-10-15

A skeletal dysplasia with previously unreported features is presented. Its evolution was characterized by growth abnormalities of bones without involvement of other organs. Advanced bone age, increased stature and irregular epiphyseal ossification with stippling of the main long bones were documented. Physeal overgrowth was massive in the left proximal humerus and femur. Furthermore, the hip joint appeared fused with an abundant mass of pathological calcific tissue extending from the femur to the ilium. Pathological epiphyses were characterized by anarchic cartilaginous proliferation with multiple ossification centres, while lamellar bone apposition and remodelling were normal. The observed bone changes were different from those in any previously reported syndrome, metabolic defect or bone dysplasia. However, they clearly indicated a defect of endochondral ossification with some resemblance to phenotypes observed in dysplasia epiphysealis hemimelica. (orig.)

Poly-epiphyseal overgrowth: description of a previously unreported skeletal dysplasia

International Nuclear Information System (INIS)

Pazzaglia, Ugo E.; Bonaspetti, Giovanni; Beluffi, Giampiero; Marchi, Antonietta; Bozzola, Mauro; Savasta, Salvatore

2007-01-01

A skeletal dysplasia with previously unreported features is presented. Its evolution was characterized by growth abnormalities of bones without involvement of other organs. Advanced bone age, increased stature and irregular epiphyseal ossification with stippling of the main long bones were documented. Physeal overgrowth was massive in the left proximal humerus and femur. Furthermore, the hip joint appeared fused with an abundant mass of pathological calcific tissue extending from the femur to the ilium. Pathological epiphyses were characterized by anarchic cartilaginous proliferation with multiple ossification centres, while lamellar bone apposition and remodelling were normal. The observed bone changes were different from those in any previously reported syndrome, metabolic defect or bone dysplasia. However, they clearly indicated a defect of endochondral ossification with some resemblance to phenotypes observed in dysplasia epiphysealis hemimelica. (orig.)

Evaluating mechanical properties and degradation of YTZP dental implants

International Nuclear Information System (INIS)

Sevilla, Pablo; Sandino, Clara; Arciniegas, Milena; Martinez-Gomis, Jordi; Peraire, Maria; Gil, Francisco Javier

2010-01-01

Lately new biomedical grade yttria stabilized zirconia (YTZP) dental implants have appeared in the implantology market. This material has better aesthetical properties than conventional titanium used for implants but long term behaviour of these new implants is not yet well known. The aim of this paper is to quantify the mechanical response of YTZP dental implants previously degraded under different time conditions and compare the toughness and fatigue strength with titanium implants. Mechanical response has been studied by means of mechanical testing following the ISO 14801 for Standards for dental implants and by finite element analysis. Accelerated hydrothermal degradation has been achieved by means of water vapour and studied by X-ray diffraction and nanoindentation tests. The results show that the degradation suffered by YTZP dental implants will not have a significant effect on the mechanical behaviour. Otherwise the fracture toughness of YTZP ceramics is still insufficient in certain implantation conditions.

Mechanisms of radical removal by SO2

DEFF Research Database (Denmark)

Rasmussen, Christian Lund; Glarborg, Peter; Marshall, Paul

2007-01-01

It is well established from experiments in premixed, laminar flames, jet-stirred reactors, flow reactors, and batch reactors that SO2 acts to catalyze hydrogen atom removal at stoichiometric and reducing conditions. However, the commonly accepted mechanism for radical removal, SO2 + H......(+M) reversible arrow HOSO(+M), HOSO + H/OH reversible arrow SO2 + H-2/H2O, has been challenged by recent theoretical and experimental results. Based on ab initio calculations for key reactions, we update the kinetic model for this chemistry and re-examine the mechanism of fuel/SO2 interactions. We find...... that the interaction of SO, with the radical pool is more complex than previously assumed, involving HOSO and SO, as well as, at high temperatures also HSO, SH, and S. The revised mechanism with a high rate constant for H + SO2 recombination and with SO + H2O, rather than SO2 + H-2, as major products of the HOSO + H...

The genesis of fluid mechanics, 1640-1780

CERN Document Server

Calero, Julián Simón

2008-01-01

Fluid Mechanics, as a scientific discipline in a modern sense, was established between the last third of the 17th century and the first half of the 18th one. This book analyses its genesis, following its evolution along two basic lines of research, which have been named the "problem of resistance" and the "problem of discharge". This approach highlights the existence of a remarkable experimental aspect in the aforementioned research lines, together with their link with problems of a practical nature, such as ballistics, hydraulics, fluid-using machines or naval theory. On the other hand, although previous studies usually present fluid mechanics from the point of view of mathematics, this is complemented here by an engineering viewpoint; gathering attempts made in the beginnings of fluid mechanics to see if the theory was capable of productive application in practical terms. This is nothing unusual in a time where the quality of knowledge and skill is measured largely by its usefulness. (c) Universidad Naciona...

The Clinical Utilisation of Respiratory Elastance Software (CURE Soft): a bedside software for real-time respiratory mechanics monitoring and mechanical ventilation management.

Science.gov (United States)

Szlavecz, Akos; Chiew, Yeong Shiong; Redmond, Daniel; Beatson, Alex; Glassenbury, Daniel; Corbett, Simon; Major, Vincent; Pretty, Christopher; Shaw, Geoffrey M; Benyo, Balazs; Desaive, Thomas; Chase, J Geoffrey

2014-09-30

Real-time patient respiratory mechanics estimation can be used to guide mechanical ventilation settings, particularly, positive end-expiratory pressure (PEEP). This work presents a software, Clinical Utilisation of Respiratory Elastance (CURE Soft), using a time-varying respiratory elastance model to offer this ability to aid in mechanical ventilation treatment. CURE Soft is a desktop application developed in JAVA. It has two modes of operation, 1) Online real-time monitoring decision support and, 2) Offline for user education purposes, auditing, or reviewing patient care. The CURE Soft has been tested in mechanically ventilated patients with respiratory failure. The clinical protocol, software testing and use of the data were approved by the New Zealand Southern Regional Ethics Committee. Using CURE Soft, patient's respiratory mechanics response to treatment and clinical protocol were monitored. Results showed that the patient's respiratory elastance (Stiffness) changed with the use of muscle relaxants, and responded differently to ventilator settings. This information can be used to guide mechanical ventilation therapy and titrate optimal ventilator PEEP. CURE Soft enables real-time calculation of model-based respiratory mechanics for mechanically ventilated patients. Results showed that the system is able to provide detailed, previously unavailable information on patient-specific respiratory mechanics and response to therapy in real-time. The additional insight available to clinicians provides the potential for improved decision-making, and thus improved patient care and outcomes.

An adaptive quantum mechanics/molecular mechanics method for the infrared spectrum of water: incorporation of the quantum effect between solute and solvent.

Science.gov (United States)

Watanabe, Hiroshi C; Banno, Misa; Sakurai, Minoru

2016-03-14

Quantum effects in solute-solvent interactions, such as the many-body effect and the dipole-induced dipole, are known to be critical factors influencing the infrared spectra of species in the liquid phase. For accurate spectrum evaluation, the surrounding solvent molecules, in addition to the solute of interest, should be treated using a quantum mechanical method. However, conventional quantum mechanics/molecular mechanics (QM/MM) methods cannot handle free QM solvent molecules during molecular dynamics (MD) simulation because of the diffusion problem. To deal with this problem, we have previously proposed an adaptive QM/MM "size-consistent multipartitioning (SCMP) method". In the present study, as the first application of the SCMP method, we demonstrate the reproduction of the infrared spectrum of liquid-phase water, and evaluate the quantum effect in comparison with conventional QM/MM simulations.

The pathogenicity of genetic variants previously associated with left ventricular non-compaction

DEFF Research Database (Denmark)

Abbasi, Yeganeh; Jabbari, Javad; Jabbari, Reza

2016-01-01

BACKGROUND: Left ventricular non-compaction (LVNC) is a rare cardiomyopathy. Many genetic variants have been associated with LVNC. However, the number of the previous LVNC-associated variants that are common in the background population remains unknown. The aim of this study was to provide...... an updated list of previously reported LVNC-associated variants with biologic description and investigate the prevalence of LVNC variants in healthy general population to find false-positive LVNC-associated variants. METHODS AND RESULTS: The Human Gene Mutation Database and PubMed were systematically...... searched to identify all previously reported LVNC-associated variants. Thereafter, the Exome Sequencing Project (ESP) and the Exome Aggregation Consortium (ExAC), that both represent the background population, was searched for all variants. Four in silico prediction tools were assessed to determine...

Mathematical methods in quantum and statistical mechanics

International Nuclear Information System (INIS)

Fishman, L.

1977-01-01

The mathematical structure and closed-form solutions pertaining to several physical problems in quantum and statistical mechanics are examined in some detail. The J-matrix method, introduced previously for s-wave scattering and based upon well-established Hilbert Space theory and related generalized integral transformation techniques, is extended to treat the lth partial wave kinetic energy and Coulomb Hamiltonians within the context of square integrable (L 2 ), Laguerre (Slater), and oscillator (Gaussian) basis sets. The theory of relaxation in statistical mechanics within the context of the theory of linear integro-differential equations of the Master Equation type and their corresponding Markov processes is examined. Several topics of a mathematical nature concerning various computational aspects of the L 2 approach to quantum scattering theory are discussed

Vibration mechanism of fuel rod in axial flow

International Nuclear Information System (INIS)

Kang, Heung Seok; Yoon, Kyung Ho; Kim, Hyung Kyu; Song, Kee Nam

1998-08-01

This is a review on the previous researches for the vibration of fuel rod induced by axial flow. The analysis methods are classified into three categories accordingly as the researchers postulate the vibration to be self-excited, forced and parametric; the self-excited mechanism by Burgreen and Quinn, the forced one by Reavis, Gorman, kanazawa, and S. Chen, and the parametric one by Y. Chen. Quinn supposed that the centrifugal force by flow exaggerated the natural bow in the cylinder, and the flexural force by it diminished the bow by turns; this interactive motion leaded cylinder to vibration. The supporters to the forced mechanism considered the forces arising from pressure perturbation within the boundary layers as vibrating sources. Y. Chen insisted that the cylinder could only be excited to vibration in resonance by the small oscillation of mean flow velocity. The previous studies were based on the simple boundary conditions such as hinged-hinged or fixed-fixed single span. Therefore, for the more accurate prediction of the fuel rod vibration in reactor, the further studies need to reflect the actual boundary conditions of the fuel rod like axial force and continuous supports by grids. (author). 25 refs

Prevalent musculoskeletal pain as a correlate of previous exposure to torture

DEFF Research Database (Denmark)

Olsen, Dorte Reff; Montgomery, Edith; Bojholm, S

2006-01-01

AIM: To research possible associations between previous exposure to specific torture techniques and prevalent pain in the head and face, back, and feet. METHODS: 221 refugees, 193 males and 28 females, previously exposed to torture in their home country, were subject to a clinical interview...... was general abuse of the whole body (OR 5.64, 95% CI 1.93-16.45). CONCLUSION: In spite of many factors being potentially co-responsible for prevalent pain, years after the torture took place it presents itself as strongly associated with specific loci of pain, with generalized effects, and with somatizing....

Payload specialist Reinhard Furrer show evidence of previous blood sampling

Science.gov (United States)

1985-01-01

Payload specialist Reinhard Furrer shows evidence of previous blood sampling while Wubbo J. Ockels, Dutch payload specialist (only partially visible), extends his right arm after a sample has been taken. Both men show bruises on their arms.

Mechanical pulping with a sequential velocity refiner- a new concept

Science.gov (United States)

C.W. McMillin

1978-01-01

In previous research with refiner mechanical pulps, a theoretical stress analysis indicated that longitudinal tracheids of Pinus taeda L. fail while under torsional stress and unwind into ribbonlike elements that provide the coherence necessary for strength development. When macerated tracheids of loblolly pine were individually stressed in torsion...

Mechanisms for cytoplasmic organization: an overview.

Science.gov (United States)

Pagliaro, L

2000-01-01

One of the basic characteristics of life is the intrinsic organization of cytoplasm, yet we know surprisingly little about the manner in which cytoplasmic macromolecules are arranged. It is clear that cytoplasm is not the homogeneous "soup" it was once envisioned to be, but a comprehensive model for cytoplasmic organization is not available in modern cell biology. The premise of this volume is that phase separation in cytoplasm may play a role in organization at the subcellular level. Other mechanisms for non-membrane-bounded intracellular organization have previously been proposed. Some of these will be reviewed in this chapter. Multiple mechanisms, involving phase separation, specific intracellular targeting, formation of macromolecular complexes, and channeling, all could well contribute to cytoplasmic organization. Temporal and spatial organization, as well as composition, are likely to be important in defining the characteristics of cytoplasm.

Analysis of previous screening examinations for patients with breast cancer

International Nuclear Information System (INIS)

Lee, Eun Hye; Cha, Joo Hee; Han, Dae Hee; Choi, Young Ho; Hwang, Ki Tae; Ryu, Dae Sik; Kwak, Jin Ho; Moon, Woo Kyung

2007-01-01

We wanted to improve the quality of subsequent screening by reviewing the previous screening of breast cancer patients. Twenty-four breast cancer patients who underwent previous screening were enrolled. All 24 took mammograms and 15 patients also took sonograms. We reviewed the screening retrospectively according to the BI-RADS criteria and we categorized the results into false negative, true negative, true positive and occult cancers. We also categorized the causes of false negative cancers into misperception, misinterpretation and technical factors and then we analyzed the attributing factors. Review of the previous screening revealed 66.7% (16/24) false negative, 25.0% (6/24) true negative, and 8.3% (2/24) true positive cancers. False negative cancers were caused by the mammogram in 56.3% (9/16) and by the sonogram in 43.7% (7/16). For the false negative cases, all of misperception were related with mammograms and this was attributed to dense breast, a lesion located at the edge of glandular tissue or the image, and findings seen on one view only. Almost all misinterpretations were related with sonograms and attributed to loose application of the final assessment. To improve the quality of breast screening, it is essential to overcome the main causes of false negative examinations, including misperception and misinterpretation. We need systematic education and strict application of final assessment categories of BI-RADS. For effective communication among physicians, it is also necessary to properly educate them about BI-RADS

Disaster Threat and The Dunning-Kruger Effect

Science.gov (United States)

2016-12-01

understand human behavior and decision making when confronted with peril has been my motivation to write this thesis. Should even a single...AVAILABILITY STATEMENT Approved for public release. Distribution is unlimited. 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) Decision making is...unappreciated wickedness can create a situation where an ostensibly illogical choice overtakes rational decision making . Sometimes, when evaluated by those

Previous utilization of service does not improve timely booking in ...

African Journals Online (AJOL)

Previous utilization of service does not improve timely booking in antenatal care: Cross sectional study ... Journal Home > Vol 24, No 3 (2010) > ... Results: Past experience on antenatal care service utilization did not come out as a predictor for ...

Radioiodine treatment of recurrent hyperthyroidism in patients previously treated for Graves' disease by subtotal thyroidectomy

DEFF Research Database (Denmark)

Vestergaard, H; Laurberg, P

1992-01-01

showed a higher sensitivity to radioiodine, with more cases of early hypothyroidism, than non-operated patients. However, after 50 months of follow-up the outcome was identical. The results indicate that frequent assessment is necessary after radioiodine treatment of previously operated patients, since......Radioiodine therapy is often employed for treatment of patients with relapse of hyperthyroidism due to Graves' disease, after previous thyroid surgery. Little is known about the outcome of this treatment compared to patients with no previous surgery. A total of 20 patients who had received surgical...... treatment for Graves' hyperthyroidism 1-46 years previously and with relapse of the hyperthyroidism, and 25 patients with hyperthyroidism due to Graves' disease and no previous thyroid surgery were treated with radioiodine, following the same protocol. Early after treatment the previously operated patients...

Penfield's prediction: a mechanism for deep brain stimulation

Directory of Open Access Journals (Sweden)

Richard W. Murrow

2014-10-01

Full Text Available (1Context: Despite its widespread use, the precise mechanism of action of Deep Brain Stimulation (DBS therapy remains unknown. The modern urgency to publish more and new data can obscure previously learned lessons by the giants who have preceded us and whose shoulders we now stand upon. Wilder Penfield extensively studied the effects of artificial electrical brain stimulation and his comments on the subject are still very relevant today. In particular, he noted two very different (and seemingly opposite effects of stimulation within the human brain. In some structures, artificial electrical stimulation has an effect which mimics ablation, while, in other structures, it produces a stimulatory effect on that tissue. (2Hypothesis:The hypothesis of this paper is fourfold. First, it proposes that some neural circuits are widely synchronized with other neural circuits, while some neural circuits are unsynchronized and operate independently. Second, it proposes that artificial high frequency electrical stimulation of a synchronized neural circuit results in an ablative effect, but artificial high frequency electrical stimulation of an unsynchronized neural circuit results in a stimulatory effect. Third, it suggests a part of the mechanism by which large scale physiologic synchronization of widely distributed independently processed information streams may occur. This may be the neural mechanism underlying Penfield’s centrencephalic system which he emphasized so many years ago. Fourth, it outlines the specific anatomic distribution of this physiologic synchronization, which Penfield has already clearly delineated as the distribution of his centrencephalic system. (3Evidence:This paper draws on a brief overview of previous theory regarding the mechanism of action of DBS and on historical, as well as widely known modern clinical data regarding the observed effects of stimulation delivered to various targets within the brain. Basic science in

Controlling Hydrogel Mechanics via Bio-Inspired Polymer-Nanoparticle Bond Dynamics.

Science.gov (United States)

Li, Qiaochu; Barrett, Devin G; Messersmith, Phillip B; Holten-Andersen, Niels

2016-01-26

Interactions between polymer molecules and inorganic nanoparticles can play a dominant role in nanocomposite material mechanics, yet control of such interfacial interaction dynamics remains a significant challenge particularly in water. This study presents insights on how to engineer hydrogel material mechanics via nanoparticle interface-controlled cross-link dynamics. Inspired by the adhesive chemistry in mussel threads, we have incorporated iron oxide nanoparticles (Fe3O4 NPs) into a catechol-modified polymer network to obtain hydrogels cross-linked via reversible metal-coordination bonds at Fe3O4 NP surfaces. Unique material mechanics result from the supra-molecular cross-link structure dynamics in the gels; in contrast to the previously reported fluid-like dynamics of transient catechol-Fe(3+) cross-links, the catechol-Fe3O4 NP structures provide solid-like yet reversible hydrogel mechanics. The structurally controlled hierarchical mechanics presented here suggest how to develop hydrogels with remote-controlled self-healing dynamics.

Personality disorders in previously detained adolescent females: a prospective study

NARCIS (Netherlands)

Krabbendam, A.; Colins, O.F.; Doreleijers, T.A.H.; van der Molen, E.; Beekman, A.T.F.; Vermeiren, R.R.J.M.

2015-01-01

This longitudinal study investigated the predictive value of trauma and mental health problems for the development of antisocial personality disorder (ASPD) and borderline personality disorder (BPD) in previously detained women. The participants were 229 detained adolescent females who were assessed

Investigation of the CH3Cl + CN(-) reaction in water: Multilevel quantum mechanics/molecular mechanics study.

Science.gov (United States)

Xu, Yulong; Zhang, Jingxue; Wang, Dunyou

2015-06-28

The CH3Cl + CN(-) reaction in water was studied using a multilevel quantum mechanics/molecular mechanics (MM) method with the multilevels, electrostatic potential, density functional theory (DFT) and coupled-cluster single double triple (CCSD(T)), for the solute region. The detailed, back-side attack SN2 reaction mechanism was mapped along the reaction pathway. The potentials of mean force were calculated under both the DFT and CCSD(T) levels for the reaction region. The CCSD(T)/MM level of theory presents a free energy activation barrier height at 20.3 kcal/mol, which agrees very well with the experiment value at 21.6 kcal/mol. The results show that the aqueous solution has a dominant role in shaping the potential of mean force. The solvation effect and the polarization effect together increase the activation barrier height by ∼11.4 kcal/mol: the solvation effect plays a major role by providing about 75% of the contribution, while polarization effect only contributes 25% to the activation barrier height. Our calculated potential of mean force under the CCSD(T)/MM also has a good agreement with the one estimated using data from previous gas-phase studies.

The long-term consequences of previous hyperthyroidism

DEFF Research Database (Denmark)

Hjelm Brandt Kristensen, Frans

2015-01-01

Thyroid hormones affect every cell in the human body, and the cardiovascular changes associated with increased levels of thyroid hormones are especially well described. As an example, short-term hyperthyroidism has positive chronotropic and inotropic effects on the heart, leading to a hyperdynamic...... with CVD, LD and DM both before and after the diagnosis of hyperthyroidism. Although the design used does not allow a stringent distinction between cause and effect, the findings indicate a possible direct association between hyperthyroidism and these morbidities, or vice versa....... vascular state. While it is biologically plausible that these changes may induce long-term consequences, the insight into morbidity as well as mortality in patients with previous hyperthyroidism is limited. The reasons for this are a combination of inadequately powered studies, varying definitions...

Multiple mechanisms of PCB neurotoxicity

Energy Technology Data Exchange (ETDEWEB)

Carpenter, D.O.; Stoner, C.T.; Lawrence, D.A. [Univ. of New York, Albany, NY (United States)] [and others

1996-12-31

Polychlorinated biphenyls (PCBs) have been implicated in cancer, but many of the symptoms in humans exposed to PCBs are related to the nervous system and behavior. We demonstrated three different direct mechanisms whereby PCBs are neurotoxic in rats. By using flow cytometry, we demonstrated that the orthosubstituted PCB congener 2,4,4{prime}, but neither TCDD nor the coplanar PCB congener 3,4,5,3{prime},4{prime}, causes rapid death of cerebellar granule cells. The ortho-substituted congener 2,4,4{prime} reduced long-term potentiation, an indicator of cognitive potential, in hippocampal brain slices, but a similar effect was observed for the coplanar congener 3,4,3{prime},4{prime}, indicating that this effect may be caused by both ortho- and coplanar congeners by mechanisms presumably not mediated via the Ah receptor. It was previously shown that some ortho-substituted PCB congeners cause a reduction in levels of the neurotransmitter dopamine, and we present in vitro and in vivo evidence that this is due to reduction of synthesis of dopamine via inhibition of the enzyme tyrosine hydroxylase. Thus, PCBs have a variety of mechanisms of primary neurotoxicity, and neurotoxicity is a characteristic of ortho-substituted, non-dioxin-like congeners as well as some coplanar congeners. The relative contribution of each of these mechanisms to the loss of cognitive function in humans exposed to PCBs remains to be determined. 42 refs., 3 figs., 1 tab.

Wave Mechanics or Wave Statistical Mechanics

International Nuclear Information System (INIS)

Qian Shangwu; Xu Laizi

2007-01-01

By comparison between equations of motion of geometrical optics and that of classical statistical mechanics, this paper finds that there should be an analogy between geometrical optics and classical statistical mechanics instead of geometrical mechanics and classical mechanics. Furthermore, by comparison between the classical limit of quantum mechanics and classical statistical mechanics, it finds that classical limit of quantum mechanics is classical statistical mechanics not classical mechanics, hence it demonstrates that quantum mechanics is a natural generalization of classical statistical mechanics instead of classical mechanics. Thence quantum mechanics in its true appearance is a wave statistical mechanics instead of a wave mechanics.

A Sociotechnical Negotiation Mechanism to Support Component Markets in Software Ecosystems

Directory of Open Access Journals (Sweden)

Rodrigo Santos

2017-12-01

Full Text Available Organizations have opened up their software platforms and reusable assets to others, including partners and third-party developers around the world, creating software ecosystems (SECOs. This perspective can contribute to minimize nontechnical barriers of software reuse in industry because it explores potential benefits from the relations among companies and stakeholders. An inhibitor is the complexity in defining value for reusable assets in a scenario where producers try to meet customers’ expectations, and vice-versa. In this paper, we present a value-based mechanism to support component negotiation and socialization processes in a reuse repository in the SECO context as an extension of the Brechó-EcoSys environment. Social resources were integrated into the mechanism in order to aid component negotiation. An evaluation of the negotiation mechanism was initially performed based on an analysis of its elements and functions against critical factors in the negotiation within a SECO, identified in a previous systematic literature review. In addition, an analysis of the social resources supporting the negotiation mechanism was performed against popular sociotechnical elements for SECOs, identified in a previous survey with experts in the field. Finally, the negotiation process and the potential support provided by sociotechnical resources were investigated through an observational study where participants were engaged in some tasks playing as consumer and producers using the sociotechnical negotiation mechanism at Brechó-EcoSys environment. We concluded that sociotechnical resources (e.g., forum and tag cloud support component producers and consumers with useful information from the SECO community.

Influence of previous experience on resistance training on reliability of one-repetition maximum test.

Science.gov (United States)

Ritti-Dias, Raphael Mendes; Avelar, Ademar; Salvador, Emanuel Péricles; Cyrino, Edilson Serpeloni

2011-05-01

The 1-repetition maximum test (1RM) has been widely used to assess maximal strength. However, to improve accuracy in assessing maximal strength, several sessions of the 1RM test are recommended. The aim of this study was to analyze the influence of previous resistance training experience on the reliability of 1RM test. Thirty men were assigned to the following 2 groups according to their previous resistance training experience: no previous resistance training experience (NOEXP) and more than 24 months of resistance training experience (EXP). All subjects performed the 1RM tests in bench press and squat in 4 sessions on distinct days. There was a significant session × group effect in bench press (F = 3.09; p reliability of the 1RM test is influenced by the subject's previous experience in resistance training. Subjects without experience in resistance training require more practice and familiarization and show greater increases in maximal strength between sessions than subjects with previous experience in resistance training.

Characterization of porosity in support of mechanical property analysis

International Nuclear Information System (INIS)

Price, R.H.; Martin, R.J. III; Boyd, P.J.

1993-01-01

The general applicability of laboratory data for engineering purposes is a prime concern for the design and licensing of a potential repository of high level nuclear waste at Yucca Mountain. In order for the results of experiments to be applicable to the repository scale, the data must be scaled to in situ size and conditions. Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sampled test. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characterizing the internal structure of the sample prior to testing is being developed and the results are being analyzed. The information obtained from this technique can help in both qualitative and quantitative interpretation of test results

Optical and mechanical anisotropy of oxide glass fibers

DEFF Research Database (Denmark)

Deubener, J.; Yue, Yuanzheng

2012-01-01

products [1], whereas stretching (frozen-in strain) results in optical and mechanical anisotropy of glass fibers, which is quantified inter alia by the specific birefringence [2]. The paper will stress the later effects by combining previous results on the structural origins of birefringence...... and anisotropic shrinkage in silica and phosphate fibers with recent studies on relaxation of optical anisotropy in E-glass fibers [3,4].......Upon fiber drawing, glass forming oxide melts are thermally quenched and mechanically stretched. High cooling rates (up to 106 K/min) of quenched glass fibres lead to higher enthalpy state of liquids, thereby, to higher fictive temperature than regular quenching (e.g. 20 K/min) of bulk glass...

Local mechanical stimulation induces components of the pathogen defense response in parsley

Science.gov (United States)

Gus-Mayer, Sabine; Naton, Beatrix; Hahlbrock, Klaus; Schmelzer, Elmon

1998-01-01

Cell suspension cultures of parsley (Petroselinum crispum) have previously been used as a suitable system for studies of the nonhost resistance response to Phytophthora sojae. In this study, we replaced the penetrating fungus by local mechanical stimulation by using a needle of the same diameter as a fungal hypha, by local application of a structurally defined fungus-derived elicitor, or by a combination of the two stimuli. Similar to the fungal infection hypha, the local mechanical stimulus alone induced the translocation of cytoplasm and nucleus to the site of stimulation, the generation of intracellular reactive oxygen intermediates (ROI), and the expression of some, but not all, elicitor-responsive genes. When the elicitor was applied locally to the cell surface without mechanical stimulation, intracellular ROI also accumulated rapidly, but morphological changes were not detected. A combination of the mechanical stimulus with simultaneous application of low doses of elicitor closely simulated early reactions to fungal infection, including cytoplasmic aggregation, nuclear migration, and ROI accumulation. By contrast, cytoplasmic rearrangements were impaired at high elicitor concentrations. Neither papilla formation nor hypersensitive cell death occurred under the conditions tested. These results suggest that mechanical stimulation by the invading fungus is responsible for the observed intracellular rearrangements and may trigger some of the previously demonstrated changes in the activity of elicitor-responsive genes, whereas chemical stimulation is required for additional biochemical processes. As yet unidentified signals may be involved in papilla formation and hypersensitive cell death. PMID:9653198

A novel mechatronic system for measuring end-point stiffness: mechanical design and preliminary tests.

Science.gov (United States)

Masia, L; Sandini, G; Morasso, P G

2011-01-01

Measuring arm stiffness is of great interest for many disciplines from biomechanics to medicine especially because modulation of impedance represents one of the main mechanism underlying control of movement and interaction with external environment. Previous works have proposed different methods to identify multijoint hand stiffness by using planar or even tridimensional haptic devices, but the associated computational burden makes them not easy to implement. We present a novel mechanism conceived for measuring multijoint planar stiffness by a single measurement and in a reduced execution time. A novel mechanical rotary device applies cyclic radial perturbation to human arm of a known displacement and the force is acquired by means of a 6-axes commercial load cell. The outcomes suggest that the system is not only reliable but allows obtaining a bi-dimensional estimation of arm stiffness in reduced amount of time and the results are comparable with those reported in previous researches. © 2011 IEEE

Tissue-selective effects of nucleolar stress and rDNA damage in developmental disorders.

Science.gov (United States)

Calo, Eliezer; Gu, Bo; Bowen, Margot E; Aryan, Fardin; Zalc, Antoine; Liang, Jialiang; Flynn, Ryan A; Swigut, Tomek; Chang, Howard Y; Attardi, Laura D; Wysocka, Joanna

2018-02-01

Many craniofacial disorders are caused by heterozygous mutations in general regulators of housekeeping cellular functions such as transcription or ribosome biogenesis. Although it is understood that many of these malformations are a consequence of defects in cranial neural crest cells, a cell type that gives rise to most of the facial structures during embryogenesis, the mechanism underlying cell-type selectivity of these defects remains largely unknown. By exploring molecular functions of DDX21, a DEAD-box RNA helicase involved in control of both RNA polymerase (Pol) I- and II-dependent transcriptional arms of ribosome biogenesis, we uncovered a previously unappreciated mechanism linking nucleolar dysfunction, ribosomal DNA (rDNA) damage, and craniofacial malformations. Here we demonstrate that genetic perturbations associated with Treacher Collins syndrome, a craniofacial disorder caused by heterozygous mutations in components of the Pol I transcriptional machinery or its cofactor TCOF1 (ref. 1), lead to relocalization of DDX21 from the nucleolus to the nucleoplasm, its loss from the chromatin targets, as well as inhibition of rRNA processing and downregulation of ribosomal protein gene transcription. These effects are cell-type-selective, cell-autonomous, and involve activation of p53 tumour-suppressor protein. We further show that cranial neural crest cells are sensitized to p53-mediated apoptosis, but blocking DDX21 loss from the nucleolus and chromatin rescues both the susceptibility to apoptosis and the craniofacial phenotypes associated with Treacher Collins syndrome. This mechanism is not restricted to cranial neural crest cells, as blood formation is also hypersensitive to loss of DDX21 functions. Accordingly, ribosomal gene perturbations associated with Diamond-Blackfan anaemia disrupt DDX21 localization. At the molecular level, we demonstrate that impaired rRNA synthesis elicits a DNA damage response, and that rDNA damage results in tissue-selective and

Modeling the mechanical properties of DNA nanostructures.

Science.gov (United States)

Arbona, Jean Michel; Aimé, Jean-Pierre; Elezgaray, Juan

2012-11-01

We discuss generalizations of a previously published coarse-grained description [Mergell et al., Phys. Rev. E 68, 021911 (2003)] of double stranded DNA (dsDNA). The model is defined at the base-pair level and includes the electrostatic repulsion between neighbor helices. We show that the model reproduces mechanical and elastic properties of several DNA nanostructures (DNA origamis). We also show that electrostatic interactions are necessary to reproduce atomic force microscopy measurements on planar DNA origamis.

Learning mechanisms to limit medication administration errors.

Science.gov (United States)

Drach-Zahavy, Anat; Pud, Dorit

2010-04-01

This paper is a report of a study conducted to identify and test the effectiveness of learning mechanisms applied by the nursing staff of hospital wards as a means of limiting medication administration errors. Since the influential report ;To Err Is Human', research has emphasized the role of team learning in reducing medication administration errors. Nevertheless, little is known about the mechanisms underlying team learning. Thirty-two hospital wards were randomly recruited. Data were collected during 2006 in Israel by a multi-method (observations, interviews and administrative data), multi-source (head nurses, bedside nurses) approach. Medication administration error was defined as any deviation from procedures, policies and/or best practices for medication administration, and was identified using semi-structured observations of nurses administering medication. Organizational learning was measured using semi-structured interviews with head nurses, and the previous year's reported medication administration errors were assessed using administrative data. The interview data revealed four learning mechanism patterns employed in an attempt to learn from medication administration errors: integrated, non-integrated, supervisory and patchy learning. Regression analysis results demonstrated that whereas the integrated pattern of learning mechanisms was associated with decreased errors, the non-integrated pattern was associated with increased errors. Supervisory and patchy learning mechanisms were not associated with errors. Superior learning mechanisms are those that represent the whole cycle of team learning, are enacted by nurses who administer medications to patients, and emphasize a system approach to data analysis instead of analysis of individual cases.

Effect of elevated substrate temperature deposition on the mechanical losses in tantala thin film coatings

Science.gov (United States)

Vajente, G.; Birney, R.; Ananyeva, A.; Angelova, S.; Asselin, R.; Baloukas, B.; Bassiri, R.; Billingsley, G.; Fejer, M. M.; Gibson, D.; Godbout, L. J.; Gustafson, E.; Heptonstall, A.; Hough, J.; MacFoy, S.; Markosyan, A.; Martin, I. W.; Martinu, L.; Murray, P. G.; Penn, S.; Roorda, S.; Rowan, S.; Schiettekatte, F.; Shink, R.; Torrie, C.; Vine, D.; Reid, S.; Adhikari, R. X.

2018-04-01

Brownian thermal noise in dielectric multilayer coatings limits the sensitivity of current and future interferometric gravitational wave detectors. In this work we explore the possibility of improving the mechanical losses of tantala, often used as the high refractive index material, by depositing it on a substrate held at elevated temperature. Promising results have been previously obtained with this technique when applied to amorphous silicon. We show that depositing tantala on a hot substrate reduced the mechanical losses of the as-deposited coating, but subsequent thermal treatments had a larger impact, as they reduced the losses to levels previously reported in the literature. We also show that the reduction in mechanical loss correlates with increased medium range order in the atomic structure of the coatings using x-ray diffraction and Raman spectroscopy. Finally, a discussion is included on our results, which shows that the elevated temperature deposition of pure tantala coatings does not appear to reduce mechanical loss in a similar way to that reported in the literature for amorphous silicon; and we suggest possible future research directions.

Single-Cell Detection of Secreted Aβ and sAPPα from Human IPSC-Derived Neurons and Astrocytes.

Science.gov (United States)

Liao, Mei-Chen; Muratore, Christina R; Gierahn, Todd M; Sullivan, Sarah E; Srikanth, Priya; De Jager, Philip L; Love, J Christopher; Young-Pearse, Tracy L

2016-02-03

Secreted factors play a central role in normal and pathological processes in every tissue in the body. The brain is composed of a highly complex milieu of different cell types and few methods exist that can identify which individual cells in a complex mixture are secreting specific analytes. By identifying which cells are responsible, we can better understand neural physiology and pathophysiology, more readily identify the underlying pathways responsible for analyte production, and ultimately use this information to guide the development of novel therapeutic strategies that target the cell types of relevance. We present here a method for detecting analytes secreted from single human induced pluripotent stem cell (iPSC)-derived neural cells and have applied the method to measure amyloid β (Aβ) and soluble amyloid precursor protein-alpha (sAPPα), analytes central to Alzheimer's disease pathogenesis. Through these studies, we have uncovered the dynamic range of secretion profiles of these analytes from single iPSC-derived neuronal and glial cells and have molecularly characterized subpopulations of these cells through immunostaining and gene expression analyses. In examining Aβ and sAPPα secretion from single cells, we were able to identify previously unappreciated complexities in the biology of APP cleavage that could not otherwise have been found by studying averaged responses over pools of cells. This technique can be readily adapted to the detection of other analytes secreted by neural cells, which would have the potential to open new perspectives into human CNS development and dysfunction. We have established a technology that, for the first time, detects secreted analytes from single human neurons and astrocytes. We examine secretion of the Alzheimer's disease-relevant factors amyloid β (Aβ) and soluble amyloid precursor protein-alpha (sAPPα) and present novel findings that could not have been observed without a single-cell analytical platform. First, we

Iodine-131 induced hepatotoxicity in previously healthy patients with Grave’s disease

Science.gov (United States)

2013-01-01

Objective To describe the association of the rare and serious complication of liver toxicity in previously healthy Grave’s disease (GD) patients after the treatment with radioactive iodine 131I (RAI). Case presentation We report the clinical, laboratory and pathologic findings of 2 cases of severe liver toxicity associated with the treatment with RAI in previously healthy patients with GD. Clinical examination and laboratory investigations excluded viral hepatitis, autoimmune hepatitis, granulomatous disease, primary biliary disease, extrahepatic biliary obstruction, and heart failure. Case 1: A previously healthy 52-years old man reportedly having a typical GD but following RAI treatment, concomitantly developed severe liver toxicity that required 1 week of treatment in hospital. Case 2: A previously healthy 34-years old woman is reported as having a typical GD but developed jaundice following RAI treatment that required several weeks of in hospital treatment in the hepato-biliary department. In both cases, the liver dysfunction resolved after intensive treatment with hepato-protective agents. In this report the therapeutic considerations as well as the pathogenetic possibilities are reviewed. Conclusion To the best of our knowledge, this is the first description of the association observed, which is rare but may be severe and should be considered in any case of thyrotoxicosis where a liver dysfunction develops after the treatment with radioactive iodine 131I. PMID:23497434

Antimetabolites in cataract surgery to prevent failure of a previous trabeculectomy.

Science.gov (United States)

Thomas, Roger E; Crichton, Andrew; Thomas, Bennett C

2014-07-28

Patients having cataract surgery have often earlier undergone a trabeculectomy for glaucoma. However, cataract surgery may be associated with failure of the previous glaucoma surgery and antimetabolites may be used with cataract surgery to prevent such failure. There is no systematic review on whether antimetabolites with cataract surgery prevent failure of a previous trabeculectomy. To assess the effects of antimetabolites with cataract surgery on functioning of a previous trabeculectomy. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2014), EMBASE (January 1980 to June 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to June 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 10 June 2014. We also searched the Science Citation Index database (July 2013) and reference lists of potentially relevant studies. Randomised controlled trials (RCTs) of antimetabolites with cataract surgery in people with a functioning trabeculectomy. Two review authors independently reviewed the titles and abstracts from the electronic searches. Two review authors independently assessed relevant full-text articles and entered data. We identified no RCTs to test the effectiveness of antimetabolites with cataract surgery in individuals with the intention of preventing failure of a previous trabeculectomy. There are no RCTs of antimetabolites with cataract surgery in people with a functioning trabeculectomy. Appropriately powered RCTs

Relativistic Quantum Mechanics

International Nuclear Information System (INIS)

Antoine, J-P

2004-01-01

The aim of relativistic quantum mechanics is to describe the finer details of the structure of atoms and molecules, where relativistic effects become nonnegligible. It is a sort of intermediate realm, between the familiar nonrelativistic quantum mechanics and fully relativistic quantum field theory, and thus it lacks the simplicity and elegance of both. Yet it is a necessary tool, mostly for quantum chemists. Pilkuhn's book offers to this audience an up-to-date survey of these methods, which is quite welcome since most previous textbooks are at least ten years old. The point of view of the author is to start immediately in the relativistic domain, following the lead of Maxwell's equations rather than classical mechanics, and thus to treat the nonrelativistic version as an approximation. Thus Chapter 1 takes off from Maxwell's equations (in the noncovariant Coulomb gauge) and gradually derives the basic aspects of Quantum Mechanics in a rather pedestrian way (states and observables, Hilbert space, operators, quantum measurement, scattering,. Chapter 2 starts with the Lorentz transformations, then continues with the Pauli spin equation and the Dirac equation and some of their applications (notably the hydrogen atom). Chapter 3 is entitled 'Quantum fields and particles', but falls short of treating quantum field theory properly: only creation/annihilation operators are considered, for a particle in a box. The emphasis is on two-electron states (the Pauli principle, the Foldy--Wouthuysen elimination of small components of Dirac spinors, Breit projection operators. Chapter 4 is devoted to scattering theory and the description of relativistic bound states. Chapter 5, finally, covers hyperfine interactions and radiative corrections. As we said above, relativistic quantum mechanics is by nature limited in scope and rather inelegant and Pilkuhn's book is no exception. The notation is often heavy (mostly noncovariant) and the mathematical level rather low. The central topic

Mechanical Modeling of a WIPP Drum Under Pressure

Energy Technology Data Exchange (ETDEWEB)

Smith, Jeffrey A. [Sandia National Laboratories, Albuquerque, NM (United States)

2014-11-25

Mechanical modeling was undertaken to support the Waste Isolation Pilot Plant (WIPP) technical assessment team (TAT) investigating the February 14th 2014 event where there was a radiological release at the WIPP. The initial goal of the modeling was to examine if a mechanical model could inform the team about the event. The intention was to have a model that could test scenarios with respect to the rate of pressurization. It was expected that the deformation and failure (inability of the drum to contain any pressure) would vary according to the pressurization rate. As the work progressed there was also interest in using the mechanical analysis of the drum to investigate what would happen if a drum pressurized when it was located under a standard waste package. Specifically, would the deformation be detectable from camera views within the room. A finite element model of a WIPP 55-gallon drum was developed that used all hex elements. Analyses were conducted using the explicit transient dynamics module of Sierra/SM to explore potential pressurization scenarios of the drum. Theses analysis show similar deformation patterns to documented pressurization tests of drums in the literature. The calculated failure pressures from previous tests documented in the literature vary from as little as 16 psi to 320 psi. In addition, previous testing documented in the literature shows drums bulging but not failing at pressures ranging from 69 to 138 psi. The analyses performed for this study found the drums failing at pressures ranging from 35 psi to 75 psi. When the drums are pressurized quickly (in 0.01 seconds) there is significant deformation to the lid. At lower pressurization rates the deformation of the lid is considerably less, yet the lids will still open from the pressure. The analyses demonstrate the influence of pressurization rate on deformation and opening pressure of the drums. Analyses conducted with a substantial mass on top of the closed drum demonstrate that the

Books average previous decade of economic misery.

Science.gov (United States)

Bentley, R Alexander; Acerbi, Alberto; Ormerod, Paul; Lampos, Vasileios

2014-01-01

For the 20(th) century since the Depression, we find a strong correlation between a 'literary misery index' derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade.

Bilateral orbital infarction and retinal detachment in a previously undiagnosed sickle cell hemoglobinopathy African child

Science.gov (United States)

Helen, Onakpoya Oluwatoyin; Ajite, K. O.; Oyelami, O. A.; Asaleye, C. M.; Adeoye, A. O.

2013-01-01

Bone infarction involving the orbit in sickle cell disease is not common. Bilateral orbital infarction in a previously undiagnosed sickle cell hemoglobinopathy has not been previously reported. In this report, we present a case of an 11-year-old previously undiagnosed sickle cell disease Nigerian girl with severe acute bilateral orbital infarction and retinal detachment to highlight that hemoglobinopathy induced orbital infarction should be considered in African children with acute onset proptosis with or without previous history of sickle cell hemoglobinopathy. PMID:23901183

Acetaminophen inhibits neuronal inflammation and protects neurons from oxidative stress

Directory of Open Access Journals (Sweden)

Grammas Paula

2009-03-01

Full Text Available Abstract Background Recent studies have demonstrated a link between the inflammatory response, increased cytokine formation, and neurodegeneration in the brain. The beneficial effects of anti-inflammatory drugs in neurodegenerative diseases, such as Alzheimer's disease (AD, have been documented. Increasing evidence suggests that acetaminophen has unappreciated anti-oxidant and anti-inflammatory properties. The objectives of this study are to determine the effects of acetaminophen on cultured brain neuronal survival and inflammatory factor expression when exposed to oxidative stress. Methods Cerebral cortical cultured neurons are pretreated with acetaminophen and then exposed to the superoxide-generating compound menadione (5 μM. Cell survival is assessed by MTT assay and inflammatory protein (tumor necrosis factor alpha, interleukin-1, macrophage inflammatory protein alpha, and RANTES release quantitated by ELISA. Expression of pro- and anti-apoptotic proteins is assessed by western blots. Results Acetaminophen has pro-survival effects on neurons in culture. Menadione, a superoxide releasing oxidant stressor, causes a significant (p Conclusion These data show that acetaminophen has anti-oxidant and anti-inflammatory effects on neurons and suggest a heretofore unappreciated therapeutic potential for this drug in neurodegenerative diseases such as AD that are characterized by oxidant and inflammatory stress.

Pleural liquid and kinetic friction coefficient of mesothelium after mechanical ventilation.

Science.gov (United States)

Bodega, Francesca; Sironi, Chiara; Porta, Cristina; Zocchi, Luciano; Agostoni, Emilio

2015-01-15

Volume and protein concentration of pleural liquid in anesthetized rabbits after 1 or 3h of mechanical ventilation, with alveolar pressure equal to atmospheric at end expiration, were compared to those occurring after spontaneous breathing. Moreover, coefficient of kinetic friction between samples of visceral and parietal pleura, obtained after spontaneous or mechanical ventilation, sliding in vitro at physiological velocity under physiological load, was determined. Volume of pleural liquid after mechanical ventilation was similar to that previously found during spontaneous ventilation. This finding is contrary to expectation of Moriondo et al. (2005), based on measurement of lymphatic and interstitial pressure. Protein concentration of pleural liquid after mechanical ventilation was also similar to that occurring after spontaneous ventilation. Coefficient of kinetic friction after mechanical ventilation was 0.023±0.001, similar to that obtained after spontaneous breathing. Copyright © 2014 Elsevier B.V. All rights reserved.

On the problem of measurement in quantum mechanics

International Nuclear Information System (INIS)

He Zuoxiu

1993-01-01

Some new developments in the theory of measurement in quantum mechanics are presented. The theory of measurement given by Von Neumann is shown to be incorrect, since the process of measurement is one of increasing entropy and cannot be derived within the scope of Schroedinger's equation. The new theory developed by Daneri, Loinger and Prosperi can avoid the difficulties previously encountered and, furthermore, can explain the EPR paradox

Previous Employment and Job Satisfaction Conditions: The Case of Regional Administration

Science.gov (United States)

Amalia, Myronaki; Nikolaos, Antonakas

2009-08-01

In the present work we study the different dimensions of satisfaction and the way of constitution of satisfaction of an important sample of the employees in the Regional administration of Crete and in their connection with the variable of the previous employment. We found statistically important differences for the components of satisfaction from the life, collaboration in and outside from the department, in the social satisfaction and the variable of the years in the service (labour group with satisfaction than the other previous employment groups. In the other hand the group with many years in the service presents bigger satisfaction than the other groups. Finally, is important to note that the sample present some interesting characteristics.

Possible mechanism for anthraquinone species diffusion in alkaline pulping

Science.gov (United States)

X.-S. Chai; J. Samp; Q.X. Hou; S.-H Yoon; J.Y. Zhu

2007-01-01

An analysis of the effectiveness of anthraquinone (AQ) in kraft-AQ pulping in terms of its mechanism of transport has been conducted. Our previous work showed that caustic solutions of wood lignin can decrease the membrane exclusion for anthraquinones, i.e., the presence of wood lignin enhances the ability of AQ to pass through a membrane when a reducing agent is...

Haemophilus influenzae type f meningitis in a previously healthy boy

DEFF Research Database (Denmark)

Ronit, Andreas; Berg, Ronan M G; Bruunsgaard, Helle

2013-01-01

Non-serotype b strains of Haemophilus influenzae are extremely rare causes of acute bacterial meningitis in immunocompetent individuals. We report a case of acute bacterial meningitis in a 14-year-old boy, who was previously healthy and had been immunised against H influenzae serotype b (Hib...

Loss of function at RAE2, a previously unidentified EPFL, is required for awnlessness in cultivated Asian rice.

Science.gov (United States)

Bessho-Uehara, Kanako; Wang, Diane R; Furuta, Tomoyuki; Minami, Anzu; Nagai, Keisuke; Gamuyao, Rico; Asano, Kenji; Angeles-Shim, Rosalyn B; Shimizu, Yoshihiro; Ayano, Madoka; Komeda, Norio; Doi, Kazuyuki; Miura, Kotaro; Toda, Yosuke; Kinoshita, Toshinori; Okuda, Satohiro; Higashiyama, Tetsuya; Nomoto, Mika; Tada, Yasuomi; Shinohara, Hidefumi; Matsubayashi, Yoshikatsu; Greenberg, Anthony; Wu, Jianzhong; Yasui, Hideshi; Yoshimura, Atsushi; Mori, Hitoshi; McCouch, Susan R; Ashikari, Motoyuki

2016-08-09

Domestication of crops based on artificial selection has contributed numerous beneficial traits for agriculture. Wild characteristics such as red pericarp and seed shattering were lost in both Asian (Oryza sativa) and African (Oryza glaberrima) cultivated rice species as a result of human selection on common genes. Awnedness, in contrast, is a trait that has been lost in both cultivated species due to selection on different sets of genes. In a previous report, we revealed that at least three loci regulate awn development in rice; however, the molecular mechanism underlying awnlessness remains unknown. Here we isolate and characterize a previously unidentified EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family member named REGULATOR OF AWN ELONGATION 2 (RAE2) and identify one of its requisite processing enzymes, SUBTILISIN-LIKE PROTEASE 1 (SLP1). The RAE2 precursor is specifically cleaved by SLP1 in the rice spikelet, where the mature RAE2 peptide subsequently induces awn elongation. Analysis of RAE2 sequence diversity identified a highly variable GC-rich region harboring multiple independent mutations underlying protein-length variation that disrupt the function of the RAE2 protein and condition the awnless phenotype in Asian rice. Cultivated African rice, on the other hand, retained the functional RAE2 allele despite its awnless phenotype. Our findings illuminate the molecular function of RAE2 in awn development and shed light on the independent domestication histories of Asian and African cultivated rice.

Induced-fit Mechanism for Prolyl Endopeptidase

Energy Technology Data Exchange (ETDEWEB)

Li, Min; Chen, Changqing; Davies, David R.; Chiu, Thang K. (NIH); (LSU); (Chinese Aca. Sci.)

2010-11-15

Prolyl peptidases cleave proteins at proline residues and are of importance for cancer, neurological function, and type II diabetes. Prolyl endopeptidase (PEP) cleaves neuropeptides and is a drug target for neuropsychiatric diseases such as post-traumatic stress disorder, depression, and schizophrenia. Previous structural analyses showing little differences between native and substrate-bound structures have suggested a lock-and-key catalytic mechanism. We now directly demonstrate from seven structures of Aeromonus punctata PEP that the mechanism is instead induced fit: the native enzyme exists in a conformationally flexible opened state with a large interdomain opening between the {beta}-propeller and {alpha}/{beta}-hydrolase domains; addition of substrate to preformed native crystals induces a large scale conformational change into a closed state with induced-fit adjustments of the active site, and inhibition of this conformational change prevents substrate binding. Absolute sequence conservation among 28 orthologs of residues at the active site and critical residues at the interdomain interface indicates that this mechanism is conserved in all PEPs. This finding has immediate implications for the use of conformationally targeted drug design to improve specificity of inhibition against this family of proline-specific serine proteases.

Effect of media composition, including gelling agents, on isolation of previously uncultured rumen bacteria.

Science.gov (United States)

Nyonyo, T; Shinkai, T; Tajima, A; Mitsumori, M

2013-01-01

The aim of this study was to develop novel anaerobic media using gellan gum for the isolation of previously uncultured rumen bacteria. Four anaerobic media, a basal liquid medium (BM) with agar (A-BM), a modified BM (MBM) with agar (A-MBM), an MBM with phytagel (P-MBM) and an MBM with gelrite (G-MBM) were used for the isolation of rumen bacteria and evaluated for the growth of previously uncultured rumen bacteria. Of the 214 isolates composed of 144 OTUs, 103 isolates (83 OTUs) were previously uncultured rumen bacteria. Most of the previously uncultured strains were obtained from A-MBM, G-MBM and P-MBM, but the predominant cultural members, isolated from each medium, differed. A-MBM and G-MBM showed significantly higher numbers of different OTUs derived from isolates than A-BM (P rumen bacteria were isolated from all media used, the ratio of previously uncultured bacteria to total isolates was increased in A-MBM, P-MBM and G-MBM. © 2012 The Society for Applied Microbiology.

Explore the reaction mechanism of the Maillard reaction: a density functional theory study.

Science.gov (United States)

Ren, Ge-Rui; Zhao, Li-Jiang; Sun, Qiang; Xie, Hu-Jun; Lei, Qun-Fang; Fang, Wen-Jun

2015-05-01

The mechanism of Maillard reaction has been investigated by means of density functional theory calculations in the gaseous phase and aqueous solution. The Maillard reaction is a cascade of consecutive and parallel reaction. In the present model system study, glucose and glycine were taken as the initial reactants. On the basis of previous experimental results, the mechanisms of Maillard reaction have been proposed, and the possibility for the formation of different compounds have been evaluated through calculating the relative energy changes for different steps of reaction under different pH conditions. Our calculations reveal that the TS3 in Amadori rearrangement reaction is the rate-determining step of Maillard reaction with the activation barriers of about 66.7 and 68.8 kcal mol(-1) in the gaseous phase and aqueous solution, respectively. The calculation results are in good agreement with previous studies and could provide insights into the reaction mechanism of Maillard reaction, since experimental evaluation of the role of intermediates in the Maillard reaction is quite complicated.

Impulsivity moderates the relationship between previous quit failure and cue-induced craving.

Science.gov (United States)

Erblich, Joel; Michalowski, Alexandra

2015-12-01

Poor inhibitory control has been shown to be an important predictor of relapse to a number of drugs, including nicotine. Indeed, smokers who exhibit higher levels of impulsivity are thought to have impaired regulation of urges to smoke, and previous research has suggested that impulsivity may moderate cue-induced cigarette cravings. To that end, we conducted a study to evaluate the interplay between failed smoking cessation, cue-induced craving, and impulsivity. Current smokers (n=151) rated their cigarette cravings before and after laboratory to exposure to smoking cues, and completed questionnaires assessing impulsivity and previous failed quit attempts. Findings indicated that shorter duration of previous failed quit attempts was related to higher cue-induced cigarette craving, especially among smokers with higher levels of impulsivity. Results underscore the importance of considering trait impulsivity as a factor in better understanding the management of cue-induced cravings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impaired insulin-stimulated nonoxidative glucose metabolism in glucose-tolerant women with previous gestational diabetes

DEFF Research Database (Denmark)

Damm, P; Vestergaard, H; Kühl, Carl Erik

1996-01-01

Our purpose was to investigate insulin sensitivity and insulin secretion in women with previous gestational diabetes.......Our purpose was to investigate insulin sensitivity and insulin secretion in women with previous gestational diabetes....

Chimera states in mechanical oscillator networks.

Science.gov (United States)

Martens, Erik Andreas; Thutupalli, Shashi; Fourrière, Antoine; Hallatschek, Oskar

2013-06-25

The synchronization of coupled oscillators is a fascinating manifestation of self-organization that nature uses to orchestrate essential processes of life, such as the beating of the heart. Although it was long thought that synchrony and disorder were mutually exclusive steady states for a network of identical oscillators, numerous theoretical studies in recent years have revealed the intriguing possibility of "chimera states," in which the symmetry of the oscillator population is broken into a synchronous part and an asynchronous part. However, a striking lack of empirical evidence raises the question of whether chimeras are indeed characteristic of natural systems. This calls for a palpable realization of chimera states without any fine-tuning, from which physical mechanisms underlying their emergence can be uncovered. Here, we devise a simple experiment with mechanical oscillators coupled in a hierarchical network to show that chimeras emerge naturally from a competition between two antagonistic synchronization patterns. We identify a wide spectrum of complex states, encompassing and extending the set of previously described chimeras. Our mathematical model shows that the self-organization observed in our experiments is controlled by elementary dynamical equations from mechanics that are ubiquitous in many natural and technological systems. The symmetry-breaking mechanism revealed by our experiments may thus be prevalent in systems exhibiting collective behavior, such as power grids, optomechanical crystals, or cells communicating via quorum sensing in microbial populations.

Mechanisms of inorganic and organometallic reactions

CERN Document Server

The purpose of this series is to provide a continuing critical review of the literature concerned with mechanistic aspects of inorganic and organo­ metallic reactions in solution, with coverage being complete in each volume. The papers discussed are selected on the basis of relevance to the elucidation of reaction mechanisms and many include results of a nonkinetic nature when useful mechanistic information can be deduced. The period of literature covered by this volume is July 1982 through December 1983, and in some instances papers not available for inclusion in the previous volume are also included. Numerical results are usually reported in the units used by the original authors, except where data from different papers are com­ pared and conversion to common units is necessary. As in previous volumes material included covers the major areas of redox processes, reactions of the nonmetallic elements, reaction of inert and labile metal complexes and the reactions of organometallic compounds. While m...

[ANTITHROMBOTIC MEDICATION IN PREGNANT WOMEN WITH PREVIOUS INTRAUTERINE GROWTH RESTRICTION].

Science.gov (United States)

Neykova, K; Dimitrova, V; Dimitrov, R; Vakrilova, L

2016-01-01

To analyze pregnancy outcome in patients who were on antithrombotic medication (AM) because of previous pregnancy with fetal intrauterine growth restriction (IUGR). The studied group (SG) included 21 pregnancies in 15 women with history of previous IUGR. The patients were on low dose aspirin (LDA) and/or low molecular weight heparin (LMWH). Pregnancy outcome was compared to the one in two more groups: 1) primary group (PG) including the previous 15 pregnancies with IUGR of the same women; 2) control group (CG) including 45 pregnancies of women matched for parity with the ones in the SG, with no history of IUGR and without medication. The SG, PG and CG were compared for the following: mean gestational age (g.a.) at birth, mean birth weight (BW), proportion of cases with early preeclampsia (PE), IUGR (total, moderate, and severe), intrauterine fetal death (IUFD), neonatal death (NND), admission to NICU, cesarean section (CS) because of chronic or acute fetal distress (FD) related to IUGR, PE or placental abruption. Student's t-test was applied to assess differences between the groups. P values < 0.05 were considered statistically significant. The differences between the SG and the PG regarding mean g. a. at delivery (33.7 and 29.8 w.g. respectively) and the proportion of babies admitted to NICU (66.7% vs. 71.4%) were not statistically significant. The mean BW in the SG (2114,7 g.) was significantly higher than in the PG (1090.8 g.). In the SG compared with the PG there were significantly less cases of IUFD (14.3% and 53.3% respectively), early PE (9.5% vs. 46.7%) moderate and severe IUGR (10.5% and 36.8% vs. 41.7% and 58.3%). Neonatal mortality in the SG (5.6%) was significantly lower than in the PG (57.1%), The proportion of CS for FD was not significantly different--53.3% in the SG and 57.1% in the PG. On the other hand, comparison between the SG and the CG demonstrated significantly lower g.a. at delivery in the SG (33.7 vs. 38 w.g.) an lower BW (2114 vs. 3094 g

A comparison of morbidity associated with placenta previa with and without previous caesarean sections

International Nuclear Information System (INIS)

Baqai, S.; Siraj, A.; Noor, N.

2018-01-01

To compare the morbidity associated with placenta previa with and without previous caesarean sections. Study Design: Retrospective comparative study. Place and Duration of Study: From March 2014 till March 2016 in the department of Obstetrics and Gynaecology at PNS Shifa hospital Karachi. Material and Methods: After the approval from hospital ethical committee, antenatal patients with singleton pregnancy of gestational age >32 weeks, in the age group of 20-40 years diagnosed to have placenta previa included in the study. All patients with twin pregnancy less than 20 years and more than 40 years of age were excluded. The records of all patients fulfilling the inclusion criteria were reviewed. Data had been collected for demographic and maternal variables, placenta previa, history of previous lower segment caesarean section (LSCS), complications associated with placenta previa and techniques used to control blood loss were recorded. Results: During the study period, 6879 patients were delivered in PNS Shifa, out of these, 2060 (29.9%) had caesarean section out of these, 47.3% patients had previous history of LSCS. Thirty three (1.6%) patients were diagnosed to have placenta previa and frequency of placenta previa was significantly higher in patients with previous history of LSCS than previous normal delivery of LSCS i.e. 22 vs. 11 (p=0.023). It was observed that the frequency of morbidly adherent placenta (MAP) and Intensive care unit (ICU) stay were significantly higher in patients with previous history of LSCS than previous history of normal delivery. Conclusion: Frequency of placenta previa was significantly higher in patients with history of LSCS. Also placenta previa remains a major risk factor for various maternal complications. (author)

Cigarette use and cardiovascular risk in chronic kidney disease: an unappreciated modifiable lifestyle risk factor.

LENUS (Irish Health Repository)

Stack, Austin G

2012-01-31

Tobacco use is a major modifiable cardiovascular risk factor in the general population and contributes to excess cardiovascular risk. Emerging evidence from large-scale observational studies suggests that continued tobacco use is also an independent cardiovascular risk factor among patients with chronic kidney disease (CKD). The benefits of smoking cessation programs on improving the heath status of patients and reducing mortality are unequivocal in the general population. Despite this, there has been little effort in pursuing tobacco cessation programs in dialysis cohorts or those with lesser degrees of kidney impairment. Most of our attention to date has focused on the development of "kidney-specific" interventions that reduce rates of renal disease progression and improve dialysis outcomes. The purpose of this current review is to describe the epidemiology of tobacco use among patients with CKD, draw attention to its negative impact on cardiovascular morbidity and mortality, and finally highlight potential strategies for successful intervention. We hope that this study heightens the importance of tobacco use in CKD, stimulates renewed interest in the barriers and challenges that exist in achieving smoking cessation, and endorses the efficacy of intervention strategies and the immeasurable benefits of quitting on cardiovascular and noncardiovascular outcomes.

Mechanical Resonators for Quantum Optomechanics Experiments at Room Temperature.

Science.gov (United States)

Norte, R A; Moura, J P; Gröblacher, S

2016-04-08

All quantum optomechanics experiments to date operate at cryogenic temperatures, imposing severe technical challenges and fundamental constraints. Here, we present a novel design of on-chip mechanical resonators which exhibit fundamental modes with frequencies f and mechanical quality factors Q_{m} sufficient to enter the optomechanical quantum regime at room temperature. We overcome previous limitations by designing ultrathin, high-stress silicon nitride (Si_{3}N_{4}) membranes, with tensile stress in the resonators' clamps close to the ultimate yield strength of the material. By patterning a photonic crystal on the SiN membranes, we observe reflectivities greater than 99%. These on-chip resonators have remarkably low mechanical dissipation, with Q_{m}∼10^{8}, while at the same time exhibiting large reflectivities. This makes them a unique platform for experiments towards the observation of massive quantum behavior at room temperature.

Complication of cesarean section: pregnancy on the cicatrix of a previous cesarean section.

Science.gov (United States)

Wang, Weimin; Long, Wenqing; Yu, Qunhuan

2002-02-01

To probe into the clinical manifestation, diagnosis, as well as treatment of pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester. Analysis of 14 patients with pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester was made after conservative treatment by drugs from January 1996 to December 1999. The 14 patients with a pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester were painless, had slight vaginal bleeding, and concurrently had increased serum beta-subunit human chorionic gonadotropin (beta-HCG). Doppler ultrasonic examination revealed an obvious enlargement of the previous cesarean section cicatrix in the uterine isthmus, and found a gestational sac or mixed mass attached to the cicatrice, with a very thin myometrium between the gestational sac and bladder walls. Among the 14 patients, 12 patients had crystalline trichosanthes injected into the cervix, mifepristone taken orally, or methotrexate in the form of intramuscular injection. Following this procedure, their serum beta-HCG dropped to normal. The other 2 patients had a total hysterectomy. Pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester is a complication of cesarean section. Early diagnosis and effective conservative treatment by drugs are instrumental in decreasing the potential occurrence of uterine rupture, which is also conducive to preserving the patient's future fertility.

National Rates of Uterine Rupture are not Associated with Rates of Previous Caesarean Delivery

DEFF Research Database (Denmark)

Colmorn, Lotte B.; Langhoff-Roos, Jens; Jakobsson, Maija

2017-01-01

% of all Nordic deliveries. Information on the comparison population was retrieved from the national medical birth registers. Incidence rate ratios by previous caesarean delivery and intended mode of delivery after caesarean were modelled using Poisson regression. RESULTS: The incidence of uterine rupture......BACKGROUND: Previous caesarean delivery and intended mode of delivery after caesarean are well-known individual risk factors for uterine rupture. We examined if different national rates of uterine rupture are associated with differences in national rates of previous caesarean delivery and intended...... was 7.8/10 000 in Finland and 4.6/10 000 in Denmark. Rates of caesarean (21.3%) and previous caesarean deliveries (11.5%) were highest in Denmark, while the rate of intended vaginal delivery after caesarean was highest in Finland (72%). National rates of uterine rupture were not associated...

A skeletal mechanism for biodiesel blend surrogates combustion

International Nuclear Information System (INIS)

An, H.; Yang, W.M.; Maghbouli, A.; Li, J.; Chua, K.J.

2014-01-01

Highlights: • A skeletal biodiesel reaction mechanism with 112 species was constructed. • The developed mechanism contains the CO, NO x and soot formation kinetics. • It was well validated against detailed reaction mechanism and experimental results. • The mechanism is suitable to simulate biodiesel, diesel and their blend fuels. - Abstract: A tri-component skeletal reaction mechanism consisting of methyl decanoate, methyl-9-decenoate, and n-heptane was developed for biodiesel combustion in diesel engine. It comprises 112 species participating in 498 reactions with the CO, NO x and soot formation mechanisms embedded. In this study, a detailed tri-component biodiesel mechanism was used as the start of mechanism reduction and the reduced mechanism was combined with a previously developed skeletal reaction mechanism for n-heptane to integrate the soot formation kinetics. A combined mechanism reduction strategy including the directed relation graph with error propagation and sensitivity analysis (DRGEPSA), peak concentration analysis, isomer lumping, unimportant reactions elimination and reaction rate adjustment methods was employed. The reduction process for biodiesel was performed over a range of initial conditions covering the pressures from 1 to 100 atm, equivalence ratios from 0.5 to 2.0 and temperatures from 700 to 1800 K, whereas for n-heptane, ignition delay predictions were compared against 17 shock tube experimental conditions. Extensive validations were performed for the developed skeletal reaction mechanism with 0-D ignition delay testing and 3-D engine simulations. The results indicated that the developed mechanism was able to accurately predict the ignition delay timings of n-heptane and biodiesel, and it could be integrated into 3-D engine simulations to predict the combustion characteristics of biodiesel. As such, the developed 112-species skeletal mechanism can accurately mimic the significant reaction pathways of the detailed reaction

Analysis of Arterial Mechanics During Head-Down-Tilt Bed Rest

Science.gov (United States)

Elliott, Morgan B.; Martin, David S.; Westby, Christian M.; Stenger, Michael B.; Platts, Steven H.

2014-01-01

Carotid, brachial, and tibial arteries reacted differently to HDTBR. Previous studies have not analyzed the mechanical properties of the human brachial or anterior tibial arteries. After slight variations during bed-rest, arterial mechanical properties and IMT returned to pre-bed rest values, with the exception of tibial stiffness and PSE, which continued to be reduced post-bed rest while the DC remained elevated. The tibial artery remodeling was probably due to decreased pressure and volume. Resulting implications for longer duration spaceflight are unclear. Arterial health may be affected by microgravity, as shown by increased thoracic aorta stiffness in other ground based simulations (Aubert).

Oxide nanoparticle EUV resists: toward understanding the mechanism of positive and negative tone patterning

KAUST Repository

Chakrabarty, Souvik; Ouyang, Christine; Krysak, Marie; Trikeriotis, Markos; Cho, Kyoungyoung; Giannelis, Emmanuel P.; Ober, Christopher K.

2013-01-01

DUV, EUV and e-beam patterning of hybrid nanoparticle photoresists have been reported previously by Ober and coworkers. The present work explores the underlying mechanism that is responsible for the dual tone patterning capability of these photoresist materials. Spectroscopic results correlated with mass loss and dissolution studies suggest a ligand exchange mechanism responsible for altering the solubility between the exposed and unexposed regions. © 2013 SPIE.

Oxide nanoparticle EUV resists: toward understanding the mechanism of positive and negative tone patterning

KAUST Repository

Chakrabarty, Souvik

2013-04-01

DUV, EUV and e-beam patterning of hybrid nanoparticle photoresists have been reported previously by Ober and coworkers. The present work explores the underlying mechanism that is responsible for the dual tone patterning capability of these photoresist materials. Spectroscopic results correlated with mass loss and dissolution studies suggest a ligand exchange mechanism responsible for altering the solubility between the exposed and unexposed regions. © 2013 SPIE.

Functional ecology of an Antarctic Dry Valley

Science.gov (United States)

Chan, Yuki; Van Nostrand, Joy D.; Zhou, Jizhong; Pointing, Stephen B.

2013-01-01

The McMurdo Dry Valleys are the largest ice-free region in Antarctica and are critically at risk from climate change. The terrestrial landscape is dominated by oligotrophic mineral soils and extensive exposed rocky surfaces where biota are largely restricted to microbial communities, although their ability to perform the majority of geobiological processes has remained largely uncharacterized. Here, we identified functional traits that drive microbial survival and community assembly, using a metagenomic approach with GeoChip-based functional gene arrays to establish metabolic capabilities in communities inhabiting soil and rock surface niches in McKelvey Valley. Major pathways in primary metabolism were identified, indicating significant plasticity in autotrophic, heterotrophic, and diazotrophic strategies supporting microbial communities. This represents a major advance beyond biodiversity surveys in that we have now identified how putative functional ecology drives microbial community assembly. Significant differences were apparent between open soil, hypolithic, chasmoendolithic, and cryptoendolithic communities. A suite of previously unappreciated Antarctic microbial stress response pathways, thermal, osmotic, and nutrient limitation responses were identified and related to environmental stressors, offering tangible clues to the mechanisms behind the enduring success of microorganisms in this seemingly inhospitable terrain. Rocky substrates exposed to larger fluctuations in environmental stress supported greater functional diversity in stress-response pathways than soils. Soils comprised a unique reservoir of genes involved in transformation of organic hydrocarbons and lignin-like degradative pathways. This has major implications for the evolutionary origin of the organisms, turnover of recalcitrant substrates in Antarctic soils, and predicting future responses to anthropogenic pollution. PMID:23671121

Deciphering hepatocellular responses to metabolic and oncogenic stress

Directory of Open Access Journals (Sweden)

Kathrina L. Marcelo

2015-08-01

Full Text Available Each cell type responds uniquely to stress and fractionally contributes to global and tissue-specific stress responses. Hepatocytes, liver macrophages (MΦ, and sinusoidal endothelial cells (SEC play functionally important and interdependent roles in adaptive processes such as obesity and tumor growth. Although these cell types demonstrate significant phenotypic and functional heterogeneity, their distinctions enabling disease-specific responses remain understudied. We developed a strategy for the simultaneous isolation and quantification of these liver cell types based on antigenic cell surface marker expression. To demonstrate the utility and applicability of this technique, we quantified liver cell-specific responses to high-fat diet (HFD or diethylnitrosamine (DEN, a liver-specific carcinogen, and found that while there was only a marginal increase in hepatocyte number, MΦ and SEC populations were quantitatively increased. Global gene expression profiling of hepatocytes, MΦ and SEC identified characteristic gene signatures that define each cell type in their distinct physiological or pathological states. Integration of hepatic gene signatures with available human obesity and liver cancer microarray data provides further insight into the cell-specific responses to metabolic or oncogenic stress. Our data reveal unique gene expression patterns that serve as molecular “fingerprints” for the cell-centric responses to pathologic stimuli in the distinct microenvironment of the liver. The technical advance highlighted in this study provides an essential resource for assessing hepatic cell-specific contributions to metabolic and oncogenic stress, information that could unveil previously unappreciated molecular mechanisms for the cellular crosstalk that underlies the continuum from metabolic disruption to obesity and ultimately hepatic cancer.

Mechanisms of antifungal drug resistance in Candida dubliniensis.

LENUS (Irish Health Repository)

Coleman, David C

2010-06-01

Candida dubliniensis was first described in 1995 and is the most closely related species to the predominant human fungal pathogen Candida albicans. C. dubliniensis is significantly less prevalent and less pathogenic than C. albicans and is primarily associated with infections in HIV-infected individuals and other immunocompromised cohorts. The population structure of C. dubliniensis consists of three well-defined major clades and is significantly less diverse than C. albicans. The majority of C. dubliniensis isolates are susceptible to antifungal drugs commonly used to treat Candida infections. To date only two major patterns of antifungal drug resistance have been identified and the molecular mechanisms of these are very similar to the resistance mechanisms that have been described previously in C. albicans. However, significant differences are evident in the predominant antifungal drug mechanisms employed by C. dubliniensis, differences that reflect its more clonal nature, its lower prevalence and characteristics of its genome, the complete sequence of which has only recently been determined.

Books Average Previous Decade of Economic Misery

Science.gov (United States)

Bentley, R. Alexander; Acerbi, Alberto; Ormerod, Paul; Lampos, Vasileios

2014-01-01

For the 20th century since the Depression, we find a strong correlation between a ‘literary misery index’ derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade. PMID:24416159

Quantum-mechanical analysis of low-gain free-electron laser oscillators

Science.gov (United States)

Fares, H.; Yamada, M.; Chiadroni, E.; Ferrario, M.

2018-05-01

In the previous classical theory of the low-gain free-electron laser (FEL) oscillators, the electron is described as a point-like particle, a delta function in the spatial space. On the other hand, in the previous quantum treatments, the electron is described as a plane wave with a single momentum state, a delta function in the momentum space. In reality, an electron must have statistical uncertainties in the position and momentum domains. Then, the electron is neither a point-like charge nor a plane wave of a single momentum. In this paper, we rephrase the theory of the low-gain FEL where the interacting electron is represented quantum mechanically by a plane wave with a finite spreading length (i.e., a wave packet). Using the concepts of the transformation of reference frames and the statistical quantum mechanics, an expression for the single-pass radiation gain is derived. The spectral broadening of the radiation is expressed in terms of the spreading length of an electron, the relaxation time characterizing the energy spread of electrons, and the interaction time. We introduce a comparison between our results and those obtained in the already known classical analyses where a good agreement between both results is shown. While the correspondence between our results and the classical results are shown, novel insights into the electron dynamics and the interaction mechanism are presented.

Antifatigue Functions and Mechanisms of Edible and Medicinal Mushrooms

Directory of Open Access Journals (Sweden)

Ping Geng

2017-01-01

Full Text Available Fatigue is the symptom of tiredness caused by physical and/or psychological stresses. As fatigue is becoming a serious problem in the modern society affecting human health, work efficiency, and quality of life, effective antifatigue remedies other than pharmacological drugs or therapies are highly needed. Mushrooms have been widely used as health foods, because of their various bioactive constituents such as polysaccharides, proteins, vitamins, minerals, and dietary fiber. This paper reviews the major findings from previous studies on the antifatigue effects, the active components of mushrooms, and the possible mechanisms. Many studies have demonstrated the antifatigue effects of edible and medicinal mushrooms. These mushrooms probably mitigate human fatigue through effects on the functional systems, including the muscular, cardiovascular, hormone, and immune system. The bioactive constituents that contribute to the antifatigue effects of mushrooms may include polysaccharides, peptides, nucleosides, phenolic compounds, and triterpenoids. Further research is still needed to identify the active ingredients and to investigate their mechanism of action on the antifatigue effects. Since most previous studies have been carried out in animal models, more human trials should be performed to verify the antifatigue function of edible and medicinal mushrooms.

Mechanical Properties of 3d Scaffolds for Bone Regeneration

Directory of Open Access Journals (Sweden)

Deividas Mizeras

2017-01-01

Full Text Available One of the biggest challenges in modern tissue engineering is a creation 3D scaffolds for bone tissue regeneration. Until now, in order to restore bone defects are used various bone substitutes (autologous and allogeneic, however, their usage is limited because is required additional surgery, possible complications, also limited their use is associated with ethical point of view. In this work we aim to determine the mechanical properties of 3D printed PLA objects having various orientation woodpile microarchitectures. In this work we chose three different 3D microarchitectures: woodpile BCC (each layer consists of parallel logs which are rotated 90 deg every next layer, woodpile FCC (every layer is additionally shifted half of the period in respect to the previous parallel log layer and a rotating woodpile 60 deg (each layer is rotated 60 deg in respect to the previous one. Compressive and bending tests were carried out with TIRAtest2300 universal testing machine. We found that 60 deg rotating woodpile geometry had the highest mechanical values which were approximately about 3 times higher than the BCC or FCC microstructures.

Mechanical alloying of a hydrogenation catalyst used for the remediation of contaminated compounds

Science.gov (United States)

Quinn, Jacqueline W. (Inventor); Clausen, Christian A. (Inventor); Geiger, Cherie L. (Inventor); Aitken, Brian S. (Inventor)

2012-01-01

A hydrogenation catalyst including a base material coated with a catalytic metal is made using mechanical milling techniques. The hydrogenation catalysts are used as an excellent catalyst for the dehalogenation of contaminated compounds and the remediation of other industrial compounds. Preferably, the hydrogenation catalyst is a bimetallic particle including zero-valent metal particles coated with a catalytic material. The mechanical milling technique is simpler and cheaper than previously used methods for producing hydrogenation catalysts.

Bees without Flowers: Before Peak Bloom, Diverse Native Bees Find Insect-Produced Honeydew Sugars.

Science.gov (United States)

Meiners, Joan M; Griswold, Terry L; Harris, David J; Ernest, S K Morgan

2017-08-01

Bee foragers respond to complex visual, olfactory, and extrasensory cues to optimize searches for floral rewards. Their abilities to detect and distinguish floral colors, shapes, volatiles, and ultraviolet signals and even gauge nectar availability from changes in floral humidity or electric fields are well studied. Bee foraging behaviors in the absence of floral cues, however, are rarely considered. We observed 42 species of wild bees visiting inconspicuous, nonflowering shrubs during early spring in a protected Mediterranean habitat. We determined experimentally that these bees were accessing sugary honeydew secretions from scale insects without the aid of standard cues. While honeydew use is known among some social Hymenoptera, its use across a diverse community of solitary bees is a novel observation. The widespread ability of native bees to locate and use unadvertised, nonfloral sugars suggests unappreciated sensory mechanisms and/or the existence of an interspecific foraging network among solitary bees that may influence how native bees cope with scarcity of floral resources and increasing environmental change.

77 FR 59242 - Extension of a Previously Approved Collection; Public Charters

Science.gov (United States)

2012-09-26

... previous notice. DATES: Comments on this notice should be received by October 26, 2012: attention OMB/OST... operator's advertising, selling or operating the charter. If the prospectus information were not collected...

Machine Learning and Quantum Mechanics

Science.gov (United States)

Chapline, George

The author has previously pointed out some similarities between selforganizing neural networks and quantum mechanics. These types of neural networks were originally conceived of as away of emulating the cognitive capabilities of the human brain. Recently extensions of these networks, collectively referred to as deep learning networks, have strengthened the connection between self-organizing neural networks and human cognitive capabilities. In this note we consider whether hardware quantum devices might be useful for emulating neural networks with human-like cognitive capabilities, or alternatively whether implementations of deep learning neural networks using conventional computers might lead to better algorithms for solving the many body Schrodinger equation.

Total hip arthroplasty after a previous pelvic osteotomy: A systematic review and meta-analysis.

Science.gov (United States)

Shigemura, T; Yamamoto, Y; Murata, Y; Sato, T; Tsuchiya, R; Wada, Y

2018-06-01

There are several reports regarding total hip arthroplasty (THA) after a previous pelvic osteotomy (PO). However, to our knowledge, until now there has been no formal systematic review and meta-analysis published to summarize the clinical results of THA after a previous PO. Therefore, we conducted a systematic review and meta-analysis of results of THA after a previous PO. We focus on these questions as follows: does a previous PO affect the results of subsequent THA, such as clinical outcomes, operative time, operative blood loss, and radiological parameters. Using PubMed, Web of Science, and Cochrane Library, we searched for relevant original papers. The pooling of data was performed using RevMan software (version 5.3, Cochrane Collaboration, Oxford, UK). A p-value50%, significant heterogeneity was assumed and a random-effects model was applied for the meta-analysis. A fixed-effects model was applied in the absence of significant heterogeneity. Eleven studies were included in this meta-analysis. The pooled results indicated that there was no significant difference in postoperative Merle D'Aubigne-Postel score (I 2 =0%, SMD=-0.15, 95% CI: -0.36 to 0.06, p=0.17), postoperative Harris hip score (I 2 =60%, SMD=-0.23, 95% CI: -0.50 to 0.05, p=0.10), operative time (I 2 =86%, SMD=0.37, 95% CI: -0.09 to 0.82, p=0.11), operative blood loss (I 2 =82%, SMD=0.23, 95% CI: -0.17 to 0.63, p=0.25), and cup abduction angle (I 2 =43%, SMD=-0.08, 95% CI: -0.25 to 0.09, p=0.38) between THA with and without a previous PO. However, cup anteversion angle of THA with a previous PO was significantly smaller than that of without a previous PO (I 2 =77%, SMD=-0.63, 95% CI: -1.13 to -0.13, p=0.01). Systematic review and meta-analysis of results of THA after a previous PO was performed. A previous PO did not affect the results of subsequent THA, except for cup anteversion. Because of the low quality evidence currently available, high-quality randomized controlled trials are required

Profound and Rapid Reduction in Body Temperature Induced by the Melanocortin Receptor Agonists

Science.gov (United States)

Xu, Yuanzhong; Kim, Eun Ran; Fan, Shengjie; Xia, Yan; Xu, Yong; Huang, Cheng; Tong, Qingchun

2014-01-01

The melanocortin receptor 4 (MC4R) plays a major role in body weight regulation and its agonist MTII has been widely used to study the role of MC4Rs in energy expenditure promotion and feeding reduction. Unexpectedly, we observed that intraperitoneal (i.p.) administration of MTII induced a rapid reduction in both body temperature and energy expenditure, which was independent of its effect on feeding and followed by a prolonged increase in energy expenditure. The rapid reduction was at least partly mediated by brain neurons since intracerebroventricular (icv) administration of alpha melanocyte-stimulating hormone, an endogenous melanocortin receptor agonist, produced a similar response. In addition, the body temperature-lowering effect of MTII was independent of the presence of MC4Rs, but in a similar fashion to the previously shown effect on body temperature by 5′AMP. Moreover, β-adrenergic receptors (β-ARs) were required for the recovery from low body temperature induced by MTII and further pharmacological studies showed that the MTII’s effect on body temperature may be partially mediated by the vasopressin V1a receptors. Collectively, our results reveal a previously unappreciated role for the melanocortin pathway in rapidly lowering body temperature. PMID:25065745

Equilibrium paradigm for field-reversed configurations and application to experiments

International Nuclear Information System (INIS)

Steinhauer, Loren C.; Intrator, T. P.

2009-01-01

Fresh insights on field-reversed configurations (FRCs) are incorporated in a new paradigm for equilibria. In particular four new or unappreciated properties are accounted for: an empirically based scrape-off layer thickness; a new, more accurate axial force balance relation; viscous force regularity at the O-point; and the broken-surface effect. The new paradigm corrects glaring defects of previous models (rigid rotor, Hill's vortex). Further, the new paradigm is simple enough to be easily used as an interpretive tool despite the limited data suite in most experiments. It is applied to the newly enhanced FRC data compendium, a database of 69 records from 15 facilities. Several important observations and corrections on the previous understanding of FRCs follow, three of which stand out. (1) The traditional axial force balance ('average-β' relation) gives an inaccurate scaling with the separatrix-to-wall radius ratio. (2) The improved equilibrium paradigm yields separatrix particle transport rates of 3-5 m 2 /s for 'best confinement' examples; this is a factor of three lower than crude 'bulk' estimates commonly used. (3) The transport compared to the Bohm rate shows a great deal of scatter (40% scatter/mean ratio), i.e., 'Bohm' is not a useful representation for transport scaling.

Profound and rapid reduction in body temperature induced by the melanocortin receptor agonists.

Science.gov (United States)

Xu, Yuanzhong; Kim, Eun Ran; Fan, Shengjie; Xia, Yan; Xu, Yong; Huang, Cheng; Tong, Qingchun

2014-08-22

The melanocortin receptor 4 (MC4R) plays a major role in body weight regulation and its agonist MTII has been widely used to study the role of MC4Rs in energy expenditure promotion and feeding reduction. Unexpectedly, we observed that intraperitoneal (i.p.) administration of MTII induced a rapid reduction in both body temperature and energy expenditure, which was independent of its effect on feeding and followed by a prolonged increase in energy expenditure. The rapid reduction was at least partly mediated by brain neurons since intracerebroventricular (icv) administration of alpha melanocyte-stimulating hormone, an endogenous melanocortin receptor agonist, produced a similar response. In addition, the body temperature-lowering effect of MTII was independent of the presence of MC4Rs, but in a similar fashion to the previously shown effect on body temperature by 5'AMP. Moreover, β-adrenergic receptors (β-ARs) were required for the recovery from low body temperature induced by MTII and further pharmacological studies showed that the MTII's effect on body temperature may be partially mediated by the vasopressin V1a receptors. Collectively, our results reveal a previously unappreciated role for the melanocortin pathway in rapidly lowering body temperature. Copyright © 2014 Elsevier Inc. All rights reserved.

Novel error propagation approach for reducing H2S/O2 reaction mechanism

International Nuclear Information System (INIS)

Selim, H.; Gupta, A.K.; Sassi, M.

2012-01-01

A reduction strategy of hydrogen sulfide/oxygen reaction mechanism is conducted to simplify the detailed mechanism. Direct relation graph and error propagation methodology (DRGEP) has been used. A novel approach of direct elementary reaction error (DERE) has been developed in this study. The developed approach allowed for further reduction of the reaction mechanism. The reduced mechanism has been compared with the detailed mechanism under different conditions to emphasize its validity. The results obtained from the resulting reduced mechanism showed good agreement with that from the detailed mechanism. However, some discrepancies have been found for some species. Hydrogen and oxygen mole fractions showed the largest discrepancy of all combustion products. The reduced mechanism was also found to be capable of tracking the changes that occur in chemical kinetics through the change in reaction conditions. A comparison on the ignition delay time obtained from the reduced mechanism and previous experimental data showed good agreement. The reduced mechanism was used to track changes in mechanistic pathways of Claus reactions with the reaction progress.

Ageing is associated with reduction of mechanically-induced activation of Smad2/3P signaling in articular cartilage

NARCIS (Netherlands)

Madej, W.M.; Caam, A.P.M. van; Blaney Davidson, E.N.; Hannink, G.J.; Buma, P.; Kraan, P.M. van der

2016-01-01

OBJECTIVE: Mechanical signals control key cellular processes in articular cartilage. Previously we have shown that mechanical compression is an important ALK5/Smad2/3P activator in cartilage explants. However, age-related changes in the cartilage are known to affect tissue mechanosensitivity and

Response to deep TMS in depressive patients with previous electroconvulsive treatment.

Science.gov (United States)

Rosenberg, Oded; Zangen, Abraham; Stryjer, Rafael; Kotler, Moshe; Dannon, Pinhas N

2010-10-01

The efficacy of transcranial magnetic stimulation (TMS) in the treatment of major depression has already been shown. Novel TMS coils allowing stimulation of deeper brain regions have recently been developed and studied. Our study is aimed at exploring the possible efficacy of deep TMS in patients with resistant depression, who previously underwent electroconvalsive therapy (ECT). Using Brainsway's deep TMS H1 coil, six patients who previously underwent ECT, were treated with 120% power of the motor threshold at a frequency of 20 Hz. Patients underwent five sessions per week, up to 4 weeks. Before the study, patients were evaluated using the Hamilton depression rating scale (HDRS, 24 items), the Hamilton anxiety scale, and the Beck depression inventory and were again evaluated after 5, 10, 15, and 20 daily treatments. Response to treatment was considered a reduction in the HDRS of at least 50%, and remission was considered a reduction of the HDRS-24 below 10 points. Two of six patients responded to the treatment with deep TMS, including one who achieved full remission. Our results suggest the possibility of a subpopulation of depressed patients who may benefit from deep TMS treatment, including patients who did not respond to ECT previously. However, the power of the study is small and similar larger samples are needed. Copyright © 2010 Elsevier Inc. All rights reserved.

Mechanisms of Evolution in High-Consequence Drug Resistance Plasmids.

Science.gov (United States)

He, Susu; Chandler, Michael; Varani, Alessandro M; Hickman, Alison B; Dekker, John P; Dyda, Fred

2016-12-06

The dissemination of resistance among bacteria has been facilitated by the fact that resistance genes are usually located on a diverse and evolving set of transmissible plasmids. However, the mechanisms generating diversity and enabling adaptation within highly successful resistance plasmids have remained obscure, despite their profound clinical significance. To understand these mechanisms, we have performed a detailed analysis of the mobilome (the entire mobile genetic element content) of a set of previously sequenced carbapenemase-producing Enterobacteriaceae (CPE) from the National Institutes of Health Clinical Center. This analysis revealed that plasmid reorganizations occurring in the natural context of colonization of human hosts were overwhelmingly driven by genetic rearrangements carried out by replicative transposons working in concert with the process of homologous recombination. A more complete understanding of the molecular mechanisms and evolutionary forces driving rearrangements in resistance plasmids may lead to fundamentally new strategies to address the problem of antibiotic resistance. The spread of antibiotic resistance among Gram-negative bacteria is a serious public health threat, as it can critically limit the types of drugs that can be used to treat infected patients. In particular, carbapenem-resistant members of the Enterobacteriaceae family are responsible for a significant and growing burden of morbidity and mortality. Here, we report on the mechanisms underlying the evolution of several plasmids carried by previously sequenced clinical Enterobacteriaceae isolates from the National Institutes of Health Clinical Center (NIH CC). Our ability to track genetic rearrangements that occurred within resistance plasmids was dependent on accurate annotation of the mobile genetic elements within the plasmids, which was greatly aided by access to long-read DNA sequencing data and knowledge of their mechanisms. Mobile genetic elements such as

Brief introduction to Lie-admissible formulations in statistical mechanics

International Nuclear Information System (INIS)

Fronteau, J.

1981-01-01

The present article is a summary of the essential ideas and results published in previous articles, the aim here being to describe the situation in a schematic way for the benefit of non-specialists. The non-truncated Liouville theorem and equation, natural introduction of Lie-admissible formulations into statistical mechanics, the notion of a statistical quasi-particle, and transition towards the notion of fine thermodynamics are discussed

Adverse obstetric outcomes in women with previous cesarean for dystocia in second stage of labor.

Science.gov (United States)

Jastrow, Nicole; Demers, Suzanne; Gauthier, Robert J; Chaillet, Nils; Brassard, Normand; Bujold, Emmanuel

2013-03-01

To evaluate obstetric outcomes in women undergoing a trial of labor (TOL) after a previous cesarean for dystocia in second stage of labor. A retrospective cohort study of women with one previous low transverse cesarean undergoing a first TOL was performed. Women with previous cesarean for dystocia in first stage and those with previous dystocia in second stage were compared with those with previous cesarean for nonrecurrent reasons (controls). Multivariable regressions analyses were performed. Of 1655 women, those with previous dystocia in second stage of labor (n = 204) had greater risks than controls (n = 880) to have an operative delivery [odds ratio (OR): 1.5; 95% confidence intervals (CI) 1.1 to 2.2], shoulder dystocia (OR: 2.9; 95% CI 1.1 to 8.0), and uterine rupture in the second stage of labor (OR: 4.9; 95% CI 1.1 to 23), and especially in case of fetal macrosomia (OR: 29.6; 95% CI 4.4 to 202). The median second stage of labor duration before uterine rupture was 2.5 hours (interquartile range: 1.5 to 3.2 hours) in these women. Previous cesarean for dystocia in the second stage of labor is associated with second-stage uterine rupture at next delivery, especially in cases of suspected fetal macrosomia and prolonged second stage of labor. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

78 FR 47546 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

Science.gov (United States)

2013-08-06

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model... Aviation Authority of Israel (CAAI), which is the aviation authority for Israel, has issued Israeli...

Mechanism of anterior-posterior polarity control in planarians

Energy Technology Data Exchange (ETDEWEB)

Lange, C.S.; Steele, V.E.

1978-01-01

The substance which inhibits brain formation in the regenerating planarian Dugesia etrusca was found to be a large molecule, at least in part protein, which electrophoreses as an electronegative moiety in pH 6.8 buffer. A model is presented, based on this finding and previous studies, which proposes an electrochemical mechanism for the control of polarity and possibly for the maintenance of tissue organization in planarians. It is proposed that a bioelectric field exists and moves the electronegative brain-inhibiting substance in a posterior direction, establishing polarity. This model explains the polarity reversal experiments using external fields and many of the previously unexplained classical planarian experiments. Data are presented demonstrating the existence, magnitude, and polarity of this bioelectric field, which is not greatly altered upon decapitation, all in accord with predictions of the model.

Virtual Learning Environment for Interactive Engagement with Advanced Quantum Mechanics

Science.gov (United States)

Pedersen, Mads Kock; Skyum, Birk; Heck, Robert; Müller, Romain; Bason, Mark; Lieberoth, Andreas; Sherson, Jacob F.

2016-06-01

A virtual learning environment can engage university students in the learning process in ways that the traditional lectures and lab formats cannot. We present our virtual learning environment StudentResearcher, which incorporates simulations, multiple-choice quizzes, video lectures, and gamification into a learning path for quantum mechanics at the advanced university level. StudentResearcher is built upon the experiences gathered from workshops with the citizen science game Quantum Moves at the high-school and university level, where the games were used extensively to illustrate the basic concepts of quantum mechanics. The first test of this new virtual learning environment was a 2014 course in advanced quantum mechanics at Aarhus University with 47 enrolled students. We found increased learning for the students who were more active on the platform independent of their previous performances.

Multiple mechanisms of phase variation of PorA in Neisseria meningitidis

NARCIS (Netherlands)

van der Ende, A.; Hopman, C. T.; Dankert, J.

2000-01-01

Previously, we reported that PorA expression in Neisseria meningitidis is modulated by variation in the length of the homopolymeric tract of guanidine residues between the -35 and -10 regions of the promoter or by deletion of porA. To reveal additional mechanisms of variation in PorA expression, the

Analytical expression for an optimised link bar mechanism for a beta-type Stirling engine

DEFF Research Database (Denmark)

Carlsen, Henrik; Bovin, Jonas Kabell

2007-01-01

The design of a mechanism for kinematic beta-type Stirling engines, where the displacer piston and the working piston share the same cylinder, is complicated. A well-known solution is the rhombic drive, but this solution depends on oil lubrication because of the gear wheels connecting the two...... counter rotating crank shafts. In a hermetically sealed Stirling engine it is an advantage to avoid oil in the crank case, making the application of the rhombic drive difficult. In this paper, another crank mechanism is presented, which has been developed for a 9 kW single cylinder engine. The new crank...... mechanism is a further development of the mechanism in a previous 9 kW engine. The crank mechanism for the beta-type Stirling engine is based on two four-link straight line mechanisms pointing up and down, respectively. The mechanism pointing upwards is connected to the working piston, while the mechanism...

Mechanical contrast in spectroscopic magnetomotive optical coherence elastography

International Nuclear Information System (INIS)

Ahmad, Adeel; Huang, Pin-Chieh; Sobh, Nahil A; Pande, Paritosh; Kim, Jongsik; Boppart, Stephen A

2015-01-01

The viscoelastic properties of tissues are altered during pathogenesis of numerous diseases and can therefore be a useful indicator of disease status and progression. Several elastography studies have utilized the mechanical frequency response and the resonance frequencies of tissue samples to characterize their mechanical properties. However, using the resonance frequency as a source of mechanical contrast in heterogeneous samples is complicated because it not only depends on the viscoelastic properties but also on the geometry and boundary conditions. In an elastography technique called magnetomotive optical coherence elastography (MM-OCE), the controlled movement of magnetic nanoparticles (MNPs) within the sample is used to obtain the mechanical properties. Previous demonstrations of MM-OCE have typically used point measurements in elastically homogeneous samples assuming a uniform concentration of MNPs. In this study, we evaluate the feasibility of generating MM-OCE elastograms in heterogeneous samples based on a spectroscopic approach which involves measuring the magnetomotive response at different excitation frequencies. Biological tissues and tissue-mimicking phantoms with two elastically distinct regions placed in side-by-side and bilayer configurations were used for the experiments, and finite element method simulations were used to validate the experimental results. (paper)

A bistable mechanism for chord extension morphing rotors

Science.gov (United States)

Johnson, Terrence; Frecker, Mary; Gandhi, Farhan

2009-03-01

Research efforts have shown that helicopter rotor blade morphing is an effective means to improve flight performance. Previous example of rotor blade morphing include using smart-materials for trailing deflection and rotor blade twist and tip twist, the development of a comfortable airfoil using compliant mechanisms, the use of a Gurney flap for air-flow deflection and centrifugal force actuated device to increase the span of the blade. In this paper we explore the use of a bistable mechanism for rotor morphing, specifically, blade chord extension using a bistable arc. Increasing the chord of the rotor blade is expected to generate more lift-load and improve helicopter performance. Bistable or "snap through" mechanisms have multiple stable equilibrium states and are a novel way to achieve large actuation output stroke. Bistable mechanisms do not require energy input to maintain a stable equilibrium state as both states do not require locking. In this work, we introduce a methodology for the design of bistable arcs for chord morphing using the finite element analysis and pseudo-rigid body model, to study the effect of different arc types, applied loads and rigidity on arc performance.

Mechanisms of buffer therapy resistance.

Science.gov (United States)

Bailey, Kate M; Wojtkowiak, Jonathan W; Cornnell, Heather H; Ribeiro, Maria C; Balagurunathan, Yoganand; Hashim, Arig Ibrahim; Gillies, Robert J

2014-04-01

Many studies have shown that the acidity of solid tumors contributes to local invasion and metastasis. Oral pH buffers can specifically neutralize the acidic pH of tumors and reduce the incidence of local invasion and metastatic formation in multiple murine models. However, this effect is not universal as we have previously observed that metastasis is not inhibited by buffers in some tumor models, regardless of buffer used. B16-F10 (murine melanoma), LL/2 (murine lung) and HCT116 (human colon) tumors are resistant to treatment with lysine buffer therapy, whereas metastasis is potently inhibited by lysine buffers in MDA-MB-231 (human breast) and PC3M (human prostate) tumors. In the current work, we confirmed that sensitive cells utilized a pH-dependent mechanism for successful metastasis supported by a highly glycolytic phenotype that acidifies the local tumor microenvironment resulting in morphological changes. In contrast, buffer-resistant cell lines exhibited a pH-independent metastatic mechanism involving constitutive secretion of matrix degrading proteases without elevated glycolysis. These results have identified two distinct mechanisms of experimental metastasis, one of which is pH-dependent (buffer therapy sensitive cells) and one which is pH-independent (buffer therapy resistant cells). Further characterization of these models has potential for therapeutic benefit. Copyright © 2014 Neoplasia Press, Inc. Published by Elsevier Inc. All rights reserved.

Quantum mechanical noise in coherent-state and squeezed-state Michelson interferometers

International Nuclear Information System (INIS)

Assaf, Ohad; Ben-Aryeh, Yacob

2002-01-01

In the present study we extend and generalize previous results for coherent-state and squeezed-state Michelson interferometer quantum mechanical uncertainties (or fluctuations), which are commonly referred to as 'quantum noise'. The calculation of photon counting (PC) fluctuations in the squeezed-state interferometer is extended to fourth-order correlation functions used as the measured signal. We also generalize a 'unified model' for treating both PC and radiation pressure fluctuations in the coherent-state interferometer, by using mathematical methods which apply to Kerr-type interactions. The results are more general than those reported previously in two ways. First, we obtain exact expressions, which lead to previous results under certain approximations. Second, we deal with cases in which the responses of the two mirrors to radiation pressure are not equal

Use of the mechanical leech for successful zone I replantation.

Science.gov (United States)

Kim, Sang Wha; Han, Hyun Ho; Jung, Sung-No

2014-01-01

Replantation of zone I finger injuries remains a challenge, particularly if the fingertip was previously scarred or atrophied, which makes it difficult to secure a suitable vein at the amputation site. In cases of artery-only anastomosis, we propose using a mechanical leech technique to maintain sufficient venous outflow until the internal circulation regenerates. We applied this procedure to eight patients who had zone 1 amputations without veins that were suitable for anastomosis. Emergent surgery was performed and an artery-only anastomosis was created. As there were no veins available, we cut a branch of the central artery and anastomosed it with a 24-gauge angioneedle, which served as a conduit for venous drainage. The overall survival rate for zone I replantation using mechanical leech was 87.5% and the average time to maintain the mechanical leech was 5 days. The mechanical leech technique may serve as an alternative option for the management of venous congestion when no viable veins are available.

Use of the Mechanical Leech for Successful Zone I Replantation

Directory of Open Access Journals (Sweden)

Sang Wha Kim

2014-01-01

Full Text Available Replantation of zone I finger injuries remains a challenge, particularly if the fingertip was previously scarred or atrophied, which makes it difficult to secure a suitable vein at the amputation site. In cases of artery-only anastomosis, we propose using a mechanical leech technique to maintain sufficient venous outflow until the internal circulation regenerates. We applied this procedure to eight patients who had zone 1 amputations without veins that were suitable for anastomosis. Emergent surgery was performed and an artery-only anastomosis was created. As there were no veins available, we cut a branch of the central artery and anastomosed it with a 24-gauge angioneedle, which served as a conduit for venous drainage. The overall survival rate for zone I replantation using mechanical leech was 87.5% and the average time to maintain the mechanical leech was 5 days. The mechanical leech technique may serve as an alternative option for the management of venous congestion when no viable veins are available.

MCNP HPGe detector benchmark with previously validated Cyltran model.

Science.gov (United States)

Hau, I D; Russ, W R; Bronson, F

2009-05-01

An exact copy of the detector model generated for Cyltran was reproduced as an MCNP input file and the detection efficiency was calculated similarly with the methodology used in previous experimental measurements and simulation of a 280 cm(3) HPGe detector. Below 1000 keV the MCNP data correlated to the Cyltran results within 0.5% while above this energy the difference between MCNP and Cyltran increased to about 6% at 4800 keV, depending on the electron cut-off energy.

Program of assessment of mechanical and corrosion mechanical properties of reactor internals materials due to operation conditions in WWERs

International Nuclear Information System (INIS)

Ruscak, M.; Zamboch, M.

1998-01-01

Reactor internals are subject to three principle operation influences: neutron and gamma irradiation, mechanical stresses, both static and dynamic, and coolant chemistry. Several cases of damage have been reported in previous years in both boiling and pressure water reactors. They are linked with the term of irradiation assisted stress corrosion cracking as a possible damage mechanism. In WWERs, the principal material used for reactor internals is austenitic titanium stabilized stainless steel 08Kh18N10T, however high strength steels are used as well. To assess the changes of mechanical properties and to determine whether sensitivity to intergranular cracking can be increased by high neutron fluences, the experimental program has been started. The goal is to assure safe operation of the internals as well as life management for all planned operation period. The program consists of tests of material properties, both mechanical and corrosion-mechanical. Detailed neutron fluxes calculation as well as stress and deformation calculations are part of the assessment. Model of change will be proposed in order to plan inspections of the facility. In situ measurements of internals will be used to monitor exact status of structure during operation. Tensile specimens manufactured from both base metal and model weld joint have been irradiated to the total fluences of 3-20 dpa. Changes of mechanical properties are tested by the tensile test, stress corrosion cracking tests are performed in the autoclave with water loop and active loading. Operation temperature, pressure and water chemistry are chosen for the tests. (author)

Exercise-induced rhabdomyolysis mechanisms and prevention: A literature review

Directory of Open Access Journals (Sweden)

Jooyoung Kim

2016-09-01

Full Text Available Exercise-induced rhabdomyolysis (exRML, a pathophysiological condition of skeletal muscle cell damage that may cause acute renal failure and in some cases death. Increased Ca2+ level in cells along with functional degradation of cell signaling system and cell matrix have been suggested as the major pathological mechanisms associated with exRML. The onset of exRML may be exhibited in athletes as well as in general population. Previous studies have reported that possible causes of exRML were associated with excessive eccentric contractions in high temperature, abnormal electrolytes balance, and nutritional deficiencies possible genetic defects. However, the underlying mechanisms of exRML have not been clearly established among health professionals or sports medicine personnel. Therefore, we reviewed the possible mechanisms and correlated prevention of exRML, while providing useful and practical information for the athlete and general exercising population.

Advanced waterflooding in chalk reservoirs: Understanding of underlying mechanisms

DEFF Research Database (Denmark)

Zahid, Adeel; Sandersen, Sara Bülow; Stenby, Erling Halfdan

2011-01-01

Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recove...... of a microemulsion phase could be the possible reasons for the observed increase in oil recovery with sulfate ions at high temperature in chalk reservoirs besides the mechanism of the rock wettability alteration, which has been reported in most previous studies.......Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recovery...

Transient Dynamic Mechanical Analysis of Resilin-based Elastomeric Hydrogels

Science.gov (United States)

Li, Linqing; Kiick, Kristi

2014-04-01

The outstanding high-frequency properties of emerging resilin-like polypeptides (RLPs) have motivated their development for vocal fold tissue regeneration and other applications. Recombinant RLP hydrogels show efficient gelation, tunable mechanical properties, and display excellent extensibility, but little has been reported about their transient mechanical properties. In this manuscript, we describe the transient mechanical behavior of new RLP hydrogels investigated via both sinusoidal oscillatory shear deformation and uniaxial tensile testing. Oscillatory stress relaxation and creep experiments confirm that RLP-based hydrogels display significantly reduced stress relaxation and improved strain recovery compared to PEG-based control hydrogels. Uniaxial tensile testing confirms the negligible hysteresis, reversible elasticity and superior resilience (up to 98%) of hydrated RLP hydrogels, with Young’s modulus values that compare favorably with those previously reported for resilin and that mimic the tensile properties of the vocal fold ligament at low strain (engineering applications, of a range of RLP hydrogels.

L-ALLIANCE: a mechanism for adaptive action selection in heterogeneous multi-robot teams

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E.

1995-11-01

In practical applications of robotics, it is usually quite difficult, if not impossible, for the system designer to fully predict the environmental states in which the robots will operate. The complexity of the problem is further increased when dealing with teams of robots which themselves may be incompletely known and characterized in advance. It is thus highly desirable for robot teams to be able to adapt their performance during the mission due to changes in the environment, or to changes in other robot team members. In previous work, we introduced a behavior-based mechanism called the ALLIANCE architecture -- that facilitates the fault tolerant cooperative control of multi-robot teams. However, this previous work did not address the issue of how to dynamically update the control parameters during a mission to adapt to ongoing changes in the environment or in the robot team, and to ensure the efficiency of the collective team actions. In this paper, we address this issue by proposing the L-ALLIANCE mechanism, which defines an automated method whereby robots can use knowledge learned from previous experience to continually improve their collective action selection when working on missions composed of loosely coupled, discrete subtasks. This ability to dynamically update robotic control parameters provides a number of distinct advantages: it alleviates the need for human tuning of control parameters, it facilitates the use of custom-designed multi-robot teams for any given application, it improves the efficiency of the mission performance, and It allows robots to continually adapt their performance over time due to changes in the robot team and/or the environment. We describe the L-ALLIANCE mechanism, present the results of various alternative update strategies we investigated, present the formal model of the L-ALLIANCE mechanism, and present the results of a simple proof of concept implementation on a small team of heterogeneous mobile robots.

77 FR 44113 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

Science.gov (United States)

2012-07-27

... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (Type Certificate previously held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150... to the manufacturer. This action was prompted by a report from the Civil Aviation Authority of Israel...

77 FR 58323 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

Science.gov (United States)

2012-09-20

... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... Previously Held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150 airplanes. This proposed AD was.... Discussion The Civil Aviation Authority of Israel (CAAI), which is the aviation authority for Israel, has...

77 FR 32069 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

Science.gov (United States)

2012-05-31

... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200 airplanes. This proposed... receive about this proposed AD. Discussion The Civil Aviation Authority of Israel (CAAI), which is the...

Association between previous splenectomy and gastric dilatation-volvulus in dogs: 453 cases (2004-2009).

Science.gov (United States)

Sartor, Angela J; Bentley, Adrienne M; Brown, Dorothy C

2013-05-15

To evaluate the association between previous splenectomy and gastric dilatation-volvulus (GDV) in dogs. Multi-institutional retrospective case-control study. Animals-151 dogs treated surgically for GDV and 302 control dogs with no history of GDV. Computerized records of dogs evaluated via exploratory laparotomy or abdominal ultrasonography were searched, and dogs with GDV and dogs without GDV (control dogs) were identified. Two control dogs were matched with respect to age, body weight, sex, neuter status, and breed to each dog with GDV. Data were collected on the presence or absence of the spleen for both dogs with GDV and control dogs. Conditional logistic regression analysis was used to investigate the association of previous splenectomy with GDV. 6 (4%) dogs in the GDV group and 3 (1%) dogs in the control group had a history of previous splenectomy. The odds of GDV in dogs with a history of previous splenectomy in this population of dogs were 5.3 times those of dogs without a history of previous splenectomy (95% confidence interval, 1.1 to 26.8). For the patients in the present study, there was an increased odds of GDV in dogs with a history of splenectomy. Prophylactic gastropexy may be considered in dogs undergoing a splenectomy, particularly if other risk factors for GDV are present.

Scientific opinion on the evaluation of substances as acceptable previous cargoes for edible fats and oils

DEFF Research Database (Denmark)

Petersen, Annette

Shipping of edible fats and oils into Europe is permitted in bulk tanks, provided that the previous cargo is included in a positive list. The European Commission requested EFSA to evaluate the acceptability as previous cargoes for fats and oils the substances calcium lignosulphonate, methyl acetate...... the criteria for acceptability as previous cargoes. Due to uncertainties, mainly with regard to the composition and toxicity of the low molecular mass fraction, and the fact that the toxicological database is limited to the 40–65 grade and does not cover all grades of calcium lignosulphonate shipped...... as previous cargoes, the EFSA Panel on Contaminants in the Food Chain (CONTAM Panel) concluded that calcium lignosulphonate does not meet the criteria for acceptability as a previous cargo. Only food-grade ammonium sulphate meets the criteria for acceptability as a previous cargo due to uncertainties about...

Cation solvation with quantum chemical effects modeled by a size-consistent multi-partitioning quantum mechanics/molecular mechanics method.

Science.gov (United States)

Watanabe, Hiroshi C; Kubillus, Maximilian; Kubař, Tomáš; Stach, Robert; Mizaikoff, Boris; Ishikita, Hiroshi

2017-07-21

In the condensed phase, quantum chemical properties such as many-body effects and intermolecular charge fluctuations are critical determinants of the solvation structure and dynamics. Thus, a quantum mechanical (QM) molecular description is required for both solute and solvent to incorporate these properties. However, it is challenging to conduct molecular dynamics (MD) simulations for condensed systems of sufficient scale when adapting QM potentials. To overcome this problem, we recently developed the size-consistent multi-partitioning (SCMP) quantum mechanics/molecular mechanics (QM/MM) method and realized stable and accurate MD simulations, using the QM potential to a benchmark system. In the present study, as the first application of the SCMP method, we have investigated the structures and dynamics of Na + , K + , and Ca 2+ solutions based on nanosecond-scale sampling, a sampling 100-times longer than that of conventional QM-based samplings. Furthermore, we have evaluated two dynamic properties, the diffusion coefficient and difference spectra, with high statistical certainty. Furthermore the calculation of these properties has not previously been possible within the conventional QM/MM framework. Based on our analysis, we have quantitatively evaluated the quantum chemical solvation effects, which show distinct differences between the cations.

Mechanisms of Hg(II) uptake and methylation in methylating bacteria

Energy Technology Data Exchange (ETDEWEB)

Morel, Francois M. M. [Princeton Univ., NJ (United States). Geosciences

2016-10-14

The goal of this project was to understand the critical factors which control the availability and transport of Hg(II) into cells, a first step in the production of the neurotoxin, methylmercury. Specifically, this research focused on understanding the mechanism of bacterial mercury uptake and how mercury speciation affects the specificity and kinetics of mercury transport. Our research has shown that Hg(II) uptake in three different iron and sulfate-reducing proteobacteria occurs by the following mechanism (1) : Hg(II) uptake is an active transport process requiring energy, (2) it is dependent upon the structure of the Hg binding ligand, and (3) it is mediated by a heavy metal transporter such as one which transports the essential metal, Zn(II). In order to determine whether this mechanism extends to more diverse phylogenetic groups, we have begun examining Hg(II) uptake and bioavailability in two representative Hg methylating strains within the Firmicutes. These organisms have remarkably different membrane structures distinct from the Proteobacteria. Our results show low uptake rates in these two species of Firmicutes relative to the previously characterized Proteobacteria. This may explain the low methylation rates and yields observed in these organisms. Most surprisingly, however, these organisms appear to take up Hg(II) passively, as the addition of a protonophore failed to reduce Hg(II) uptake in these organisms. This is quite different to what has been observed previously for the Proteobacteria and suggests a different mechanism for Hg(II) uptake in the Firmicutes. We are continuing to understand and describe Hg(II) uptake in these organisms. A manuscript is expected to be submitted on this research in June 2016.

Hierarchical assembly strategy and multiscale structural origin of exceptional mechanical performance in nacre

Science.gov (United States)

Huang, Zaiwang

Nacre (mother of pearl) is a self-assembled hierarchical nanocomposite in possession of exquisite multiscale architecture and exceptional mechanical properties. Previous work has shown that the highly-ordered brick-mortar-like structure in nacre is assembled via epitaxial growth and the aragonite platelets are pure single-crystals. Our results challenge this conclusion and propose that nacre's individual aragonite platelets are constructed with highly-aligned aragonite nanoparticles mediated by screw dislocation and amorphous aggregation. The underlying physics mechanism why the aragonite nanoparticles choose highly-oriented attachment as its crystallization pathway is rationalized in terms of thermodynamics. The aragonite nanoparticle order-disorder transformation can be triggered by high temperature and mechanical deformation, which in turn confirms that the aragonite nanoparticles are basic building blocks for aragonite platelets. Particularly fascinating is the fracture toughness enhancement of nacre through exquisitely collecting mechanically inferior calcium carbonate (CaCO3) and biomolecules. The sandwich-like microarchitecture with a geometrically staggered arrangement can induce crack deflection along its biopolymer interface, thus significantly enhancing nacre's fracture toughness. Our new findings ambiguously demonstrate that, aside from crack deflection, the advancing crack can invade aragonite platelet, leaving a zigzag crack propagation pathway. These unexpected experimental observations disclose, for the first time, the inevitable structural role of aragonite platelets in enhancing nacre's fracture toughness. Simultaneously, the findings that the crack propagates in a zigzag manner within individual aragonite platelets overturn the previously well-established wisdom that considers aragonite platelets as brittle single-crystals. Moreover, we investigated the dynamical mechanical response of nacre under unixial compression. Our results show that the

Do emotional intelligence and previous caring experience influence student nurse performance? A comparative analysis.

Science.gov (United States)

Stenhouse, Rosie; Snowden, Austyn; Young, Jenny; Carver, Fiona; Carver, Hannah; Brown, Norrie

2016-08-01

Reports of poor nursing care have focused attention on values based selection of candidates onto nursing programmes. Values based selection lacks clarity and valid measures. Previous caring experience might lead to better care. Emotional intelligence (EI) might be associated with performance, is conceptualised and measurable. To examine the impact of 1) previous caring experience, 2) emotional intelligence 3) social connection scores on performance and retention in a cohort of first year nursing and midwifery students in Scotland. A longitudinal, quasi experimental design. Adult and mental health nursing, and midwifery programmes in a Scottish University. Adult, mental health and midwifery students (n=598) completed the Trait Emotional Intelligence Questionnaire-short form and Schutte's Emotional Intelligence Scale on entry to their programmes at a Scottish University, alongside demographic and previous caring experience data. Social connection was calculated from a subset of questions identified within the TEIQue-SF in a prior factor and Rasch analysis. Student performance was calculated as the mean mark across the year. Withdrawal data were gathered. 598 students completed baseline measures. 315 students declared previous caring experience, 277 not. An independent-samples t-test identified that those without previous caring experience scored higher on performance (57.33±11.38) than those with previous caring experience (54.87±11.19), a statistically significant difference of 2.47 (95% CI, 0.54 to 4.38), t(533)=2.52, p=.012. Emotional intelligence scores were not associated with performance. Social connection scores for those withdrawing (mean rank=249) and those remaining (mean rank=304.75) were statistically significantly different, U=15,300, z=-2.61, p$_amp_$lt;0.009. Previous caring experience led to worse performance in this cohort. Emotional intelligence was not a useful indicator of performance. Lower scores on the social connection factor were associated

Mechanism for the anti-thyroid action of minocycline

Energy Technology Data Exchange (ETDEWEB)

Doerge, D.R.; Divi, R.L.; Deck, J. [National Center for Toxicological Research, Jefferson, AR (United States); Taurog, A. [Univ. of Texas, Dallas, TX (United States)

1997-01-01

Administration of minocycline (MN), a tetracycline antibiotic, produces a black pigment in the thyroids of humans and several species of experimental animals and antithyroid effects in rodents. We have previously shown that these effects appear to be related to interactions of MN with thyroid peroxidase (TPO), the key enzyme in thyroid hormone synthesis. In the present study, the mechanisms for inhibition of TPO-catalyzed iodination and coupling reactions by MN were investigated. 37 refs., 7 figs., 3 tabs.

Exercise induced ST elevation and residual myocardial ischemia in previous myocardial infarction

International Nuclear Information System (INIS)

Shimonagata, Tsuyoshi; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Saito, Muneyasu; Sumiyoshi, Tetsuya

1987-01-01

The purpose of this study was to evaluate the clinical significance of stress induced ST elevation on infarcted area in 65 patients with previous myocardial infarction (single vessel disease) who had stress thallium scan. Stress induced ST changes on infarcted area were compared with quantitative assessment of myocardial ischemia (thallium ischemic score; TIS) and extent of myocardial infarction (defect score; DS) derived from circumferential profile analysis. In patients with previous myocardial infarction in less than 3 month from the onset (n = 36), left ventricular ejection fraction (LVEF) and extent of abnormal LV wall motion were not significantly different between patients with stress induced ST elevation ( ≥ 2 mm, n = 26) and those with stress induced ST elevation ( < 2 mm, n = 10), while, in patients with previous myocardial infarction in more than 3 month (n = 29), patients with stress induced ST elevation ( ≥ 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with ST elevation ( < 2 mm, n = 14). In addition, the former showed significantly higher DS and significantly lower TIS than the latter. In patients with previous myocardial infarction in less than 3 month, patients with ST elevation ( ≥ 2 mm, n = 15) with prominent upright T wave (n = 15) had transient thallium defect in infarcted area in 73 % and they had significantly higher LVEF and TIS than those with ST elevation ( < 2 mm, n = 11). These results indicated that ST elevation in infarcted area reflect different significance according to the recovery of injured myocardium and stress induced ST elevation with prominent upright T wave in infarcted area reflect residual myocardial ischemia in less than 3 month from the onset of myocardial infarction. (author)

Electro-mechanical response of a 3D nerve bundle model to mechanical loads leading to axonal injury.

Science.gov (United States)

Cinelli, I; Destrade, M; Duffy, M; McHugh, P

2018-03-01

Traumatic brain injuries and damage are major causes of death and disability. We propose a 3D fully coupled electro-mechanical model of a nerve bundle to investigate the electrophysiological impairments due to trauma at the cellular level. The coupling is based on a thermal analogy of the neural electrical activity by using the finite element software Abaqus CAE 6.13-3. The model includes a real-time coupling, modulated threshold for spiking activation, and independent alteration of the electrical properties for each 3-layer fibre within a nerve bundle as a function of strain. Results of the coupled electro-mechanical model are validated with previously published experimental results of damaged axons. Here, the cases of compression and tension are simulated to induce (mild, moderate, and severe) damage at the nerve membrane of a nerve bundle, made of 4 fibres. Changes in strain, stress distribution, and neural activity are investigated for myelinated and unmyelinated nerve fibres, by considering the cases of an intact and of a traumatised nerve membrane. A fully coupled electro-mechanical modelling approach is established to provide insights into crucial aspects of neural activity at the cellular level due to traumatic brain injury. One of the key findings is the 3D distribution of residual stresses and strains at the membrane of each fibre due to mechanically induced electrophysiological impairments, and its impact on signal transmission. Copyright © 2017 John Wiley & Sons, Ltd.

How to prevent type 2 diabetes in women with previous gestational diabetes?

DEFF Research Database (Denmark)

Pedersen, Anne Louise Winkler; Terkildsen Maindal, Helle; Juul, Lise

2017-01-01

OBJECTIVES: Women with previous gestational diabetes (GDM) have a seven times higher risk of developing type 2 diabetes (T2DM) than women without. We aimed to review the evidence of effective behavioural interventions seeking to prevent T2DM in this high-risk group. METHODS: A systematic review...... of RCTs in several databases in March 2016. RESULTS: No specific intervention or intervention components were found superior. The pooled effect on diabetes incidence (four trials) was estimated to: -5.02 per 100 (95% CI: -9.24; -0.80). CONCLUSIONS: This study indicates that intervention is superior...... to no intervention in prevention of T2DM among women with previous GDM....

Fish quality – linking previous infections to the quality of consumers’ fillet

DEFF Research Database (Denmark)

The quality of the fish meat is dependent upon a wide range of biological and non-biological factors. In the present study it has been established that previous infections by Vibrio anguillarum in rainbow trout (Oncorhynchus mykiss) influence the quality of the fish meat (fillet) at slaughter more...... than after the fish have recovered from the infection. The texture of the fillet analysed by sensory analysis showed changes, which could be explained by previous tissue damage caused by the infection. These changes indicated formation of scars in affected tissue during the processes of tissue repair......, which gave rise to a more fibrous, tougher and flaky texture of the fillets....

Technique for sparing previously irradiated critical normal structures in salvage proton craniospinal irradiation

International Nuclear Information System (INIS)

McDonald, Mark W; Wolanski, Mark R; Simmons, Joseph W; Buchsbaum, Jeffrey C

2013-01-01

Cranial reirradiation is clinically appropriate in some cases but cumulative radiation dose to critical normal structures remains a practical concern. The authors developed a simple technique in 3D conformal proton craniospinal irradiation (CSI) to block organs at risk (OAR) while minimizing underdosing of adjacent target brain tissue. Two clinical cases illustrate the use of proton therapy to provide salvage CSI when a previously irradiated OAR required sparing from additional radiation dose. The prior radiation plan was coregistered to the treatment planning CT to create a planning organ at risk volume (PRV) around the OAR. Right and left lateral cranial whole brain proton apertures were created with a small block over the PRV. Then right and left lateral “inverse apertures” were generated, creating an aperture opening in the shape of the area previously blocked and blocking the area previously open. The inverse aperture opening was made one millimeter smaller than the original block to minimize the risk of dose overlap. The inverse apertures were used to irradiate the target volume lateral to the PRV, selecting a proton beam range to abut the 50% isodose line against either lateral edge of the PRV. Together, the 4 cranial proton fields created a region of complete dose avoidance around the OAR. Comparative photon treatment plans were generated with opposed lateral X-ray fields with custom blocks and coplanar intensity modulated radiation therapy optimized to avoid the PRV. Cumulative dose volume histograms were evaluated. Treatment plans were developed and successfully implemented to provide sparing of previously irradiated critical normal structures while treating target brain lateral to these structures. The absence of dose overlapping during irradiation through the inverse apertures was confirmed by film. Compared to the lateral X-ray and IMRT treatment plans, the proton CSI technique improved coverage of target brain tissue while providing the least

Virtual learning environment for interactive engagement with advanced quantum mechanics

Directory of Open Access Journals (Sweden)

Mads Kock Pedersen

2016-04-01

Full Text Available A virtual learning environment can engage university students in the learning process in ways that the traditional lectures and lab formats cannot. We present our virtual learning environment StudentResearcher, which incorporates simulations, multiple-choice quizzes, video lectures, and gamification into a learning path for quantum mechanics at the advanced university level. StudentResearcher is built upon the experiences gathered from workshops with the citizen science game Quantum Moves at the high-school and university level, where the games were used extensively to illustrate the basic concepts of quantum mechanics. The first test of this new virtual learning environment was a 2014 course in advanced quantum mechanics at Aarhus University with 47 enrolled students. We found increased learning for the students who were more active on the platform independent of their previous performances.

On the mechanism of hydrogen-promoted gold-catalyzed CO oxidation

KAUST Repository

Quinet, Elodie

2009-12-10

The kinetics of CO oxidation, H2 oxidation and preferential CO oxidation (PrOx) over Au/Al2O3 catalysts have been investigated. The catalysts with the smallest particles (∼2 nm) are the most active for all three reactions. As previously observed, the presence of H2 greatly promotes CO oxidation, which becomes faster than CO-free H2 oxidation at low temperature. From these results and on the basis of previous works, we propose a complete PrOx mechanism. The reaction involves Au-OOH, Au-OH and Au-H intermediates, also involved in H2 oxidation, and benefits from the presence of low-coordination sites. © 2009 Elsevier Inc. All rights reserved.

On the mechanism of hydrogen-promoted gold-catalyzed CO oxidation

KAUST Repository

Quinet, Elodie; Piccolo, Laurent; Morfin, Franck; Avenier, Priscilla; Diehl, Fabrice; Caps, Valerie; Rousset, Jean Luc

2009-01-01

The kinetics of CO oxidation, H2 oxidation and preferential CO oxidation (PrOx) over Au/Al2O3 catalysts have been investigated. The catalysts with the smallest particles (∼2 nm) are the most active for all three reactions. As previously observed, the presence of H2 greatly promotes CO oxidation, which becomes faster than CO-free H2 oxidation at low temperature. From these results and on the basis of previous works, we propose a complete PrOx mechanism. The reaction involves Au-OOH, Au-OH and Au-H intermediates, also involved in H2 oxidation, and benefits from the presence of low-coordination sites. © 2009 Elsevier Inc. All rights reserved.

Aortic pseudoaneurysm detected on external jugular venous distention following a Bentall procedure 10 years previously.

Science.gov (United States)

Fukunaga, Naoto; Shomura, Yu; Nasu, Michihiro; Okada, Yukikatsu

2010-11-01

An asymptomatic 49-year-old woman was admitted for the purpose of surgery for aortic pseudoaneurysm. She had Marfan syndrome and had undergone an emergent Bentall procedure 10 years previously. About six months previously, she could palpate distended bilateral external jugular veins, which became distended only in a supine position and without any other symptoms. Enhanced computed tomography revealed an aortic pseudoaneurysm originating from a previous distal anastomosis site. During induction of general anesthesia in a supine position, bilateral external jugular venous distention was remarkable. Immediately after a successful operation, distention completely resolved. The present case emphasizes the importance of physical examination leading to a diagnosis of asymptomatic life-threatening diseases in patients with a history of previous aortic surgery.

Relationship of deer and moose populations to previous winters' snow

Science.gov (United States)

Mech, L.D.; McRoberts, R.E.; Peterson, R.O.; Page, R.E.

1987-01-01

(1) Linear regression was used to relate snow accumulation during single and consecutive winters with white-tailed deer (Odocoileus virginianus) fawn:doe ratios, mosse (Alces alces) twinning rates and calf:cow ratios, and annual changes in deer and moose populations. Significant relationships were found between snow accumulation during individual winters and these dependent variables during the following year. However, the strongest relationships were between the dependent variables and the sums of the snow accumulations over the previous three winters. The percentage of the variability explained was 36 to 51. (2) Significant relationships were also found between winter vulnerability of moose calves and the sum of the snow accumulations in the current, and up to seven previous, winters, with about 49% of the variability explained. (3) No relationship was found between wolf numbers and the above dependent variables. (4) These relationships imply that winter influences on maternal nutrition can accumulate for several years and that this cumulative effect strongly determines fecundity and/or calf and fawn survivability. Although wolf (Canis lupus L.) predation is the main direct mortality agent on fawns and calves, wolf density itself appears to be secondary to winter weather in influencing the deer and moose populations.

Virus spreading in wireless sensor networks with a medium access control mechanism

International Nuclear Information System (INIS)

Wang Ya-Qi; Yang Xiao-Yuan

2013-01-01

In this paper, an extended version of standard susceptible-infected (SI) model is proposed to consider the influence of a medium access control mechanism on virus spreading in wireless sensor networks. Theoretical analysis shows that the medium access control mechanism obviously reduces the density of infected nodes in the networks, which has been ignored in previous studies. It is also found that by increasing the network node density or node communication radius greatly increases the number of infected nodes. The theoretical results are confirmed by numerical simulations. (general)

Classical mechanics and electromagnetism in accelerator physics

CERN Document Server

Stupakov, Gennady

2018-01-01

This self-contained textbook with exercises discusses a broad range of selected topics from classical mechanics and electromagnetic theory that inform key issues related to modern accelerators. Part I presents fundamentals of the Lagrangian and Hamiltonian formalism for mechanical systems, canonical transformations, action-angle variables, and then linear and nonlinear oscillators. The Hamiltonian for a circular accelerator is used to evaluate the equations of motion, the action, and betatron oscillations in an accelerator. From this base, we explore the impact of field errors and nonlinear resonances. This part ends with the concept of the distribution function and an introduction to the kinetic equation to describe large ensembles of charged particles and to supplement the previous single-particle analysis of beam dynamics. Part II focuses on classical electromagnetism and begins with an analysis of the electromagnetic field from relativistic beams, both in vacuum and in a resistive pipe. Plane electromagne...

A method for generating reduced-order combustion mechanisms that satisfy the differential entropy inequality

Science.gov (United States)

Ream, Allen E.; Slattery, John C.; Cizmas, Paul G. A.

2018-04-01

This paper presents a new method for determining the Arrhenius parameters of a reduced chemical mechanism such that it satisfies the second law of thermodynamics. The strategy is to approximate the progress of each reaction in the reduced mechanism from the species production rates of a detailed mechanism by using a linear least squares method. A series of non-linear least squares curve fittings are then carried out to find the optimal Arrhenius parameters for each reaction. At this step, the molar rates of production are written such that they comply with a theorem that provides the sufficient conditions for satisfying the second law of thermodynamics. This methodology was used to modify the Arrhenius parameters for the Westbrook and Dryer two-step mechanism and the Peters and Williams three-step mechanism for methane combustion. Both optimized mechanisms showed good agreement with the detailed mechanism for species mole fractions and production rates of most major species. Both optimized mechanisms showed significant improvement over previous mechanisms in minor species production rate prediction. Both optimized mechanisms produced no violations of the second law of thermodynamics.

[Electronic cigarettes - effects on health. Previous reports].

Science.gov (United States)

Napierała, Marta; Kulza, Maksymilian; Wachowiak, Anna; Jabłecka, Katarzyna; Florek, Ewa

2014-01-01

Currently very popular in the market of tobacco products have gained electronic cigarettes (ang. E-cigarettes). These products are considered to be potentially less harmful in compared to traditional tobacco products. However, current reports indicate that the statements of the producers regarding to the composition of the e- liquids not always are sufficient, and consumers often do not have reliable information on the quality of the product used by them. This paper contain a review of previous reports on the composition of e-cigarettes and their impact on health. Most of the observed health effects was related to symptoms of the respiratory tract, mouth, throat, neurological complications and sensory organs. Particularly hazardous effects of the e-cigarettes were: pneumonia, congestive heart failure, confusion, convulsions, hypotension, aspiration pneumonia, face second-degree burns, blindness, chest pain and rapid heartbeat. In the literature there is no information relating to passive exposure by the aerosols released during e-cigarette smoking. Furthermore, the information regarding to the use of these products in the long term are not also available.

Wives without husbands: gendered vulnerability to sexually transmitted infections among previously married women in India.

Science.gov (United States)

Walters, Kimberly; Dandona, Rakhi; Walters, Lawrence C; Lakshmi, Vemu; Dandona, Lalit; Schneider, John A

2012-01-01

Using population-based and family structural data from a high HIV-prevalence district of Southern India, this paper considers four suggested social scenarios used to explain the positive correlation between HIV prevalence and previously married status among Indian women: (1) infection from and then bereavement of an infected husband; (2) abandonment after husbands learn of their wives' HIV status; (3) economic instability after becoming previously married, leading women to seek financial support through male partners; and (4) the social status of being previously married exposing women to sexual harassment and predation. By also considering seroprevalence of two other common sexually transmitted infections (STIs), herpes and syphilis, in a combined variable with HIV, we limit the likelihood of the first two scenarios accounting for the greater part of this correlation. Through a nuanced analysis of household residences patterns (family structure), standard of living, and education, we also limit the probability that scenario three explains a greater portion of the correlation. Scenario four emerges as the most likely explanation for this correlation, recognizing that other scenarios are also possible. Further, the interdisciplinary literature on the social position of previously married women in India strongly supports the suggestion that, as a population, previously married women are sexually vulnerable in India. Previously married status as an STI risk factor requires further biosocial research and warrants concentrated public health attention.

A discrete model to study reaction-diffusion-mechanics systems.

Science.gov (United States)

Weise, Louis D; Nash, Martyn P; Panfilov, Alexander V

2011-01-01

This article introduces a discrete reaction-diffusion-mechanics (dRDM) model to study the effects of deformation on reaction-diffusion (RD) processes. The dRDM framework employs a FitzHugh-Nagumo type RD model coupled to a mass-lattice model, that undergoes finite deformations. The dRDM model describes a material whose elastic properties are described by a generalized Hooke's law for finite deformations (Seth material). Numerically, the dRDM approach combines a finite difference approach for the RD equations with a Verlet integration scheme for the equations of the mass-lattice system. Using this framework results were reproduced on self-organized pacemaking activity that have been previously found with a continuous RD mechanics model. Mechanisms that determine the period of pacemakers and its dependency on the medium size are identified. Finally it is shown how the drift direction of pacemakers in RDM systems is related to the spatial distribution of deformation and curvature effects.

Mechanisms of Evolution in High-Consequence Drug Resistance Plasmids

Directory of Open Access Journals (Sweden)

Susu He

2016-12-01

Full Text Available The dissemination of resistance among bacteria has been facilitated by the fact that resistance genes are usually located on a diverse and evolving set of transmissible plasmids. However, the mechanisms generating diversity and enabling adaptation within highly successful resistance plasmids have remained obscure, despite their profound clinical significance. To understand these mechanisms, we have performed a detailed analysis of the mobilome (the entire mobile genetic element content of a set of previously sequenced carbapenemase-producing Enterobacteriaceae (CPE from the National Institutes of Health Clinical Center. This analysis revealed that plasmid reorganizations occurring in the natural context of colonization of human hosts were overwhelmingly driven by genetic rearrangements carried out by replicative transposons working in concert with the process of homologous recombination. A more complete understanding of the molecular mechanisms and evolutionary forces driving rearrangements in resistance plasmids may lead to fundamentally new strategies to address the problem of antibiotic resistance.

Molecular mechanism of extreme mechanostability in a pathogen adhesin.

Science.gov (United States)

Milles, Lukas F; Schulten, Klaus; Gaub, Hermann E; Bernardi, Rafael C

2018-03-30

High resilience to mechanical stress is key when pathogens adhere to their target and initiate infection. Using atomic force microscopy-based single-molecule force spectroscopy, we explored the mechanical stability of the prototypical staphylococcal adhesin SdrG, which targets a short peptide from human fibrinogen β. Steered molecular dynamics simulations revealed, and single-molecule force spectroscopy experiments confirmed, the mechanism by which this complex withstands forces of over 2 nanonewtons, a regime previously associated with the strength of a covalent bond. The target peptide, confined in a screwlike manner in the binding pocket of SdrG, distributes forces mainly toward the peptide backbone through an intricate hydrogen bond network. Thus, these adhesins can attach to their target with exceptionally resilient mechanostability, virtually independent of peptide side chains. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

TALE proteins search DNA using a rotationally decoupled mechanism.

Science.gov (United States)

Cuculis, Luke; Abil, Zhanar; Zhao, Huimin; Schroeder, Charles M

2016-10-01

Transcription activator-like effector (TALE) proteins are a class of programmable DNA-binding proteins used extensively for gene editing. Despite recent progress, however, little is known about their sequence search mechanism. Here, we use single-molecule experiments to study TALE search along DNA. Our results show that TALEs utilize a rotationally decoupled mechanism for nonspecific search, despite remaining associated with DNA templates during the search process. Our results suggest that the protein helical structure enables TALEs to adopt a loosely wrapped conformation around DNA templates during nonspecific search, facilitating rapid one-dimensional (1D) diffusion under a range of solution conditions. Furthermore, this model is consistent with a previously reported two-state mechanism for TALE search that allows these proteins to overcome the search speed-stability paradox. Taken together, our results suggest that TALE search is unique among the broad class of sequence-specific DNA-binding proteins and supports efficient 1D search along DNA.

A discrete model to study reaction-diffusion-mechanics systems.

Directory of Open Access Journals (Sweden)

Louis D Weise

Full Text Available This article introduces a discrete reaction-diffusion-mechanics (dRDM model to study the effects of deformation on reaction-diffusion (RD processes. The dRDM framework employs a FitzHugh-Nagumo type RD model coupled to a mass-lattice model, that undergoes finite deformations. The dRDM model describes a material whose elastic properties are described by a generalized Hooke's law for finite deformations (Seth material. Numerically, the dRDM approach combines a finite difference approach for the RD equations with a Verlet integration scheme for the equations of the mass-lattice system. Using this framework results were reproduced on self-organized pacemaking activity that have been previously found with a continuous RD mechanics model. Mechanisms that determine the period of pacemakers and its dependency on the medium size are identified. Finally it is shown how the drift direction of pacemakers in RDM systems is related to the spatial distribution of deformation and curvature effects.

The equivalence myth of quantum mechanics-part II

Science.gov (United States)

Muller, F. A.

The author endeavours to show two things: first, that Schrödingers (and Eckarts) demonstration in March (September) 1926 of the equivalence of matrix mechanics, as created by Heisenberg, Born, Jordan and Dirac in 1925, and wave mechanics, as created by Schrödinger in 1926, is not foolproof; and second, that it could not have been foolproof, because at the time matrix mechanics and wave mechanics were neither mathematically nor empirically equivalent. That they were is the Equivalence Myth. In order to make the theories equivalent and to prove this, one has to leave the historical scene of 1926 and wait until 1932, when von Neumann finished his magisterial edifice. During the period 1926-1932 the original families of mathematical structures of matrix mechanics and of wave mechanics were stretched, parts were chopped off and novel structures were added. To Procrustean places we go, where we can demonstrate the mathematical, empirical and ontological equivalence of 'the final versions of' matrix mechanics and wave mechanics. The present paper claims to be a comprehensive analysis of one of the pivotal papers in the history of quantum mechanics: Schrödingers equivalence paper. Since the analysis is performed from the perspective of Suppes structural view ('semantic view') of physical theories, the present paper can be regarded not only as a morsel of the internal history of quantum mechanics, but also as a morsel of applied philosophy of science. The paper is self-contained and presupposes only basic knowledge of quantum mechanics. For reasons of length, the paper is published in two parts; Part I appeared in the previous issue of this journal. Section 1 contains, besides an introduction, also the papers five claims and a preview of the arguments supporting these claims; so Part I, Section 1 may serve as a summary of the paper for those readers who are not interested in the detailed arguments.

AbobotulinumtoxinA Efficacy and Safety in Children With Equinus Foot Previously Treated With Botulinum Toxin.

Science.gov (United States)

Dabrowski, Edward; Bonikowski, Marcin; Gormley, Mark; Volteau, Magali; Picaut, Philippe; Delgado, Mauricio R

2018-05-01

The effects of botulinum toxin are transient, and repeat injections are required in children with lower-limb spasticity. However, the efficacy of botulinum toxin in patients who have received previous injections has remained largely unexplored. We present subgroup analyses of a phase III study conducted in ambulatory children (aged two to 17) with spastic equinus foot. Patients were randomized to single doses of abobotulinumtoxinA 10 U/kg/leg, 15 U/kg/leg, or placebo injected into the gastrocnemius-soleus complex (one or both legs). The first analysis was prespecified to review the effect of abobotulinumtoxinA in children previously treated with botulinum toxin versus those children new to the treatment; a second post hoc analysis evaluated the effect of abobotulinumtoxinA in children who changed botulinum toxin formulation. Of the 241 randomized patients, 113 had previously received botulinum toxin, including 86 who had been treated with another formulation. In both analyses, muscle tone (Modified Ashworth Scale) and the Physicians Global Assessment, at week 4, improved with abobotulinumtoxinA treatment versus placebo, regardless of baseline botulinum toxin status. Placebo responses in patients new to treatment were consistently higher than in the previously treated group. These results demonstrate similar abobotulinumtoxinA efficacy and safety profiles in children with spasticity who are new to botulinum toxin treatment and those children who were previously treated. The efficacy and safety of abobotulinumtoxinA treatment in these previously treated patients were comparable with the overall trial population, indicating that doses of 10 and 15 U/kg/leg are suitable starting doses for children with spasticity regardless of the previous botulinum toxin preparation used. Copyright © 2018 Elsevier Inc. All rights reserved.

Survival of dental implants placed in sites of previously failed implants.

Science.gov (United States)

Chrcanovic, Bruno R; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

2017-11-01

To assess the survival of dental implants placed in sites of previously failed implants and to explore the possible factors that might affect the outcome of this reimplantation procedure. Patients that had failed dental implants, which were replaced with the same implant type at the same site, were included. Descriptive statistics were used to describe the patients and implants; survival analysis was also performed. The effect of systemic, environmental, and local factors on the survival of the reoperated implants was evaluated. 175 of 10,096 implants in 98 patients were replaced by another implant at the same location (159, 14, and 2 implants at second, third, and fourth surgeries, respectively). Newly replaced implants were generally of similar diameter but of shorter length compared to the previously placed fixtures. A statistically significant greater percentage of lost implants were placed in sites with low bone quantity. There was a statistically significant difference (P = 0.032) in the survival rates between implants that were inserted for the first time (94%) and implants that replaced the ones lost (73%). There was a statistically higher failure rate of the reoperated implants for patients taking antidepressants and antithrombotic agents. Dental implants replacing failed implants had lower survival rates than the rates reported for the previous attempts of implant placement. It is suggested that a site-specific negative effect may possibly be associated with this phenomenon, as well as the intake of antidepressants and antithrombotic agents. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A Flux-Pinning Mechanism for Segment Assembly and Alignment

Science.gov (United States)

Gersh-Range, Jessica A.; Arnold, William R.; Peck, Mason A.; Stahl, H. Philip

2011-01-01

Currently, the most compelling astrophysics questions include how planets and the first stars formed and whether there are protostellar disks that contain large organic molecules. Although answering these questions requires space telescopes with apertures of at least 10 meters, such large primaries are challenging to construct by scaling up previous designs; the limited capacity of a launch vehicle bounds the maximum diameter of a monolithic primary, and beyond a certain size, deployable telescopes cannot fit in current launch vehicle fairings. One potential solution is connecting the primary mirror segments edgewise using flux-pinning mechanisms, which are analogous to non-contacting damped springs. In the baseline design, a flux-pinning mechanism consists of a magnet and a superconductor separated by a predetermined gap, with the damping adjusted by placing aluminum near the interface. Since flux pinning is possible only when the superconductor is cooled below a critical temperature, flux-pinning mechanisms are uniquely suited for cryogenic space telescopes. By placing these mechanisms along the edges of the mirror segments, a primary can be built up over time. Since flux pinning requires no mechanical deployments, the assembly process could be robotic or use some other non-contacting scheme. Advantages of this approach include scalability and passive stability.

Hypertensive response to exercise: mechanisms and clinical implication.

Science.gov (United States)

Kim, Darae; Ha, Jong-Won

2016-01-01

A hypertensive response to exercise (HRE) is frequently observed in individuals without hypertension or other cardiovascular disease. However, mechanisms and clinical implication of HRE is not fully elucidated. Endothelial dysfunction and increased stiffness of large artery contribute to development of HRE. From neurohormonal aspects, excess stimulation of sympathetic nervous system and augmented rise of angiotensin II seems to be important mechanism in HRE. Increasing evidences indicates that a HRE is associated with functional and structural abnormalities of left ventricle, especially when accompanied by increased central blood pressure. A HRE harbors prognostic significance in future development of hypertension and increased cardiovascular events, particularly if a HRE is documented in moderate intensity of exercise. As supported by previous studies, a HRE is not a benign phenomenon, however, currently, whether to treat a HRE is controversial with uncertain treatment strategy. Considering underlying mechanisms, angiotensin receptor blockers and beta blockers can be suggested in individuals with HRE, however, evidences for efficacy and outcomes of treatment of HRE in individuals without hypertension is scarce and therefore warrants further studies.

Increased risk of default among previously treated tuberculosis cases in the Western Cape Province, South Africa.

Science.gov (United States)

Marx, F M; Dunbar, R; Hesseling, A C; Enarson, D A; Fielding, K; Beyers, N

2012-08-01

To investigate, in two urban communities with high tuberculosis (TB) incidence and high rates of TB recurrence, whether a history of previous TB treatment is associated with treatment default. Retrospective cohort study of TB cases with an episode of treatment recorded in the clinic-based treatment registers between 2002 and 2007. Probabilistic record linkage was used to ascertain treatment history of TB cases back to 1996. Based on the outcome of their most recent previous treatment episode, previously treated cases were compared to new cases regarding their risk of treatment default. Previous treatment success (adjusted odds ratio [aOR] 1.79; 95%CI 1.17-2.73), previous default (aOR 6.18, 95%CI 3.68-10.36) and previous failure (aOR 9.72, 95%CI 3.07-30.78) were each independently associated with treatment default (P default were male sex (P = 0.003) and age 19-39 years (P risk of treatment default, even after previous successful treatment. This finding is of particular importance in a setting where recurrent TB is very common. Adherence to treatment should be ensured in new and retreatment cases to increase cure rates and reduce transmission of TB in the community.

Parametrization of Combined Quantum Mechanical and Molecular Mechanical Methods: Bond-Tuned Link Atoms

Directory of Open Access Journals (Sweden)

Xin-Ping Wu

2018-05-01

Full Text Available Combined quantum mechanical and molecular mechanical (QM/MM methods are the most powerful available methods for high-level treatments of subsystems of very large systems. The treatment of the QM−MM boundary strongly affects the accuracy of QM/MM calculations. For QM/MM calculations having covalent bonds cut by the QM−MM boundary, it has been proposed previously to use a scheme with system-specific tuned fluorine link atoms. Here, we propose a broadly parametrized scheme where the parameters of the tuned F link atoms depend only on the type of bond being cut. In the proposed new scheme, the F link atom is tuned for systems with a certain type of cut bond at the QM−MM boundary instead of for a specific target system, and the resulting link atoms are call bond-tuned link atoms. In principle, the bond-tuned link atoms can be as convenient as the popular H link atoms, and they are especially well adapted for high-throughput and accurate QM/MM calculations. Here, we present the parameters for several kinds of cut bonds along with a set of validation calculations that confirm that the proposed bond-tuned link-atom scheme can be as accurate as the system-specific tuned F link-atom scheme.

Parametrization of Combined Quantum Mechanical and Molecular Mechanical Methods: Bond-Tuned Link Atoms.

Science.gov (United States)

Wu, Xin-Ping; Gagliardi, Laura; Truhlar, Donald G

2018-05-30

Combined quantum mechanical and molecular mechanical (QM/MM) methods are the most powerful available methods for high-level treatments of subsystems of very large systems. The treatment of the QM-MM boundary strongly affects the accuracy of QM/MM calculations. For QM/MM calculations having covalent bonds cut by the QM-MM boundary, it has been proposed previously to use a scheme with system-specific tuned fluorine link atoms. Here, we propose a broadly parametrized scheme where the parameters of the tuned F link atoms depend only on the type of bond being cut. In the proposed new scheme, the F link atom is tuned for systems with a certain type of cut bond at the QM-MM boundary instead of for a specific target system, and the resulting link atoms are call bond-tuned link atoms. In principle, the bond-tuned link atoms can be as convenient as the popular H link atoms, and they are especially well adapted for high-throughput and accurate QM/MM calculations. Here, we present the parameters for several kinds of cut bonds along with a set of validation calculations that confirm that the proposed bond-tuned link-atom scheme can be as accurate as the system-specific tuned F link-atom scheme.

Modular femoral component for conversion of previous hip surgery in total hip arthroplasty.

Science.gov (United States)

Goldstein, Wayne M; Branson, Jill J

2005-09-01

The conversion of previous hip surgery to total hip arthroplasty creates a durable construct that is anatomically accurate. Most femoral components with either cemented or cementless design have a fixed tapered proximal shape. The proximal femoral anatomy is changed due to previous hip surgery for fixation of an intertrochanteric hip fracture, proximal femoral osteotomy, or a fibular allograft for avascular necrosis. The modular S-ROM (DePuy Orthopaedics Inc., Warsaw, Ind) hip stem accommodates these issues and independently prepares the proximal and distal portion of the femur. In preparation and implantation, the S-ROM hip stem creates less hoop stresses on potentially fragile stress risers from screws and thin bone. The S-ROM hip stem also prepares a previously distorted anatomy by milling through cortical bone that can occlude the femoral medullar canals and recreate proper femoral anteversion and reduces the risk of intraoperative or postoperative periprosthetic fracture due to the flexible titanium-slotted stem. The S-ROM femoral stem is recommended for challenging total hip reconstructions.

2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference

Energy Technology Data Exchange (ETDEWEB)

Dr. Thomas Balk

2010-07-30

Over the past decades, it has been well established that the mechanical behavior of materials changes when they are confined geometrically at least in one dimension to small scale. It is the aim of the 2010 Gordon Conference on 'Thin Film and Small Scale Mechanical Behavior' to discuss cutting-edge research on elastic, plastic and time-dependent deformation as well as degradation mechanisms like fracture, fatigue and wear at small scales. As in the past, the conference will benefit from contributions from fundamental studies of physical mechanisms linked to material science and engineering reaching towards application in modern applications ranging from optical and microelectronic devices and nano- or micro-electrical mechanical systems to devices for energy production and storage. The conference will feature entirely new testing methodologies and in situ measurements as well as recent progress in atomistic and micromechanical modeling. Particularly, emerging topics in the area of energy conversion and storage, such as material for batteries will be highlighted. The study of small-scale mechanical phenomena in systems related to energy production, conversion or storage offer an enticing opportunity to materials scientists, who can provide new insight and investigate these phenomena with methods that have not previously been exploited.

Mechanical design of a high field common coil magnet

CERN Document Server

Caspi, S; Dietderich, D R; Gourlay, S A; Gupta, R; McInturff, A; Millos, G; Scanlan, R M

1999-01-01

A common coil design for high field 2-in-1 accelerator magnets has been previously presented as a "conductor-friendly" option for high field magnets applicable for a Very Large Hadron Collider. This paper presents the mechanical design for a 14 tesla 2-in-1 dipole based on the common coil design approach. The magnet will use a high current density Nb/sub 3/Sn conductor. The design addresses mechanical issues particular to the common coil geometry: horizontal support against coil edges, vertical preload on coil faces, end loading and support, and coil stresses and strains. The magnet is the second in a series of racetrack coil magnets that will provide experimental verification of the common coil design approach. (9 refs).

Mechanism of iron catalyzed oxidation of SO/sub 2/ in oxygenated solutions

Energy Technology Data Exchange (ETDEWEB)

Freiberg, J

1975-01-01

Previous experimental work concerning the iron catalyzed oxidation of SO/sub 2/ in oxygenated acid solutions failed to provide a consistent reaction mechanism and rate expression. As iron is one of the main constituents of urban atmospheric aerosols, the rate studies of heterogeneous sulphate formation in polluted city air were hampered. The present study develops a new theory for the iron catalyzed oxidation of SO/sub 2/. The resulting new rate expression is general enough to account for the results of previous experimental investigations that were performed in different ranges of SO/sub 2/ and catalyst concentrations.

Clec9a-Mediated Ablation of Conventional Dendritic Cells Suggests a Lymphoid Path to Generating Dendritic Cells In Vivo

Directory of Open Access Journals (Sweden)

Johanna Salvermoser

2018-04-01

Full Text Available Conventional dendritic cells (cDCs are versatile activators of immune responses that develop as part of the myeloid lineage downstream of hematopoietic stem cells. We have recently shown that in mice precursors of cDCs, but not of other leukocytes, are marked by expression of DNGR-1/CLEC9A. To genetically deplete DNGR-1-expressing cDC precursors and their progeny, we crossed Clec9a-Cre mice to Rosa-lox-STOP-lox-diphtheria toxin (DTA mice. These mice develop signs of age-dependent myeloproliferative disease, as has been observed in other DC-deficient mouse models. However, despite efficient depletion of cDC progenitors in these mice, cells with phenotypic characteristics of cDCs populate the spleen. These cells are functionally and transcriptionally similar to cDCs in wild type control mice but show somatic rearrangements of Ig-heavy chain genes, characteristic of lymphoid origin cells. Our studies reveal a previously unappreciated developmental heterogeneity of cDCs and suggest that the lymphoid lineage can generate cells with features of cDCs when myeloid cDC progenitors are impaired.

Comparison of S. cerevisiae F-BAR domain structures reveals a conserved inositol phosphate binding site

Science.gov (United States)

Moravcevic, Katarina; Alvarado, Diego; Schmitz, Karl R.; Kenniston, Jon A.; Mendrola, Jeannine M.; Ferguson, Kathryn M.; Lemmon, Mark A.

2015-01-01

SUMMARY F-BAR domains control membrane interactions in endocytosis, cytokinesis, and cell signaling. Although generally thought to bind curved membranes containing negatively charged phospholipids, numerous functional studies argue that differences in lipid-binding selectivities of F-BAR domains are functionally important. Here, we compare membrane-binding properties of the S. cerevisiae F-BAR domains in vitro and in vivo. Whereas some F-BAR domains (such as Bzz1p and Hof1p F-BARs) bind equally well to all phospholipids, the F-BAR domain from the RhoGAP Rgd1p preferentially binds phosphoinositides. We determined X-ray crystal structures of F-BAR domains from Hof1p and Rgd1p, the latter bound to an inositol phosphate. The structures explain phospholipid-binding selectivity differences, and reveal an F-BAR phosphoinositide binding site that is fully conserved in a mammalian RhoGAP called Gmip, and is partly retained in certain other F-BAR domains. Our findings reveal previously unappreciated determinants of F-BAR domain lipid-binding specificity, and provide a basis for its prediction from sequence. PMID:25620000

Orphan Nuclear Receptor ERRα Controls Macrophage Metabolic Signaling and A20 Expression to Negatively Regulate TLR-Induced Inflammation.

Science.gov (United States)

Yuk, Jae-Min; Kim, Tae Sung; Kim, Soo Yeon; Lee, Hye-Mi; Han, Jeongsu; Dufour, Catherine Rosa; Kim, Jin Kyung; Jin, Hyo Sun; Yang, Chul-Su; Park, Ki-Sun; Lee, Chul-Ho; Kim, Jin-Man; Kweon, Gi Ryang; Choi, Hueng-Sik; Vanacker, Jean-Marc; Moore, David D; Giguère, Vincent; Jo, Eun-Kyeong

2015-07-21

The orphan nuclear receptor estrogen-related receptor α (ERRα; NR3B1) is a key metabolic regulator, but its function in regulating inflammation remains largely unknown. Here, we demonstrate that ERRα negatively regulates Toll-like receptor (TLR)-induced inflammation by promoting Tnfaip3 transcription and fine-tuning of metabolic reprogramming in macrophages. ERRα-deficient (Esrra(-/-)) mice showed increased susceptibility to endotoxin-induced septic shock, leading to more severe pro-inflammatory responses than control mice. ERRα regulated macrophage inflammatory responses by directly binding the promoter region of Tnfaip3, a deubiquitinating enzyme in TLR signaling. In addition, Esrra(-/-) macrophages showed an increased glycolysis, but impaired mitochondrial respiratory function and biogenesis. Further, ERRα was required for the regulation of NF-κB signaling by controlling p65 acetylation via maintenance of NAD(+) levels and sirtuin 1 activation. These findings unravel a previously unappreciated role for ERRα as a negative regulator of TLR-induced inflammatory responses through inducing Tnfaip3 transcription and controlling the metabolic reprogramming. Copyright © 2015 Elsevier Inc. All rights reserved.

NFκB1 is a suppressor of neutrophil-driven hepatocellular carcinoma

Science.gov (United States)

Wilson, C. L.; Jurk, D.; Fullard, N.; Banks, P.; Page, A.; Luli, S.; Elsharkawy, A. M.; Gieling, R. G.; Chakraborty, J. Bagchi; Fox, C.; Richardson, C.; Callaghan, K.; Blair, G. E.; Fox, N.; Lagnado, A.; Passos, J. F.; Moore, A. J.; Smith, G. R.; Tiniakos, D. G.; Mann, J.; Oakley, F.; Mann, D. A.

2015-04-01

Hepatocellular carcinoma (HCC) develops on the background of chronic hepatitis. Leukocytes found within the HCC microenvironment are implicated as regulators of tumour growth. We show that diethylnitrosamine (DEN)-induced murine HCC is attenuated by antibody-mediated depletion of hepatic neutrophils, the latter stimulating hepatocellular ROS and telomere DNA damage. We additionally report a previously unappreciated tumour suppressor function for hepatocellular nfkb1 operating via p50:p50 dimers and the co-repressor HDAC1. These anti-inflammatory proteins combine to transcriptionally repress hepatic expression of a S100A8/9, CXCL1 and CXCL2 neutrophil chemokine network. Loss of nfkb1 promotes ageing-associated chronic liver disease (CLD), characterized by steatosis, neutrophillia, fibrosis, hepatocyte telomere damage and HCC. Nfkb1S340A/S340Amice carrying a mutation designed to selectively disrupt p50:p50:HDAC1 complexes are more susceptible to HCC; by contrast, mice lacking S100A9 express reduced neutrophil chemokines and are protected from HCC. Inhibiting neutrophil accumulation in CLD or targeting their tumour-promoting activities may offer therapeutic opportunities in HCC.

Activation of Nrf2 Signaling Augments Vesicular Stomatitis Virus Oncolysis via Autophagy-Driven Suppression of Antiviral Immunity.

Science.gov (United States)

Olagnier, David; Lababidi, Rassin R; Hadj, Samar Bel; Sze, Alexandre; Liu, Yiliu; Naidu, Sharadha Dayalan; Ferrari, Matteo; Jiang, Yuan; Chiang, Cindy; Beljanski, Vladimir; Goulet, Marie-Line; Knatko, Elena V; Dinkova-Kostova, Albena T; Hiscott, John; Lin, Rongtuan

2017-08-02

Oncolytic viruses (OVs) offer a promising therapeutic approach to treat multiple types of cancer. In this study, we show that the manipulation of the antioxidant network via transcription factor Nrf2 augments vesicular stomatitis virus Δ51 (VSVΔ51) replication and sensitizes cancer cells to viral oncolysis. Activation of Nrf2 signaling by the antioxidant compound sulforaphane (SFN) leads to enhanced VSVΔ51 spread in OV-resistant cancer cells and improves the therapeutic outcome in different murine syngeneic and xenograft tumor models. Chemoresistant A549 lung cancer cells that display constitutive dominant hyperactivation of Nrf2 signaling are particularly vulnerable to VSVΔ51 oncolysis. Mechanistically, enhanced Nrf2 signaling stimulated viral replication in cancer cells and disrupted the type I IFN response via increased autophagy. This study reveals a previously unappreciated role for Nrf2 in the regulation of autophagy and the innate antiviral response that complements the therapeutic potential of VSV-directed oncolysis against multiple types of OV-resistant or chemoresistant cancer. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

The human microbiome as a reservoir of antimicrobial resistance

Directory of Open Access Journals (Sweden)

John ePenders

2013-04-01

Full Text Available The gut microbiota is amongst the most densely populated microbial ecosystem on earth. While the microbiome exerts numerous health beneficial functions, the high density of microorganisms within this ecosystem also facilitates horizontal transfer of antimicrobial resistance (AMR genes to potential pathogenic bacteria. Over the past decades antibiotic susceptibility testing of specific indicator bacteria from the microbiome, such as Escherichia coli, has been the method of choice in most studies. These studies have greatly enlarged our understanding on the prevalence and distribution of AMR and associated risk factors.Recent studies using (functional metagenomics, however, highlighted the unappreciated diversity of AMR genes in the human microbiome and identified genes that had not been described previously. Next to metagenomics, more targeted approaches such as PCR for detection and quantification of AMR genes within a population are promising, in particular for large-scale epidemiological screening. Here we present an overview of the indigenous microbiota as a reservoir of AMR genes, the current knowledge on this resistome and the recent and upcoming advances in the molecular diagnostic approaches to unravel this reservoir.

IκBζ, an atypical member of the inhibitor of nuclear factor kappa B family, is induced by γ-irradiation in glioma cells, regulating cytokine secretion and associated with poor prognosis.

Science.gov (United States)

Brennenstuhl, Heiko; Armento, Angela; Braczysnki, Anne Kristin; Mittelbronn, Michel; Naumann, Ulrike

2015-11-01

The inhibitor of nuclear factor kappa B zeta (IκBζ) is an atypical member of the IκB protein family. Its function in regulating the activity of the transcription factor nuclear factor kappa B (NFκB) as well as its involvement in cancer-associated processes is poorly understood. In glioma patients, enhanced expression of IκBζ in tumor specimen is associated with poor prognosis. Here we report that IκBζ is upregulated in a glioma cell line resistant towards NFκB-dependent non-apoptotic cell death. Upon γ-irradiation of glioma cells, IκBζ expression is enhanced, and subsequently serves as a transcriptional activator of the tumor promoting cytokines interleukin (IL-6), IL-8 and chemokine (C-X-C motif) ligand 1 (CXCL1) that are known to be involved in glioma associated inflammatory processes. In contrast, shRNA-mediated knockdown of IκBζ reduces the expression of the aforementioned cytokines. We propose a previously unappreciated role of IκBζ in the inflammatory micromilieu as well as progression in glioma.

Perturbation of m6A Writers Reveals Two Distinct Classes of mRNA Methylation at Internal and 5′ Sites

Directory of Open Access Journals (Sweden)

Schraga Schwartz

2014-07-01

Full Text Available N6-methyladenosine (m6A is a common modification of mRNA with potential roles in fine-tuning the RNA life cycle. Here, we identify a dense network of proteins interacting with METTL3, a component of the methyltransferase complex, and show that three of them (WTAP, METTL14, and KIAA1429 are required for methylation. Monitoring m6A levels upon WTAP depletion allowed the definition of accurate and near single-nucleotide resolution methylation maps and their classification into WTAP-dependent and -independent sites. WTAP-dependent sites are located at internal positions in transcripts, topologically static across a variety of systems we surveyed, and inversely correlated with mRNA stability, consistent with a role in establishing “basal” degradation rates. WTAP-independent sites form at the first transcribed base as part of the cap structure and are present at thousands of sites, forming a previously unappreciated layer of transcriptome complexity. Our data shed light on the proteomic and transcriptional underpinnings of this RNA modification.

Requirement of argininosuccinate lyase for systemic nitric oxide production.

Science.gov (United States)

Erez, Ayelet; Nagamani, Sandesh C S; Shchelochkov, Oleg A; Premkumar, Muralidhar H; Campeau, Philippe M; Chen, Yuqing; Garg, Harsha K; Li, Li; Mian, Asad; Bertin, Terry K; Black, Jennifer O; Zeng, Heng; Tang, Yaoping; Reddy, Anilkumar K; Summar, Marshall; O'Brien, William E; Harrison, David G; Mitch, William E; Marini, Juan C; Aschner, Judy L; Bryan, Nathan S; Lee, Brendan

2011-11-13

Nitric oxide (NO) is crucial in diverse physiological and pathological processes. We show that a hypomorphic mouse model of argininosuccinate lyase (encoded by Asl) deficiency has a distinct phenotype of multiorgan dysfunction and NO deficiency. Loss of Asl in both humans and mice leads to reduced NO synthesis, owing to both decreased endogenous arginine synthesis and an impaired ability to use extracellular arginine for NO production. Administration of nitrite, which can be converted into NO in vivo, rescued the manifestations of NO deficiency in hypomorphic Asl mice, and a nitric oxide synthase (NOS)-independent NO donor restored NO-dependent vascular reactivity in humans with ASL deficiency. Mechanistic studies showed that ASL has a structural function in addition to its catalytic activity, by which it contributes to the formation of a multiprotein complex required for NO production. Our data demonstrate a previously unappreciated role for ASL in NOS function and NO homeostasis. Hence, ASL may serve as a target for manipulating NO production in experimental models, as well as for the treatment of NO-related diseases.

A Common Origin for B-1a and B-2 Lymphocytes in Clonal Pre- Hematopoietic Stem Cells.

Science.gov (United States)

Hadland, Brandon K; Varnum-Finney, Barbara; Mandal, Pankaj K; Rossi, Derrick J; Poulos, Michael G; Butler, Jason M; Rafii, Shahin; Yoder, Mervin C; Yoshimoto, Momoko; Bernstein, Irwin D

2017-06-06

Recent evidence points to the embryonic emergence of some tissue-resident innate immune cells, such as B-1a lymphocytes, prior to and independently of hematopoietic stem cells (HSCs). However, whether the full hematopoietic repertoire of embryonic HSCs initially includes these unique lineages of innate immune cells has been difficult to assess due to lack of clonal assays that identify and assess HSC precursor (pre-HSC) potential. Here, by combining index sorting of single embryonic hemogenic precursors with in vitro HSC maturation and transplantation assays, we analyze emerging pre-HSCs at the single-cell level, revealing their unique stage-specific properties and clonal lineage potential. Remarkably, clonal pre-HSCs detected between E9.5 and E11.5 contribute to the complete B cell repertoire, including B-1a lymphocytes, revealing a previously unappreciated common precursor for all B cell lineages at the pre-HSC stage and a second embryonic origin for B-1a lymphocytes. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Mechanical valve assembly for xenon 133 gas delivery systems

Energy Technology Data Exchange (ETDEWEB)

Round, W.H. (Royal Brisbane Hospital, Herston (Australia))

Some gas delivery systems used in pulmonary ventilation scanning are unable to satisfactorily supply /sup 133/Xe gas to bed-ridden patients. A mechanical gas valve assembly to control the flow of gas in such systems was constructed. A commercially produced /sup 133/Xe gas delivery system when fitted with the new assembly was able to ventilate almost all patients whereas previously this could be achieved with approximately only 50% of patients.

Mechanism of carrier-induced ferromagnetism in diluted magnetic semiconductors

International Nuclear Information System (INIS)

Takahashi, M.; Furukawa, N.; Kubo, K.

2004-01-01

Using the spin-polarized band obtained by applying the dynamical coherent potential approximation to a simple model, we have calculated the magnetization of Ga x Mn 1-x As as a function of the temperature for various values of carrier density. The result is consistent with the experimental observation, supporting the view previously proposed by us that the ferromagnetism is induced by the carriers in the bandtail through double-exchange-like mechanism

Origin of choriocarcinoma in previous molar pregnancy proved by DNA analysis

International Nuclear Information System (INIS)

Vojtassak, J.; Repiska, V.; Konecna, B.; Zajac, V.; Korbel, M.; Danihel, L.

1996-01-01

A 17-year old woman had in a short time period (seven months) a very exciting reproduction history. Molar pregnancy in December 1993, choriocarcinoma in January 1994 and induced abortion in June 1994. DNA analysis proved the origin of the choriocarcinoma in the previous molar pregnancy. (author)

Influence of previous knowledge in Torrance tests of creative thinking

OpenAIRE

Aranguren, María; Consejo Nacional de Investigaciones Científicas y Técnicas CONICET

2015-01-01

The aim of this work is to analyze the influence of study field, expertise and recreational activities participation in Torrance Tests of Creative Thinking (TTCT, 1974) performance. Several hypotheses were postulated to explore the possible effects of previous knowledge in TTCT verbal and TTCT figural university students’ outcomes. Participants in this study included 418 students from five study fields: Psychology;Philosophy and Literature, Music; Engineering; and Journalism and Advertisin...

Exploring the MACH Model's Potential as a Metacognitive Tool to Help Undergraduate Students Monitor Their Explanations of Biological Mechanisms

Science.gov (United States)

Trujillo, Caleb M.; Anderson, Trevor R.; Pelaez, Nancy J.

2016-01-01

When undergraduate biology students learn to explain biological mechanisms, they face many challenges and may overestimate their understanding of living systems. Previously, we developed the MACH model of four components used by expert biologists to explain mechanisms: Methods, Analogies, Context, and How. This study explores the implementation of…

Nonlinear Klein-Gordon soliton mechanics

International Nuclear Information System (INIS)

Reinisch, G.

1992-01-01

Nonlinear Klein-Gordon solitary waves - or solitons in a loose sense - in n+1 dimensions, driven by very general external fields which must only satisfy continuity - together with regularity conditions at the boundaries of the system, obey a quite simple equation of motion. This equation is the exact generalization to this dynamical system of infinite number of degrees of freedom - which may be conservative or not - of the second Newton's law setting the basis of material point mechanics. In the restricted case of conservative nonlinear Klein-Gordon systems, where the external driving force is derivable from a potential energy, we recover the generalized Ehrenfest theorem which was itself the extension to such systems of the well-known Ehrenfest theorem in quantum mechanics. This review paper first displays a few (of one-dimensional sine-Gordon type) typical examples of the basic difficulties related to the trial construction of solitary-waves is proved and the derivation of the previous sine-Gordon examples from this theorem is displayed. Two-dimensional nonlinear solitary-wave patterns are considered, as well as a special emphasis is put on the applications to space-time complexity of 1-dim. sine-Gordon systems

Functional toxicogenomic profiling expands insight into modulators of formaldehyde toxicity in yeast

Directory of Open Access Journals (Sweden)

Matthew North

2016-11-01

Full Text Available Formaldehyde (FA is a commercially important chemical with numerous and diverse uses. Accordingly, occupational and environmental exposure to FA is prevalent worldwide. Various adverse effects, including nasopharyngeal, sinonasal, and lymphohematopoietic cancers, have been linked to FA exposure, prompting designation of FA as a human carcinogen by U.S. and international scientific entities. Although the mechanism(s of FA toxicity have been well studied, additional insight is needed in regard to the genetic requirements for FA tolerance. In this study, a functional toxicogenomics approach was utilized in the model eukaryotic yeast Saccharomyces cerevisiae to identify genes and cellular processes modulating the cellular toxicity of FA. Our results demonstrate mutant strains deficient in multiple DNA repair pathways–including homologous recombination, single strand annealing, and postreplication repair–were sensitive to FA, indicating FA may cause various forms of DNA damage in yeast. The SKI complex and its associated factors, which regulate mRNA degradation by the exosome, were also required for FA tolerance, suggesting FA may have unappreciated effects on RNA stability. Furthermore, various strains involved in osmoregulation and stress response were sensitive to FA. Together, our results are generally consistent with FA-mediated damage to both DNA and RNA. Considering DNA repair and RNA degradation pathways are evolutionarily conserved from yeast to humans, mechanisms of FA toxicity identified in yeast may be relevant to human disease and genetic susceptibility.

Development of Pipe Holding Mechanism for Pipe Inspection Robot Using Flexible Pneumatic Cylinder

Directory of Open Access Journals (Sweden)

Choi Kyujun

2016-01-01

Full Text Available A pipe inspection robot is useful to reduce the inspection cost. In the previous study, a novel pipe inspection robot using a flexible pneumatic cylinder that can move forward along to the pipe by changing the robot’s body naturally was proposed and tested. In this paper, to improve its mobility for a corner of a pipe, the thin pipe holding mechanism using pneumatic bellows was proposed and tested. As a result of its driving test, the holding performance of the mechanism was confirmed.

Validation of the Online version of the Previous Day Food Questionnaire for schoolchildren

Directory of Open Access Journals (Sweden)

Raquel ENGEL

Full Text Available ABSTRACT Objective To evaluate the validity of the web-based version of the Previous Day Food Questionnaire Online for schoolchildren from the 2nd to 5th grades of elementary school. Methods Participants were 312 schoolchildren aged 7 to 12 years of a public school from the city of Florianópolis, Santa Catarina, Brazil. Validity was assessed by sensitivity, specificity, as well as by agreement rates (match, omission, and intrusion rates of food items reported by children on the Previous Day Food Questionnaire Online, using direct observation of foods/beverages eaten during school meals (mid-morning snack or afternoon snack on the previous day as the reference. Multivariate multinomial logistic regression analysis was used to evaluate the influence of participants’ characteristics on omission and intrusion rates. Results The results showed adequate sensitivity (67.7% and specificity (95.2%. There were low omission and intrusion rates of 22.8% and 29.5%, respectively when all food items were analyzed. Pizza/hamburger showed the highest omission rate, whereas milk and milk products showed the highest intrusion rate. The participants who attended school in the afternoon shift presented a higher probability of intrusion compared to their peers who attended school in the morning. Conclusion The Previous Day Food Questionnaire Online possessed satisfactory validity for the assessment of food intake at the group level in schoolchildren from the 2nd to 5th grades of public school.

Unraveling the Mechanisms of Manual Therapy: Modeling an Approach.

Science.gov (United States)

Bialosky, Joel E; Beneciuk, Jason M; Bishop, Mark D; Coronado, Rogelio A; Penza, Charles W; Simon, Corey B; George, Steven Z

2018-01-01

Synopsis Manual therapy interventions are popular among individual health care providers and their patients; however, systematic reviews do not strongly support their effectiveness. Small treatment effect sizes of manual therapy interventions may result from a "one-size-fits-all" approach to treatment. Mechanistic-based treatment approaches to manual therapy offer an intriguing alternative for identifying patients likely to respond to manual therapy. However, the current lack of knowledge of the mechanisms through which manual therapy interventions inhibit pain limits such an approach. The nature of manual therapy interventions further confounds such an approach, as the related mechanisms are likely a complex interaction of factors related to the patient, the provider, and the environment in which the intervention occurs. Therefore, a model to guide both study design and the interpretation of findings is necessary. We have previously proposed a model suggesting that the mechanical force from a manual therapy intervention results in systemic neurophysiological responses leading to pain inhibition. In this clinical commentary, we provide a narrative appraisal of the model and recommendations to advance the study of manual therapy mechanisms. J Orthop Sports Phys Ther 2018;48(1):8-18. doi:10.2519/jospt.2018.7476.

Challenges for the Nelson-Barr mechanism

International Nuclear Information System (INIS)

Dine, Michael; Draper, Patrick

2015-01-01

The axion and m u =0 solutions to the strong CP problem have been subject to the most careful scrutiny and critique. Basic theoretical issues include hierarchy and fine-tuning problems, quality and genericity of symmetries, and compatibility with solutions to the electroweak hierarchy problem. We study the similar set of challenges for solutions to strong CP based on spontaneous CP violation and the Nelson-Barr mechanism. Some of our observations have appeared in the literature previously, and others are new; our purpose is to collect and analyze the issues as a whole and provide an assessment of the most plausible settings for the Nelson-Barr solution.

A cross-culture, cross-gender comparison of perspective taking mechanisms.

Science.gov (United States)

Kessler, Klaus; Cao, Liyu; O'Shea, Kieran J; Wang, Hongfang

2014-06-22

Being able to judge another person's visuo-spatial perspective is an essential social skill, hence we investigated the generalizability of the involved mechanisms across cultures and genders. Developmental, cross-species, and our own previous research suggest that two different forms of perspective taking can be distinguished, which are subserved by two distinct mechanisms. The simpler form relies on inferring another's line-of-sight, whereas the more complex form depends on embodied transformation into the other's orientation in form of a simulated body rotation. Our current results suggest that, in principle, the same basic mechanisms are employed by males and females in both, East-Asian (EA; Chinese) and Western culture. However, we also confirmed the hypothesis that Westerners show an egocentric bias, whereas EAs reveal an other-oriented bias. Furthermore, Westerners were slower overall than EAs and showed stronger gender differences in speed and depth of embodied processing. Our findings substantiate differences and communalities in social cognition mechanisms across genders and two cultures and suggest that cultural evolution or transmission should take gender as a modulating variable into account.

Tuning Cell and Tissue Development by Combining Multiple Mechanical Signals.

Science.gov (United States)

Sinha, Ravi; Verdonschot, Nico; Koopman, Bart; Rouwkema, Jeroen

2017-10-01

Mechanical signals offer a promising way to control cell and tissue development. It has been established that cells constantly probe their mechanical microenvironment and employ force feedback mechanisms to modify themselves and when possible, their environment, to reach a homeostatic state. Thus, a correct mechanical microenvironment (external forces and mechanical properties and shapes of cellular surroundings) is necessary for the proper functioning of cells. In vitro or in the case of nonbiological implants in vivo, where cells are in an artificial environment, addition of the adequate mechanical signals can, therefore, enable the cells to function normally as in vivo. Hence, a wide variety of approaches have been developed to apply mechanical stimuli (such as substrate stretch, flow-induced shear stress, substrate stiffness, topography, and modulation of attachment area) to cells in vitro. These approaches have not just revealed the effects of the mechanical signals on cells but also provided ways for probing cellular molecules and structures that can provide a mechanistic understanding of the effects. However, they remain lower in complexity compared with the in vivo conditions, where the cellular mechanical microenvironment is the result of a combination of multiple mechanical signals. Therefore, combinations of mechanical stimuli have also been applied to cells in vitro. These studies have had varying focus-developing novel platforms to apply complex combinations of mechanical stimuli, observing the co-operation/competition between stimuli, combining benefits of multiple stimuli toward an application, or uncovering the underlying mechanisms of their action. In general, they provided new insights that could not have been predicted from previous knowledge. We present here a review of several such studies and the insights gained from them, thereby making a case for such studies to be continued and further developed.

[Parathyroid cancer in a patient with previous history of hypernephroma: a clinical case].

Science.gov (United States)

Martín Navarro, J; Mendoza, E; Mateos, P; Cereceda, A; Coca, S

2007-01-01

We report the clinical case of a 55 year-old male patient, with a previous history of nephrectomy by hypernephroma sixteen years ago, first presenting hypercalcemia and rising of intact parathyroid hormone (iPTH) levels. A localization study revealed an intrathyroid nodule with cystic appearance. After undergoing a hemi-thyroidectomy, the patient is diagnosed with parathyroid carcinoma. This article analyzes previously published cases presenting parathyroidal pathologies associated with hypernephroma. A broader differential diagnosis--including the screening of parathyroidal pathologies should be considered in patients with hypercalcemia and hypernephroma.

Capabilities and Limitations of Tissue Size Control through Passive Mechanical Forces.

Directory of Open Access Journals (Sweden)

Jochen Kursawe

2015-12-01

Full Text Available Embryogenesis is an extraordinarily robust process, exhibiting the ability to control tissue size and repair patterning defects in the face of environmental and genetic perturbations. The size and shape of a developing tissue is a function of the number and size of its constituent cells as well as their geometric packing. How these cellular properties are coordinated at the tissue level to ensure developmental robustness remains a mystery; understanding this process requires studying multiple concurrent processes that make up morphogenesis, including the spatial patterning of cell fates and apoptosis, as well as cell intercalations. In this work, we develop a computational model that aims to understand aspects of the robust pattern repair mechanisms of the Drosophila embryonic epidermal tissues. Size control in this system has previously been shown to rely on the regulation of apoptosis rather than proliferation; however, to date little work has been done to understand the role of cellular mechanics in this process. We employ a vertex model of an embryonic segment to test hypotheses about the emergence of this size control. Comparing the model to previously published data across wild type and genetic perturbations, we show that passive mechanical forces suffice to explain the observed size control in the posterior (P compartment of a segment. However, observed asymmetries in cell death frequencies across the segment are demonstrated to require patterning of cellular properties in the model. Finally, we show that distinct forms of mechanical regulation in the model may be distinguished by differences in cell shapes in the P compartment, as quantified through experimentally accessible summary statistics, as well as by the tissue recoil after laser ablation experiments.

Streptococcus agalactiae endocarditis presenting as acalculous cholecystitis in a previously well woman.

LENUS (Irish Health Repository)

Brewer, Linda

2013-01-01

This case report describes the unusual presentation of a previously very well woman with Streptococcus agalactiae endocarditis in the emergency department. History, examination and preliminary laboratory and radiological investigations supported a diagnosis of acalculous cholecystitis, for which she was given intravenous broad spectrum antimicrobial therapy. One day following admission, the patient deteriorated and became unresponsive. Subsequent MRI of the brain revealed multiple bihemispheric cerebral emboli and a large, mobile mitral valve thrombus was visualised on her transoesophageal echocardiogram. S agalactiae was cultured from venous blood samples and her antimicrobial cover was adjusted accordingly. Despite her presumed guarded prognosis, this patient made a remarkable recovery. To our knowledge, the association of S agalactiae endocarditis with acalculous cholecystitis has not been previously described.

Granulomatous lobular mastitis: report of a case with previously undescribed histopathological abnormalities.

Science.gov (United States)

Axelsen, R A; Reasbeck, P

1988-10-01

A 41-yr-old multiparous woman presented with a discrete breast lump which proved histologically to be an example of granulomatous lobular mastitis. The clinical and histological features were similar to those noted in previous reports. Additional histological features in the present case were an intense mononuclear cell infiltration of lobular and ductal epithelium, associated with nuclear fragments morphologically suggestive of apoptosis. These appearances, which have not previously been described, are illustrated, together with the more classical features of the condition well demonstrated by the present case. The novel histological features noted here suggest that the development of granulomatous lobular mastitis may be at least in part immunologically mediated, and that the cellular infiltrates seen may be a manifestation of cell-mediated destruction of mammary epithelium.

High mechanical advantage design of six-bar Stephenson mechanism for servo mechanical presses

Directory of Open Access Journals (Sweden)

Jianguo Hu

2016-06-01

Full Text Available This article proposed a two-phase design scheme of Stephenson six-bar working mechanisms for servo mechanical presses with high mechanical advantage. In the qualitative design phase, first, a Stephenson six-bar mechanism with a slide was derived from Stephenson six-bar kinematic chains. Second, based on the instant center analysis method, the relationship between mechanical advantage and some special instant centers was founded, and accordingly a primary mechanism configuration with high mechanical advantage was designed qualitatively. Then, a parameterized prototype model was established, and the influences of design parameters toward slide kinematical characteristics were analyzed. In the quantitative design phase, a multi-objective optimization model, aiming at high mechanical advantage and dwelling characteristics, was built, and a case design was done to find optimal dimensions. Finally, simulations based on the software ADAMS were conducted to compare the transmission characteristics of the optimized working mechanism with that of slide-crank mechanism and symmetrical toggle mechanism, and an experimental press was made to validate the design scheme. The simulation and experiment results show that, compared with general working mechanisms, the Stephenson six-bar working mechanism has higher mechanical advantage and better dwelling characteristics, reducing capacities and costs of servo motors effectively.

Initial results of CyberKnife treatment for recurrent previously irradiated head and neck cancer

International Nuclear Information System (INIS)

Himei, Kengo; Katsui, Kuniaki; Yoshida, Atsushi

2003-01-01

The purpose of this study was to evaluate the efficacy of CyberKnife for recurrent previously irradiated head and neck cancer. Thirty-one patients with recurrent previously irradiated head and neck cancer were treated with a CyberKnife from July 1999 to March 2002 at Okayama Kyokuto Hospital were retrospectively studied. The accumulated dose was 28-80 Gy (median 60 Gy). The interval between CyberKnife treatment and previous radiotherapy was 0.4-429.5 months (median 16.3 months). Primary lesions were nasopharynx: 7, maxillary sinus: 6, tongue: 5, ethmoid sinus: 3, and others: 1. The pathology was squamous cell carcinoma: 25, adenoid cystic carcinoma: 4, and others: 2. Symptoms were pain: 8, and nasal bleeding: 2. The prescribed dose was 15.0-40.3 Gy (median 32.3 Gy) as for the marginal dose. The response rate (complete response (CR)+partial response (PR)) and local control rate (CR+PR+no change (NC)) was 74% and 94% respectively. Pain disappeared for 4 cases, relief was obtained for 4 cases and no change for 2 cases and nasal bleeding disappeared for 2 cases for an improvement of symptoms. An adverse effects were observed as mucositis in 5 cases and neck swelling in one case. Prognosis of recurrent previously irradiated head and neck cancer was estimated as poor. Our early experience shows that CyberKnife is expected to be feasible treatment for recurrent previously irradiated head and neck cancer, and for the reduction adverse effects and maintenance of useful quality of life (QOL) for patients. (author)

Unraveling the differences of the hydrolytic activity of Trypanosoma cruzi trans-sialidase and Trypanosoma rangeli sialidase: a quantum mechanics-molecular mechanics modeling study.

Science.gov (United States)

Bueren-Calabuig, Juan A; Pierdominici-Sottile, Gustavo; Roitberg, Adrian E

2014-06-05

Chagas' disease, also known as American trypanosomiasis, is a lethal, chronic disease that currently affects more than 10 million people in Central and South America. The trans-sialidase from Trypanosoma cruzi (T. cruzi, TcTS) is a crucial enzyme for the survival of this parasite: sialic acids from the host are transferred to the cell surface glycoproteins of the trypanosome, thereby evading the host's immune system. On the other hand, the sialidase of T. rangeli (TrSA), which shares 70% sequence identity with TcTS, is a strict hydrolase and shows no trans-sialidase activity. Therefore, TcTS and TrSA represent an excellent framework to understand how different catalytic activities can be achieved with extremely similar structures. By means of combined quantum mechanics-molecular mechanics (QM/MM, SCC-DFTB/Amberff99SB) calculations and umbrella sampling simulations, we investigated the hydrolysis mechanisms of TcTS and TrSA and computed the free energy profiles of these reactions. The results, together with our previous computational investigations, are able to explain the catalytic mechanism of sialidases and describe how subtle differences in the active site make TrSA a strict hydrolase and TcTS a more efficient trans-sialidase.

A New and Versatile Adjustable Rigidity Actuator with Add-on Locking Mechanism (ARES-XL

Directory of Open Access Journals (Sweden)

Manuel Cestari

2018-01-01

Full Text Available Adjustable compliant actuators are being designed and implemented in robotic devices because of their ability to minimize large forces due to impacts, to safely interact with the user, and to store and release energy in passive elastic elements. Conceived as a new force-controlled compliant actuator, an adjustable rigidity with embedded sensor and locking mechanism actuator (ARES-XL is presented in this paper. This compliant system is intended to be implemented in a gait exoskeleton for children with neuro muscular diseases (NMDs to exploit the intrinsic dynamics during locomotion. This paper describes the mechanics and initial evaluation of the ARES-XL, a novel variable impedance actuator (VIA that allows the implementation of an add-on locking mechanism to this system, and in combination with its zero stiffness capability and large deflection range, provides this novel joint with improved properties when compared to previous prototypes developed by the authors and other state-of-the-art (SoA devices. The evaluation of the system proves how this design exceeds the main capabilities of a previous prototype as well as providing versatile actuation that could lead to its implementation in multiple joints.

Pulmonary Aspergillosis in a Previously Healthy 13-Year-Old Boy

Directory of Open Access Journals (Sweden)

Jonathan H. Rayment

2016-01-01

Full Text Available Chronic granulomatous disease (CGD is a rare, polygenic primary immunodeficiency. In this case report, we describe a previously healthy 13-year-old boy who presented with multifocal pulmonary aspergillosis and was subsequently diagnosed with an autosomal recessive form of chronic granulomatous disease. CGD has a variable natural history and age of presentation and should be considered when investigating a patient with recurrent or severe infections with catalase-positive organisms.

Pore direction in relation to anisotropy of mechanical strength in a cubic starch compact

NARCIS (Netherlands)

Wu, Yu San; van Vliet, Lucas J; Frijlink, Henderik W; Stokroos, Ietse; van der Voort Maarschalk, Kees

The purpose of this research was to evaluate the relation between preferential direction of pores and mechanical strength of cubic starch compacts. The preferential pore direction was quantified in SEM images of cross sections of starch compacts using a previously described algorithm for

[Meningitis and white matter lesions due to Streptococcus mitis in a previously healthy child].

Science.gov (United States)

Yiş, Reyhan; Yüksel, Ciğdem Nükhet; Derundere, Umit; Yiş, Uluç

2011-10-01

Streptococcus mitis, an important member of viridans streptococci, is found in the normal flora of the oropharynx, gastrointestinal tract, female genital tract and skin. Although it is of low pathogenicity and virulence, it may cause serious infections in immunocompromised patients. Meningitis caused by S.mitis has been described in patients with previous spinal anesthesia, neurosurgical procedure, malignancy, bacterial endocarditis with neurological complications and alcoholics, but it is rare in patients who are previously healthy. In this report, a rare case of meningoencephalitis caused by S.mitis developed in a previously healthy child has been presented. A previously healthy eight-year-old girl who presented with fever, altered state of consciousness, and headache was hospitalized in intensive care unit with the diagnosis of meningitis. Past history revealed that she was treated with amoxicillin-clavulanate for acute sinusitis ten days before her admission. Whole blood count revealed the followings: hemoglobin 13 g/dl, white blood cell count 18.6 x 109/L (90% neutrophils), platelet count 200 x 109/L and 150 leucocytes were detected on cerebrospinal fluid (CSF) examination. Protein and glucose levels of CSF were 80 mg/dl and 40 mg/dl (concomitant blood glucose 100 mg/dl), respectively. Brain magnetic resonance imaging (MRI) revealed widespread white matter lesions, and alpha-hemolytic streptococci were grown in CSF culture. The isolate was identified as S.mitis with conventional methods, and also confirmed by VITEK2 (bioMerieux, France) and API 20 STREP (bioMerieux, France) systems. Isolate was found susceptible to penicillin, erythromycin, clindamycin, tetracycline, cefotaxime, vancomycin and chloramphenicol. Regarding the etiology, echocardiography revealed no vegetation nor valve pathology, and peripheral blood smear showed no abnormality. Immunoglobulin and complement levels were within normal limits. Ongoing inflammation in maxillary sinuses detected in

Predictive effects of previous episodes on the risk of recurrence in depressive and bipolar disorders

DEFF Research Database (Denmark)

Kessing, Lars Vedel; Andersen, Per Kragh

2005-01-01

Findings from several studies have suggested that the risk of recurrence increases with the number of previous episodes in depressive and bipolar disorders. However, a comprehensive and critical review of the literature published during the past century shows that in several previous studies...

Virus epidemics can lead to a population-wide spread of intragenomic parasites in a previously parasite-free asexual population.

Science.gov (United States)

Jalasvuori, Matti; Lehtonen, Jussi

2014-03-01

Sexual reproduction is problematic to explain due to its costs, most notably the twofold cost of sex. Yet, sex has been suggested to be favourable in the presence of proliferating intragenomic parasites given that sexual recombination provides a mechanism to confine the accumulation of deleterious mutations. Kraaijeveld et al. compared recently the accumulation of transposons in sexually and asexually reproducing lines of the same species, the parasitoid wasp Leptopilina clavipes. They discovered that within asexually reproducing wasps, the number of gypsy-like retrotransposons was increased fourfold, whereas other retrotransposons were not. Interestingly, gypsy-like retrotransposons are closely related to retroviruses. Endogenous retroviruses are retroviruses that have integrated to the germ line cells and are inherited thereafter vertically. They can also replicate within the genome similarly to retrotransposons as well as form virus particles and infect previously uninfected cells. This highlights the possibility that endogenous retroviruses could play a role in the evolution of sexual reproduction. Here, we show with an individual-based computational model that a virus epidemic within a previously parasite-free asexual population may establish a new intragenomic parasite to the population. Moreover and in contrast to other transposons, the possibility of endogenous viruses to maintain a virus epidemic and simultaneously provide resistance to individuals carrying active endogenous viruses selects for the presence of active intragenomic parasites in the population despite their deleterious effects. Our results suggest that the viral nature of certain intragenomic parasites should be taken into account when sex and its benefits are being considered. © 2014 John Wiley & Sons Ltd.

Establishment of neurovascular congruency in the mouse whisker system by an independent patterning mechanism.

Science.gov (United States)

Oh, Won-Jong; Gu, Chenghua

2013-10-16

Nerves and vessels often run parallel to one another, a phenomenon that reflects their functional interdependency. Previous studies have suggested that neurovascular congruency in planar tissues such as skin is established through a "one-patterns-the-other" model, in which either the nervous system or the vascular system precedes developmentally and then instructs the other system to form using its established architecture as a template. Here, we find that, in tissues with complex three-dimensional structures such as the mouse whisker system, neurovascular congruency does not follow the previous model but rather is established via a mechanism in which nerves and vessels are patterned independently. Given the diversity of neurovascular structures in different tissues, guidance signals emanating from a central organizer in the specific target tissue may act as an important mechanism to establish neurovascular congruency patterns that facilitate unique target tissue function. Copyright © 2013 Elsevier Inc. All rights reserved.

Experimental study and constitutive modeling of the viscoelastic mechanical properties of the human prolapsed vaginal tissue.

Science.gov (United States)

Peña, Estefania; Calvo, B; Martínez, M A; Martins, P; Mascarenhas, T; Jorge, R M N; Ferreira, A; Doblaré, M

2010-02-01

In this paper, the viscoelastic mechanical properties of vaginal tissue are investigated. Using previous results of the authors on the mechanical properties of biological soft tissues and newly experimental data from uniaxial tension tests, a new model for the viscoelastic mechanical properties of the human vaginal tissue is proposed. The structural model seems to be sufficiently accurate to guarantee its application to prediction of reliable stress distributions, and is suitable for finite element computations. The obtained results may be helpful in the design of surgical procedures with autologous tissue or prostheses.

A continuum mechanics-based musculo-mechanical model for esophageal transport

Science.gov (United States)

Kou, Wenjun; Griffith, Boyce E.; Pandolfino, John E.; Kahrilas, Peter J.; Patankar, Neelesh A.

2017-11-01

In this work, we extend our previous esophageal transport model using an immersed boundary (IB) method with discrete fiber-based structural model, to one using a continuum mechanics-based model that is approximated based on finite elements (IB-FE). To deal with the leakage of flow when the Lagrangian mesh becomes coarser than the fluid mesh, we employ adaptive interaction quadrature points to deal with Lagrangian-Eulerian interaction equations based on a previous work (Griffith and Luo [1]). In particular, we introduce a new anisotropic adaptive interaction quadrature rule. The new rule permits us to vary the interaction quadrature points not only at each time-step and element but also at different orientations per element. This helps to avoid the leakage issue without sacrificing the computational efficiency and accuracy in dealing with the interaction equations. For the material model, we extend our previous fiber-based model to a continuum-based model. We present formulations for general fiber-reinforced material models in the IB-FE framework. The new material model can handle non-linear elasticity and fiber-matrix interactions, and thus permits us to consider more realistic material behavior of biological tissues. To validate our method, we first study a case in which a three-dimensional short tube is dilated. Results on the pressure-displacement relationship and the stress distribution matches very well with those obtained from the implicit FE method. We remark that in our IB-FE case, the three-dimensional tube undergoes a very large deformation and the Lagrangian mesh-size becomes about 6 times of Eulerian mesh-size in the circumferential orientation. To validate the performance of the method in handling fiber-matrix material models, we perform a second study on dilating a long fiber-reinforced tube. Errors are small when we compare numerical solutions with analytical solutions. The technique is then applied to the problem of esophageal transport. We use two

Quantum chemical aided prediction of the thermal decomposition mechanisms and temperatures of ionic liquids

International Nuclear Information System (INIS)

Kroon, Maaike C.; Buijs, Wim; Peters, Cor J.; Witkamp, Geert-Jan

2007-01-01

The long-term thermal stability of ionic liquids is of utmost importance for their industrial application. Although the thermal decomposition temperatures of various ionic liquids have been measured previously, experimental data on the thermal decomposition mechanisms and kinetics are scarce. It is desirable to develop quantitative chemical tools that can predict thermal decomposition mechanisms and temperatures (kinetics) of ionic liquids. In this work ab initio quantum chemical calculations (DFT-B3LYP) have been used to predict thermal decomposition mechanisms, temperatures and the activation energies of the thermal breakdown reactions. These quantum chemical calculations proved to be an excellent method to predict the thermal stability of various ionic liquids

High Resolution Transmission Electron Microscope Observation of Zero-Strain Deformation Twinning Mechanisms in Ag

Science.gov (United States)

Liu, L.; Wang, J.; Gong, S. K.; Mao, S. X.

2011-04-01

We have observed a new deformation-twinning mechanism using the high resolution transmission electron microscope in polycrystalline Ag films, zero-strain twinning via nucleation, and the migration of a Σ3{112} incoherent twin boundary (ITB). This twinning mechanism produces a near zero macroscopic strain because the net Burgers vectors either equal zero or are equivalent to a Shockley partial dislocation. This observation provides new insight into the understanding of deformation twinning and confirms a previous hypothesis: detwinning could be accomplished via the nucleation and migration of Σ3{112} ITBs. The zero-strain twinning mechanism may be unique to low staking fault energy metals with implications for their deformation behavior.

Programmable Self-Locking Origami Mechanical Metamaterials.

Science.gov (United States)

Fang, Hongbin; Chu, Shih-Cheng A; Xia, Yutong; Wang, Kon-Well

2018-04-01

Developing mechanical metamaterials with programmable properties is an emerging topic receiving wide attention. While the programmability mainly originates from structural multistability in previously designed metamaterials, here it is shown that nonflat-foldable origami provides a new platform to achieve programmability via its intrinsic self-locking and reconfiguration capabilities. Working with the single-collinear degree-4 vertex origami tessellation, it is found that each unit cell can self-lock at a nonflat configuration and, therefore, possesses wide design space to program its foldability and relative density. Experiments and numerical analyses are combined to demonstrate that by switching the deformation modes of the constituent cell from prelocking folding to postlocking pressing, its stiffness experiences a sudden jump, implying a limiting-stopper effect. Such a stiffness jump is generalized to a multisegment piecewise stiffness profile in a multilayer model. Furthermore, it is revealed that via strategically switching the constituent cells' deformation modes through passive or active means, the n-layer metamaterial's stiffness is controllable among 2 n target stiffness values. Additionally, the piecewise stiffness can also trigger bistable responses dynamically under harmonic excitations, highlighting the metamaterial's rich dynamic performance. These unique characteristics of self-locking origami present new paths for creating programmable mechanical metamaterials with in situ controllable mechanical properties. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantum physics, fuzzy sets and logic steps towards a many-valued interpretation of quantum mechanics

CERN Document Server

Pykacz, Jarosław

2015-01-01

This Brief presents steps towards elaborating a new interpretation of quantum mechanics based on a specific version of Łukasiewicz infinite-valued logic. It begins with a short survey of main interpretations of quantum mechanics already proposed, as well as various models of many-valued logics and previous attempts to apply them for the description of quantum phenomena. The prospective many-valued interpretation of quantum mechanics is soundly based on a theorem concerning the isomorphic representation of Birkhoff-von Neumann quantum logic in the form of a special Łukasiewicz infinite-valued logic endowed with partially defined conjunctions and disjunctions.

Mechanical Tensile Testing of Titanium 15-3-3-3 and Kevlar 49 at Cryogenic Temperatures

Science.gov (United States)

James, Bryan L.; Martinez, Raul M.; Shirron, Peter; Tuttle, Jim; Galassi, Nicholas M.; Mcguinness, Daniel S.; Puckett, David; Francis, John J.; Flom, Yury

2011-01-01

Titanium 15-3-3-3 and Kevlar 49 are highly desired materials for structural components in cryogenic applications due to their low thennal conductivity at low temperatures. Previous tests have indicated that titanium 15-3-3-3 becomes increasingly brittle as the temperature decreases. Furthermore, little is known regarding the mechanical properties of Kevlar 49 at low temperatures, most specifically its Young's modulus. This testing investigates the mechanical properties of both materials at cryogenic temperatures through cryogenic mechanical tensile testing to failure. The elongation, ultimate tensile strength, yield strength, and break strength of both materials are provided and analyzed here.

New transformation mechanism for a zinc-blende to rocksalt phase transformation in MgS

International Nuclear Information System (INIS)

Durandurdu, Murat

2009-01-01

The stability of the zinc-blende structured MgS is studied using a constant pressure ab initio molecular dynamics technique. A phase transition into a rocksalt structure is observed through the simulation. The zinc-blende to rocksalt phase transformation proceeds via two rhombohedral intermediate phases within R3m (No:160) and R3-barm (No:166) symmetries and does not involve any bond breaking. This mechanism is different from the previously observed mechanism in molecular dynamics simulations. (fast track communication)

Memory and food intake in sheep: Effects of previous exposure to ...

African Journals Online (AJOL)

Animal behaviour pattern was monitored once every 5 min, over an 8-h period, immediately after first confinement. Frequency of eating, idling, ruminating, or drinking were all found to be significantly greater (P<0.001) for previously exposed lambs. Intakes of OM, N, DOM, and leaf fraction in straw were also significantly ...

Retrospective analysis on malignant calcification previously misdiagnosed as benign on screening mammography

International Nuclear Information System (INIS)

Ha, Su Min; Cha, Joo Hee; Kim, Hak Hee; Shin, Hee Jung; Chae, Eun Young; Choi, Woo Jung

2017-01-01

The purpose of our study was to investigate the morphology and distribution of calcifications initially interpreted as benign or probably benign, but proven to be malignant by subsequent stereotactic biopsy, and to identify the reason for misinterpretation or underestimation at the initial diagnosis. Out of 567 women who underwent stereotactic biopsy for calcifications at our hospital between January 2012 and December 2014, 167 women were diagnosed with malignancy. Forty-six of these 167 women had previous mammography assessed as benign or probably benign which was changed to suspicious malignancy on follow-up mammography. Of these 46 women, three women with biopsy-proven benign calcifications at the site of subsequent cancer were excluded, and 43 patients were finally included. The calcifications (morphology, distribution, extent, associated findings) in the previous and follow-up mammography examinations were analyzed according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon and assessment category. We classified the patients into two groups: 1) group A patients who were still retrospectively re-categorized as less than or equal to BI-RADS 3 and 2) group B patients who were re-categorized as equal to or higher than BI-RADS 4a and whose results should have prompted previous diagnostic assessment. In the follow-up mammography examinations, change in calcification morphology (n = 27, 63%) was the most frequent cause of assessment change. The most frequent previous mammographic findings of malignant calcification were amorphous morphology (n = 26, 60%) and grouped distribution (n = 36, 84%). The most frequent calcification findings at reassessment were amorphous morphology (n = 4, 9%), fine pleomorphic calcification (n = 30, 70%), grouped distribution (n = 23, 53%), and segmental calcification (n = 12, 28%). There were 33 (77%) patients in group A, and 10 patients (23%) in group B. Amorphous morphology and grouped distribution were the most frequent

Retrospective analysis on malignant calcification previously misdiagnosed as benign on screening mammography

Energy Technology Data Exchange (ETDEWEB)

Ha, Su Min [Dept. of Radiology, Research Institute of Radiology, Chung Ang University Hospital, Seoul(Korea, Republic of); Cha, Joo Hee; Kim, Hak Hee; Shin, Hee Jung; Chae, Eun Young; Choi, Woo Jung [Dept. of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

2017-04-15

The purpose of our study was to investigate the morphology and distribution of calcifications initially interpreted as benign or probably benign, but proven to be malignant by subsequent stereotactic biopsy, and to identify the reason for misinterpretation or underestimation at the initial diagnosis. Out of 567 women who underwent stereotactic biopsy for calcifications at our hospital between January 2012 and December 2014, 167 women were diagnosed with malignancy. Forty-six of these 167 women had previous mammography assessed as benign or probably benign which was changed to suspicious malignancy on follow-up mammography. Of these 46 women, three women with biopsy-proven benign calcifications at the site of subsequent cancer were excluded, and 43 patients were finally included. The calcifications (morphology, distribution, extent, associated findings) in the previous and follow-up mammography examinations were analyzed according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon and assessment category. We classified the patients into two groups: 1) group A patients who were still retrospectively re-categorized as less than or equal to BI-RADS 3 and 2) group B patients who were re-categorized as equal to or higher than BI-RADS 4a and whose results should have prompted previous diagnostic assessment. In the follow-up mammography examinations, change in calcification morphology (n = 27, 63%) was the most frequent cause of assessment change. The most frequent previous mammographic findings of malignant calcification were amorphous morphology (n = 26, 60%) and grouped distribution (n = 36, 84%). The most frequent calcification findings at reassessment were amorphous morphology (n = 4, 9%), fine pleomorphic calcification (n = 30, 70%), grouped distribution (n = 23, 53%), and segmental calcification (n = 12, 28%). There were 33 (77%) patients in group A, and 10 patients (23%) in group B. Amorphous morphology and grouped distribution were the most frequent

Modeling mechanical and thermo-mechanical erosion by flowing lava at Raglan, Cape Smith Belt, New Québec, Canada

Science.gov (United States)

Cataldo, V.; Williams, D. A.; Lesher, C. M.

2015-12-01

The 1.5-D Williams et al. model of thermal erosion by turbulent lava was recently applied to the Athabasca Valles lava channel on Mars, in an attempt to establish the importance of thermal erosion in excavating this ~80-100 m deep outflow channel. The modeled erosion depths (0.4-7.5 m) are far less than the depth of the channel which, combined with the short duration of the eruption, suggests that mechanical erosion may have had a greater role. Several studies suggest that mechanical erosion by lava is more important in channel-tube formation than previously thought, under certain circumstances. How would we be able to distinguish between mechanical and thermal erosion? By investigating model results when substrate properties change, as we move from a consolidated, mechanically strong substrate to a partially consolidated or unconsolidated, mechanically weaker substrate. The Proterozoic Raglan komatiitic basalt lava channel of the Cape Smith Belt, New Québec, Canada is a complex erosional environment involving invasive erosion of both sediment and gabbro substrates - which makes it a critical test case. The lava eroded an upper layer of soft sediment, with erosion at the tops, bottoms, and sides of the conduit, through underlying gabbro, and then burrowed laterally into underlying sediment, a scenario requiring a two-dimensional modeling approach. Using the available field data, we will simulate two-dimensional thermomechanical and mechanical erosion interfaces on all sides of a turbulent lava flow by creating a finite-element mesh. The mesh will be defined by the geometry of the lava flow at those lava conduits for which data on lava and substrate composition, lava thickness, slope of the ground, conduit area and volume, and lava flow length are available. Ultimately, this model will be applied to lunar sinuous rilles and martian lava channels for which the use of a two-dimensional approach is needed.

Fiscal 1981 Sunshine Project research report. Research on underground reinjection mechanism of hot water; 1981 nendo nessui no chika kangen mechanism no chosa kenkyu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1982-03-01

This report summarizes the fiscal 1981 research result on the behavior and flow mechanism of underground reinjected hot water, and the effect of reinjected hot water on the ground. In the tracer survey in Takinoue area, Iwate prefecture, the re-upwelling rate and mixing rate of reinjected hot water were lower than those in previous surveys, showing the smaller effect of hot water on productivity. In Nigori-Gawa area, Hokkaido, natural conditions prior to industrial production and reinjection were observed by tracer survey. In the simulation research, it was confirmed that the hydraulic structural model and analysis technique established by previous researches are effective for new production and reinjection systems different from previous ones enough. On observation of minute earthquakes, study was made on the effect of reinjected hot water on the ground in Takinoue area. In Nigori-Gawa area, the data were collected under natural conditions prior to industrial production and reinjection through minute earthquake observations. (NEDO)

Obsah a pozice copywritingu v životním cyklu webu

OpenAIRE

Přikryl, Jan

2009-01-01

Main purpose of this thesis based on analysis, searching and synthesis of accessible sources is to describe web copywriter's role concerning content, to position copywriting into web life-cycle and to prove efficiency of copywriting by its application on specific web site. Thesis' contribution, except from outlining important -- but still unappreciated -- web copywriter's role, is to integrate web copywriting into separate phases of web development life-cycle. Practical part of thesis is bene...

Rizal’s Legacy for the 21st Century: Progressive Education, Social Entrepreneurship and Community Development in Dapitan

Directory of Open Access Journals (Sweden)

Floro Quibuyen

2011-12-01

Full Text Available Rizal’s four years in Dapitan have not been fully explored for the light they can shed on contemporary issues in community development and education. In particular, the significance of the school he founded in Talisay has not merited scholarly commentary. Those fruitful four years in Dapitan have become Rizal’s most unappreciated legacy, yet they are precisely what make Rizal singularly relevant to the 21st century. This essay explains why.

Psychobiological mechanisms of exercise dependence.

Science.gov (United States)

Hamer, Mark; Karageorghis, Costas I

2007-01-01

Exercise dependence (ED) is characterised by an obsessive and unhealthy preoccupation with exercise. Previous research has focused largely on identifying behavioural aspects of ED, although the biological mechanisms remain unknown and are under researched. We review various ED hypotheses including affect regulation, anorexia analogue, sympathetic arousal and beta-endorphin. We also present a novel hypothesis pertaining to ED and interleukin (IL)-6, which combines previous hypotheses with literature from the field of psycho-neuroimmunology. We explore the notion that IL-6 provides a link from the periphery to the brain, which may mediate the underlying features of ED. We propose a conceptual model indicating that, in individuals prone to ED, exercise results in a transient reduction in negative affect, but concurrently results in excessive production of IL-6 and the activation of neuroendocrine pathways, which are associated with behavioural and psychological disturbances of exercise withdrawal. Our intention is for this model to serve as a basis for further research in the area of ED, which may eventually lead to the development of successful treatment strategies. Recent developments in methods to reliably assess these biological markers from blood and saliva samples should encourage such research to be undertaken in exercise settings.

Design of a Mechanical NaK Pump for Fission Space Power

Science.gov (United States)

Mireles, Omar R.; Bradley, David E.; Godfroy, Thomas

2011-01-01

Alkali liquid metal cooled fission reactor concepts are under development for spaceflight power requirements. One such concept utilizes a sodium-potassium eutectic (NaK) as the primary loop working fluid, which has specific pumping requirements. Traditionally, electromagnetic linear induction pumps have been used to provide the required flow and pressure head conditions for NaK systems but they can be limited in performance, efficiency, and number of available vendors. The objective of the project was to develop a mechanical NaK centrifugal pump that takes advantages of technology advances not available in previous liquid metal mechanical pump designs. This paper details the design, build, and performance test of a mechanical NaK pump developed at NASA Marshall Space Flight Center. The pump was designed to meet reactor cooling requirements using commercially available components modified for high temperature NaK service.

A rolling circle replication mechanism produces multimeric lariats of mitochondrial DNA in Caenorhabditis elegans.

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Samantha C Lewis

2015-02-01

Full Text Available Mitochondrial DNA (mtDNA encodes respiratory complex subunits essential to almost all eukaryotes; hence respiratory competence requires faithful duplication of this molecule. However, the mechanism(s of its synthesis remain hotly debated. Here we have developed Caenorhabditis elegans as a convenient animal model for the study of metazoan mtDNA synthesis. We demonstrate that C. elegans mtDNA replicates exclusively by a phage-like mechanism, in which multimeric molecules are synthesized from a circular template. In contrast to previous mammalian studies, we found that mtDNA synthesis in the C. elegans gonad produces branched-circular lariat structures with multimeric DNA tails; we were able to detect multimers up to four mtDNA genome unit lengths. Further, we did not detect elongation from a displacement-loop or analogue of 7S DNA, suggesting a clear difference from human mtDNA in regard to the site(s of replication initiation. We also identified cruciform mtDNA species that are sensitive to cleavage by the resolvase RusA; we suggest these four-way junctions may have a role in concatemer-to-monomer resolution. Overall these results indicate that mtDNA synthesis in C. elegans does not conform to any previously documented metazoan mtDNA replication mechanism, but instead are strongly suggestive of rolling circle replication, as employed by bacteriophages. As several components of the metazoan mitochondrial DNA replisome are likely phage-derived, these findings raise the possibility that the rolling circle mtDNA replication mechanism may be ancestral among metazoans.

Effects of mechanical feedback on the stability of cardiac scroll waves: A bidomain electro-mechanical simulation study.

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Colli Franzone, P; Pavarino, L F; Scacchi, S

2017-09-01

In this work, we investigate the influence of cardiac tissue deformation on re-entrant wave dynamics. We have developed a 3D strongly coupled electro-mechanical Bidomain model posed on an ideal monoventricular geometry, including fiber direction anisotropy and stretch-activated currents (SACs). The cardiac mechanical deformation influences the bioelectrical activity with two main mechanical feedback: (a) the geometric feedback (GEF) due to the presence of the deformation gradient in the diffusion coefficients and in a convective term depending on the deformation rate and (b) the mechano-electric feedback (MEF) due to SACs. Here, we investigate the relative contribution of these two factors with respect to scroll wave stability. We extend the previous works [Keldermann et al., Am. J. Physiol. Heart Circ. Physiol. 299, H134-H143 (2010) and Hu et al., PLoS One 8(4), e60287 (2013)] that were based on the Monodomain model and a simple non-selective linear SAC, while here we consider the full Bidomain model and both selective and non-selective components of SACs. Our simulation results show that the stability of cardiac scroll waves is influenced by MEF, which in case of low reversal potential of non-selective SACs might be responsible for the onset of ventricular fibrillation; GEF increases the scroll wave meandering but does not determine the scroll wave stability.

Transcriptomic responses to darkness stress point to common coral bleaching mechanisms

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Desalvo, M. K.; Estrada, A.; Sunagawa, S.; Medina, Mónica

2012-03-01

Coral bleaching occurs in response to numerous abiotic stressors, the ecologically most relevant of which is hyperthermic stress due to increasing seawater temperatures. Bleaching events can span large geographic areas and are currently a salient threat to coral reefs worldwide. Much effort has been focused on understanding the molecular and cellular events underlying bleaching, and these studies have mainly utilized heat and light stress regimes. In an effort to determine whether different stressors share common bleaching mechanisms, we used complementary DNA (cDNA) microarrays for the corals Acropora palmata and Montastraea faveolata (containing >10,000 features) to measure differential gene expression during darkness stress. Our results reveal a striking transcriptomic response to darkness in A. palmata involving chaperone and antioxidant up-regulation, growth arrest, and metabolic modifications. As these responses were previously measured during thermal stress, our results suggest that different stressors may share common bleaching mechanisms. Furthermore, our results point to hypoxia and endoplasmic reticulum stress as critical cellular events involved in molecular bleaching mechanisms. On the other hand, we identified a meager transcriptomic response to darkness in M. faveolata where gene expression differences between host colonies and sampling locations were greater than differences between control and stressed fragments. This and previous coral microarray studies reveal the immense range of transcriptomic responses that are possible when studying two coral species that differ greatly in their ecophysiology, thus pointing to the importance of comparative approaches in forecasting how corals will respond to future environmental change.

Recurrent severe invasive pneumococcal disease in an adult with previously unknown hyposplenia

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Ballegaard, Vibe C; Schejbel, Lone; Hoffmann, Steen

2015-01-01

was found. Despite immunization against S. pneumoniae and measurement of what was interpreted as protective levels of serotype-specific IgG antibodies after vaccination, the patient suffered from a third episode of IPD. CONCLUSIONS: Individuals with predisposing medical conditions or a history of severe......BACKGROUND: The risk of life-threatening and invasive infections with encapsulated bacteria is increased in patients with hyposplenia or asplenia. We report a case of recurrent invasive pneumococcal meningitis in a woman with previous unknown hyposplenia. She was vaccinated after the first episode...... of meningitis and developed sufficient levels of pneumococcal antibodies. The pneumococcal strains isolated were serotype 7 F and 17 F. To our knowledge, there has been no previously reported case of recurrent invasive pneumococcal disease in a pneumococcal vaccinated adult with hyposplenia and apparently...

Fast self-diffusion of ions in CH ₃ NH ₃ PbI ₃ : the interstiticaly mechanism versus vacancy-assisted mechanism

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Yang, Ji-Hui; Yin, Wan-Jian; Park, Ji-Sang; Wei, Su-Huai

2016-01-01

The stability of organic-inorganic halide perovskites is a major challenge for their applications and has been extensively studied. Among the possible underlying reasons, ion self-diffusion has been inferred to play important roles. While theoretical studies congruously support that iodine is more mobile, experimental studies only observe the direct diffusion of the MA ion and possible diffusion of iodine. The discrepancy may result from the incomplete understanding of ion diffusion mechanisms. With the help of first-principles calculations, we studied ion diffusion in CH3NH3PbI3 (MAPbI3) through not only the vacancy-assisted mechanisms presumed in previous theoretical studies, but also the neglected interstiticaly mechanisms. We found that compared to the diffusion through the vacancy-assisted mechanism, MA ion diffusion through the interstiticaly mechanism has a much smaller barrier which could explain experimental observations. For iodine diffusion, both mechanisms can yield relatively small barriers. Depending on the growth conditions, defect densities of vacancies and interstitials can vary and so do the diffusion species as well as diffusion mechanisms. Our work thus supports that both MA and iodine ion diffusion could contribute to the performance instability of MAPbI3. While being congruous with experimental results, our work fills the research gap by providing a full understanding of ion diffusion in halide perovskites.

Why do tougher caseworkers increase employment? The role of programme assignment as a causal mechanism

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Huber, Martin; Lechner, Michael; Mellace, Giovanni

Previous research found that less accommodating caseworkers are more successful in placing unemployed workers into employment. This paper tries to shed more light on the causal mechanisms behind this result using semiparametric mediation analysis. Analysing very informative linked jobseeker...

Atomistic detailed mechanism and weak cation-conducting activity of HIV-1 Vpu revealed by free energy calculations.

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Siladitya Padhi

Full Text Available The viral protein U (Vpu encoded by HIV-1 has been shown to assist in the detachment of virion particles from infected cells. Vpu forms cation-specific ion channels in host cells, and has been proposed as a potential drug target. An understanding of the mechanism of ion transport through Vpu is desirable, but remains limited because of the unavailability of an experimental structure of the channel. Using a structure of the pentameric form of Vpu--modeled and validated based on available experimental data--umbrella sampling molecular dynamics simulations (cumulative simulation time of more than 0.4 µs were employed to elucidate the energetics and the molecular mechanism of ion transport in Vpu. Free energy profiles corresponding to the permeation of Na+ and K+ were found to be similar to each other indicating lack of ion selection, consistent with previous experimental studies. The Ser23 residue is shown to enhance ion transport via two mechanisms: creating a weak binding site, and increasing the effective hydrophilic length of the channel, both of which have previously been hypothesized in experiments. A two-dimensional free energy landscape has been computed to model multiple ion permeation, based on which a mechanism for ion conduction is proposed. It is shown that only one ion can pass through the channel at a time. This, along with a stretch of hydrophobic residues in the transmembrane domain of Vpu, explains the slow kinetics of ion conduction. The results are consistent with previous conductance studies that showed Vpu to be a weakly conducting ion channel.