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Sample records for justin stiff senior

  1. Justine user`s manual

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.R.

    1995-10-01

    Justine is the graphical user interface to the Los Alamos Radiation Modeling Interactive Environment (LARAMIE). It provides LARAMIE customers with a powerful, robust, easy-to-use, WYSIWYG interface that facilitates geometry construction and problem specification. It is assumed that the reader is familiar with LARAMIE, and the transport codes available, i.e., MCNPTM and DANTSYSTM. No attempt is made in this manual to describe these codes in detail. Information about LARAMIE, DANTSYS, and MCNP are available elsewhere. It i also assumed that the reader is familiar with the Unix operating system and with Motif widgets and their look and feel. However, a brief description of Motif and how one interacts with it can be found in Appendix A.

  2. "Justine's story" and the art of nursing.

    Science.gov (United States)

    Baker, Paige

    2008-03-01

    The author of this response to Dr. Kathryn Gramling's research on the art of nursing as perceived by patients agrees with patient Justine's assessment of the art. The author believes that the expression of a nurse's personality during the caring process creates the art. Justine saw all her nurses, even the brusque one, as performing in a caring way, each according to his/her own personality. The author believes this definition of the art of nursing is valid.

  3. Kroonika esitleb : Justin Timberlake ja Rod Stewart / Justin Timberlake ; interv. Katrin Lust-Buchanan

    Index Scriptorium Estoniae

    Timberlake, Justin

    2006-01-01

    Meesteajakirja GQ auhindade jagamise tseremoonial Londonis sai ajakirja Kroonika reporter jutule aasta rahvusvahelisima mehe tiitli pälvinud Justin Timberlake'i ja elutööpreemia saanud Rod Stewartiga

  4. Kroonika esitleb : Justin Timberlake ja Rod Stewart / Justin Timberlake ; interv. Katrin Lust-Buchanan

    Index Scriptorium Estoniae

    Timberlake, Justin

    2006-01-01

    Meesteajakirja GQ auhindade jagamise tseremoonial Londonis sai ajakirja Kroonika reporter jutule aasta rahvusvahelisima mehe tiitli pälvinud Justin Timberlake'i ja elutööpreemia saanud Rod Stewartiga

  5. Justin Bieber - en toneangivende formidler til tweens

    OpenAIRE

    Lundeby, Maria Celine Kolberg

    2014-01-01

    Ønsket mitt med oppgaven har vært å skape en bevissthet om at populærkulturen er en formidler av noe, og at dette noe bærer i seg potensialet til å ha direkte betydning for vanlige menneskers liv. Gjennom dette utblikket har målet vært å synliggjøre noen eksempler på hvordan det som formidles kan bli gode innfallsvinkler til samtaler om og forkynnelse av kristen tro til tweens. Selv om denne oppgaven har tatt utgangspunkt i et veldig konkret eksempel, Justin Bieber, er de grunnleg...

  6. Justin Bieber欧美新偶像

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    来自加拿大年仅16岁的青少年偶像贾斯汀·比伯Justin Bleber凭借个人第二张专辑《我的世界2.0》(My World2.0)以绝对优势统治了美国专辑榜。更值得一提的是,这位年轻歌手发表这张专辑仅仅才一周。

  7. Meet EPA Researcher Justin Conley, Ph.D.

    Science.gov (United States)

    Justin Conley is a postdoctoral researcher investigating the toxicity of endocrine disrupting chemicals and new approaches for water quality monitoring. When he is not in the lab, he is busy brewing beer and exploring the outdoors.

  8. Sugar Free with Justin T.: Diabetes Education through Community Partnerships

    Science.gov (United States)

    Thomas, Justin B.; Donaldson, Joseph L.

    2014-01-01

    This article describes the design, development, and delivery of an Extension community cable television program, "Sugar Free with Justin T.," in Roane County, Tennessee. The program targets diabetics, pre-diabetics, and those who care for them, with practical information and demonstrations to improve dietary quality. In addition to…

  9. Sugar Free with Justin T.: Diabetes Education through Community Partnerships

    Science.gov (United States)

    Thomas, Justin B.; Donaldson, Joseph L.

    2014-01-01

    This article describes the design, development, and delivery of an Extension community cable television program, "Sugar Free with Justin T.," in Roane County, Tennessee. The program targets diabetics, pre-diabetics, and those who care for them, with practical information and demonstrations to improve dietary quality. In addition to…

  10. TWO VIEWS ON F. DOSTOEVSKY: OSCAR VON SCHOULTZ AND THE REVEREND JUSTIN (POPOVITCH

    Directory of Open Access Journals (Sweden)

    Velikoselskiy A. V.

    2011-11-01

    Full Text Available This article provides a comparative analysis of two studies by two researchers of Dostoevsky’s creative work — Finnish slavist Oscar von Schoultz and Serbian religious thinker The Reverend Justin Popović. It focuses primarily on the system and evolution of positive and negative characters of Dostoevsky's novels in the context of faith and unbelief.

  11. Abject Magic: Reasoning Madness in Justine Larbalestier's "Magic or Madness" Trilogy

    Science.gov (United States)

    Potter, Troy

    2013-01-01

    This paper explores the representation of magic and madness in Justine Larbalestier's "Magic or Madness" trilogy (2005-2007). Throughout the series, magic is constructed as an abject and disabling force that threatens to disable magic-wielders, either through madness or death. Despite being represented as a ubiquitous force, the…

  12. Senior cyclists.

    NARCIS (Netherlands)

    2015-01-01

    The use of the bicycle has increased these last few years, especially among seniors. The number of seniors annually sustaining serious injuries as a result of a cycling crash is substantial (4,280) and has been increasing these last few years. Moreover, circa 120 seniors (55+) die in a cycling crash

  13. Senior cyclists.

    NARCIS (Netherlands)

    2015-01-01

    The use of the bicycle has increased these last few years, especially among seniors. The number of seniors annually sustaining serious injuries as a result of a cycling crash is substantial (4,280) and has been increasing these last few years. Moreover, circa 120 seniors (55+) die in a cycling crash

  14. Justin Bieber, do doc ao Instagram: a estetização da vida

    Directory of Open Access Journals (Sweden)

    Denise Tavares

    2013-12-01

    Full Text Available Alguns documentários biográficos de celebridades reafirmam um modelo de produção audiovisual que encerra a história de vida no show e na fama, articulando o tensionamento entre biografia, tecnologia, experiência estética e afeto. Tais imbricamentos são ainda mais visíveis quando considerada a fruição desta celebridade, “consumida” em outras possibilidades biográficas que remixa webvideos postados no Youtube e/ou fotos no Instagram. Para discutir estas questões, o artigo destaca Justin Bieber, tendo como ponto de partida o documentário Justin Bieber – Never Say Never (2011, de Jon M. Chu e o Instagram, em um recorte que privilegia a experiência dos desejos dos fãs.

  15. Justin Bieber 为新单曲拍MV现场跳贴身热舞

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    当地时间2012年4月21日,小天王贾斯汀一比伯(Justin Bieber)在美国洛杉矶为新曲《男朋友》拍摄MV,当天拍摄的是与女主角的亲密戏码,小天王频频笑场NG。

  16. Justin Bieber, do doc ao Instagram: a estetização da vida

    OpenAIRE

    Denise Tavares; Raphael Pinto

    2013-01-01

    Alguns documentários biográficos de celebridades reafirmam um modelo de produção audiovisual que encerra a história de vida no show e na fama, articulando o tensionamento entre biografia, tecnologia, experiência estética e afeto. Tais imbricamentos são ainda mais visíveis quando considerada a fruição desta celebridade, “consumida” em outras possibilidades biográficas que remixa webvideos postados no Youtube e/ou fotos no Instagram. Para discutir estas questões, o artigo destaca Justin Bieber,...

  17. Justin Bieber

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    贾斯汀·比伯是人气正在迅速上升的加.拿大少年歌手。他的个人单曲《OneTime》一经推出便风靡全球,第二首单曲《OneLessLonelyGirl》首周上榜便取得了榜单第16位的好成绩。尤其是(Baby))这首歌曲在You.Tube上的点击量超过四亿。那么年纪轻轻的贾斯汀·比伯是怎么走上音乐之路的呢?

  18. Stiff railguns

    Science.gov (United States)

    Weldon, W. F.; Bacon, J. L.; Weeks, D. A.; Zowarka, R. C., Jr.

    1991-01-01

    Stiff guns have been operated with both plasma and solid armatures. A performance gain was seen in the plasma railgun as stiffness was increased. A stiff gun will help to maintain the bore shape and preserve the integrity of the seam between rail and insulator under the extreme asymmetric loads sustained during high-pressure operation. The hydraulically preloaded moly and ceramic gun has been fired six times at pressures as high as 87 ksi, and the bore still holds roughing vacuum up to two hours after the test. The elimination of seam leakage helps control bore erosion associated with plasma reconstitution from the rail and plasma perturbation that might result in loss-initiating instabilities. Reduced rail deflection allows solid and transitioning armatures to track the bore surface. An analysis of the strain energy associated with the deflection of the railgun structure is presented, and this mechanism is found to be a small fraction of the energy associated with armature loss and the rail resistive loss.

  19. The Victorian Philanthropic Quixote: Donna Quixote, by Justin McCarthy

    Directory of Open Access Journals (Sweden)

    Pedro Javier Pardo

    2012-12-01

    Full Text Available The paper undertakes the analysis of a little known Victorian quixotic novel, Donna Quixote, by Justin McCarthy. In so doing, it places the latter, in the first place, within the conception of quixotism characteristic of the Victorian age and, in the second place, within the previous tradition of female quixotes, particularly as a response to George Eliot’s Middlemarch. Then, the text studies the novel’s originality within the English quixotic tradition, which lies in the way it relates quixotism to both philanthropy and feminism, not just by means of the heroine but also of some quixotic secondary figures, and argues the author’s conservative position in the debate on women’s rights known as the woman question. Finally, the paper illustrates such a position and its ideological context by presenting another “Donna Quixote,” in this case a satiric cartoon on the so-called new woman.

  20. Arterial Stiffness.

    Science.gov (United States)

    Avolio, Alberto

    2013-04-01

    Stiffness of large arteries has been long recognized as a significant determinant of pulse pressure. However, it is only in recent decades, with the accumulation of longitudinal data from large and varied epidemiological studies of morbidity and mortality associated with cardiovascular disease, that it has emerged as an independent predictor of cardiovascular risk. This has generated substantial interest in investigations related to intrinsic causative and associated factors responsible for the alteration of mechanical properties of the arterial wall, with the aim to uncover specific pathways that could be interrogated to prevent or reverse arterial stiffening. Much has been written on the haemodynamic relevance of arterial stiffness in terms of the quantification of pulsatile relationships of blood pressure and flow in conduit arteries. Indeed, much of this early work regarded blood vessels as passive elastic conduits, with the endothelial layer considered as an inactive lining of the lumen and as an interface to flowing blood. However, recent advances in molecular biology and increased technological sophistication for the detection of low concentrations of biochemical compounds have elucidated the highly important regulatory role of the endothelial cell affecting vascular function. These techniques have enabled research into the interaction of the underlying passive mechanical properties of the arterial wall with the active cellular and molecular processes that regulate the local environment of the load-bearing components. This review addresses these emerging concepts.

  1. Sexede seniorer

    DEFF Research Database (Denmark)

    Oxlund, Bjarke

    2010-01-01

    Aldring og seksualitet er begreber, der sjældent optræder i samme sætning. Det skyldes, at ældre menneskers seksuelle aktivitet længe har et tabuiseret felt. Nyere forskning dokumenterer imidlertid, at der er god grund til at se nærmere på de sexede seniorer, for ældre mennesker giver i stigende ...

  2. The first federal budget under Prime Minister Justin Trudeau: Addressing social determinants of health?

    Science.gov (United States)

    Ruckert, Arne; Labonté, Ronald

    2016-08-15

    A challenging budget environment during the Harper years has meant that crucial investments in the social determinants of health (SDHs) have increasingly been neglected. The tabling of what is widely considered a more progressive budget with expansionary fiscal elements under the new Prime Minister, Justin Trudeau, raises the question as to what extent this budget invests in policy areas that are crucial for achieving a more equitable distribution in the social determinants of health, as promised in the Liberal party platform. In this commentary, we argue that the first Liberal budget represents a step in the right direction, but that this first step needs to be followed up with a sustained commitment to address the pervasive (and unfair) social inequalities that are the root cause of persistent health inequities in Canada. We conclude that the first Trudeau budget, while moving in the right direction, does not fully embody the sustained policy changes needed to effectively address SDHs, including a more expansive role for the federal government in the redistribution of income and wealth.

  3. "Bieber Fever". Um aðdáun unglingsstúlkna á Justin Bieber

    OpenAIRE

    Sigurlín Sumarliðadóttir 1989

    2013-01-01

    Í þessari ritgerð ætla ég að skoða hvort aðdáun unglingsstúlkna á poppstirninu Justin Bieber geti flokkast sem átrúnaður. Meginspurning ritgerðarinnar er: Getur aðdáun þessara stúlkna flokkast sem trú? Markmið ritgerðarinnar er að varpa ljósi á aðdáun þessarra stúlkna og og hvernig hún geti flokkast sem trú. Trú er stórt og áhugavert fyrirbæri sem hefur marga fleti. Trú er mis mikilvæg fyrir fólk og fyrir suma hefur hún ekkert vægi. Trú er svo margslungin að kannski má segja að...

  4. Man – body and soul, as well as the relationship between them in the view of St. Justin the Martyr and Philosopher

    Directory of Open Access Journals (Sweden)

    ROTARU Ioan-Gheorghe

    2014-11-01

    Full Text Available Among the first Church Fathers, where we find the concern for anthropological issues, is St. Justin the Martyr and the Philosopher. Even though St. Justin has not developed a proper anthropology, because it was too early for such a performance, however he draw a few lines in this regard, that influenced later patristic tradition, also showing interest in humanist culture in general, because this culture has a pronounced character of continuity, keeping the principles of permanent value, principles earned through the efforts of the spirit and society over time. Man, in the conception of St. Justin the Martyr and the Philosopher, is a rational being comprised of two elements: body and soul. Taken separately, the two elements, body or soul, do not form the man, this being the union and unity of the two elements. Sf. Justin says that God, summoned to life and resurrection this entire assembly, that is the man, and not just a part of him. He considers man as being a miracle, if we take into account the small drop of seed which he derives from and which produces and develops the bones, nerves and flesh. As for the relationship between body and soul, St. Justin the Martyr and the Philosopher says that they are closely connected by the very act of creation.

  5. 风险投资家:Justin Bieber乐坛巨星贾斯汀·比伯

    Institute of Scientific and Technical Information of China (English)

    徐宝成

    2012-01-01

    他有着招牌式的金色头发和孩子般无邪的笑,他英俊,极具天赋,极为富有,而且每一分钱都是自己赚来的,从事自己喜欢的工作还吸引了无数人。这个人就是乐坛巨星——贾斯汀·比伯(Justin Bieber)。

  6. Stiffness in the Hand

    Science.gov (United States)

    ... include: Arthritis Fractures Dislocations Bad sprains Tendon and muscle injuries Evaluating Hand Stiffness Your doctor will ask when the stiffness ... scan. CAUSES SIGNS AND ... stretching exercises for the joints and muscles to help loosen them. Different types of splints ...

  7. Stiff person syndrome.

    Science.gov (United States)

    Ciccoto, Giuseppe; Blaya, Maike; Kelley, Roger E

    2013-02-01

    Recognizing stiff person syndrome is clinically important. It is uncommon, characterized by body stiffness associated with painful muscle spasms, and varies in location and severity. It is subdivided into stiff trunk versus stiff limb presentation, and as a progressive encephalomyelitis. Stiff person-type syndrome also reflects a paraneoplastic picture. Most patients demonstrate exaggerated lumbar lordosis. Roughly 60% of patients have antiglutamic acid decarboxylase antibodies in the blood and the cerebrospinal fluid. The differential diagnosis includes many severe conditions. There are reports of response to muscle relaxants, immunosuppressants, intravenous gamma globulin, plasma exchange, a number of anticonvulsants, and botulinum toxin.

  8. Seniors and Anesthesia

    Science.gov (United States)

    ... Anesthesia Seniors and Anesthesia Surgery Risks Anesthesia Awareness Obesity and Anesthesia Sleep Apnea and Anesthesia Smoking and Anesthesia Outpatient Surgery Seniors and Anesthesia The older you are, the more ...

  9. 泰勒与贾斯汀为赛琳娜争风吃醋!%Talyor and Justin Fight over Selena!

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    I was so excited when my BFF Selena Gomez came home to Texas for the weekend. But I was so shocked when she surprised me by bringing her friends Taylor Lautner and Justin Bieber with her. I gave them a shy smile as Selena pulled me upstairs.

  10. 给比伯的弟妹当保姆%I Babysit for Justin Bieber's Sibings!

    Institute of Scientific and Technical Information of China (English)

    Fireheartz

    2012-01-01

    Brring! I snapped out of my Justin Bieber wedding daydream as the final bell rang in seventh period. Back to the reality of being just another random^3 JB fan. But I had bigger things to worry about--like how I was going to get enough money to buythe perfect dress for the eighth-grade dance.%贾斯汀·比伯是人气正旺的加拿大少年歌手。他不仅在音乐上有惊人的才华:创作、打鼓、跳舞、弹吉他、弹琴、小号样样行,而且长相很萌很帅气。他现在居住在美国并在美国发展。他的粉丝遍布世界各地。

  11. Estimating Gear Teeth Stiffness

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2013-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...... and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffness’s of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact length is constant....

  12. Stiffness of compression devices

    Directory of Open Access Journals (Sweden)

    Giovanni Mosti

    2013-03-01

    Full Text Available This issue of Veins and Lymphatics collects papers coming from the International Compression Club (ICC Meeting on Stiffness of Compression Devices, which took place in Vienna on May 2012. Several studies have demonstrated that the stiffness of compression products plays a major role for their hemodynamic efficacy. According to the European Committee for Standardization (CEN, stiffness is defined as the pressure increase produced by medical compression hosiery (MCH per 1 cm of increase in leg circumference.1 In other words stiffness could be defined as the ability of the bandage/stockings to oppose the muscle expansion during contraction.

  13. Justine o la crítica política, ética y psicosocial de la sádica actualidad

    OpenAIRE

    Jorge Veraza Urtuzuástegui

    2011-01-01

    La obra del marqués de Sade es una crítica de la modernidad en sus diversos aspectos: economía, política y cultura, con énfasis en la crítica jurídica, ética y psicosocial que tiene como clave la conducta sexual y emocional. Todo esto destaca en su célebre novela Justine o los infortunios de la virtud. Este artículo busca contrarrestar las falsas interpretaciones que se han hecho de Justine y de la obra de Sade en general, que han terminado por desleer la valiosísima crítica que hace de la mo...

  14. Posttraumatic stiff elbow

    Directory of Open Access Journals (Sweden)

    Ravi Mittal

    2017-01-01

    Full Text Available Posttraumatic stiff elbow is a frequent and disabling complication and poses serious challenges for its management. In this review forty studies were included to know about the magnitude of the problem, causes, pathology, prevention, and treatment of posttraumatic stiff elbow. These studies show that simple measures such as internal fixation, immobilization in extension, and early motion of elbow joint are the most important steps that can prevent elbow stiffness. It also supports conservative treatment in selected cases. There are no clear guidelines about the choice between the numerous procedures described in literature. However, this review article disproves two major beliefs-heterotopic ossification is a bad prognostic feature, and passive mobilization of elbow causes elbow stiffness.

  15. Posttraumatic stiff elbow

    Science.gov (United States)

    Mittal, Ravi

    2017-01-01

    Posttraumatic stiff elbow is a frequent and disabling complication and poses serious challenges for its management. In this review forty studies were included to know about the magnitude of the problem, causes, pathology, prevention, and treatment of posttraumatic stiff elbow. These studies show that simple measures such as internal fixation, immobilization in extension, and early motion of elbow joint are the most important steps that can prevent elbow stiffness. It also supports conservative treatment in selected cases. There are no clear guidelines about the choice between the numerous procedures described in literature. However, this review article disproves two major beliefs-heterotopic ossification is a bad prognostic feature, and passive mobilization of elbow causes elbow stiffness.

  16. Food Safety for Seniors

    Science.gov (United States)

    ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Food Home Food Foodborne Illness & Contaminants People at Risk of Foodborne Illness To Your Health! Food Safety for Seniors Share Tweet Linkedin Pin it ...

  17. Housing Options for Seniors

    Science.gov (United States)

    ... different services. The services are based on the lifestyle and health care needs of the residents. Below are some options for senior living. Active adult communitiesActive adult communities are neighborhoods made for older ...

  18. Leg stiffness primarily depends on ankle stiffness during human hopping.

    Science.gov (United States)

    Farley, C T; Morgenroth, D C

    1999-03-01

    When humans hop in place or run forward, they adjust leg stiffness to accommodate changes in stride frequency or surface stiffness. The goal of the present study was to determine the mechanisms by which humans adjust leg stiffness during hopping in place. Five subjects hopped in place at 2.2 Hz while we collected force platform and kinematic data. Each subject completed trials in which they hopped to whatever height they chose ("preferred height hopping") and trials in which they hopped as high as possible ("maximum height hopping"). Leg stiffness was approximately twice as great for maximum height hopping as for preferred height hopping. Ankle torsional stiffness was 1.9-times greater while knee torsional stiffness was 1.7-times greater in maximum height hopping than in preferred height hopping. We used a computer simulation to examine the sensitivity of leg stiffness to the observed changes in ankle and knee stiffness. Our model consisted of four segments (foot, shank, thigh, head-arms-trunk) interconnected by three torsional springs (ankle, knee, hip). In the model, increasing ankle stiffness by 1.9-fold, as observed in the subjects, caused leg stiffness to increase by 2.0-fold. Increasing knee stiffness by 1.7-fold had virtually no effect on leg stiffness. Thus, we conclude that the primary mechanism for leg stiffness adjustment is the adjustment of ankle stiffness.

  19. Senior Power at North Hennepin

    Science.gov (United States)

    Sugnet, Charles J.

    1976-01-01

    Since 1970 North Hennepin Community College in Minneapolis has enrolled 3,411 in its Seniors on Campus program for senior citizens. The key to initiation and continuing development of the program described here is involvement of senior citizens themselves in the Senior Advisory Committee. (JT)

  20. Nomenclatural Studies Toward a World List of Diptera Genus-Group Names. Part V: Pierre-Justin-Marie Macquart.

    Science.gov (United States)

    Evenhuis, Neal L; Pape, Thomas; Pont, Adrian C

    2016-09-30

    The Diptera genus-group names of Pierre-Justin-Marie Macquart are reviewed and annotated. A total of 399 available genus-group names in 69 families of Diptera are listed alphabetically, for each name giving author, year and page of original publication, originally included species, type species and method of fixation, current status of the name, family placement, and a list of any emendations of it that have been found in the literature. Remarks are given to clarify nomenclatural or taxonomic information. In addition, an index to all the species-group names of Diptera proposed by Macquart (3,611, of which 3,543 are available) is given with bibliographic reference (year and page) to each original citation.        The following type species are designated herein: Agculocera nigra Macquart, 1855 for Onuxicera Macquart, 1855, present designation [Tachinidae]; Trixa imhoffi Macquart, 1834, for Semiomyia Macquart, 1848, present designation [Tachinidae].        The following type species are designated herein with fixation under ICZN Code Art. 70.3.2: Azelia nebulosa Robineau-Desvoidy, 1830 for Atomogaster Macquart, 1835, present designation [Muscidae]; Tachydromia vocatoria Fallén, 1816 for Chelipoda Macquart, 1835, present designation [Empididae]; Eriocera macquarti Enderlein, 1912 for Eriocera Macquart, 1838, present designation [Limoniidae]; Limosina acutangula Zetterstedt, 1847 for Heteroptera Macquart, 1835, present designation [Sphaeroceridae]; Phryxe pavoniae Robineau-Desvoidy, 1830 for Masicera Macquart, 1834, present designation [Tachinidae]; Pachymyia macquartii Townsend, 1916 for Pachymyia Macquart, 1844, present designation [Tachinidae].        Earlier valid subsequent type-species designations have been found in this study for the following: Anisophysa Macquart, 1835 [Sepsidae]; Diphysa Macquart, 1838 [Stratiomyidae]; Pachyrhina Macquart, 1834 [Tipulidae]; Silbomyia Macquart, 1844 [Calliphoridae].        One name is raised from

  1. Dynamic stiffness of suction caissons

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten; Andersen, Lars

    The purpose of this report is to evaluate the dynamic soil-structure interaction of suction caissons for offshore wind turbines. The investigation is limited to a determination of the vertical dynamic stiffness of suction caissons. The soil surrounding the foundation is homogenous with linear...... of the skirt length, Poisson's ratio and the ratio between soil stiffness and skirt stiffness. Finally the dynamic behaviour at high frequencies is investigated....... viscoelastic properties. The dynamic stiffness of the suction caisson is expressed by dimensionless frequency-dependent dynamic stiffness coefficients corresponding to the vertical degree of freedom. The dynamic stiffness coefficients for the foundations are evaluated by means of a dynamic three...

  2. Stiff Quantum Polymers

    OpenAIRE

    Kleinert, H

    2007-01-01

    At ultralow temperatures, polymers exhibit quantum behavior, which is calculated here for the second and fourth moments of the end-to-end distribution in the large-stiffness regime. The result should be measurable for polymers in wide optical traps.

  3. Depression, Anxiety, and Arterial Stiffness

    NARCIS (Netherlands)

    Seldenrijk, Adrie; van Hout, Hein P. J.; van Marwijk, Harm W. J.; de Groot, Eric; Gort, Johan; Rustemeijer, Cees; Diamant, Michaela; Penninx, Brenda W. J. H.

    2011-01-01

    Background: Arterial stiffness gains attention as a potential mechanism underlying the frequently found association between depression or anxiety and cardiovascular disease. However, observations regarding stiffness and psychopathology were often based on small samples. The current study aimed to

  4. Genetics of Stiff Child Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-11-01

    Full Text Available A Chinese boy with a DYT1 gene mutation presented with muscle stiffness, painful muscle spasms, myoclonus, and dystonia, compatible with stiff child syndrome, and is reported from Queen Mary Hospital, the University of Hong Kong.

  5. Senior radio listeners

    DEFF Research Database (Denmark)

    Blaakilde, Anne Leonora

    Radiobroadcasting and the hardware materialization of radio have during the 20th century changed significantly, which means that senior radio listeners have travelled along with this evolution from large, impressive radio furnitures to DAB and small, wireless, mobile devices, and from grave...... and solemn radio voices to lightharted, laughing and chatting speakers. Senior radio listerners have experienced the development and refinements of technique, content and genres. It is now expected of all media users that they are capable of crossing media, combining, juggling and jumping between various...... media platforms, not the least when listening to radio. The elder generation is no exception from this. Recently, for instance, the Danish public broadcast DR has carried out an exodus of programmes targeted for the senior segment. These programmes are removed from regular FM and sent to DAB receivers...

  6. Simply computing for seniors

    CERN Document Server

    Clark, Linda

    2011-01-01

    Step-by-step instructions for seniors to get up and running on a home PC Answering the call for an up-to-date, straightforward computer guide targeted specifically for seniors, this helpful book includes easy-to-follow tutorials that escort you through the basics and shows you how to get the most out of your PC. Boasting an elegant, full-color interior with a clean, sophisticated look and feel, the layout makes it easy for you to find the information you need quickly. Author Linda Clark has earned her highly respected reputation through years of teaching computers at both the beginnin

  7. Senior Leader Career Management: Implications for Senior Leaders and Organizations

    Science.gov (United States)

    Larkin, Jean

    2012-01-01

    This qualitative research study across three large consumer products organizations explored career management of senior leaders to gain an understanding of what is important to senior leaders in their careers and what strategies they are using for career management. It also investigated senior leaders' expectations of organizations for career…

  8. Seniors' Lungs Can Tackle Exercise

    Science.gov (United States)

    ... news/fullstory_167082.html Seniors' Lungs Can Tackle Exercise Researchers find older adults' respiratory systems keep up ... News) If seniors want to start a vigorous exercise program, there's a good chance their lungs can ...

  9. On gear tooth stiffness evaluation

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Jørgensen, Martin Felix

    2014-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...... and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact width is constant. © 2014...

  10. Brain Training for Seniors

    Science.gov (United States)

    ... Article >>SeniorsDepression and Alzheimer’s DiseaseLearn about the causes, symptoms and treatment of depression in older adults who have Alzheimer’s disease.April 2014September 2000familydoctor.org editorial staffHealthy Habits ...

  11. Stiffness, resilience, compressibility

    Energy Technology Data Exchange (ETDEWEB)

    Leu, Bogdan M. [Argonne National Laboratory, Advanced Photon Source (United States); Sage, J. Timothy, E-mail: jtsage@neu.edu [Northeastern University, Department of Physics and Center for Interdisciplinary Research on Complex Systems (United States)

    2016-12-15

    The flexibility of a protein is an important component of its functionality. We use nuclear resonance vibrational spectroscopy (NRVS) to quantify the flexibility of the heme iron environment in the electron-carrying protein cytochrome c by measuring the stiffness and the resilience. These quantities are sensitive to structural differences between the active sites of different proteins, as illustrated by a comparative analysis with myoglobin. The elasticity of the entire protein, on the other hand, can be probed quantitatively from NRVS and high energy-resolution inelastic X-ray scattering (IXS) measurements, an approach that we used to extract the bulk modulus of cytochrome c.

  12. Pharmacological modulation of arterial stiffness.

    LENUS (Irish Health Repository)

    Boutouyrie, Pierre

    2011-09-10

    Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for \\'de-stiffening drugs\\

  13. Memory training with senior citizens

    OpenAIRE

    CHOVANCOVÁ, Lenka

    2014-01-01

    This is a theoretical work. It deals with the topics of senior citizens and the aging process in an abbreviated conception, periodization of old age, and active life of seniors. It describes forms of social work with seniors in medical facilities, home environments and communities, and in old people's homes. Further, it describes memory: its definition, types of memory, memory loss, reasons why people forget, work with memory and advice on memory improvement from the medical point of view. Th...

  14. Psychomotor activities with seniors

    Directory of Open Access Journals (Sweden)

    Jitka Kopřivová

    2015-07-01

    Full Text Available BACKGROUND: Given that the population all over the world is aging, it is necessary to fi nd ways to help maintain or improve the quality of life of seniors. The main goal of this paper is to show how appropriate physical activity programs contribute to the improvement of the functionality and psychosocial wellbeing of seniors. We are particularly interested in the possibilities of preserving self-suffi ciency and self-service, independence and the ability to perform everyday activities. One of the most eff ective forms of physical activity is psychomotr activity.OBJECTIVE: The aim of our paper is to present basic information concerning the meaning and the application of the psychomotr activities in intervention movement programmes in order to improve seniors’ life quality.METHODS: We defi ne the term psychomotr activities according to Adamírová (1995 and Novotná (2010. In this paper we present some results of research that stress the positive eff ect of psychomotor exercises and games on the life satisfaction of the elderly (Stará 2011; Stará & Kopřivová, 2011.DESCRIPTION: According to the results of our research and practical experience gained from working with the elderly it is strongly recommended to include suitable psychomotor exercises and games focusing on the development of manual dexterity in training programs in order to improve the balance abilities and the psychosocial area. In terms of prevention, because of the growing number of neurological disorders at an old age it is appropriate to include psychomotor exercises that encourage the development of cognitive functions in the physical interventions.CONCLUSION: We were able to positively infl uence the emotional aspect from performing physical activities, to enhance self-esteem of the exercising subjects and to create new social relationships. Motion programs, which also included psychomotor exercises and games, had a positive eff ect on the physical assessment of the

  15. Medication use among Canadian seniors.

    Science.gov (United States)

    McPherson, Mark; Ji, Hong; Hunt, Jordan; Ranger, Rob; Gula, Cheryl

    2012-01-01

    As they age, many seniors develop a progressively more complex mix of health conditions. Multiple prescription medications are often required to help manage these conditions and control symptoms, with the goal of maintaining seniors' health for as long as possible. This article explores trends in the number and types of medications used by seniors on public drug programs in Canada. Our findings suggest that a high proportion of Canadian seniors are taking several medications, highlighting the need for medication management systems focusing on this population.

  16. SENIOR THEATRE AN IMPORTANT PART OF SENIOR CULTURE

    Directory of Open Access Journals (Sweden)

    Rosemarie Kurz

    2016-06-01

    Full Text Available The third age is an opportunity and can be used wisely. Going to university, travelling, volunteering or joining a theater group could be possibilities. The article deals with Cultural Implications, and with senior theatre forging ahead in unexpected and adventurous directions. Last not least about the situation of Senior Theatre in Graz, Austria

  17. SENIOR THEATRE AN IMPORTANT PART OF SENIOR CULTURE

    OpenAIRE

    2016-01-01

    The third age is an opportunity and can be used wisely. Going to university, travelling, volunteering or joining a theater group could be possibilities. The article deals with Cultural Implications, and with senior theatre forging ahead in unexpected and adventurous directions. Last not least about the situation of Senior Theatre in Graz, Austria

  18. A Reply to Stiff and Boster.

    Science.gov (United States)

    Petty, Richard E.; And Others

    1987-01-01

    Addresses the major errors and misconceptions perpetuated by Stiff and Boster's response to criticism of Stiff's 1986 article. Focuses on the major conceptual and methodological issues of Stiff's model. (NKA)

  19. Stiffness of desiccating insect wings

    Energy Technology Data Exchange (ETDEWEB)

    Mengesha, T E; Vallance, R R [Department of Mechanical Engineering, The George Washington University, 738 Phillips Hall, 801 22nd St NW, Washington, DC 20052 (United States); Mittal, R, E-mail: vallance@gwu.edu [Department of Mechanical Engineering, Johns Hopkins University, 126 Latrobe Hall, 3400 N Charles Street, Baltimore, MD 21218 (United States)

    2011-03-15

    The stiffness of insect wings is typically determined through experimental measurements. Such experiments are performed on wings removed from insects. However, the wings are subject to desiccation which typically leads to an increase in their stiffness. Although this effect of desiccation is well known, a comprehensive study of the rate of change in stiffness of desiccating insect wings would be a significant aid in planning experiments as well as interpreting data from such experiments. This communication presents a comprehensive experimental analysis of the change in mass and stiffness of gradually desiccating forewings of Painted Lady butterflies (Vanessa cardui). Mass and stiffness of the forewings of five butterflies were simultaneously measured every 10 min over a 24 h period. The averaged results show that wing mass declined exponentially by 21.1% over this time period with a time constant of 9.8 h, while wing stiffness increased linearly by 46.2% at a rate of 23.4 {mu}N mm{sup -1} h{sup -1}. For the forewings of a single butterfly, the experiment was performed over a period of 1 week, and the results show that wing mass declined exponentially by 52.2% with a time constant of 30.2 h until it reached a steady-state level of 2.00 mg, while wing stiffness increased exponentially by 90.7% until it reached a steady-state level of 1.70 mN mm{sup -1}. (communication)

  20. Analytical theory for shape stiffness

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m=k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc=m+q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano's theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.

  1. Analytical theory for shape stiffness

    Institute of Scientific and Technical Information of China (English)

    张进之

    2000-01-01

    The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m = k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc = m + q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano’s theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.

  2. Senior Managers’ Network Tie Use

    DEFF Research Database (Denmark)

    Zarzecka, Olga; Villeseche, Florence

    While the importance or even necessity to build and maintain resourceful social networks appears as a forthright fact, there is still a lack of certainty as to who benefits from the resources that can be accessed through senior managers’ networks, and under what conditions. In this paper, we...... contribute to answering this puzzle with a sample constituted of senior managers from Denmark and their network ties, and investigate both economic and sociological conditions of senior managers’ tie use. Our results show that the greater the distance between aspiration level and actual firm performance......, the more likely it is that senior managers will use their network ties to access resources that benefit chiefly the individual rather than the organization. In addition, we demonstrate that this rapport is moderated by senior managers’ social identity as a member of the corporate elite, so that a strong...

  3. Senior Loken Syndrome

    Directory of Open Access Journals (Sweden)

    F Najafi

    2011-02-01

    Full Text Available The etiology of ESRD under the age of 20 almost is the inherited kidney disease or congenital disorders of urinary tract. NPHP/ medullary cystic disease includes a group of tubulo- genetic kidney disorders. NPHP is the cause of 15-20% ESRD in children and adolescents. The extra renal manifestations include: oculomotor Apraxia(Cogan syndrome, mental retardation, retinitis pigmentosa, (Senior- Loken syndrome liver fibrosis and skeletal disorders. Recently, on the basis of genetics and type of the protein product of these mutations, NPHP is divided to 6 types. The presented case is a 17 year old boy with end stage renal disease that he has been managed with hemodialysis. As the patient has polyuria and disturbance in vision from childhood and on physical examination he had retinitis pigmentosa and horizontal nystagmus with a history of chronic kidney disease in his 12 years old sister, and familial marriage between his parents, we suggest NPHP4 for the patient.

  4. Level Classifications of Foundation Stiffness

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten

    2007-01-01

    This article describes a foundation module developed and implemented in both HAWC and FLEX capable of to simulate the frequency dependent stiffness and damping of foundations e.g. pile, gravitation and bucket foundations.......This article describes a foundation module developed and implemented in both HAWC and FLEX capable of to simulate the frequency dependent stiffness and damping of foundations e.g. pile, gravitation and bucket foundations....

  5. Seafood: Nutritional Gold for Seniors

    Directory of Open Access Journals (Sweden)

    Alexandra McManus

    2010-12-01

    Full Text Available ObjectivesTo conduct a systematic review of published evidence around seafood, health and seniors.MethodData sources reviewing included: Proquest; PubMed; Science Direct; Taylor and Francis; Cochran Collaboration; Web of Knowledge and Web of Science. Key search terms included seniors, ageing, fish, seafood, protein, health and various lifestyle conditions Results A diet high in marine source Omega-3 poly unsaturated fatty acids affords particular benefits for seniors in a reduced risk of all cause mortality, with the strongest evidence around coronary heart disease and ischemic stroke. Other benefits include reduced inflammation associated with arthritis and delay to onset and slowed progression of dementia and Alzheimer’s disease. Conclusion There is increasing evidence to support the regular seafood consumption (particularly oily fish as being protective against a number of aged-related health conditions. Seniors should be encouraged to consume 3500mg- 4000mg of marine source Omega-3 PUFAs each week.

  6. Returns to Tenure or Seniority?

    DEFF Research Database (Denmark)

    Buhai, Ioan Sebastian; Portela, Miguel; Teulings, Coen

    at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers' .bargaining power to be in line with their share in the cost of specific investment. Then, the LIFO rule is a way...... to protect their property right on the specific investment. We consider the effects of Employment Protection Legislation and risk aversion....

  7. SENIOR STAFF ADVANCEMENT COMMITTEE (SSAC)

    CERN Document Server

    2000-01-01

    Composition and mandateThe Senior Staff Advancement Committee is composed of members nominated ad persona by the Director-General.The Committee examines proposals from Divisions concerning promotions to grade 13 in Career Path IX, changes of career path to Career Path IX and advancements to the exceptional grade in Career path VIII.The Director-General may consult the Committee on any matter related to senior staff careers.The Committee makes its recommendations to the Director-General.

  8. Foreign language education of seniors

    Directory of Open Access Journals (Sweden)

    Határ Ctibor

    2016-01-01

    Full Text Available This study is of a theoretical-conceptual nature and is a partial outcome of the research project VEGA MŠVVaŠ SR and SAV no. 1/0176/15. It deals with one of the problems currently faced by educational theory and practice, i.e. the foreign language education of seniors. The trend is typical for many EU member states, since it results from the needs of a modern society. In addition to strategic documents, programs and legislation which binds the Slovak Republic to create conditions for lifelong education, including foreign language education, the authors are more closely preoccupied with specificities and possibilities of the language education of seniors, which are explained on a comparative basis with the language education of children and youth. Even though in literature one can find results of many substantial empirical research projects devoted to foreign language education of children and youth, research into the education of adults and seniors in the area of foreign languages falls behind considerably. A sufficient platform for the methodology of language education of adults and seniors in Slovakia has not been created either, if compared with the methodology of language education of younger age categories. This shortcoming is often quite noticeable in practice. The study attempts to pay adequate attention to the analysis of selected teaching styles specific for adult and senior age as well as teaching methods which may be used in the language education of seniors.

  9. Analisis Kebutuhan Bandwidth Pada Pemanfaatan Web Streaming Justin.tv Sebagai Media E-Learning Dengan Menggunakan Wirecast Dan Desktop Presenter

    Directory of Open Access Journals (Sweden)

    Muhammad Ubaidilah

    2014-05-01

    Full Text Available Perkembangan teknologi informasi begitu cepat seperti sekarang telah banyak mengubah sudut pandang banyak orang, antara lain sudut pandang orang untuk mengubah dunia pendidikan menjadi lebih baik. Salah satu contohnya pembelajaran berbasis Information and Communication Technologies (ICT yaitu pembelajaran menggunakan video streaming. Dengan instalasi software open source Wirecast dan Desktop presenter digunakan untuk membuat video pembelajaran Streaming, disiarkan secara real time melalui media broadcast justin.tv (internet TV Channel, diharapkan dapat lebih mendukung konsep pembelajaran kapan dan dimana saja. Masalah terbesar dari teknologi ini adalah keterbatasan bandwidth. Bandwidth adalah parameter penting untuk melakukan streaming dalam jaringan. Sedangkan proses komunikasi menggunakan video digital ini menghabiskan resource yang cukup besar. Sehingga penggunaan wireshark di sini sangat diperlukan untuk menganalisis bandwidth pada paket yang diterima oleh client. Dari hasil pengukuran video dengan standar H.264 resolusi (720 x 540, dengan rata-rata 20 menit dalam pengambilan sampel, sebanyak 30 pengujian sampel streaming video menggunakan wireshark, diperoleh rata-rata throughput keseluruhan 0,343 Mbps, rata-rata throughput terendah 0,309 Mbps dan throughput tertinggi 0,372 Mbps. Dapat disimpulkan bahwa jika dihasilkan throughput yang lebih besar maka kualitas video streaming akan lebih baik, tetapi jika throughput dihasilkan semakin kecil maka kualitas video streaming akan menurun

  10. Arterial Stiffness: Recommendations and Standardization

    Science.gov (United States)

    Townsend, Raymond R.

    2017-01-01

    The use of arterial stiffness measurements in longitudinal cohorts of normal populations, hypertensive patients, diabetic patients, healthy elderly, and patients on hemodialysis have confirmed the value of this important measure of arterial health, and established its complementary role to measures of blood pressure. Its contribution to understanding cardiovascular and mortality risk beyond blood pressure measurements has moved measures of arterial stiffness into the ranks of factors such as elevated cholesterol, diabetes, and left ventricular hypertrophy in considering cardiovascular risk. The recent international collaboration's publication of reference ranges for normal people and those with hypertension, along with the American Heart Association's recent scientific statement on standardizing arterial stiffness measurements are important aspects to consider in future studies employing these valuable methods, particularly as interventions that not only lower blood pressure but improve arterial function are tested in the clinical arena. PMID:28275588

  11. Arterial Stiffness and Pharmacological Interventions – The TRanscend Arterial stiffNess Substudy (TRANS study

    Directory of Open Access Journals (Sweden)

    Jirar Topouchian

    2007-09-01

    Full Text Available Jirar Topouchian1, Ramzi El Feghali1, Bruno Pannier1, Shuyu Wang2, Feng Zhao3, Karel Smetana4, Koon Teo3, Roland Asmar11The CardioVascular Institute, Paris, France; 2Beijing Clinical Trial and Research Center, Beijing, China; 3Population Health Research Institute, Hamilton, Canada; 4Vojenska nemocnice Plzen, Pizen, Czech RepublicAbstract: The degree of arterial stiffness is correlated with the risk of cardiovascular diseases and it is a powerful predictor for morbidity and mortality. Studies have shown that arterial stiffness reduction is associated with an improvement in survival. Reduction of arterial stiffness by pharmacological drugs varies according to the drugs and doses used and duration of treatment. This effect on the arteries differs among the various classes of drugs and among individual drugs in the same class. Quantification of the stiffness and other properties of the arterial wall can be used to monitor the responses to therapy in individuals with hypertension and other cardiovascular diseases. These measures can then be used as surrogate markers for the risk of clinical events. Inhibition of the renin-angiotensin system (RAS is associated with an important decrease in cardiovascular risk. Findings from clinical trials support the hypothesis that the protective effects of RAS inhibition are partly independent from blood pressure reduction and related to several mechanisms including vascular protective effects. The aim of the TRanscend Arterial stiffNess Substudy (TRANS is to assess the effect of an angiotensin II receptor blocker (ARB, telmisartan, on the arterial stiffness in a subgroup of patients from the Telmisartan Randomized Assessment Study in aCE iNtolerant subjects with cardiovascular Disease (TRANSCEND trial. The TRANSCEND trial is an international, multicenter, randomized double blind placebo controlled trial of telmisartan that enrolled patients at high risk for cardiovascular events. Some clinical baseline data of the

  12. Lase Ultrasonic Web Stiffness tester

    Energy Technology Data Exchange (ETDEWEB)

    Tim Patterson, Ph.D., IPST at Ga Tech

    2009-01-12

    The objective is to provide a sensor that uses non-contact, laser ultrasonics to measure the stiffness of paper during the manufacturing process. This will allow the manufacturer to adjust the production process in real time, increase filler content, modify fiber refining and as result produce a quality product using less energy. The sensor operates by moving back and forth across the paper web, at pre-selected locations firing a laser at the sheet, measuring the out-of-plane velocity of the sheet then using that measurement to calculate sheet stiffness.

  13. Dynamic stiffness of suction caissons

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten; Andersen, Lars

    This report concerns the dynamic soil-structure interaction of steel suction caissons applied as foundations for offshore wind turbines. An emphasis is put on torsional vibrations and coupled sliding/rocking motion, and the influence of the foundation geometry and the properties of the surrounding...... soil is examined. The soil is simplified as a homogenous linear viscoelastic material and the dynamic stiffness of the suction caisson is expressed in terms of dimensionless frequency-dependent coefficients corresponding to the different degrees of freedom. The dynamic stiffness coefficients...

  14. Examining spectator motivations in Major League Baseball: A Comparison between senior and non-senior consumers

    Directory of Open Access Journals (Sweden)

    Junghwan Park

    2016-10-01

    Full Text Available The purpose of this study was to identify the differences in the motives between senior and non-senior sport consumers who attend sport events and to compare the effect of spectator motivation on sport consumption behaviors between senior and non-senior consumers. Multiple regression analyses were conducted to examine the relationship between motivation factors and sport consumption variables for senior and non- senior spectator groups. The results showed that both senior and non-senior spectators were commonly motivated by the following specific motives of escape, social interaction, physical skill and drama for attending a MLB game.

  15. Explicit Time-Stepping for Stiff ODEs

    CERN Document Server

    Eriksson, Kenneth; Logg, Anders; 10.1137/S1064827502409626

    2012-01-01

    We present a new strategy for solving stiff ODEs with explicit methods. By adaptively taking a small number of stabilizing small explicit time steps when necessary, a stiff ODE system can be stabilized enough to allow for time steps much larger than what is indicated by classical stability analysis. For many stiff problems the cost of the stabilizing small time steps is small, so the improvement is large. We illustrate the technique on a number of well-known stiff test problems.

  16. Shoulder Stiffness : Current Concepts and Concerns

    NARCIS (Netherlands)

    Itoi, Eiji; Arce, Guillermo; Bain, Gregory I.; Diercks, Ronald L.; Guttmann, Dan; Imhoff, Andreas B.; Mazzocca, Augustus D.; Sugaya, Hiroyuki; Yoo, Yon-Sik

    2016-01-01

    Shoulder stiffness can be caused by various etiologies such as immobilization, trauma, or surgical interventions. The Upper Extremity Committee of ISAKOS defined the term "frozen shoulder" as idiopathic stiff shoulder, that is, without a known cause. Secondary stiff shoulder is a term that should be

  17. Energy-Efficient Variable Stiffness Actuators

    NARCIS (Netherlands)

    Visser, Ludo C.; Carloni, Raffaella; Stramigioli, Stefano

    2011-01-01

    Variable stiffness actuators are a particular class of actuators that is characterized by the property that the apparent output stiffness can be changed independent of the output position. To achieve this, variable stiffness actuators consist of a number of elastic elements and a number of actuated

  18. Seniors' life histories and perceptions of illness.

    Science.gov (United States)

    Montbriand, Muriel J

    2004-03-01

    This life history research examined seniors' life experiences and perceived connections to illnesses. From a randomly selected sample of 190 seniors'interviews, 107 deemed to be the most expressive life stories were selected as the focus for this analysis. All seniors lived independently in a Canadian prairie city, were 60 years of age or older, Caucasian, European decent, had a chronic illness, and told of lives touched by the Great Depression and World War II. Given the paucity of research exploring seniors' life histories, these findings increase understanding of how life experiences shape seniors' identities. Four main themes emerged to describe seniors' lives: chaos, tragedy, quest, and romance. Findings reported here show that seniors with optimistic perceptions do not connect their life experiences with illnesses. Seniors with pessimistic perceptions frequently connect their life experiences with present illnesses and are most likely to remember past abuse and coping with abuse.

  19. Online resources for senior citizens

    CERN Document Server

    Sharpe, Charles C

    2006-01-01

    This book facilitates and expands Internet access and usage by seniors, assists them in finding the information they want and need, and contributes to their knowledge of the aging process and the challenges it presents by providing a list of online resources of particular interest to them.

  20. Negative stiffness in gear contact

    Directory of Open Access Journals (Sweden)

    Půst L.

    2015-12-01

    Full Text Available The tooth contact stiffness is very often included in dynamic mathematical models of gear drives. It is an important value for calculation of torsion eigenfrequencies as well as the dynamic properties of the whole transmission systems. Planetary gear drives have several advantages over simple parallel axis gears, especially due to theirs compact design and great torque-to-weight ratio caused by multiple parallel paths. However, the dimensional or mounting errors can cause that some planets have the tendency to take more load than the others. One of the ways how to improve load sharing is the application of flexible planetary pins or by using a free central wheel. However in such cases, the wheels motion is defined in one rotation coordinate and two translation coordinates — tangential and radial. The reaction force at radial change of axis distance is usually neglected. The focus of this contribution is to derive the stiffness of this radial connection and to analyse the influence of radial stiffness on planetary gear dynamics.

  1. Robotics Focused Capstone Senior Design Course

    Science.gov (United States)

    Rios-Gutierrez, Fernando; Alba-Flores, Rocio

    2017-01-01

    This work describes the educational experiences gained teaching the Senior Design I & II courses, a senior level, two-semester sequence in the Electrical Engineering (EE) program at Georgia Southern University (GSU). In particular, the authors present their experiences in using robotics as the main area to develop the capstone senior design,…

  2. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies...... stiffness. I introduce how to evaluate and distinguish between passive muscle stiffness and reflex-mediated stiffness in research and in clinical practice. Furthermore, I present ”the Portable Spasticity Assessment Device”, which was developed as a part of the PhD study. I discuss the validity......-mediated stiffness was considered a major problem. However, this study shows that significantly reduced RFD and increased passive muscle stiffness, rather than reflex-mediated stiffness, are the major contributors to impaired gait function in adults with CP, compared with neurologically healthy subjects. The third...

  3. Social work practice with LGBT seniors.

    Science.gov (United States)

    Gratwick, Steve; Jihanian, Lila J; Holloway, Ian W; Sanchez, Marisol; Sullivan, Kathleen

    2014-01-01

    The Los Angeles Gay & Lesbian Center began providing services to LGBT seniors in 2008. Since then, the Center's seniors program has grown to over 3,300 clients. It provides a variety of enrichment and support services with the overarching goal of empowering seniors to successfully age in place. This article outlines the service delivery program of the Center's Seniors Services Department and describes its successes and challenges in meeting the needs of diverse LGBT seniors. It offers future directions for social work practice, policy, and research with LGBT older adults.

  4. Voluntary control of human jaw stiffness.

    Science.gov (United States)

    Shiller, Douglas M; Houle, Guillaume; Ostry, David J

    2005-09-01

    Recent studies of human arm movement have suggested that the control of stiffness may be important both for maintaining stability and for achieving differences in movement accuracy. In the present study, we have examined the voluntary control of postural stiffness in 3D in the human jaw. The goal is to address the possible role of stiffness control in both stabilizing the jaw and in achieving the differential precision requirements of speech sounds. We previously showed that patterns of kinematic variability in speech are systematically related to the stiffness of the jaw. If the nervous system uses stiffness control as a means to regulate kinematic variation in speech, it should also be possible to show that subjects can voluntarily modify jaw stiffness. Using a robotic device, a series of force pulses was applied to the jaw to elicit changes in stiffness to resist displacement. Three orthogonal directions and three magnitudes of forces were tested. In all conditions, subjects increased the magnitude of jaw stiffness to resist the effects of the applied forces. Apart from the horizontal direction, greater increases in stiffness were observed when larger forces were applied. Moreover, subjects differentially increased jaw stiffness along a vertical axis to counteract disturbances in this direction. The observed changes in the magnitude of stiffness in different directions suggest an ability to control the pattern of stiffness of the jaw. The results are interpreted as evidence that jaw stiffness can be adjusted voluntarily, and thus may play a role in stabilizing the jaw and in controlling movement variation in the orofacial system.

  5. Macs For Seniors For Dummies

    CERN Document Server

    Chambers, Mark L

    2012-01-01

    You're never too old to fall in love—with your Mac! You took a while, but you are now the proud owner of your first Mac computer. Macs For Seniors For Dummies is just for you. This friendly, accessible guide walks you through choosing a Mac and learning how to use it. You'll find yourself falling head over heels for your Mac in no time. Macs For Seniors For Dummies introduces you to all the basics that you need to know: turning the Mac on and getting connected; using the keyboard and mouse; working with files and folders; navigate around the Mac desktop and OS X Lion; setting up an Inter

  6. Macs for seniors for dummies

    CERN Document Server

    Chambers, Mark L

    2009-01-01

    Over 50 and thinking about getting your first computer? A user-friendly Mac is a great choice, and Macs For Seniors For Dummies walks you through choosing one and learning to use it. You won't even need your grandchildren to help! Macs For Seniors For Dummies introduces you to all the basic things you may not have encountered before-how to use the keyboard and mouse, work with files and folders, navigate around the Mac OS X desktop, set up an Internet connection, and much more. You'll learn to:Choose the Mac that's right for you, set it up, run programs and manage files, and hook up a printerU

  7. Stiffness estimation of a parallel kinematic machine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper presents a simple yet comprehensive approach to quickly estimating the stiff-ness of a tripod-based parallel kinematic machine. This approach can be implemented in two steps. Inthe first step, the machine structure is decomposed into two substructures associated with the machineframe and parallel mechanism. The stiffness models of these two substructures are formulated bymeans of virtual work principle. This is followed by the second step that enables the stiffness model ofthe machine structure as a whole to be achieved by linear superposition. The 3D representations of themachine stiffness within the usable workspace are depicted and the contributions of different componentrigidities to the machine stiffness are discussed. The result is compared with that obtained through finiteelement analysis.

  8. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies......, which aimed to investigate: 1) The development of a clinical method to evaluate and distinguish neural (reflex mediated stiffness) and non-neural (passive muscle stiffness) components of muscle stiffness in adults with CP by objective and reliable measurements. 2) The association between increased...... passive muscle, muscle strength and gait function in adults with CP 3) The effect of resistance training and gait training accordingly on muscle strength, passive muscle stiffness and functional gait in adults with CP. The first part of the thesis defines reflex mediated stiffness and passive muscle...

  9. Numerical Analysis of Plastic Gear Stiffness

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper established practical 3-D gear models to study the stiffness influencing factors of a loaded gear by finite element method, such as friction parameters, material properties, and gear structures. The research shows that, in elastic deformation, gear stiffness increases when sliding friction ability of contact pair decreases;meanwhile, the gear structure, especially asymmetric design in gear's shaft direction will also decrease gear stiffness.

  10. Ambulatory arterial stiffness index: rationale and methodology

    OpenAIRE

    Dolan, Eamon; Li,Yan; Thijs, Lutgarde; McCormack, Patricia; Staessen, Jan A; O'Brien, Eoin; Stanton, Alice

    2006-01-01

    OBJECTIVES: Increased arterial stiffness is associated with the development of cardiovascular disease and may even predict its development at an early stage. Increased pulse pressure is seen as a marker of increased arterial stiffness and can be readily measured by ambulatory blood pressure monitoring. We propose another surrogate measure of arterial stiffness derived from ambulatory blood pressure monitoring that may predict cardiovascular mortality over and above pulse pressure, namely, the...

  11. A new approach to determine press stiffness

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Wanheim, Tarras

    2004-01-01

    A new procedure is proposed for measuring press stiffness, including separated horizontal and vertical loading of the press frame. The load can be eccentrically positioned for measuring rotational stiffnesses. Two loading devices and corresponding measuring equipment for registration of press...... deflections are designed. The press stiffness is presented as a 6 by 6 flexibility matrix. The approach has been tested by measuring the stiffness of a 5000 kN O-frame, ring element, hydraulic press, a 10000 kN O-frame, pillar element, hydraulic press and a 10000 kN O-frame, ring element mechanical press...

  12. WAY TO DETERMINE STIFFNESS FUNCTION OF STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    WANG De-ming; GAI Bing-zheng

    2005-01-01

    For calculating the stiffness function of a structure, the differential equation of the vibration of the structure was divided into the differential equation on the original stiffness function that was known, and Fredholm integral equation of the first kind on the undetermined stiffness function that was unknown. And the stable solutions of the integral equation, when the smooth factor was equal to zero, was solved by the extrapolation with p smooth factors. So the stiffness function of the structure is obtained. Applied examples show that the method is feasible and effective.

  13. Socio-economic Aspects of Senior Nutrition.

    OpenAIRE

    ONDRÁČKOVÁ, Miroslava

    2017-01-01

    The focus of the presented diploma thesis is to evaluate the knowledge of seniors in the field of healthy nutrition. It is furthermore important to find out, whether the seniors have enough relevant information about rational nutrition and which sources they would like to use to gather information about healthy nutrition. Socio-economic aspects, which lead to senior nutrition, are also monitored. A quantitative research strategy and an in-depth interview were used to fulfil the aim of the the...

  14. Nordic Seniors on the Move

    DEFF Research Database (Denmark)

    ”I believe that all people need to move about. Actually, some have difficulties in doing so. They stay in their home neighbourhoods where they’ve grown up and feel safe. I can understand that, but my wife and I, we didn’t want that. We are more open to new ideas.” This anthology is about seniors...... for identities, traditions, feelings of belonging, family and friends, health, images of old age, societal planning and policies, and even for religious attachment. The book presents a joint statement, intended for international scholars in the field, but also for Nordic policymakers and practitioners involved...

  15. Nordic Seniors on the Move

    DEFF Research Database (Denmark)

    on the move. In seven chapters, Nordic researchers from various disciplines, by means of ethnographic methods, attempt to comprehend the phenomenon of Nordic seniors who move to leisure areas in their own or in other countries. The number of people involved in this kind of migratory movement has grown...... for identities, traditions, feelings of belonging, family and friends, health, images of old age, societal planning and policies, and even for religious attachment. The book presents a joint statement, intended for international scholars in the field, but also for Nordic policymakers and practitioners involved...

  16. Culture Teaching in Senior English

    Institute of Scientific and Technical Information of China (English)

    徐晓飞

    2015-01-01

    The goal of English teaching is to have students master the English language as well as foster their cultural awareness,which will serve the communicative goal of language.However,many teachers of English now ignore the goal of the new curriculum and pay much attention to the language points and grammar while neglecting culture teaching.This essay concerns the problem of lacking culture teaching and the im-portance of cultural knowledge or information input in English teaching in senior school,in order to improve and perfect English teaching.

  17. SUPPORTING SENIOR CITIZENS TO LEARN IT SKILLS

    Directory of Open Access Journals (Sweden)

    Shigeki Yokoi

    2009-12-01

    Full Text Available Digital divide owing to age has become a major concern around the world, even in developed country, Japan. To combat the digital divide, a project named “e-namokun” aiming to help senior citizens use the Internet was started in Nagoya, Japan, which was a national first joint project run through government, universities, and NPO cooperation. In the project, nearly 2000 senior citizens have taken course of the software we developed. In relation with this project, we have been developing useful tools to support senior IT beginners. In the paper, we introduce the outline of the project and explain developed tools for senior citizens.

  18. Stiff person syndrome: a case report.

    Science.gov (United States)

    Kelly, Patricia A; Kuberski, Carolyn

    2014-08-01

    The case report features a patient who had a diagnosis of a common type of breast cancer with an uncommon neurologic syndrome. She had extreme pain and progressive stiffness with cognitive and functional decline. This article includes the pathogenesis and treatment options for a rare, but treatable, autoimmune disorder of malignancy called stiff person syndrome.

  19. Arterial Stiffness and Dialysis Calcium Concentration

    Directory of Open Access Journals (Sweden)

    Fabrice Mac-Way

    2011-01-01

    Full Text Available Arterial stiffness is the major determinant of isolated systolic hypertension and increased pulse pressure. Aortic stiffness is also associated with increased cardiovascular morbidity and mortality in patients with chronic kidney disease, hypertension, and general population. Hemodynamically, arterial stiffness results in earlier aortic pulse wave reflection leading to increased cardiac workload and decreased myocardial perfusion. Although the clinical consequence of aortic stiffness has been clearly established, its pathophysiology in various clinical conditions still remains poorly understood. The aim of the present paper is to review the studies that have looked at the impact of dialysis calcium concentration on arterial stiffness. Overall, the results of small short-term studies suggest that higher dialysis calcium is associated with a transient but significant increase in arterial stiffness. This calcium dependant increase in arterial stiffness is potentially explained by increased vascular smooth muscle tone of the conduit arteries and is not solely explained by changes in mean blood pressure. However, the optimal DCa remains to be determined, and long term studies are required to evaluate its impact on the progression of arterial stiffness.

  20. Determination of 6 stiffnesses for a press

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Eriksen, Morten; Wanheim, Tarras

    2000-01-01

    the workpiece will result in deflections of the press, which will decrease the tolerances of the component. At present, it is possible to measure the reaction forces from the workpiece, for instance by use of the model material technique as described in [1-2]. If the stiffness and clearances of the press...... is known too, the final dimensions can be predicted by divide the force by the stiffness and add the clearance. If the stiffness of the press is known, it is possible to optimize the orientation of the workpiece too, so the direction, in which the best tolerances is demanded, is equal to the direction...... in which the press has the highest stiffness. Furthermore, knowledge about the stiffnesses of all presses in a production system makes it possible to choose the press which best fit to a specific process....

  1. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    2016-01-01

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies......, which aimed to investigate: 1) The development of a clinical method to evaluate and distinguish neural (reflex mediated stiffness) and non-neural (passive muscle stiffness) components of muscle stiffness in adults with CP by objective and reliable measurements 2) The association between increased......, and good correlation to measurements from a stationary dynamometer. The second part of the thesis discusses the finding of a significant correlation between gait function, reduced rate of force development (RFD), and increased passive muscle stiffness in adults with CP. Previously, the reflex...

  2. Rolling Element Bearing Stiffness Matrix Determination (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Y.; Parker, R.

    2014-01-01

    Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.

  3. Stiffness Control of Surgical Continuum Manipulators

    Science.gov (United States)

    Mahvash, Mohsen; Dupont, Pierre E.

    2013-01-01

    This paper introduces the first stiffness controller for continuum robots. The control law is based on an accurate approximation of a continuum robot’s coupled kinematic and static force model. To implement a desired tip stiffness, the controller drives the actuators to positions corresponding to a deflected robot configuration that produces the required tip force for the measured tip position. This approach provides several important advantages. First, it enables the use of robot deflection sensing as a means to both sense and control tip forces. Second, it enables stiffness control to be implemented by modification of existing continuum robot position controllers. The proposed controller is demonstrated experimentally in the context of a concentric tube robot. Results show that the stiffness controller achieves the desired stiffness in steady state, provides good dynamic performance, and exhibits stability during contact transitions. PMID:24273466

  4. Genetic determinants of arterial stiffness: Results from the Rotterdam Study

    NARCIS (Netherlands)

    M.P.S. Sie (Mark)

    2007-01-01

    textabstractArterial stiffness increases with age. It is also associated with various diseases, such as diabetes mellitus and hypertension. Recently, arterial stiffness has also been found to independently predict cardiovascular disease. The pathogenesis of arterial stiffness, however, has n

  5. 12 CFR 619.9310 - Senior officer.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Senior officer. 619.9310 Section 619.9310 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM DEFINITIONS § 619.9310 Senior officer. The Chief Executive Officer, the Chief Operations Officer, the Chief Financial Officer, the Chief...

  6. Senior Volunteers: Helping Hands & Willing Workers.

    Science.gov (United States)

    Wessely, Michael

    1995-01-01

    Volunteers and other community-based assistants can relieve some of the financial burden brought on by school-budget cutbacks. This publication describes how enlisting the help of senior volunteers and workers benefits both children and seniors, and it presents some guidelines for implementation of intergeneration programs. The programs provide…

  7. Developing Senior Leaders for the Reserve Components

    Science.gov (United States)

    2017-01-01

    Without such internal efforts to “build a bench ” of future leaders, services will find that they have limited choices for senior leader positions. In...Annotated Bibliography, Greensboro, N.C.: Center for Creative Leadership, 1998. McGuire, Mark A., “Senior Officers and Strategic Leader Development

  8. Senior Military Colleges Meet At Virginia Tech

    OpenAIRE

    Lovegrove, Richard L.

    2003-01-01

    Representatives from the nation's six senior military colleges will hear from the Department of Defense and national Reserve Officer Training Corps (ROTC) commanders during the annual Senior Military Colleges Conference at Virginia Tech on Wednesday and Thursday, Sept. 17 and 18 at the Donaldson Brown Hotel and Conference Center.

  9. Resources for Developing Senior Faculty as Teachers.

    Science.gov (United States)

    Seal, Robert K.

    1993-01-01

    An annotated list of 38 resources is provided to help administrators, faculty developers, and faculty in designing effective renewal interventions for senior faculty. Topics include research on senior faculty, personnel policies (tenure, growth contracting), program strategies (mentoring, team teaching, motivation), and assessment of institutional…

  10. Stiff substrates enhance cultured neuronal network activity.

    Science.gov (United States)

    Zhang, Quan-You; Zhang, Yan-Yan; Xie, Jing; Li, Chen-Xu; Chen, Wei-Yi; Liu, Bai-Lin; Wu, Xiao-an; Li, Shu-Na; Huo, Bo; Jiang, Lin-Hua; Zhao, Hu-Cheng

    2014-08-28

    The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.

  11. Dynamic stiffness of suction caissons - vertical vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Ibsen, Lars Bo; Liingaard, M.; Andersen, Lars

    2006-12-15

    The dynamic response of offshore wind turbines are affected by the properties of the foundation and the subsoil. The purpose of this report is to evaluate the dynamic soil-structure interaction of suction caissons for offshore wind turbines. The investigation is limited to a determination of the vertical dynamic stiffness of suction caissons. The soil surrounding the foundation is homogenous with linear viscoelastic properties. The dynamic stiffness of the suction caisson is expressed by dimensionless frequency-dependent dynamic stiffness coefficients corresponding to the vertical degree of freedom. The dynamic stiffness coefficients for the foundations are evaluated by means of a dynamic three-dimensional coupled Boundary Element/Finite Element model. Comparisons are made with known analytical and numerical solutions in order to evaluate the static and dynamic behaviour of the Boundary Element/Finite Element model. The vertical frequency dependent stiffness has been determined for different combinations of the skirt length, Poisson's ratio and the ratio between soil stiffness and skirt stiffness. Finally the dynamic behaviour at high frequencies is investigated. (au)

  12. Accelerated Solutions for Transcendental Stiffness Matrix Eigenproblems

    Directory of Open Access Journals (Sweden)

    F.W. Williams

    1996-01-01

    Full Text Available This article outlines many existing and forthcoming methods that can be used alone, or in various combinations, to accelerate the solutions of the transcendental stiffness matrix eigenproblems that arise when the stiffness matrix is assembled from exact member stiffnesses, which are obtained by solving the member differential equations exactly. Thus distributed member mass and/or the flexural effect of axial loading are incorporated exactly, and the solutions are the natural frequencies for vibration problems or the critical load factors for buckling problems.

  13. Vascular Aging and Arterial Stiffness.

    Science.gov (United States)

    Mikael, Luana de Rezende; Paiva, Anelise Machado Gomes de; Gomes, Marco Mota; Sousa, Ana Luiza Lima; Jardim, Paulo César Brandão Veiga; Vitorino, Priscila Valverde de Oliveira; Euzébio, Maicon Borges; Sousa, Wátila de Moura; Barroso, Weimar Kunz Sebba

    2017-06-29

    Cardiovascular diseases (CVD) account annually for almost one third of all deaths worldwide. Among the CVD, systemic arterial hypertension (SAH) is related to more than half of those outcomes. Type 2 diabetes mellitus is an independent risk factor for SAH because it causes functional and structural damage to the arterial wall, leading to stiffness. Several studies have related oxidative stress, production of free radicals, and neuroendocrine and genetic changes to the physiopathogenesis of vascular aging. Indirect ways to analyze that aging process have been widely studied, pulse wave velocity (PWV) being considered gold standard to assess arterial stiffness, because there is large epidemiological evidence of its predictive value for cardiovascular events, and it requires little technical knowledge to be performed. A pulse wave is generated during each cardiac contraction and travels along the arterial bed until finding peripheral resistance or any bifurcation point, determining the appearance of a reflected wave. In young individuals, arteries tend to be more elastic, therefore, the reflected wave occurs later in the cardiac cycle, reaching the heart during diastole. In older individuals, however, the reflected wave occurs earlier, reaching the heart during systole. Because PWV is an important biomarker of vascular damage, highly valuable in determining the patient's global cardiovascular risk, we chose to review the articles on vascular aging in the context of cardiovascular risk factors and the tools available to the early identification of that damage. Resumo As doenças cardiovasculares são anualmente responsáveis por quase um terço do total de mortes no mundo. Dentre elas, a hipertensão arterial sistêmica (HAS) está relacionada com mais da metade desses desfechos. O diabetes mellitus tipo 2 é visto com um fator de risco independente para HAS por causar lesões funcionais e estruturais na parede arterial, ocasionando-lhe enrijecimento. Diversos estudos

  14. Stiff Neck, Torticollis, and Pseudotumor Cerebri

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-05-01

    Full Text Available Three prepubertal children diagnosed with pseudotumor cerebri and presenting with stiff neck and torticollis are reported from Schneider Children’s Medical Center, Sackler School of Medicine, Tel Aviv, Israel.

  15. Observed variations of monopile foundation stiffness

    DEFF Research Database (Denmark)

    Kallehave, Dan; Thilsted, C.L.; Diaz, Alberto Troya

    2015-01-01

    The soil-structure stiffness of monopile foundations for offshore wind turbines has a high impact on the fatigue loading during normal operating conditions. Thus, a robust design must consider the evolution of pile-soil stiffness over the lifetime of the wind farm. This paper present and discuss...... full-scale measurements obtained from one offshore wind turbine structure located within Horns Reef II offshore wind farm. Data are presented for a 2.5 years period and covers normal operating conditions and one larger storm event. A reduction of the pile-soil stiffness was observed during the storm...... events, followed by a complete regain to a pre-storm level when the storm subsided. In additional, no long term variations of the pile-soil stiffness was observed. The wind turbine is located in dense to very dense sand deposits....

  16. Strength and stiffness of engineering systems

    CERN Document Server

    Leckie, Frederick A

    2009-01-01

    This book on the stiffness and strength of engineering systems integrates a wide array of topics into a unified text, including plasticity, fracture, composite materials, energy approaches, and mechanics of microdevices (MEMs)..

  17. Vascular Stiffness in Insulin Resistance and Obesity

    Directory of Open Access Journals (Sweden)

    Guanghong eJia

    2015-08-01

    Full Text Available Obesity, insulin resistance, and type 2 diabetes are associated with a substantially increased prevalence of vascular fibrosis and stiffness, with attendant increased risk of cardiovascular and chronic kidney disease. Although the underlying mechanisms and mediators of vascular stiffness are not well understood, accumulating evidence supports the role of metabolic and immune dysregulation related to increased adiposity, activation of the renin angiotensin aldosterone system, reduced bioavailable nitric oxide, increased vascular extracellular matrix (ECM and ECM remodeling in the pathogenesis of vascular stiffness. This review will give a brief overview of the relationship between obesity, insulin resistance and increased vascular stiffness to provide a contemporary understanding of the proposed underlying mechanisms and potential therapeutic strategies.

  18. Stiff person syndrome and myasthenia gravis.

    Directory of Open Access Journals (Sweden)

    Saravanan P

    2002-01-01

    Full Text Available Association of stiff person syndrome, an immune related disorder of anterior horn cells and myasthenia gravis an endplate disorder with similar pathogenesis, is rare. This communication documents this association in the Indian literature for the first time.

  19. Determination of 6 stiffnesses for a press

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Eriksen, Morten; Wanheim, Tarras

    2000-01-01

    The industry is increasingly demanding for better tolerances at cold forged products caused by the tough competition at the market. Near net-shape or net-shape production save resources for machining and reduce therefore also the material costs. During the forming process, the reaction forces fro...... in which the press has the highest stiffness. Furthermore, knowledge about the stiffnesses of all presses in a production system makes it possible to choose the press which best fit to a specific process....... is known too, the final dimensions can be predicted by divide the force by the stiffness and add the clearance. If the stiffness of the press is known, it is possible to optimize the orientation of the workpiece too, so the direction, in which the best tolerances is demanded, is equal to the direction...

  20. Numerical assessment of the stiffness index.

    Science.gov (United States)

    Epstein, Sally; Vergnaud, Anne-Claire; Elliott, Paul; Chowienczyk, Phil; Alastruey, Jordi

    2014-01-01

    Elevated systemic vascular stiffness is associated with increased risk of cardiovascular disease. It has been suggested that the time difference between the two characteristic peaks of the digital volume pulse (DVP) measured at the finger using photoplethysmography is related to the stiffness of the arterial tree, and inversely proportional to the stiffness index (SI). However, the precise physical meaning of the SI and its relation to aortic pulse wave velocity (aPWV) is yet to be ascertained. In this study we investigated numerically the effect of changes in arterial wall stiffness, peripheral resistances, peripheral compliances or peripheral wave reflections on the SI and aPWV. The SI was calculated from the digital area waveform simulated using a nonlinear one-dimensional model of pulse wave propagation in a 75-artery network, which includes the larger arteries of the hand. Our results show that aPWV is affected by changes in aortic stiffness, but the SI is primarily affected by changes in the stiffness of all conduit vessels. Thus, the SI is not a direct substitute for aPWV. Moreover, our results suggest that peripheral reflections in the upper body delay the time of arrival of the first peak in the DVP. The second peak is predominantly caused by the impedance mismatch within the 75 arterial segments, rather than by peripheral reflections.

  1. Stiffness of Railway Soil-Steel Structures

    Science.gov (United States)

    Machelski, Czesław

    2015-12-01

    The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness) become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces), as in bridges. The analyzed cases show that the shell's span, geometry (static scheme) and the height of earth fill influence the stiffness of the structure. The soil-steel structure's characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  2. Office 2010 For Seniors For Dummies

    CERN Document Server

    Wempen, Faithe

    2010-01-01

    Clear, easy-to-understand instructions for seniors who want to get the most out of Microsoft Office 2010. Seniors are buying computers—both desktops and laptops—in record numbers to stay in touch with family and friends, connect with peers, research areas of interest, make purchases online, or learn a new skill. Assuming no prior knowledge of Microsoft Office, this book is aimed at seniors who are interested in maximizing the capabilities of Microsoft Word, Excel, PowerPoint, and Outlook. Written in large typeface and featuring enlarged figures and drawings to make the book easier to read, thi

  3. Classroom Language Environment and Seniors' Oral English

    Institute of Scientific and Technical Information of China (English)

    刘丽平

    2009-01-01

    The current situation of English teaching cannot keep pace with the requirements of the Senior High School Standards (the Ministry of Education, 2003). Due to the influences of the traditional teaching method, some English teachers still insist on the teacher-centered teaching approaches. The result is that there is less target language (TL) input and TL output in class, and senior students are weak in their oral English. This paper attempts to discuss the importance of language environment in classroom and find some appropriate ways to improving seniors' oral English.

  4. The stable stiffness triangle - drained sand during deformation cycles

    DEFF Research Database (Denmark)

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    2017-01-01

    Cyclic, drained sand stiffness was observed using the Danish triaxial appa- ratus. New, deformation dependant soil property (the stable stiffness triangle) was detected. Using the the stable stiffness triangle, secant stiffness of drained sand was plausible to predict (and control) even during ir...

  5. Senior Living: There's No Place Like Home

    Science.gov (United States)

    ... organizations; nearby senior centers; and civic, tribal, and religious organizations. They are there to help. Personal care: ... grooming. If that is the case with your parents, an aunt, uncle, or someone else, consider the ...

  6. Senior Living: Staying Positive and Moving Forward

    Science.gov (United States)

    ... Past Issues Feature: Senior Living Staying Positive and Moving Forward Past Issues / Summer 2009 Table of Contents ... page please turn Javascript on. For Juanita Kuhn, moving to an independent living facility is just the ...

  7. The Effect of Rib Shape on Stiffness.

    Science.gov (United States)

    Holcombe, Sven A; Wang, Stewart C; Grotberg, James B

    2016-11-01

    This study investigates the isolated effect of rib shape on the mechanical characteristics of ribs subjected to multiple forms of loading. It aims to measure the variation in stiffness due to shape that is seen throughout the population and, in particular, provide a tool for researchers to better understand the influence of shape on resulting stiffness. A previously published six-parameter shape model of the central axis of human ribs was used. It has been shown to accurately model the overall rib path using intrinsic geometric properties such as size, aspect ratio, and skewness, through shapes based on logarithmic spirals with high curvature continuity. In this study the model was fitted to 19,500 ribs from 989 adult female and male CT scans having demographic distributions matching the US adult population. Mechanical loading was simulated through a simplified finite element model aimed at isolating rib shape from other factors influencing mechanical response. Four loading scenarios were used representing idealized free and constrained loading conditions in axial (body-anterior) and lateral directions. Characteristic rib stiffness and maximum stress location were tracked as simulation output measures. Regression models of rib stiffness found that all shape model parameters added information when predicting stiffness under each loading condition, with their linear combination able to account for 95% of the population stiffness variation due to shape in midlevel ribs for free axial loading, and 92%-98% in other conditions. Full regression models including interactive terms explained up to 99% of population variability. Results allow researchers to better evaluate the differences in stiffness results that are obtained from physical testing by providing a framework with which to explain variation due to rib shape.

  8. Physical inactivity and arterial stiffness in COPD

    Directory of Open Access Journals (Sweden)

    Sievi NA

    2015-09-01

    Full Text Available Noriane A Sievi,1 Daniel Franzen,1 Malcolm Kohler,1,2 Christian F Clarenbach1 1Division of Pulmonology, University Hospital of Zurich, 2Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland Background: Arterial stiffness is an important predictor of cardiovascular risk besides classic cardiovascular risk factors. Previous studies showed that arterial stiffness is increased in patients with COPD compared to healthy controls and exercise training may reduce arterial stiffness. Since physical inactivity is frequently observed in patients with COPD and exercise training may improve arterial stiffness, we hypothesized that low daily physical activity may be associated with increased arterial stiffness. Methods: In 123 patients with COPD (72% men; mean [standard deviation] age: 62 [7.5] years; median [quartile] forced expiratory volume in 1 second 35 [27/65] %predicted, arterial stiffness was assessed by augmentation index (AI. Daily physical activity level (PAL was measured by an activity monitor (SenseWear Pro™ >1 week. The association between AI and PAL was investigated by univariate and multivariate regression analysis, taking into account disease-specific characteristics and comorbidities. Results: Patients suffered from moderate (35%, severe (32%, and very severe (33% COPD, and 22% were active smokers. Median (quartile PAL was 1.4 (1.3/1.5 and mean (standard deviation AI 26% (9.2%. PAL showed a negative association with AI (B=-9.32, P=0.017 independent of age, sex, blood pressure, and airflow limitation. Conclusion: In COPD patients, a higher PAL seems to favorably influence arterial stiffness and therefore may reduce cardiovascular risk. Clinical Trial Registration: www.ClinicalTrials.gov, NCT01527773 Keywords: activity monitor, airflow limitation, COPD, physical activity level

  9. Waves in geomaterials exhibiting negative stiffness behaviour

    Science.gov (United States)

    Esin, Maxim; Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Negative stiffness denotes the type of material behaviour when the force applied to the body decreases the body's deformation increases. Some geomaterials, for instance, rocks, demonstrate behaviour of this type at certain loads: during the compression tests the loading curves exhibit descending branch (post-peak softening). One of the possible mechanisms of the negative stiffness appearance in geomaterials is rotation of non-spherical grains. It is important to emphasize that in this case the descending branch may be reversible given that the testing machine is stiff enough (in general case it means an importance of boundary conditions). Existence of geomaterials with a negative modulus associated with rotations may have significant importance. In particular, important is understanding of the wave propagation in such materials. We study the stability of geomaterials with negative stiffness inclusions and wave propagation in it using two approaches: Cosserat continuum and discrete mass-spring models. In both cases we consider the rotational degrees of freedom in addition to the conventional translational ones. We show that despite non positiveness of the energy the materials with negative stiffness elements can be stable if certain conditions are met. In the case of Cosserat continuum the Cosserat shear modulus (the modulus relating the non-symmetrical part of shear stress and internal rotations) is allowed to assume negative values as long as its value does not exceed the value of the standard (positive) shear modulus. In the case of discrete mass-spring systems (with translational and rotational springs) the concentration of negative stiffness springs and the absolute values of negative spring stiffness are limited. The critical concentration when the system loses stability and the amplitude of the oscillations tends to infinity is equal to 1/2 and 3/5 for two- and three-dimensional cases respectively.

  10. Effect of Nanotechnology Instructions on Senior High School Students

    Science.gov (United States)

    Lu, Chow-Chin; Sung, Chia-Chi

    2011-01-01

    In this research, we cooperate with senior high school teachers to understand current nanotechnology model of senior high school nanotechnology curriculum in Taiwan. Then design senior high school nanotechnology (nano-tech) curriculum to teach 503 senior high school students. After teaching the nano-tech curriculum we use the "Nanotechnology…

  11. Effect of Nanotechnology Instructions on Senior High School Students

    Science.gov (United States)

    Lu, Chow-Chin; Sung, Chia-Chi

    2011-01-01

    In this research, we cooperate with senior high school teachers to understand current nanotechnology model of senior high school nanotechnology curriculum in Taiwan. Then design senior high school nanotechnology (nano-tech) curriculum to teach 503 senior high school students. After teaching the nano-tech curriculum we use the "Nanotechnology…

  12. Variable stiffness design of redundantly actuated planar rotational parallel mechanisms

    Institute of Scientific and Technical Information of China (English)

    Li Kangkang; Jiang Hongzhou; Cui Zuo; Huang Qun

    2017-01-01

    Redundantly actuated planar rotational parallel mechanisms (RAPRPMs) adapt to the requirements of robots under different working conditions by changing the antagonistic internal force to tune their stiffness. The geometrical parameters of the mechanism impact the performances of modulating stiffness. Analytical expressions relating stiffness and geometrical parameters of the mechanism were formulated to obtain the necessary conditions of variable stiffness. A novel method of variable stiffness design was presented to optimize the geometrical parameters of the mechanism. The stiffness variation with the internal force was maximized. The dynamic change of stiffness with the dynamic location of the mechanism was minimized, and the robustness of stiff-ness during the motion of the mechanism was ensured. This new approach to variable stiffness design can enable off-line planning of the internal force to avoid the difficulties of on-line control of the internal force.

  13. Enhancing Identity Development at Senior Service Colleges

    Science.gov (United States)

    2016-12-01

    to deal with other identity-challenging situations, such as organization- al change or transformation efforts, difficult ethical dilemmas , and...incur undue stress and health problems; or, succumb to ethical failure due to an inability to cope with the added responsibilities of senior...mid-level ranks to senior leadership. The more dis- identified an officer is to a role, the more likely that poor duty performance and ethical

  14. Single motor–variable stiffness actuator using bistable switching mechanisms for independent motion and stiffness control

    NARCIS (Netherlands)

    Groothuis, S.S.; Carloni, R.; Stramigioli, S.

    2016-01-01

    This paper presents a proof of concept of a variable stiffness actuator (VSA) that uses only one (high power) input motor. In general, VSAs use two (high power) motors to be able to control both the output position and the output stiffness, which possibly results in a heavy, and bulky system. In thi

  15. [Stiff-person syndrome and related autoantibodies].

    Science.gov (United States)

    Tomioka, Ryo; Tanaka, Keiko

    2013-04-01

    Central nervous system hyperexcitability disorders, known as stiff-man/person syndrome (SPS), are thought to be related to the regulatory disturbance of inhibitory synaptic transmission of motor neurons in the brainstem and spinal cord. SPS is characterized by stiffness and spasms of the axis and limbs and is divided into two clinical subgroups: classic SPS, which affects the lumbar, trunk, and proximal limb muscles, and SPS-plus syndrome. The latter comprises (1) the stiff-limb subtype, in which symptom is limited to the lower limbs; (2) jerking stiff-man syndrome, characterized by chronically progressive stiffness and myoclonus; and (3) acute-onset and progressive encephalomyelitis with rigidity and myoclonus. Almost 80% of patients with classic SPS harbor autoantibodies against glutamic acid decarboxylase 65 (GAD65). In approximately 30-40% of patients, SPS accompanies type I diabetes, and anti-GAD65 antibodies are detected frequently in type I diabetes. However, the antibody-recognizing epitopes might be different between SPS and diabetes. Other autoantibodies against glycine receptor α1 (12% of patients with SPS) and GABA(A)-receptor associated protein (70% of patients with SPS) have been reported. In paraneoplastic SPS, anti-amphiphysin antibodies have been shown in patients with breast cancer or small cell lung cancer. One case of mediastinal tumor with anti-gephyrin antibodies has also been reported. However, the roles of these autoantibodies in the pathomechanisms of SPS have not yet been elucidated.

  16. Big Bang nucleosynthesis with a stiff fluid

    CERN Document Server

    Dutta, Sourish

    2010-01-01

    Models that lead to a cosmological stiff fluid component, with a density $\\rho_S$ that scales as $a^{-6}$, where $a$ is the scale factor, have been proposed recently in a variety of contexts. We calculate numerically the effect of such a stiff fluid on the primordial element abundances. Because the stiff fluid energy density decreases with the scale factor more rapidly than radiation, it produces a relatively larger change in the primordial helium-4 abundance than in the other element abundances, relative to the changes produced by an additional radiation component. We show that the helium-4 abundance varies linearly with the density of the stiff fluid at a fixed fiducial temperature. Taking $\\rho_{S10}$ and $\\rho_{R10}$ to be the stiff fluid energy density and the standard density in relativistic particles, respectively, at $T = 10$ MeV, we find that the change in the primordial helium abundance is well-fit by $\\Delta Y_p = 0.00024(\\rho_{S10}/\\rho_{R10})$. The changes in the helium-4 abundance produced by ad...

  17. Torso flexion modulates stiffness and reflex response.

    Science.gov (United States)

    Granata, K P; Rogers, E

    2007-08-01

    Neuromuscular factors that contribute to spinal stability include trunk stiffness from passive and active tissues as well as active feedback from reflex response in the paraspinal muscles. Trunk flexion postures are a recognized risk factor for occupational low-back pain and may influence these stabilizing control factors. Sixteen healthy adult subjects participated in an experiment to record trunk stiffness and paraspinal muscle reflex gain during voluntary isometric trunk extension exertions. The protocol was designed to achieve trunk flexion without concomitant influences of external gravitational moment, i.e., decouple the effects of trunk flexion posture from trunk moment. Systems identification analyses identified reflex gain by quantifying the relation between applied force disturbances and time-dependent EMG response in the lumbar paraspinal muscles. Trunk stiffness was characterized from a second order model describing the dynamic relation between the force disturbances versus the kinematic response of the torso. Trunk stiffness increased significantly with flexion angle and exertion level. This was attributed to passive tissue contributions to stiffness. Reflex gain declined significantly with trunk flexion angle but increased with exertion level. These trends were attributed to correlated changes in baseline EMG recruitment in the lumbar paraspinal muscles. Female subjects demonstrated greater reflex gain than males and the decline in reflex gain with flexion angle was greater in females than in males. Results reveal that torso flexion influences neuromuscular factors that control spinal stability and suggest that posture may contribute to the risk of instability injury.

  18. A Novel Variable Stiffness Mechanism Capable of an Infinite Stiffness Range and Unlimited Decoupled Output Motion

    Directory of Open Access Journals (Sweden)

    Stefan Groothuis

    2014-06-01

    Full Text Available In this paper, a novel variable stiffness mechanism is presented, which is capable of achieving an output stiffness with infinite range and an unlimited output motion, i.e., the mechanism output is completely decoupled from the rotor motion, in the zero stiffness configuration. The mechanism makes use of leaf springs, which are engaged at different positions by means of two movable supports, to realize the variable output stiffness. The Euler–Bernoulli leaf spring model is derived and validated through experimental data. By shaping the leaf springs, it is shown that the stiffness characteristic of the mechanism can be changed to fulfill different application requirements. Alternative designs can achieve the same behavior with only one leaf spring and one movable support pin.

  19. Knee stiffness following anterior cruciate ligament reconstruction: the incidence and associated factors of knee stiffness following anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Robertson, G A J; Coleman, S G S; Keating, J F

    2009-08-01

    We reviewed 100 patients retrospectively following primary ACL reconstruction with quadruple hamstring autografts to evaluate the incidence and factors associated with postoperative stiffness. Stiffness was defined as any loss of motion using the contra-lateral leg as a control. The median delay between injury and operation was 15 months. The incidence of stiffness was 12% at 6 months post-reconstruction. Both incomplete attendance at physiotherapy (pAnterior knee pain was also associated with the stiffness (p<0.029). Factors that failed to show a significant association with the stiffness included associated MCL sprain at injury (p=0.32), post-injury stiffness (p=1.00) and concomitant menisectomy at reconstruction (p=0.54). Timing of surgery also did not appear to influence the onset of stiffness (median delays: 29 months for stiff patients; 14 months for non-stiff patients). The rate of stiffness fell to 5% at 12 months postreconstruction, without operative intervention.

  20. Electrochemical stiffness in lithium-ion batteries

    Science.gov (United States)

    Tavassol, Hadi; Jones, Elizabeth M. C.; Sottos, Nancy R.; Gewirth, Andrew A.

    2016-11-01

    Although lithium-ion batteries are ubiquitous in portable electronics, increased charge rate and discharge power are required for more demanding applications such as electric vehicles. The high-rate exchange of lithium ions required for more power and faster charging generates significant stresses and strains in the electrodes that ultimately lead to performance degradation. To date, electrochemically induced stresses and strains in battery electrodes have been studied only individually. Here, a new technique is developed to probe the chemomechanical response of electrodes by calculating the electrochemical stiffness via coordinated in situ stress and strain measurements. We show that dramatic changes in electrochemical stiffness occur due to the formation of different graphite-lithium intercalation compounds during cycling. Our analysis reveals that stress scales proportionally with the lithiation/delithiation rate and strain scales proportionally with capacity (and inversely with rate). Electrochemical stiffness measurements provide new insights into the origin of rate-dependent chemomechanical degradation and the evaluation of advanced battery electrodes.

  1. Red wine, arterial stiffness and central hemodynamics.

    Science.gov (United States)

    Karatzi, Kalliopi; Papaioannou, Theodore G; Papamichael, Christos; Lekakis, John; Stefanadis, Christodoulos; Zampelas, Antonis

    2009-01-01

    Red wine is considered to reduce cardiovascular risk and decrease peripheral systolic and diastolic blood pressure. Central aortic pressures are often more sensitive clinical and prognostic factors than peripheral pressures, while arterial stiffness is an independent prognostic factor for cardiovascular events. Great efforts are being made to find natural sources of improving health. In order to clarify the mechanisms under which a widely used drink, like red wine, is affecting heart and vessels, we aimed to review the available data regarding the effects of red wine on arterial stiffness, wave reflections and central blood pressures. The effect of red wine on central hemodynamics has been poorly explored with divergent results. Possible consequences of acute and long-term intake on arterial stiffness, wave reflections and central pressures are not clear. This might make someone skeptical when suggesting the consumption of a glass of red wine, although its cardioprotective actions (when moderately consumed) are already shown from epidemiological studies.

  2. Dynamic stiffness model of spherical parallel robots

    Science.gov (United States)

    Cammarata, Alessandro; Caliò, Ivo; D`Urso, Domenico; Greco, Annalisa; Lacagnina, Michele; Fichera, Gabriele

    2016-12-01

    A novel approach to study the elastodynamics of Spherical Parallel Robots is described through an exact dynamic model. Timoshenko arches are used to simulate flexible curved links while the base and mobile platforms are modelled as rigid bodies. Spatial joints are inherently included into the model without Lagrangian multipliers. At first, the equivalent dynamic stiffness matrix of each leg, made up of curved links joined by spatial joints, is derived; then these matrices are assembled to obtain the Global Dynamic Stiffness Matrix of the robot at a given pose. Actuator stiffness is also included into the model to verify its influence on vibrations and modes. The latter are found by applying the Wittrick-Williams algorithm. Finally, numerical simulations and direct comparison to commercial FE results are used to validate the proposed model.

  3. Variable stiffness and damping magnetorheological isolator

    Institute of Scientific and Technical Information of China (English)

    Yang ZHOU; Xingyu WANG; Xianzhou ZHANG; Weihua LI

    2009-01-01

    This paper presents the development and characterization of a magnetorheological (MR) fluid-based variable stiffness and damping isolator. The prototype of the MR fluid isolator is fabricated, and its dynamic behavior is measured under various applied magnetic fields. The parameters of the model under various magnetic fields are identified, and the dynamic perfor-mance of the isolator is evaluated in simulation. Experi-mental results indicate that both the stiffness and damping capability of the developed MR isolator can be controlled by an external magnetic field.

  4. Modulation of fixation stiffness from flexible to stiff in a rat model of bone healing.

    Science.gov (United States)

    Bartnikowski, Nicole; Claes, Lutz E; Koval, Lidia; Glatt, Vaida; Bindl, Ronny; Steck, Roland; Ignatius, Anita; Schuetz, Michael A; Epari, Devakara R

    2016-11-14

    Background and purpose - Constant fixator stiffness for the duration of healing may not provide suitable mechanical conditions for all stages of bone repair. We therefore investigated the influence of stiffening fixation on callus stiffness and morphology in a rat diaphyseal osteotomy model to determine whether healing time was shortened and callus stiffness increased through modulation of fixation from flexible to stiff. Material and methods - An external unilateral fixator was applied to the osteotomized femur and stiffened by decreasing the offset of the inner fixator bar at 3, 7, 14, and 21 days after operation. After 5 weeks, the rats were killed and healing was evaluated with mechanical, histological, and microcomputed tomography methods. Constant fixation stiffness control groups with either stiff or flexible fixation were included for comparison. Results - The callus stiffness of the stiff group and all 4 experimental groups was greater than in the flexible group. The callus of the flexible group was larger but contained a higher proportion of unmineralized tissue and cartilage. The stiff and modulated groups (3, 7, 14, and 21 days) all showed bony bridging at 5 weeks, as well as signs of callus remodeling. Stiffening fixation at 7 and 14 days after osteotomy produced the highest degree of callus bridging. Bone mineral density in the fracture gap was highest in animals in which the fixation was stiffened after 14 days. Interpretation - The predicted benefit of a large robust callus formed through early flexible fixation could not be shown, but the benefits of stabilizing a flexible construct to achieve timely healing were demonstrated at all time points.

  5. "If We Are Going to Include Them We Have to Do It before We Die": Norwegian Seniors' Views of Including Seniors with Intellectual Disability in Senior Centres

    Science.gov (United States)

    Ingvaldsen, Anne Kristin; Balandin, Susan

    2011-01-01

    Background: Concepts of inclusion and participation are at the core of both international and Norwegian policy for people with intellectual disability. The aim of this study was to identify senior centre users' views of the barriers and solutions to the inclusion of seniors with intellectual disability in community senior centres. Method: Thirty…

  6. "Stiffness has different meanings, I think, to everyone": examining stiffness from the perspective of people living with rheumatoid arthritis.

    Science.gov (United States)

    Orbai, Ana-Maria; Smith, Katherine C; Bartlett, Susan J; De Leon, Elaine; Bingham, Clifton O

    2014-11-01

    Stiffness is a well-recognized symptom of rheumatoid arthritis (RA). It is frequently queried during clinic visits as an indicator of disease activity and was included in the 1961 and 1987 RA classification criteria. Little is known about how people with RA experience stiffness and its impact on their lives. We conducted 4 focus groups including 20 people with RA (4-6 participants per group) from 1 academic clinical practice and 1 private practice to generate accounts of stiffness experiences. Qualitative inductive thematic data analysis was conducted. Five overarching themes were identified: relationship of stiffness with other symptoms, exacerbating or alleviating factors and self-management, stiffness timing and location, individual meanings of stiffness experiences, and impact of stiffness on daily life. Focus group discussions revealed individual stiffness experiences as diverse and complex. Several stiffness features were endorsed by a majority of participants, but few, if any, were universally experienced; thus, the significance of stiffness as an expression of the disease varied widely. Discussions yielded descriptions of how individual limits imposed by RA in general and stiffness in particular may change over time and were intertwined with adaptations to preserve participation in valued life activities. These results concerning the diversity of the stiffness experience, consequential adaptations, and its impact suggest that a more individualized approach to stiffness measurement may be needed to improve stiffness assessments. Copyright © 2014 by the American College of Rheumatology.

  7. Plant fibre composites - porosity and stiffness

    DEFF Research Database (Denmark)

    Madsen, Bo; Thygesen, Anders; Lilholt, Hans

    2009-01-01

    Plant fibre composites contain typically a relatively large amount of porosity which influences their performance. A model, based on a modified rule of mixtures, is presented to include the influence of porosity on the composite stiffness. The model integrates the volumetric composition of the co......Plant fibre composites contain typically a relatively large amount of porosity which influences their performance. A model, based on a modified rule of mixtures, is presented to include the influence of porosity on the composite stiffness. The model integrates the volumetric composition...... of the composites with their mechanical properties. The fibre weight fraction is used as an independent parameter to calculate the complete volumetric composition. A maximum obtainable stiffness of the composites is calculated at a certain transition fibre weight fraction, which is characterised by a best possible...... combination of high fibre volume fraction and low porosity. The model is validated with experimental data from the literature on several types of composites. A stiffness diagram is presented to demonstrate that the calculations can be used for tailoring and design of composites with a given profile...

  8. [Anaesthetic management of Stiff Man syndrome].

    Science.gov (United States)

    Marín, T; Hernando, D; Kinast, N; Churruca, I; Sabate, S

    2015-04-01

    Stiff Man syndrome or stiff-person syndrome is a rare autoimmune disorder. It is characterized by increased axial muscular tone and limb musculature, and painful spasms triggered by stimulus. The case is presented of a 44-year-old man with stiff-person syndrome undergoing an injection of botulinum toxin in the urethral sphincter under sedation. Before induction, all the surgical team were ready in order to minimise the anaesthetic time. The patient was monitored by continuous ECG, SpO2 and non-invasive blood pressure. He was induced with fractional dose of propofol 150 mg, fentanyl 50 μg and midazolam 1mg. Despite careful titration, the patient had an O2 saturation level of 90%,which was resolved by manual ventilation. There was no muscle rigidity or spasm during the operation. Post-operative recovery was uneventful and the patient was discharged 2 days later. A review of other cases is presented. The anaesthetic concern in patients with stiff-person syndrome is the interaction between the anaesthetic agents, the preoperative medication, and the GABA system. For a safe anaesthetic management, total intravenous anaesthesia is recommended instead of inhalation anaesthetics, as well as the close monitoring of the respiratory function and the application of the electrical nerve stimulator when neuromuscular blockers are used.

  9. Stiff directed lines in random media.

    Science.gov (United States)

    Boltz, Horst-Holger; Kierfeld, Jan

    2013-07-01

    We investigate the localization of stiff directed lines with bending energy by a short-range random potential. We apply perturbative arguments, Flory scaling arguments, a variational replica calculation, and functional renormalization to show that a stiff directed line in 1+d dimensions undergoes a localization transition with increasing disorder for d>2/3. We demonstrate that this transition is accessible by numerical transfer matrix calculations in 1+1 dimensions and analyze the properties of the disorder-dominated phase in detail. On the basis of the two-replica problem, we propose a relation between the localization of stiff directed lines in 1+d dimensions and of directed lines under tension in 1+3d dimensions, which is strongly supported by identical free-energy distributions. This shows that pair interactions in the replicated Hamiltonian determine the nature of directed line localization transitions with consequences for the critical behavior of the Kardar-Parisi-Zhang equation. We support the proposed relation to directed lines via multifractal analysis, revealing an analogous Anderson transition-like scenario and a matching correlation length exponent. Furthermore, we quantify how the persistence length of the stiff directed line is reduced by disorder.

  10. Non-singular inhomogeneous stiff fluid cosmology

    CERN Document Server

    Fernández-Jambrina, L

    2009-01-01

    In this talk we show a stiff fluid solution of the Einstein equations for a cylindrically symmetric spacetime. The main features of this metric are that it is non-separable in comoving coordinates for the congruence of the worldlineS of the fluid and that it yields regular curvature invariants.

  11. Monitoring the Bending Stiffness of DNA

    Science.gov (United States)

    Yuan, Chongli; Lou, Xiongwen; Rhoades, Elizabeth; Chen, Huimin; Archer, Lynden

    2007-03-01

    In eukaryotic cells, the accessibility of genomic sequences provides an inherent regulation mechanism for gene expression through variations in bending stiffness encoded by the nucleic acid sequence. Cyclization of dsDNA is the prevailing method for determining DNA bending stiffness. Recent cyclization data for short dsDNA raises several fundamental questions about the soundness of the cyclization method, particularly in cases where the probability of highly bent DNA conformations is low. We herein evaluate the role of T4 DNA ligase in the cyclization reaction by inserting an environmental sensitive base analogue, 2-amino purine, to the DNA molecule. By monitoring the 2-AP fluorescence under standard cyclization conditions, it is found that in addition to trapping highly-bent cyclic DNA conformations, T4 DNA ligase enhances the apparent base pair flip out rate, thus exaggerating the measured flexibility. This result is further confirmed using fluorescence anisotropy experiments. We show that fluorescence resonance energy transfer (FRET) measurements on suitably labeled dsDNA provides an alternative approach for quantifying the bending stiffness of short fragments. DNA bending stiffness results obtained using FRET are compared with literature values.

  12. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies...

  13. Influence of footings stiffness on punching resistance

    Directory of Open Access Journals (Sweden)

    Ĺudovít Fillo

    2016-03-01

    Full Text Available The presented paper brings new aspects of punching resistance due to influence of footing stiffness and consequential ground stresses distribution. Diagrams of design load versus effective depth were created coming from new design criteria which depend on the maximum punching resistance defined from shear-bending failure and on the maximum punching resistance defined from crushing of concrete struts.

  14. Improved Stiff ODE Solvers for Combustion CFD

    Science.gov (United States)

    Imren, A.; Haworth, D. C.

    2016-11-01

    Increasingly large chemical mechanisms are needed to predict autoignition, heat release and pollutant emissions in computational fluid dynamics (CFD) simulations of in-cylinder processes in compression-ignition engines and other applications. Calculation of chemical source terms usually dominates the computational effort, and several strategies have been proposed to reduce the high computational cost associated with realistic chemistry in CFD. Central to most strategies is a stiff ordinary differential equation (ODE) solver to compute the change in composition due to chemical reactions over a computational time step. Most work to date on stiff ODE solvers for computational combustion has focused on backward differential formula (BDF) methods, and has not explicitly considered the implications of how the stiff ODE solver couples with the CFD algorithm. In this work, a fresh look at stiff ODE solvers is taken that includes how the solver is integrated into a turbulent combustion CFD code, and the advantages of extrapolation-based solvers in this regard are demonstrated. Benefits in CPU time and accuracy are demonstrated for homogeneous systems and compression-ignition engines, for chemical mechanisms that range in size from fewer than 50 to more than 7,000 species.

  15. Seniority Number in Valence Bond Theory.

    Science.gov (United States)

    Chen, Zhenhua; Zhou, Chen; Wu, Wei

    2015-09-01

    In this work, a hierarchy of valence bond (VB) methods based on the concept of seniority number, defined as the number of singly occupied orbitals in a determinant or an orbital configuration, is proposed and applied to the studies of the potential energy curves (PECs) of H8, N2, and C2 molecules. It is found that the seniority-based VB expansion converges more rapidly toward the full configuration interaction (FCI) or complete active space self-consistent field (CASSCF) limit and produces more accurate PECs with smaller nonparallelity errors than its molecular orbital (MO) theory-based analogue. Test results reveal that the nonorthogonal orbital-based VB theory provides a reverse but more efficient way to truncate the complete active Hilbert space by seniority numbers.

  16. Regional Senior Tourism Marketing Strategy Research

    Directory of Open Access Journals (Sweden)

    Qi Zhang

    2013-05-01

    Full Text Available In this study, we have a research of the regional senior tourism marketing strategy. The father of modern marketing p.m. Philip once pointed out: The phenomenon of people seems very fierce market competition, hides a deeper phenomenon that is service competition is the nature of competition in the market, excellent service, not to mention the excellent marketing. The importance of service marketing have become increasingly prominent, want to invincible in market competition, service enterprise will from the whole effort, flexible use various strategies to create a competitive advantages, especially well service marketing work, so as to win in the competition. Based on the background of senior tourism market, adopted for the study of integrating theory with practice, pointing out the research method of the implementation of regional tourism marketing strategy for today's senior tourism market will create new competitive advantage of strategic significance.

  17. ON THE STIFFNESS OF DEMINERALIZED DENTIN MATRICES

    Science.gov (United States)

    Ryou, Heonjune; Turco, Gianluca; Breschi, Lorenzo; Tay, Franklin R.; Pashley, David H.; Arola, Dwayne

    2015-01-01

    Resin bonding to dentin requires the use of self-etching primers or acid etching to decalcify the surface and expose a layer of collagen fibrils of the dentin matrix. Acid-etching reduces the stiffness of demineralized dentin from approximately 19 GPa to 1 MPa, requiring that it floats in water to prevent it from collapsing during bonding procedures. Several publications show that crosslinking agents like gluteraladehyde, carbodiimide or grape seed extract can stiffen collagen and improve resin-dentin bond strength. Objective The objective was to assess a new approach for evaluating the changes in stiffness of decalcified dentin by polar solvents and a collagen cross-linker. Methods Fully demineralized dentin beams and sections of etched coronal dentin were subjected to indentation loading using a cylindrical flat indenter in water, and after treatment with ethanol or ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). The stiffness was measured as a function of strain and as a function of loading rate from 1 to 50 µm/sec. Results At a strain of 0.25% the elastic modulus of the fully demineralized dentin was approximately 0.20 MPa. It increased to over 0.90 MPa at strains of 1%. Exposure to ethanol caused an increase in elastic modulus of up to four times. Increasing the loading rate from 1 to 50 µm/sec caused an increase in the apparent modulus of up to three times in both water and ethanol. EDC treatment caused increases in the stiffness in fully demineralized samples and in acid-etched demineralized dentin surfaces in situ. Significance Changes in the mechanical behavior of demineralized collagen matrices can be measured effectively under hydration via indentation with cylindrical flat indenters. This approach can be used for quantifying the effects of bonding treatments on the properties of decalcified dentin after acid etching, as well as to follow the loss of stiffness over time due to enzymatic degradation. PMID:26747822

  18. Stiffness of lipid monolayers with phase coexistence.

    Science.gov (United States)

    Caruso, Benjamín; Mangiarotti, Agustín; Wilke, Natalia

    2013-08-27

    The surface dilational modulus--or compressibility modulus--has been previously studied for monolayers composed of pure materials, where a jump in this modulus was related with the onset of percolation as a result of the establishment of a connected structure at the molecular level. In this work, we focused on monolayers composed of two components of low lateral miscibility. Our aim was to investigate the compressibility of mixed monolayers at pressures and compositions in the two-phase region of the phase diagram, in order to analyze the effect of the mechanical properties of each phase on the stiffness of the composite. In nine different systems with distinct molecular dipoles and charges, the stiffness of each phase and the texture at the plane of the monolayer were studied. In this way, we were able to analyze the general compressibility of two-phase lipid monolayers, regardless of the properties of their constituent parts. The results are discussed in the light of the following two hypotheses: first, the stiffness of the composite could be dominated by the stiffness of each phase as a weighted sum according to the percentage of each phase area, regardless of the distribution of the phases in the plane of the monolayer. Alternatively, the stiffness of the composite could be dominated by the mechanical properties of the continuous phase. Our results were better explained by this latter proposal, as in all the analyzed mixtures it was found that the mechanical properties of the percolating phase were the determining factors. The value of the compression modulus was closer to the value of the connected phase than to that of the dispersed phase, indicating that the bidimensional composites displayed mechanical properties that were related to the properties of each phases in a rather complex manner.

  19. Facebook and Twitter For Seniors For Dummies

    CERN Document Server

    Collier, Marsha

    2010-01-01

    A fun and easy social media guide for the over-55 set. People over 55 were the fastest-growing user group on Facebook in the first half of 2009, and they're flocking to Twitter at a faster rate than their under-20 grandchildren. From basic information about establishing an Internet connection to rediscovering old friends, sharing messages and photos, and keeping in touch instantly with Twitter, this book by online expert Marsha Collier helps seniors jump right into social media.: Seniors are recognizing the communication possibilities of Facebook and Twitter and are signing up in record number

  20. A review on in situ stiffness adjustment methods in MEMS

    Science.gov (United States)

    de Laat, M. L. C.; Pérez Garza, H. H.; Herder, J. L.; Ghatkesar, M. K.

    2016-06-01

    In situ stiffness adjustment in microelectromechanical systems is used in a variety of applications such as radio-frequency mechanical filters, energy harvesters, atomic force microscopy, vibration detection sensors. In this review we provide designers with an overview of existing stiffness adjustment methods, their working principle, and possible adjustment range. The concepts are categorized according to their physical working principle. It is concluded that the electrostatic adjustment principle is the most applied method, and narrow to wide ranges in stiffness can be achieved. But in order to obtain a wide range in stiffness change, large, complex devices were designed. Mechanical stiffness adjustment is found to be a space-effective way of obtaining wide changes in stiffness, but these methods are often discrete and require large tuning voltages. Stiffness adjustment through stressing effects or change in Young’s modulus was used only for narrow ranges. The change in second moment of inertia was used for stiffness adjustment in the intermediate range.

  1. Laterality and imbalance of muscle stiffness relate to personality.

    Science.gov (United States)

    Nakaya, Naoki; Kumano, Hiroaki; Minoda, Keiji; Kanazawa, Motoyori; Fukudo, Shin

    2004-01-01

    The authors' purpose in this study was to test the hypothesis that laterality and imbalance of muscle stiffness relate to personality. The authors selected 23 healthy volunteers and divided them into two groups based on the predominance of muscle stiffness on the left or right side. Imbalance of muscle stiffness was calculated as the absolute value of the difference of muscle stiffness between the right and left sides. The authors evaluated personality with the Japanese version of the Eysenck Personality Questionnaire. Subjects with left predominant muscle stiffness of the rectal abdominis had significantly higher neuroticism score than those with right predominant muscle stiffness. Subjects with more imbalance of muscle stiffness in the latissimus dorsi and in the trapezius had significantly higher neuroticism and psychoticism scores than those with less imbalance. The findings suggest that laterality and imbalance of muscle stiffness relate to personality.

  2. 76 FR 80902 - Senior Executive Service; Performance Review Board; Members

    Science.gov (United States)

    2011-12-27

    ... on performance appraisals assigned to individual members of the agency's Senior Executive Service... FURTHER INFORMATION CONTACT: Tonya Turner, Deputy Associate Director for Human Resources, Court Services... SUPERVISION AGENCY FOR THE DISTRICT OF COLUMBIA Senior Executive Service; Performance Review Board;...

  3. 76 FR 81998 - Senior Executive Service Performance Review Board Membership

    Science.gov (United States)

    2011-12-29

    ... Service PRB. The PRB reviews and evaluates the initial appraisal of a senior executive's performance by... Risinger, Human Resources Director, Federal Housing Finance Agency; and Joel R. Schapira, Deputy General... HEALTH REVIEW COMMISSION Senior Executive Service Performance Review Board Membership...

  4. How Crouch Gait Can Dynamically Induce Stiff-Knee Gait

    NARCIS (Netherlands)

    Van der Krogt, M.M.; Bregman, D.J.J.; Wisse, M.; Doorenbosch, C.A.M.; Harlaar, J.; Collins, S.H.

    Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on

  5. How Crouch Gait Can Dynamically Induce Stiff-Knee Gait

    NARCIS (Netherlands)

    Van der Krogt, M.M.; Bregman, D.J.J.; Wisse, M.; Doorenbosch, C.A.M.; Harlaar, J.; Collins, S.H.

    Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on

  6. A novel energy-efficient rotational variable stiffness actuator

    NARCIS (Netherlands)

    Rao, Shodhan; Carloni, Raffaella; Stramigioli, Stefano

    2011-01-01

    This paper presents the working principle, the design and realization of a novel rotational variable stiffness actuator, whose stiffness can be varied independently of its output angular position. This actuator is energy-efficient, meaning that the stiffness of the actuator can be varied by keeping

  7. A novel energy-efficient rotational variable stiffness actuator

    NARCIS (Netherlands)

    Rao, S.; Carloni, Raffaella; Stramigioli, Stefano

    This paper presents the working principle, the design and realization of a novel rotational variable stiffness actuator, whose stiffness can be varied independently of its output angular position. This actuator is energy-efficient, meaning that the stiffness of the actuator can be varied by keeping

  8. Senior Health: Older Adults and Newer Technology

    Science.gov (United States)

    ... into plain language by Helen Osborne of Health Literacy Consulting Click here for optional PDF format. Requires Adobe Acrobat Reader . Many seniors, aged 65 and over, have diseases which cause disability. Some of these, such as diabetes, obesity, and severe peripheral vascular disease, can result ...

  9. Silver Gaming: Serious Fun for Seniors?

    NARCIS (Netherlands)

    Loos, E.; Zonneveld, A.; Zhou, J.; Salvendy, G.

    2016-01-01

    This exploratory qualitative study provides insight into the role that exergames play for seniors. 15 participants (aged 53-78) engaged in playing Your Shape Fitness Evolved 2 on the Xbox 360 Kinect, after which we conducted a semi-structured interview with each participant. We found that in all cas

  10. Senior Games as Serious Sport Tourism

    Science.gov (United States)

    Heo, Jimmoo; King, Carina

    2009-01-01

    Stebbins (1992) defined serious leisure as the systematic pursuit of amateur, hobbyist, or volunteer activity that is substantial and interesting for the participants involved. This study investigated associations between serious leisure and sport tourism using Indiana Senior Games participants. This study used a self-report questionnaire to…

  11. Senior Year Inviting More Math Choices

    Science.gov (United States)

    Cavanagh, Sean

    2008-01-01

    When students at Prescott High School sign up to take math as seniors, not all of them will be wading into precalculus or calculus, with in-depth explorations of derivatives and trigonometric functions. Some will instead end up using mathematics to study the Electoral College, or the security of Internet passwords, or how delivery companies ship…

  12. Integrative Virology for Senior Medical Students.

    Science.gov (United States)

    Koment, Roger W.

    1991-01-01

    The article describes a senior elective in virology developed at the University of South Dakota School of Medicine. Students work independently through a series of course units, selecting 12 study topics from a catalog of 35 topics in medical virology and discussing their reading daily with the professor. (DB)

  13. Integrative Virology for Senior Medical Students.

    Science.gov (United States)

    Koment, Roger W.

    1991-01-01

    The article describes a senior elective in virology developed at the University of South Dakota School of Medicine. Students work independently through a series of course units, selecting 12 study topics from a catalog of 35 topics in medical virology and discussing their reading daily with the professor. (DB)

  14. Politicization of Senior Civil Servants in Slovenia

    Directory of Open Access Journals (Sweden)

    Lea NAHTIGAL

    2013-06-01

    Full Text Available In the context of the civil service system reform, the new normative framework adopted in 2002 introduced a new management arrangement in public administration, whose consequence was the transition of senior positions within ministries, bodies within ministries, and government offices from political officials to positional civil servants with a limited term of office, who have thus become the most senior civil servants, called administrative managers. Based on extensive empirical research and statistical data, this article provides an in-depth analysis of the status and position of administrative managers, which is intended to serve as a test whether the apex of the Slovenian administrative system is politicized and in what form. In the so-called new democracies, politicization most often is manifested as a violation of the principles of political neutrality characteristic of a professional civil service, through personalized and biased appointments of senior civil servants and in the low degree of protection against lay-offs of civil servants on political grounds. Administrative managers thus often have to decide between political susceptibility and trustworthiness versus professionalism and professional accountability, for their tasks belong to the administrative and political realms. This poses a question about the degree of influence politicians exert on administrative managers and the rate of success with which administrative managers manage to retain their professionalism and independence, which should represent the key characteristics of a senior civil servant.

  15. Silver gaming : Serious fun for seniors?

    NARCIS (Netherlands)

    Loos, Eugène; Zonneveld, Annemiek

    2016-01-01

    This exploratory qualitative study provides insight into the role that exergames play for seniors. 15 participants (aged 53–78) engaged in playing Your Shape Fitness Evolved 2 on the Xbox 360 Kinect, after which we conducted a semi-structured interview with each participant. We found that in all cas

  16. The Fun Culture in Seniors' Online Communities

    Science.gov (United States)

    Nimrod, Galit

    2011-01-01

    Purpose of the study: Previous research found that "fun on line" is the most dominant content in seniors' online communities. The present study aimed to further explore the "fun culture" in these communities and to discover its unique qualities. Design and Methods: The study applied an online ethnography (netnography) approach, utilizing a full…

  17. Silver gaming : Serious fun for seniors?

    NARCIS (Netherlands)

    Loos, Eugène|info:eu-repo/dai/nl/078758475; Zonneveld, Annemiek

    2016-01-01

    This exploratory qualitative study provides insight into the role that exergames play for seniors. 15 participants (aged 53–78) engaged in playing Your Shape Fitness Evolved 2 on the Xbox 360 Kinect, after which we conducted a semi-structured interview with each participant. We found that in all cas

  18. Senior Officer Talent Management: Fostering Institutional Adaptability

    Science.gov (United States)

    2014-02-01

    impressionist art he produced in his 60s2 or “Colonel” Harlan Sanders, the failed insurance salesman who began the Kentucky Fried Chicken (KFC...and others have argued, why does the 156 Army not provide it? Perhaps it is the classic “ chicken and egg” conundrum—providing senior officers with

  19. A Senior Teacher's Implementation of Technology Integration

    Science.gov (United States)

    Tsai, Hsien-Chang

    2015-01-01

    This study investigated whether a senior teacher with many years of teaching experience, despite lacking adequate technology skills or contending with other barriers, can sufficiently implement technology integration in the classroom. The research was conducted between October 2013 and January 2014 and was focused on a junior high school biology…

  20. Students' anxiety in a senior thesis course.

    Science.gov (United States)

    Wood, M R; Palm, L J

    2000-06-01

    The State-Trait Anxiety Inventory was administered on Weeks 8, 12, and 15 of a semester to 16 students enrolled in a senior thesis course. State anxiety scores were elevated when oral presentations began and declined following the presentations. Trait anxiety scores remained constant across test administrations. The influence of situational variables on students' anxiety was discussed.

  1. KLM senior managers forgo controversial bonuses

    NARCIS (Netherlands)

    Grünell, M.

    2004-01-01

    In April 2004, the members of the management board of KLM waived bonuses offered to them in the run-up to the Dutch airline's merger with Air France, under pressure from trade unions and the government. During the current agreed national wage freeze, increases in senior management remuneration are

  2. Senior Faculty Perceptions of Social Work Journals.

    Science.gov (United States)

    Cnaan, Ram A.; And Others

    1994-01-01

    A survey of 421 senior faculty in graduate social work education investigated the familiarity and perceived quality of 120 professional journals in the field. Resulting ratings are presented for use by faculty seeking to publish their work in appropriate journals and those assessing the scholarly contribution of social work educators. (Author/MSE)

  3. Hiring Seniors: Everybody Gives, Everybody Benefits

    Science.gov (United States)

    Ruder, Robert

    2011-01-01

    Living on fixed incomes and faced with increasing taxes, senior citizens frequently feel the squeeze of a tightening economy more than other populations. Their retirement dollars buy less as their property taxes inch upward, despite the fact that they don't have school-age children. The Hempfield and Manheim Township School Districts in…

  4. Functional Heterogeneity and Senior Management Team Effectiveness

    Science.gov (United States)

    Benoliel, Pascale; Somech, Anit

    2016-01-01

    Purpose: There has been an increasing trend toward the creation of senior management teams (SMTs) which are characterized by a high degree of functional heterogeneity. Although such teams may create better linkages to information, along with the benefits of functional heterogeneity comes the potential for conflicts that stem from the value…

  5. Seniors' Online Communities: A Quantitative Content Analysis

    Science.gov (United States)

    Nimrod, Galit

    2010-01-01

    Purpose: To examine the contents and characteristics of seniors' online communities and to explore their potential benefits to older adults. Design and Methods: Quantitative content analysis of a full year's data from 14 leading online communities using a novel computerized system. The overall database included 686,283 messages. Results: There was…

  6. [Stiff person syndrome--case report].

    Science.gov (United States)

    Tomczykiewicz, Kazimierz; Pastuszak, Zanna; Staszewski, Jacek; Stepień, Adam

    2014-01-01

    Stiff person syndrome (SPS) is the rare disease and cause great inefficient. It is characterized by progressive stiffness muscles of trunk and the limbs on which the cramps of muscles overlap. In the electrophysiological investigation of the patients the involuntary discharge of motor unit potentials find and also simultaneous contraction agonistic and antagonistic muscles. SPS is presented with insulin-dependent diabetes mellitus often or is the symptom of the paraneoplastic syndrome. It is commonly associated with high anti-glutamic acid decarboxylaze (GAD) antibody titters in the serum of the blood of patients. Establishing the diagnosis can cause difficulties. We observed the patient in the last period about the atypical course the disease. The diagnosis was confirmed occurrences of the high titters of antibodies anti-GAD, the discharge of motor unit potential in paraspinal muscles in the rest and good response the treatment with diazepamem.

  7. The Stress and Stiffness Analysis of Diaphragm

    Directory of Open Access Journals (Sweden)

    Qu Dongyue

    2017-01-01

    Full Text Available Diaphragm coupling with its simple structure, small size, high reliability, which can compensate for its input and output displacement deviation by its elastic deformation, is widely used in aerospace, marine, and chemical etc. This paper uses the ANSYS software and its APDL language to analysis the stress distribution when the diaphragm under the load of torque, axial deviation, centrifugal force, angular deviation and multiple loads. We find that the value of maximum stress usually appears in the outer or inner transition region and the axial deviation has a greater influence to the distribution of the stress. Based on above, we got three kinds of stiffness for axial, angular and torque, which the stiffness of diaphragm is nearly invariable. The results can be regard as an important reference for design and optimization of diaphragm coupling.

  8. Electron profile stiffness and critical gradient studies

    Science.gov (United States)

    DeBoo, J. C.; Petty, C. C.; White, A. E.; Burrell, K. H.; Doyle, E. J.; Hillesheim, J. C.; Holland, C.; McKee, G. R.; Rhodes, T. L.; Schmitz, L.; Smith, S. P.; Wang, G.; Zeng, L.

    2012-08-01

    Electron profile stiffness was studied in DIII-D L-mode discharges by systematically varying the heat flux in a narrow region with electron cyclotron heating and measuring the local change produced in ∇Te. Electron stiffness was found to slowly increase with toroidal rotation velocity. A critical inverse temperature gradient scale length 1/LC ˜ 3 m-1 was identified at ρ =0.6 and found to be independent of rotation. Both the heat pulse diffusivity and the power balance diffusivity, the latter determined by integrating the measured dependence of the heat pulse diffusivity on -∇Te, were fit reasonably well by a model containing a critical inverse temperature gradient scale length and varying linearly with 1/LT above the threshold.

  9. The stiffness change and the increase in the ultimate capacity for a stiff pile resulting from a cyclic loading

    DEFF Research Database (Denmark)

    Lada, Aleksandra; Ibsen, Lars Bo; Nicolai, Giulio

    In the paper the experimental results of small-scale tests on a stiff monopile are presented to outline the change in stiffness during the cyclic loading and the change in the ultimate pile capacity. The results confirm the increase of stiffness and the increase in bearing capacity resulting from...... cyclic loading. Performed analysis provides a better understanding of the problem and reveals some correlations that can be useful in the future design of stiff monopiles....

  10. Efficient Method for Calculating the Composite Stiffness of Parabolic Leaf Springs with Variable Stiffness for Vehicle Rear Suspension

    OpenAIRE

    Wen-ku Shi; Cheng Liu; Zhi-yong Chen; Wei He; Qing-hua Zu

    2016-01-01

    The composite stiffness of parabolic leaf springs with variable stiffness is difficult to calculate using traditional integral equations. Numerical integration or FEA may be used but will require computer-aided software and long calculation times. An efficient method for calculating the composite stiffness of parabolic leaf springs with variable stiffness is developed and evaluated to reduce the complexity of calculation and shorten the calculation time. A simplified model for double-leaf spr...

  11. 75 FR 65673 - Appointments to Performance Review Board for Senior Executive Service

    Science.gov (United States)

    2010-10-26

    ... performance appraisal ratings and performance awards for Senior Executives and Senior Level System employees... COMMISSION Appointments to Performance Review Board for Senior Executive Service AGENCY: U.S. Nuclear Regulatory Commission. ] ACTION: Appointments to Performance Review Board for Senior Executive...

  12. Stiff modes in spinvalve simulations with OOMMF

    Energy Technology Data Exchange (ETDEWEB)

    Mitropoulos, Spyridon [Department of Computer and Informatics Engineering, TEI of Eastern Macedonia and Thrace, Kavala (Greece); Tsiantos, Vassilis, E-mail: tsianto@teikav.edu.gr [Department of Electrical Engineering, TEI of Eastern Macedonia and Thrace, Kavala, 65404 Greece (Greece); Ovaliadis, Kyriakos [Department of Electrical Engineering, TEI of Eastern Macedonia and Thrace, Kavala, 65404 Greece (Greece); Kechrakos, Dimitris [Department of Education, ASPETE, Heraklion, Athens (Greece); Donahue, Michael [Applied and Computational Mathematics Division, NIST, Gaithersburg, MD (United States)

    2016-04-01

    Micromagnetic simulations are an important tool for the investigation of magnetic materials. Micromagnetic software uses various techniques to solve differential equations, partial or ordinary, involved in the dynamic simulations. Euler, Runge-Kutta, Adams, and BDF (Backward Differentiation Formulae) are some of the methods used for this purpose. In this paper, spinvalve simulations are investigated. Evidence is presented showing that these systems have stiff modes, and that implicit methods such as BDF are more effective than explicit methods in such cases.

  13. Developing Senior Leaders’ Family and Social Strength in the Operational Army

    Science.gov (United States)

    2013-04-01

    April 2007): 87. 19 Joe Doty & Jeff Fenlason, “ Narcissism and Toxic Leaders,” Military Review Online, (January-February 2013): 55-60. 20...Generations at Work (New York, NY: Amacom, 2010). 40Justin Menkes, “ Narcissism : The Difference Between High Achievers and Leaders,” Harvard Business

  14. Senior's lifestyle and their store choice

    Directory of Open Access Journals (Sweden)

    Lesakova Dagmar

    2014-01-01

    Full Text Available To attract and retain customers, an understanding of their motives and reasons for selecting particular food and grocery store is needed. This is of particular importance in the growing segment of seniors. The size of the senior's market demands a better understanding of the older consumer. The aim of our study is to identify psychographic characteristics of the elderly consumer, and to indicate the lifestyle groups and the relationship between these groups and retail store attributes. Differences in the motives for patronizing specific food stores are analyzed for lifestyle groups. We use the lifestyle as a segmentation variable in the diverse population of seniors for the reason, that the lifestyle of the elderly provides more valuable information than chronological age alone. This information can be used by retailers to improve marketing strategies in order to appeal to a target group of senior shoppers. Empirical research is based on a self-administrated questionnaire aimed on the identification of the lifestyle characteristics and retail store attributes of the consumers in 65+ age, used for the choice of food purchasing retail stores. Lifestyles characteristics were measured by the respondents activities, interests and opinions (AIO. The results of the research indicate that there are differences among the lifestyle groups with significant differences in attitudes towards quality of products or internal store environment. Our research demonstrates the value of psychographic information over age alone regarding the patronage factors in store selection. Our study is a part of the research project VEGA 1/0612/12 'Determinants of the size, structure and tendences in the individual consumption of seniors'.

  15. 41 CFR 60-20.4 - Seniority system.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Seniority system. 60-20.4 Section 60-20.4 Public Contracts and Property Management Other Provisions Relating to Public Contracts... DISCRIMINATION GUIDELINES § 60-20.4 Seniority system. Where they exist, seniority lines and lists must not...

  16. 42 CFR 21.27 - Eligibility; senior assistant grade.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Eligibility; senior assistant grade. 21.27 Section... COMMISSIONED OFFICERS Appointment § 21.27 Eligibility; senior assistant grade. Every candidate for examination for appointment in the grade of senior assistant shall meet the requirements for eligibility for...

  17. 5 CFR 319.102 - Senior-level positions.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Senior-level positions. 319.102 Section 319.102 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS EMPLOYMENT IN SENIOR-LEVEL AND SCIENTIFIC AND PROFESSIONAL POSITIONS General § 319.102 Senior-level...

  18. 76 FR 46896 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2011-08-03

    ...: Title 5 U.S.C. 4314 requires that each agency implement a performance appraisal system making senior... evaluate the initial appraisal of a senior executive's performance by the supervisor and to make... Surface Transportation Board Senior Executive Service Performance Review Board AGENCY:...

  19. Negative Returns to Seniority: New Evidence in Academic Markets.

    Science.gov (United States)

    Bratsberg, Bernt; Ragan, James F., Jr.; Warren, John T.

    2003-01-01

    Analysis of a 21-year panel of data on economics professors found only some of the negative relationship between seniority and pay was attributable to low research productivity. Accounting for the quality of the faculty/institution match reduced the inflated estimated returns to seniority. The penalty for 20 years of seniority was 16% of salary.…

  20. 5 CFR 451.302 - Ranks for senior career employees.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Ranks for senior career employees. 451... AWARDS Presidential Rank Awards § 451.302 Ranks for senior career employees. (a) The circumstances under... Professional to a senior career employee are set forth in 5 U.S.C. 4507a. (b) To be eligible for a rank...

  1. Senior Surfing: Computer Use, Aging, and Formal Training

    Science.gov (United States)

    Warren-Peace, Paula; Parrish, Elaine; Peace, C. Brian; Xu, Jianzhong

    2008-01-01

    In this article, we describe data from two case studies of seniors (one younger senior and one older senior) in learning to use computers. The study combined interviews, observations, and documents to take a close look at their experiences with computers, as well as the influences of aging and computer training on their experiences. The study…

  2. MIGRAINE, CAROTID STIFFNESS AND GENETIC POLYMORPHISM.

    Science.gov (United States)

    Kes, Vanja Basić; Jurasić, Miljenka-Jelena; Zavoreo, Iris; Corić, Lejla; Rotim, Kresimir

    2015-12-01

    Recently migraine has been associated with increased arterial stiffness, procoagulant state, increased incidence of cerebral white matter lesions (WML) and stroke. Our aim was to compare the characteristics of migraineurs to headache free controls regarding their functional carotid ultrasound parameters. Sixty patients (45 women) with migraine (mean age 40.42 ± 10.61 years) were compared with 45 controls (30 women) with no prior history of repeating headache (mean age 38.94 ± 5.46 years) using E-tracking software on Alpha 10 ultrasound platform. Student's t-test was used on statistical analysis with alpha < 0.05. All tested carotid vascular parameters were worse in patients with migraine including increased intima-media thickness, greater carotid diameter and carotid diameter change, as well as several arterial stiffness indices. Additionally, patients with migraine had greater incidence of homozygous mutations for procoagulant genes (MTHFR (C677T), PAI-1 and ACE I/D) than expected. Computed tomography and magnetic resonance imaging of the brain showed WML in 11 patients, four of them migraine with aura patients. Since we established increased carotid stiffness and higher frequency of procoagulant gene mutations in migraineurs, we propose prospective ultrasound monitoring in such patients, especially those with detected WML, in order to timely commence more active and specific preventive stroke management strategies.

  3. A General Formulation for the Stiffness Matrix of Parallel Mechanisms

    CERN Document Server

    Quennouelle, Cyril

    2012-01-01

    Starting from the definition of a stiffness matrix, the authors present a new formulation of the Cartesian stiffness matrix of parallel mechanisms. The proposed formulation is more general than any other stiffness matrix found in the literature since it can take into account the stiffness of the passive joints, it can consider additional compliances in the joints or in the links and it remains valid for large displacements. Then, the validity, the conservative property, the positive definiteness and the relation with other formulations of stiffness matrices are discussed theoretically. Finally, a numerical example is given in order to illustrate the correctness of this matrix.

  4. Regional brain stiffness changes across the Alzheimer's disease spectrum.

    Science.gov (United States)

    Murphy, Matthew C; Jones, David T; Jack, Clifford R; Glaser, Kevin J; Senjem, Matthew L; Manduca, Armando; Felmlee, Joel P; Carter, Rickey E; Ehman, Richard L; Huston, John

    2016-01-01

    Magnetic resonance elastography (MRE) is an MRI-based technique to noninvasively measure tissue stiffness. Currently well established for clinical use in the liver, MRE is increasingly being investigated to measure brain stiffness as a novel biomarker of a variety of neurological diseases. The purpose of this work was to apply a recently developed MRE pipeline to measure regional brain stiffness changes in human subjects across the Alzheimer's disease (AD) spectrum, and to gain insights into the biological processes underlying those stiffness changes by correlating stiffness with existing biomarkers of AD. The results indicate that stiffness changes occur mostly in the frontal, parietal and temporal lobes, in accordance with the known topography of AD pathology. Furthermore, stiffness in those areas correlates with existing imaging biomarkers of AD including hippocampal volumes and amyloid PET. Additional analysis revealed preliminary but significant evidence that the relationship between brain stiffness and AD severity is nonlinear and non-monotonic. Given that similar relationships have been observed in functional MRI experiments, we used task-free fMRI data to test the hypothesis that brain stiffness was sensitive to structural changes associated with altered functional connectivity. The analysis revealed that brain stiffness is significantly and positively correlated with default mode network connectivity. Therefore, brain stiffness as measured by MRE has potential to provide new and essential insights into the temporal dynamics of AD, as well as the relationship between functional and structural plasticity as it relates to AD pathophysiology.

  5. Cosmology with a stiff matter era

    Science.gov (United States)

    Chavanis, Pierre-Henri

    2015-11-01

    We consider the possibility that the Universe is made of a dark fluid described by a quadratic equation of state P =K ρ2 , where ρ is the rest-mass density and K is a constant. The energy density ɛ =ρ c2+K ρ2 is the sum of two terms: a rest-mass term ρ c2 that mimics "dark matter" (P =0 ) and an internal energy term u =K ρ2=P that mimics a "stiff fluid" (P =ɛ ) in which the speed of sound is equal to the speed of light. In the early universe, the internal energy dominates and the dark fluid behaves as a stiff fluid (P ˜ɛ , ɛ ∝a-6). In the late universe, the rest-mass energy dominates and the dark fluid behaves as pressureless dark matter (P ≃0 , ɛ ∝a-3). We provide a simple analytical solution of the Friedmann equations for a universe undergoing a stiff matter era, a dark matter era, and a dark energy era due to the cosmological constant. This analytical solution generalizes the Einstein-de Sitter solution describing the dark matter era, and the Λ CDM model describing the dark matter era and the dark energy era. Historically, the possibility of a primordial stiff matter era first appeared in the cosmological model of Zel'dovich where the primordial universe is assumed to be made of a cold gas of baryons. A primordial stiff matter era also occurs in recent cosmological models where dark matter is made of relativistic self-gravitating Bose-Einstein condensates (BECs). When the internal energy of the dark fluid mimicking stiff matter is positive, the primordial universe is singular like in the standard big bang theory. It expands from an initial state with a vanishing scale factor and an infinite density. We consider the possibility that the internal energy of the dark fluid is negative (while, of course, its total energy density is positive), so that it mimics anti-stiff matter. This happens, for example, when the BECs have an attractive self-interaction with a negative scattering length. In that case, the primordial universe is nonsingular and

  6. On prestress stiffness analysis of bolt-plate contact assemblies

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Pedersen, Pauli

    2008-01-01

    Bolt connections are among the most important connections used in structures. The stiffnesses of the bolt and of the connected members are the primary qualities that control the lifetime of the connection. The stiffness of the bolt can be estimated rather easily, in contrast to the member stiffness......, but with finite element (FE) and contact analysis, it is possible to find the stiffness of the member. In the case of many connections and for practical applications, it is not suitable to make a full FE analysis. The purpose of the present paper is to find simplified expressions for the stiffness of the member......, including the case when the width of the member is limited. The calculation of the stiffness is based on the FE, including the solution to the contact problem, and we express the stiffness as a function of the elastic energy in the structure, whereby the definition of the displacements related...

  7. Nanocharacterization of the negative stiffness of ferroelectric materials

    Science.gov (United States)

    Alipour Skandani, A.; Ctvrtlik, R.; Al-Haik, M.

    2014-08-01

    Phase changing materials such as ferroelectric materials could exhibit negative stiffness under certain thermomechanical environments. This negative stiffness is embodied by a deflection along the opposite direction of the applied load. So far negative stiffness materials were investigated with the specific morphology of embedded inclusions in stiff matrices then the resulting composite is studied to measure the behavior of each constituent indirectly. In this study, a modified nonisothermal nanoindentation method is developed to measure the negative stiffness of triglycine sulfate single crystal directly. This in-situ method is intended to first demonstrate the feasibility of detecting the negative stiffness via nanoindentation and nanocreep of a ferroelectric material at its Curie point and then to quantify the negative stiffness without the need for embedding the crystal within a stiffer matrix.

  8. Cascades in multiplex financial networks with debts of different seniority

    Science.gov (United States)

    Brummitt, Charles D.; Kobayashi, Teruyoshi

    2015-06-01

    The seniority of debt, which determines the order in which a bankrupt institution repays its debts, is an important and sometimes contentious feature of financial crises, yet its impact on systemwide stability is not well understood. We capture seniority of debt in a multiplex network, a graph of nodes connected by multiple types of edges. Here an edge between banks denotes a debt contract of a certain level of seniority. Next we study cascading default. There exist multiple kinds of bankruptcy, indexed by the highest level of seniority at which a bank cannot repay all its debts. Self-interested banks would prefer that all their loans be made at the most senior level. However, mixing debts of different seniority levels makes the system more stable in that it shrinks the set of network densities for which bankruptcies spread widely. We compute the optimal ratio of senior to junior debts, which we call the optimal seniority ratio, for two uncorrelated Erdős-Rényi networks. If institutions erode their buffer against insolvency, then this optimal seniority ratio rises; in other words, if default thresholds fall, then more loans should be senior. We generalize the analytical results to arbitrarily many levels of seniority and to heavy-tailed degree distributions.

  9. Designing a Facebook Interface for Senior Users

    Directory of Open Access Journals (Sweden)

    Gonçalo Gomes

    2014-01-01

    Full Text Available The adoption of social networks by older adults has increased in recent years. However, many still cannot make use of social networks as these are simply not adapted to them. Through a series of direct observations, interviews, and focus groups, we identified recommendations for the design of social networks targeting seniors. Based on these, we developed a prototype for tablet devices, supporting sharing and viewing Facebook content. We then conducted a user study comparing our prototype with Facebook's native mobile application. We have found that Facebook's native application does not meet senior users concerns, like privacy and family focus, while our prototype, designed in accordance with the collected recommendations, supported relevant use cases in a usable and accessible manner.

  10. Ward management: education for senior staff nurses.

    Science.gov (United States)

    Reed, Sarah

    2008-04-01

    The key professional challenges for senior staff nurses relate to managerial rather than clinical issues, but there appears to be a lack of educational preparation for the managerial roles expected of them. An educational service was developed, implemented and evaluated in a specialist paediatric unit to address senior staff nurses' concerns related to managerial aspects of their role. An organisational development model was used to negotiate a work-based learning programme that incorporated practice competencies. This was undertaken at an Agenda for Change implementation site, which enabled the Knowledge and Skills Framework (KSF) to be trialled in practice. The educational programme was evaluated positively and practice competency evaluations highlighted how the KSF dimensions provided a usable and relevant breakdown of managerial and leadership issues. The framework provided a professional development tool for staff wishing to progress their managerial knowledge and skills while under supervision.

  11. iPad For Seniors For Dummies

    CERN Document Server

    Muir, Nancy C

    2010-01-01

    The full-color guide to the exciting new iPad, written specifically with the needs of seniors in mind!. The iPad is the perfect device for the senior market, combining the Web, e-mail, photos, video, and book reading into an intuitive, portable device. Written by veteran Dummies author Nancy Muir, this fun and friendly guide shows you how to use the many features and capabilities of the iPad to make life easier! You'll learn how to use the multitouch screen to zoom in and out on Web pages and choose a font and size that makes reading comfortable so that you can get directions, plan vacations,

  12. Designing a Facebook interface for senior users.

    Science.gov (United States)

    Gomes, Gonçalo; Duarte, Carlos; Coelho, José; Matos, Eduardo

    2014-01-01

    The adoption of social networks by older adults has increased in recent years. However, many still cannot make use of social networks as these are simply not adapted to them. Through a series of direct observations, interviews, and focus groups, we identified recommendations for the design of social networks targeting seniors. Based on these, we developed a prototype for tablet devices, supporting sharing and viewing Facebook content. We then conducted a user study comparing our prototype with Facebook's native mobile application. We have found that Facebook's native application does not meet senior users concerns, like privacy and family focus, while our prototype, designed in accordance with the collected recommendations, supported relevant use cases in a usable and accessible manner.

  13. SeniorInteraktion – Innovation gennem dialog

    DEFF Research Database (Denmark)

    SeniorInteraktion er et bud på en ny strategisk tilgang til design for det gode ’ældreliv’. Kernen i dagordenen er et fokus på at designe for social interaktion, dvs. at designe for at bevare og styrke sociale relationer, at bevare eller genskabe følelsen af at blive set og høre til samt følelsen...

  14. How senior nurses can make change happen.

    Science.gov (United States)

    Evans, Clare; Wyre, Lynne

    2010-07-01

    The Health Foundation Leaders for Change scheme, which ended last year, was a structured learning programme designed to equip healthcare professionals with the skills and knowledge needed to lead sustainable projects to improve local services. In this article, two of the participants of the last cohort, consultant nurse in perioperative care at University Hospitals Bristol NHS Foundation Trust Clare Evans and divisional senior nurse at the University Hospitals of Morecambe Bay NHS Trust Lynne Wyre, share their experiences.

  15. Nutritional evaluation of senior: a bibliographical study

    OpenAIRE

    Nara Carneiro Lacerda; Silvana Sidney Costa Santos

    2012-01-01

    The aim of this study was to research about the senior’s nutritional evaluation using bibliographical rising in the base of the bibliographical data LILACS. 24 references were found, being 11 scientific articles: 5 bibliographical and 6 of prevalence. Of the investigated material, 9 were accomplished in the Brazilian Southeast. As for the nutritional evaluation it was verified that the seniors have presented larger overweight prevalence and obesity, most of them were of women. It was noticed ...

  16. Regional Senior Tourism Marketing Strategy Research

    OpenAIRE

    Qi Zhang; Lu Cui

    2013-01-01

    In this study, we have a research of the regional senior tourism marketing strategy. The father of modern marketing p.m. Philip once pointed out: The phenomenon of people seems very fierce market competition, hides a deeper phenomenon that is service competition is the nature of competition in the market, excellent service, not to mention the excellent marketing. The importance of service marketing have become increasingly prominent, want to invincible in market competition, service enterpris...

  17. Did Senior British Officers Effectively Lead Change?

    Science.gov (United States)

    2014-12-12

    must create a vision, devise a strategy, and implement it. They require buy -in from the wider Army but this support is not guaranteed. Indeed, many...investigate. However, there is a compulsion element to any change in the British Army. Orders are orders after all. How much room there is to...support for change evident throughout? Whether Senior Leaders had any power to influence change is important due to the compulsion aspect of the

  18. Thompson′s quadricepsplasty for stiff knee

    Directory of Open Access Journals (Sweden)

    Kundu Z

    2007-01-01

    Full Text Available Background : Stiffness of the knee after trauma and/or surgery for femoral fractures is one of the most common complications and is difficult to treat. Stiffness in extension is more common and can be reduced by vigorous physiotherapy. If it does not improve then quadricepsplasty is indicated. The present study was undertaken to evaluate the results of Thompsons quadricepsplasty. Materials and Methods : 22 male patients (age range 20-45 years with posttraumatic knee stiffness following distal femoral fractures underwent Thompson′s quadricepsplasty where knee flexion range was less than 45°. The index injury in these patients was treated with plaster cast (n=5, plates (n=3, intramedullary nailing (n=3 and external fixator for open fractures (n=9. Thompson′s quadricepsplasty was performed in all the patients using anterior approach, with incision extending from upper thigh to tibial tubercle. Release of rectus femoris from underlying vastus intermedius and release of intraarticular adhesions were performed. After surgery the patients needed parentral analgesia for three days and then oral analgesics for three weeks. Active assisted knee mobilization exercises were started on the first post-operative day. Continous passive motion machine was used from the same day. Supervised physiotherapy was continued in hospital for six weeks followed by intensive knee flexion and extension exercise including cycling at home for atleast another six months. Results : Out of 22 patients, 20 had excellent to good results and two patients had poor results using criteria devised by Judet. One poor result was due to peroperative fracture of patella which was then internally fixed and hence the flexion of knee could not be started immediately. There was peroperative avulsion of tibial tuberosity in another patient who finally gained less than 50° knee flexion and hence a poor result. Conclusion : Thompsons quadricepsplasty followed by a strict and rigourous

  19. Cryotherapy induces an increase in muscle stiffness.

    Science.gov (United States)

    Point, Maxime; Guilhem, Gaël; Hug, François; Nordez, Antoine; Frey, Alain; Lacourpaille, Lilian

    2017-03-06

    Although cold application (i.e., cryotherapy) may be useful to treat sports injuries and to prevent muscle damage, it is unclear whether it has adverse effects on muscle mechanical properties. This study aimed to determine the effect of air-pulsed cryotherapy on muscle stiffness estimated using ultrasound shear wave elastography. Myoelectrical activity, ankle passive torque, shear modulus (an index of stiffness) and muscle temperature of the gastrocnemius medialis were measured before, during an air-pulsed cryotherapy (-30°) treatment of 4 sets of 4 minutes with 1 min recovery in between, and during a 40-min post-cryotherapy period. Muscle temperature significantly decreased after the second set of treatment (10 min: 32.3 ± 2.5°C; P < 0.001), peaked at 29 min (27.9 ± 2.2°C; P < 0.001) and remained below baseline values at 60 minutes (29.5 ± 2.0°C; P < 0.001). Shear modulus increased by +11.5 ± 11.8% after the second set (10 min; P = 0.011), peaked at 30 min (+34.7 ± 42.6%; P < 0.001) and remained elevated until the end of the post-treatment period (+25.4 ± 17.1%; P < 0.001). These findings provide evidence that cryotherapy induces an increase in muscle stiffness. This acute change in muscle mechanical properties may lower the amount of stretch that the muscle tissue is able to sustain without subsequent injury. This should be considered when using cryotherapy in athletic practice. This article is protected by copyright. All rights reserved.

  20. Laser application on haptics: Tactile stiffness measurement

    Science.gov (United States)

    Scalise, L.; Memeo, M.; Cannella, F.; Valente, M.; Caldwell, D. G.; Tomasini, E. P.

    2012-06-01

    There is a great interest in exploring the proprieties of the sense of the touch, its detailed knowledge in fact is a key issue in the area of robotics, haptics and human-machine interaction. In this paper, the authors focus their attention on a novel measurement method for the assessment of the tactile stiffness based on a original test rig; tactile stiffness is defined as the ratio between force, exerted by the finger, and the displacement of the finger tip operated during the test. To reach this scope, the paper describes a specific experimental test-rig used for the evaluation of subject tactile sensitivity, where finger force applied during tests as well as displacement and velocity of displacement, operated by the subject under investigation, are measured. Results show that tactile stiffness is linear respect to stimuli spatial difference (which is proportional to the difficulty to detect the variation of them). In particular, it has been possible to relate the force and displacement measured during the tests. The relationship between the response of the subject to the grating, velocity and force is determined. These results permit to carry out the further experimental tests on the same subject avoiding the use of a load cell and therefore simplifying the measurement test rig and data post-processing. Indeed, the first aspect (use of a load cell) can be relevant, because the grating positions are different, requiring a specific re-calibration and setting before each trial; while the second aspect allows simplify the test rig complexity and the processing algorithm.

  1. Three-dimensional stiffness of the carpal arch.

    Science.gov (United States)

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-01

    The carpal arch of the wrist is formed by irregularly shaped carpal bones interconnected by numerous ligaments, resulting in complex structural mechanics. The purpose of this study was to determine the three-dimensional stiffness characteristics of the carpal arch using displacement perturbations. It was hypothesized that the carpal arch would exhibit an anisotropic stiffness behavior with principal directions that are oblique to the conventional anatomical axes. Eight (n=8) cadavers were used in this study. For each specimen, the hamate was fixed to a custom stationary apparatus. An instrumented robot arm applied three-dimensional displacement perturbations to the ridge of trapezium and corresponding reaction forces were collected. The displacement-force data were used to determine a three-dimensional stiffness matrix using least squares fitting. Eigendecomposition of the stiffness matrix was used to identify the magnitudes and directions of the principal stiffness components. The carpal arch structure exhibited anisotropic stiffness behaviors with a maximum principal stiffness of 16.4±4.6N/mm that was significantly larger than the other principal components of 3.1±0.9 and 2.6±0.5N/mm (pcarpal tunnel which is accounted for by the stiff transverse ligaments that tightly bind distal carpal arch. The minimal principal stiffness is attributed to the less constraining articulation between the trapezium and scaphoid. This study provides advanced characterization of the wrist׳s three-dimensional structural stiffness for improved insight into wrist biomechanics, stability, and function.

  2. Seniority zero pair coupled cluster doubles theory.

    Science.gov (United States)

    Stein, Tamar; Henderson, Thomas M; Scuseria, Gustavo E

    2014-06-07

    Coupled cluster theory with single and double excitations accurately describes weak electron correlation but is known to fail in cases of strong static correlation. Fascinatingly, however, pair coupled cluster doubles (p-CCD), a simplified version of the theory limited to pair excitations that preserve the seniority of the reference determinant (i.e., the number of unpaired electrons), has mean field computational cost and is an excellent approximation to the full configuration interaction (FCI) of the paired space provided that the orbital basis defining the pairing scheme is adequately optimized. In previous work, we have shown that optimization of the pairing scheme in the seniority zero FCI leads to a very accurate description of static correlation. The same conclusion extends to p-CCD if the orbitals are optimized to make the p-CCD energy stationary. We here demonstrate these results with numerous examples. We also explore the contributions of different seniority sectors to the coupled cluster doubles (CCD) correlation energy using different orbital bases. We consider both Hartree-Fock and Brueckner orbitals, and the role of orbital localization. We show how one can pair the orbitals so that the role of the Brueckner orbitals at the CCD level is retained at the p-CCD level. Moreover, we explore ways of extending CCD to accurately describe strongly correlated systems.

  3. Síndrome stiff skin: relato de caso Stiff skin syndrome: case report

    Directory of Open Access Journals (Sweden)

    Adriana Gutstein da Fonseca Amorim

    2011-08-01

    Full Text Available Síndrome stiff skin é doença rara, esclerodermiforme, de etiologia desconhecida, caracterizada por endurecimento pétreo da pele, hipertricose leve e limitação da mobilidade articular. Não há tratamento efetivo até o momento. Exercícios e reabilitação são importantes para manter a qualidade de vida do paciente. Os autores apresentam caso de um menino de dois anos de idade com endurecimento cutâneo progressivo desde os oito meses de idade e restrição secundária da mobilidade articular, diagnosticado como Síndrome stiff skinStiff skin syndrome is a rare scleroderma-like disorder of unknown etiology characterized by stone-hard indurations of skin, mild hypertrichosis and limited joint mobility. No effective treatment has yet been found. Exercises and rehabilitative therapy are important in maintaining the patient's quality of life. The authors present a case of a two-year-old boy with progressive skin hardening since he was eightmonth old and secondary restricted joint mobility, diagnosed as Stiff skin syndrome

  4. Multifunctional Stiff Carbon Foam Derived from Bread.

    Science.gov (United States)

    Yuan, Ye; Ding, Yujie; Wang, Chunhui; Xu, Fan; Lin, Zaishan; Qin, Yuyang; Li, Ying; Yang, Minglong; He, Xiaodong; Peng, Qingyu; Li, Yibin

    2016-07-06

    The creation of stiff yet multifunctional three-dimensional porous carbon architecture at very low cost is still challenging. In this work, lightweight and stiff carbon foam (CF) with adjustable pore structure was prepared by using flour as the basic element via a simple fermentation and carbonization process. The compressive strength of CF exhibits a high value of 3.6 MPa whereas its density is 0.29 g/cm(3) (compressive modulus can be 121 MPa). The electromagnetic interference (EMI) shielding effectiveness measurements (specific EMI shielding effectiveness can be 78.18 dB·cm(3)·g(-1)) indicate that CF can be used as lightweight, effective shielding material. Unlike ordinary foam structure materials, the low thermal conductivity (lowest is 0.06 W/m·K) with high resistance to fire makes CF a good candidate for commercial thermal insulation material. These results demonstrate a promising method to fabricate an economical, robust carbon material for applications in industry as well as topics regarding environmental protection and improvement of energy efficiency.

  5. Elastic metamaterial beam with remotely tunable stiffness

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Wei [University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Yu, Zhengyue [School of Naval Architecture, Ocean & Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Xiaole [School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Lai, Yun [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Yellen, Benjamin B., E-mail: yellen@duke.edu [University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Mechanical Engineering and Materials Science, Duke University, P.O. Box 90300, Hudson Hall, Durham, North Carolina 27708 (United States)

    2016-02-07

    We demonstrate a dynamically tunable elastic metamaterial, which employs remote magnetic force to adjust its vibration absorption properties. The 1D metamaterial is constructed from a flat aluminum beam milled with a linear array of cylindrical holes. The beam is backed by a thin elastic membrane, on which thin disk-shaped permanent magnets are mounted. When excited by a shaker, the beam motion is tracked by a Laser Doppler Vibrometer, which conducts point by point scanning of the vibrating element. Elastic waves are unable to propagate through the beam when the driving frequency excites the first elastic bending mode in the unit cell. At these frequencies, the effective mass density of the unit cell becomes negative, which induces an exponentially decaying evanescent wave. Due to the non-linear elastic properties of the membrane, the effective stiffness of the unit cell can be tuned with an external magnetic force from nearby solenoids. Measurements of the linear and cubic static stiffness terms of the membrane are in excellent agreement with experimental measurements of the bandgap shift as a function of the applied force. In this implementation, bandgap shifts by as much as 40% can be achieved with ∼30 mN of applied magnetic force. This structure has potential for extension in 2D and 3D, providing a general approach for building dynamically tunable elastic metamaterials for applications in lensing and guiding elastic waves.

  6. Elastic metamaterial beam with remotely tunable stiffness

    Science.gov (United States)

    Qian, Wei; Yu, Zhengyue; Wang, Xiaole; Lai, Yun; Yellen, Benjamin B.

    2016-02-01

    We demonstrate a dynamically tunable elastic metamaterial, which employs remote magnetic force to adjust its vibration absorption properties. The 1D metamaterial is constructed from a flat aluminum beam milled with a linear array of cylindrical holes. The beam is backed by a thin elastic membrane, on which thin disk-shaped permanent magnets are mounted. When excited by a shaker, the beam motion is tracked by a Laser Doppler Vibrometer, which conducts point by point scanning of the vibrating element. Elastic waves are unable to propagate through the beam when the driving frequency excites the first elastic bending mode in the unit cell. At these frequencies, the effective mass density of the unit cell becomes negative, which induces an exponentially decaying evanescent wave. Due to the non-linear elastic properties of the membrane, the effective stiffness of the unit cell can be tuned with an external magnetic force from nearby solenoids. Measurements of the linear and cubic static stiffness terms of the membrane are in excellent agreement with experimental measurements of the bandgap shift as a function of the applied force. In this implementation, bandgap shifts by as much as 40% can be achieved with ˜30 mN of applied magnetic force. This structure has potential for extension in 2D and 3D, providing a general approach for building dynamically tunable elastic metamaterials for applications in lensing and guiding elastic waves.

  7. Performance of Variable Negative Stiffness MRE Vibration Isolation System

    Directory of Open Access Journals (Sweden)

    Run-pu Li

    2015-01-01

    Full Text Available Magnetorheological elastomer (MRE vibration isolation devices can improve a system’s vibration response via adjustable stiffness and damping under different magnetic fields. Combined with negative stiffness design, these MRE devices can reduce a system’s stiffness and improve the vibration control effect significantly. This paper develops a variable negative stiffness MRE isolation device by combining an improved separable iron core with laminated MREs. The relationship between the negative stiffness and the performance of the device is obtained by mathematical transformation. Its vibration response under simple harmonic excitation at small amplitude and the impact of the volume fraction of soft magnetic particles on the isolation system are also analyzed. The results show that the negative stiffness produced by the magnetic force is a major factor affecting the capacity of the isolation system. Compared to devices of the same size, the isolation system equipped with low-particle volume fraction MREs demonstrates better performance.

  8. Dynamic Vibration Absorber with Negative Stiffness for Rotor System

    Directory of Open Access Journals (Sweden)

    Hongliang Yao

    2016-01-01

    Full Text Available To suppress the vibration of a rotor system, a vibration absorber combining negative stiffness with positive stiffness together is proposed in this paper. Firstly, the negative stiffness producing mechanism using ring type permanent magnets is presented and the characteristics of the negative stiffness are analyzed. Then, the structure of the absorber is proposed; the principles and nonlinear dynamic characteristics of the absorber-rotor system are studied numerically. Finally, experiments are carried out to verify the numerical conclusions. The results show that the proposed vibration absorber is effective to suppress the vibration of the rotor system, the nonlinearity of the negatives stiffness affects the vibration suppression effect little, and the negative stiffness can broaden the effective vibration control frequency range of the absorber.

  9. ARTERIAL STIFFNESS AND CHRONIC KIDNEY DISEASE: CAUSES AND CONSEQUENCES

    Directory of Open Access Journals (Sweden)

    J. D. Kobalava

    2015-09-01

    Full Text Available Chronic kidney disease (CKD is associated with increased cardiovascular risk. CKD is characterized by accelerated aging of vessels in which the age-related arterial stiffness increase is exacerbated by a number of uremia-related processes. Increased arterial stiffness is associated with structural and functional disorders, as well as with the increase in cardiovascular mortality in patients with CKD. Increased arterial stiffness is diagnosed at an early stage of CKD. Modern understanding of the mechanisms of increased risk of cardiovascular complications in CKD, the factors contributing to the loss of elasticity of the arteries, arterial stiffness increase consequences are analyzed. Data illustrating the twoway interaction between CKD and arterial stiffness and mechanisms of accelerated progression of arterial stiffness in CKD are presented.

  10. Stiffness Evolution in Frozen Sands Subjected to Stress Changes

    KAUST Repository

    Dai, Sheng

    2017-04-21

    Sampling affects all soils, including frozen soils and hydrate-bearing sediments. The authors monitor the stiffness evolution of frozen sands subjected to various temperature and stress conditions using an oedometer cell instrumented with P-wave transducers. Experimental results show the stress-dependent stiffness of freshly remolded sands, the dominant stiffening effect of ice, creep after unloading, and the associated exponential decrease in stiffness with time. The characteristic time for stiffness loss during creep is of the order of tens of minutes; therefore it is inevitable that frozen soils experience sampling disturbances attributable to unloading. Slow unloading minimizes stiffness loss; conversely, fast unloading causes a pronounced reduction in stiffness probably attributable to the brittle failure of ice or ice-mineral bonding.

  11. Cartesian stiffness matrix of manipulators with passive joints: analytical approach

    CERN Document Server

    Pashkevich, Anatoly; Caro, Stéphane; Chablat, Damien

    2011-01-01

    The paper focuses on stiffness matrix computation for manipulators with passive joints. It proposes both explicit analytical expressions and an efficient recursive procedure that are applicable in general case and allow obtaining the desired matrix either in analytical or numerical form. Advantages of the developed technique and its ability to produce both singular and non-singular stiffness matrices are illustrated by application examples that deal with stiffness modeling of two Stewart-Gough platforms.

  12. Properties of the grasp stiffness matrix and conservative control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Kao, I.; Ngo, C. [State Univ. of New York, Stony Brook, NY (United States)

    1999-02-01

    In this paper, the authors present fundamental properties of stiffness matrices as applied in analysis of grasping and dexterous manipulation in configuration spaces and linear Euclidean R{sup 3x3} space without rotational components. A conservative-stiffness matrix in such spaces needs to satisfy both symmetric and exact differential criteria. Two types of stiffness matrices are discussed: constant and configuration-dependent matrices are discussed: constant and configuration-dependent matrices. The symmetric part of a constant-stiffness matrix can be derived from a conservative quadratic potential function in the Hermitian form; while the skew-symmetric part is a function of the nonconservative curl vector field of the grasp. A configuration-dependent stiffness matrix needs to be symmetric and must simultaneously satisfy the exact differential condition to be conservative. The theory is most relevant to the Cartesian stiffness control, where the stiffness of the end effector is usually constant, such as that in RCC wrists. Conservative control strategies are proposed for a configuration-dependent stiffness matrix. One of the most important results of this paper is the nonconservative congruence mapping of stiffness between the joint and Cartesian spaces. In general, the congruence transformation (or its inverse transformation), K{sub {theta}} = J{sub {theta}}{sup T}K{sub p}J{sub {theta}}, is a nonconservative mapping over finite paths for a configuration-dependent Jacobian. Thus, to obtain a conservative system with respect to the Cartesian space, one has to either find the corresponding K{sub {theta}} at every configuration due to the constant and symmetric Cartesian stiffness matrix, or determine symmetric yet configuration-varying K{sub {theta}} at every configuration due to the constant and symmetric Cartesian stiffness matrix, or determine the symmetric yet configuration-varying K{sub {theta}} which makes the resulting configuration-dependent K{sub p

  13. Contribution of the transverse arch to foot stiffness in humans

    OpenAIRE

    Yawar, Ali; Korpas, Lucia; Lugo-Bolanos, Maria; Mandre, Shreyas; Venkadesan, Madhusudhan

    2017-01-01

    Stiffness of the human foot is central to its mechanical function, such as elastic energy storage and propulsion. Its doubly-arched structure, manifested as longitudinal and transverse arches, is thought to underlie the stiff nature. However, previous studies have focused solely on the longitudinal arch, and little is known about whether and how the transverse arch impacts the foot's stiffness. The common observation that a flexible currency bill significantly stiffens upon curling it transve...

  14. Stiffness matrix of manipulators with passive joints: computational aspects

    CERN Document Server

    Klimchik, Alexandr; Caro, Stéphane; Chablat, Damien; 10.1109/TRO.2012.2187395

    2012-01-01

    The paper focuses on stiffness matrix computation for manipulators with passive joints, compliant actuators and flexible links. It proposes both explicit analytical expressions and an efficient recursive procedure that are applicable in the general case and allow obtaining the desired matrix either in analytical or numerical form. Advantages of the developed technique and its ability to produce both singular and non-singular stiffness matrices are illustrated by application examples that deal with stiffness modeling of two Stewart-Gough platforms.

  15. Arterial stiffness, hypertension, and rational use of nebivolol

    Directory of Open Access Journals (Sweden)

    Enrico Agabiti-Rosei

    2009-05-01

    Full Text Available Enrico Agabiti-Rosei, Enzo Porteri, Damiano RizzoniClinica Medica, Department of Medical and Surgical Sciences, University of Brescia, ItalyAbstract: Arterial stiffness plays a key role in the pathophysiology of the cardiovascular system. Some indices of arterial stiffness (pulse wave velocity, augmentation index, characteristics of central blood pressure waveform may be presently calculated and evaluated in the clinical setting. Age and blood pressure are the two major clinical determinants of increased arterial stiffness, while molecular determinants of arterial stiffness are related to fibrotic components of the extracellular matrix, mainly elastin, collagen and fibronectin. Increased arterial stiffness has been consistently observed in conditions such as hypertension, dyslipidemia and diabetes. Arterial stiffness evaluated by means of carotid-femoral pulse wave velocity yielded prognostic significance beyond and above traditional risk factors. A more favorable effect of calcium channel blockers, diuretics and ACE inhibitors compared with β-blockers on indices of arterial stiffness was observed in several studies. It is conceivable that newer β-blockers with additional vasodilating properties, such as nebivolol, which has favorable effects on carbohydrate and lipid metabolism, as well as on endothelial function and on oxidative stress, may have favorable effects on arterial stiffness, compared with atenolol. In fact, in recent studies, nebivolol was demonstrated to improve artery stiffness to a greater extent than older β-blockers. Because endothelial dysfunction and increased arterial stiffness play an important role in the early atherosclerotic processes and are associated with poor outcomes and increased mortality, independently of blood pressure, the ability of nebivolol to enhance release of endothelium-derived nitric oxide, and consequently improve endothelial function and arterial stiffness, may have significant clinical

  16. Therapeutic modification of arterial stiffness: An update and comprehensive review

    OpenAIRE

    Wu, Ching-Fen; Liu, Pang-Yen; Wu, Tsung-Jui; Hung, Yuan; Yang, Shih-Ping; Lin, Gen-Min

    2015-01-01

    Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovas...

  17. Multiple anesthetics for a patient with stiff-person syndrome.

    Science.gov (United States)

    Cassavaugh, Jessica M; Oravitz, Todd M

    2016-06-01

    Stiff-person syndrome is a progressive disease of muscle rigidity and spasticity due to a deficiency in the production of γ-aminobutyric acid. Because of the rarity of the condition, little is known about effects of anesthesia on patients with stiff-person syndrome. This report describes the clinical course for a single patient with stiff-person syndrome who received general anesthesia on 3 separate occasions. Her anesthetics included use of both neuromuscular blockade and volatile agents. Unlike several previous reports regarding anesthesia and stiff-person syndrome, the postoperative period for this patient did not require prolonged intubation or result in any residual weakness.

  18. Low frequency noise reduction using stiff light composite panels

    Institute of Scientific and Technical Information of China (English)

    DENG Yongchang; LIN Weizheng

    2003-01-01

    The experiment presented in this paper is to investigate and analyze the noise reduction at low frequency using stiff light composite panels. Since these composite panels are made of lightweight and stiff materials, this actuation strategy will enable the creation of composite panels for duct noise control without using traditional heavy structural mass. The results suggest that the mass-spring resonance absorption in the case of a comparatively stiff thick panel with a thin flexible plate is more efficient with minimum weight, when subjected to low-frequency (<500 Hz). The efficiency of the panel absorber depends on the mass of the thin flexible plate and the stiffness of the panel.

  19. Tensile Stiffness Analysis on Ocean Dynamic Power Umbilical

    Institute of Scientific and Technical Information of China (English)

    汤明刚; 阎军; 王野; 岳前进

    2014-01-01

    Tensile stiffness of ocean dynamic power umbilical is an important design parameter for functional implementation and structural safety. A column with radial stiffness which is wound by helical steel wires is constructed to predict the tensile stiffness value of umbilicals in the paper. The relationship between the tension and axial deformation is expressed analytically so the radial contraction of the column is achieved in the relationship by use of a simple finite element method. With an agreement between the theoretical prediction and the tension test results, the method is proved to be simple and efficient for the estimation of tensile stiffness of the ocean dynamic power umbilical.

  20. Stiffness Analysis Of Multi-Chain Parallel Robotic Systems

    CERN Document Server

    Pashkevich, Anatoly; Chablat, Damien; Wenger, Philippe

    2009-01-01

    The paper presents a new stiffness modelling method for multi-chain parallel robotic manipulators with flexible links and compliant actuating joints. In contrast to other works, the method involves a FEA-based link stiffness evaluation and employs a new solution strategy of the kinetostatic equations, which allows computing the stiffness matrix for singular postures and to take into account influence of the external forces. The advantages of the developed technique are confirmed by application examples, which deal with stiffness analysis of a parallel manipulator of the Orthoglide family

  1. Stiffness Analysis Of Multi-Chain Parallel Robotic Systems

    CERN Document Server

    Pashkevich, Anatoly; Wenger, Philippe

    2008-01-01

    The paper presents a new stiffness modelling method for multi-chain parallel robotic manipulators with flexible links and compliant actuating joints. In contrast to other works, the method involves a FEA-based link stiffness evaluation and employs a new solution strategy of the kinetostatic equations, which allows computing the stiffness matrix for singular postures and to take into account influence of the internal forces. The advantages of the developed technique are confirmed by application examples, which deal with stiffness analysis of the Orthoglide manipulator.

  2. A novel variable stiffness mechanism for dielectric elastomer actuators

    Science.gov (United States)

    Li, Wen-Bo; Zhang, Wen-Ming; Zou, Hong-Xiang; Peng, Zhi-Ke; Meng, Guang

    2017-08-01

    In this paper, a novel variable stiffness mechanism is proposed for the design of a variable stiffness dielectric elastomer actuator (VSDEA) which combines a flexible strip with a DEA in a dielectric elastomer minimum energy structure. The DEA induces an analog tuning of the transverse curvature of the strip, thus conveniently providing a voltage-controllable flexural rigidity. The VSDEA tends to be a fully flexible and compact structure with the advantages of simplicity and fast response. Both experimental and theoretical investigations are carried out to reveal the variable stiffness performances of the VSDEA. The effect of the clamped location on the bending stiffness of the VSDEA is analyzed, and then effects of the lengths, the loading points and the applied voltages on the bending stiffness are experimentally investigated. An analytical model is developed to verify the availability of this variable stiffness mechanism, and the theoretical results demonstrate that the bending stiffness of the VSDEA decreases as the applied voltage increases, which agree well with the experimental data. Moreover, the experimental results show that the maximum change of the relative stiffness can reach about 88.80%. It can be useful for the design and optimization of active variable stiffness structures and DEAs for soft robots, vibration control, and morphing applications.

  3. Relationship of rolling bearing stiffness with diameter of roller

    Institute of Scientific and Technical Information of China (English)

    郭茂林; 王刚; 张瑞

    2002-01-01

    The theoretical formula of roller bearing stiffness is induced and compared with its empirical formula.In the experience formula the stiffness of roller bearing has nothing to do with the roller diameter. The relation-ship of roller bearing stiffness with roller diameter was studied using Hz contacting theory. It is concluded thatconclusion in experience formula is only approximate result of data processing under special conditions, and therelation between stiffness of roller bearing and roller diameter must be taken into consideration while designingor selecting roller bearings.

  4. Arterial stiffness: pathophysiology and clinical impact.

    Science.gov (United States)

    London, Gérard M; Marchais, Sylvain J; Guerin, Alain P; Pannier, Bruno

    2004-01-01

    The ill effects of hypertension are usually attributed to a reduction in the caliber or the number of arterioles, resulting in an increase in total peripheral resistance (TPR). This definition does not take into account the fact that BP is a cyclic phenomenon with systolic and diastolic BP being the limits of these oscillations. The appropriate term to define the arterial factor(s) opposing LV ejection is aortic input impedance which depends on TPR, arterial distensibility (D), and wave reflections (WR). D defines the capacitive properties of arterial stiffness, whose role is to dampen pressure and flow oscillations and to transform pulsatile flow and pressure in arteries into a steady flow and pressure in peripheral tissues. Stiffness is the reciprocal value of D. These parameters are BP dependent, and arteries become stiffer at high pressure. In to D which provides information about the elasticity> of artery as a hollow structure, the elastic incremental modulus (Einc) characterizes the properties of the arterial wall biomaterials, independently of vessel geometry. As an alternative, arterial D can be evaluated by measuring the pulse wave velocity (PWV) which increases with the stiffening of arteries. Arterial stiffening increases left ventricular (LV) afterload and alters the coronary perfusion. With increased PWV, the WR impacts on the aorta during systole, increasing systolic pressures and myocardial oxygen consumption, and decreasing diastolic BP and coronary flow. The arterial stiffness is altered primarily in association with increased collagen content and alterations of extracellular matrix (arteriosclerosis) as classically observed during aging or in arterial hypertension. The arterial stiffening estimated by changes in aortic PWV and intensity of WR are independent predictors of survival in end stage renal disease (ESRD) and general population. Improvement of arterial stiffening could be obtained by antihypertensive treatmen as observed with the calcium

  5. An infinitely-stiff elastic system via a tuned negative-stiffness component stabilized by rotation-produced gyroscopic forces

    Science.gov (United States)

    Kochmann, D. M.; Drugan, W. J.

    2016-06-01

    An elastic system containing a negative-stiffness element tuned to produce positive-infinite system stiffness, although statically unstable as is any such elastic system if unconstrained, is proved to be stabilized by rotation-produced gyroscopic forces at sufficiently high rotation rates. This is accomplished in possibly the simplest model of a composite structure (or solid) containing a negative-stiffness component that exhibits all these features, facilitating a conceptually and mathematically transparent, completely closed-form analysis.

  6. Maltreatment, abuse and neglect seniors from the perspective of nurse.

    OpenAIRE

    HAMPERGROVÁ, Izabela

    2016-01-01

    This thesis called "Mistreat, abuse and neglect of seniors from the point of view of a nurse" comprises of theoretical and empirical part. It deals with violence against seniors and the point of view of a nurse on this problem. The theoretical part of this thesis comprehensively summarizes the issue of physical and emotional abuse and neglect of seniors. It contains definitions and important concepts and forms of violence, which are described in detail. Very important part is also the descrip...

  7. Životní spokojenost seniorů

    OpenAIRE

    Salomonová, Renata

    2008-01-01

    The name of the Thesis: Life Satisfaction of Seniors The Goal of the Thesis: The primary goal ofthis thesis is to find out and compare the life satisfaction level amongst passive and sports-active seniors (65+). The secondary goal is to find out the depression level within the group of seniors, evaluate the geriatrie depression scale and define relations between level of depression and life satisfaction. Methods: Questionnaires in writing are used for collection of data and to identify life s...

  8. Toxoplasma gondii impairs memory in infected seniors.

    Science.gov (United States)

    Gajewski, Patrick D; Falkenstein, Michael; Hengstler, Jan G; Golka, Klaus

    2014-02-01

    Almost 30% of humans present a Toxoplasma gondii positive antibody status and its prevalence increases with age. The central nervous system is the main target. However, little is known about the influence of asymptomatic i.e. latent Toxoplasmosis on cognitive functions in humans. To investigate neurocognitive dysfunctions in asymptomatic older adults with T. gondii positive antibody status a double-blinded neuropsychological study was conducted. The participants were classified from a population-based sample (N=131) of healthy participants with an age of 65 years and older into two groups with 42 individuals each: Toxoplasmosis positive (T-pos; IgG>50 IU/ml) and Toxoplasmosis negative (T-neg; IgG=0 IU/ml). The outcome measures were a computer-based working-memory test (2-back) and several standardized psychometric tests of memory and executive cognitive functions. T-pos seniors showed an impairment of different aspects of memory. The rate of correctly detected target symbols in a 2-back task was decreased by nearly 9% (P=0.020), corresponding to a performance reduction of about 35% in working memory relative to the T-neg group. Moreover, T-pos seniors had a lower performance in a verbal memory test, both regarding immediate recall (10% reduction; P=0.022), delayed recognition (6%; P=0.037) and recall from long-term memory assessed by the word fluency tests (12%; P=0.029). In contrast, executive functions were not affected. The effects remained mostly unchanged after controlling for medication. The impairment of memory functions in T-pos seniors was accompanied by a decreased self-reported quality of life. Because of the high prevalence of asymptomatic Toxoplasmosis and an increasing population of older adults this finding is of high relevance for public health.

  9. Cellular mechanoadaptation to substrate mechanical properties: contributions of substrate stiffness and thickness to cell stiffness measurements using AFM.

    Science.gov (United States)

    Vichare, Shirish; Sen, Shamik; Inamdar, Mandar M

    2014-02-28

    Mechanosensing by adherent cells is usually studied by quantifying cell responses on hydrogels that are covalently linked to a rigid substrate. Atomic force microscopy (AFM) represents a convenient way of characterizing the mechanoadaptation response of adherent cells on hydrogels of varying stiffness and thickness. Since AFM measurements reflect the effective cell stiffness, therefore, in addition to measuring real cytoskeletal alterations across different conditions, these measurements might also be influenced by the geometry and physical properties of the substrate itself. To better understand how the physical attributes of the gel influence AFM stiffness measurements of cells, we have used finite element analysis to simulate the indentation of cells of various spreads resting on hydrogels of varying stiffness and thickness. Consistent with experimental results, our simulation results indicate that for well spread cells, stiffness values are significantly over-estimated when experiments are performed on cells cultured on soft and thin gels. Using parametric studies, we have developed scaling relationships between the effective stiffness probed by AFM and the bulk cell stiffness, taking cell and tip geometry, hydrogel properties, nuclear stiffness and cell contractility into account. Finally, using simulated mechanoadaptation responses, we have demonstrated that a cell stiffening response may arise purely due to the substrate properties. Collectively, our results demonstrate the need to take hydrogel properties into account while estimating cell stiffness using AFM indentation.

  10. Facebook & Twitter for seniors for dummies

    CERN Document Server

    Collier, Marsha

    2014-01-01

    New to social media? This easy-to-use guide will get you started in no time! Social media is a ton of fun, and this updated guide makes it easy to set up a Facebook or Twitter account to catch up with old friends, communicate with your family, and enjoy your online experience. You'll get hands-on guidance to connecting to the Internet with a computer or mobile device, creating social media accounts and profiles, searching for friends, joining groups, sharing photos and videos, and more. If you're one of the 100+ million seniors using Facebook or other social media sites, this 2nd Edition of Fa

  11. [Silver gaming: serious fun for seniors?].

    Science.gov (United States)

    Zonneveld, Annemiek; Loos, Eugene F

    2015-06-01

    This exploratory qualitative study provides insight into the role that exergames can play for seniors. Fifteen participants (aged 53-78) engaged in playing Your Shape Fitness Evolved 2 on the Xbox 360 Kinect. We conducted semi-structured interviews with each participant and we found that in all cases, their innate psychological needs of autonomy and competence (Self Determination Theory) were met. Playing the exergame not only served as a serious therapeutic instrument with positive effects on the subjective physical and social wellbeing, but it also brought entertainment, providing excitement and fun.

  12. Discrete computational mechanics for stiff phenomena

    KAUST Repository

    Michels, Dominik L.

    2016-11-28

    Many natural phenomena which occur in the realm of visual computing and computational physics, like the dynamics of cloth, fibers, fluids, and solids as well as collision scenarios are described by stiff Hamiltonian equations of motion, i.e. differential equations whose solution spectra simultaneously contain extremely high and low frequencies. This usually impedes the development of physically accurate and at the same time efficient integration algorithms. We present a straightforward computationally oriented introduction to advanced concepts from classical mechanics. We provide an easy to understand step-by-step introduction from variational principles over the Euler-Lagrange formalism and the Legendre transformation to Hamiltonian mechanics. Based on such solid theoretical foundations, we study the underlying geometric structure of Hamiltonian systems as well as their discrete counterparts in order to develop sophisticated structure preserving integration algorithms to efficiently perform high fidelity simulations.

  13. Determining cantilever stiffness from thermal noise

    Directory of Open Access Journals (Sweden)

    Jannis Lübbe

    2013-03-01

    Full Text Available We critically discuss the extraction of intrinsic cantilever properties, namely eigenfrequency fn, quality factor Qn and specifically the stiffness kn of the nth cantilever oscillation mode from thermal noise by an analysis of the power spectral density of displacement fluctuations of the cantilever in contact with a thermal bath. The practical applicability of this approach is demonstrated for several cantilevers with eigenfrequencies ranging from 50 kHz to 2 MHz. As such an analysis requires a sophisticated spectral analysis, we introduce a new method to determine kn from a spectral analysis of the demodulated oscillation signal of the excited cantilever that can be performed in the frequency range of 10 Hz to 1 kHz regardless of the eigenfrequency of the cantilever. We demonstrate that the latter method is in particular useful for noncontact atomic force microscopy (NC-AFM where the required simple instrumentation for spectral analysis is available in most experimental systems.

  14. Vibration control via stiffness switching of magnetostrictive transducers

    Science.gov (United States)

    Scheidler, Justin J.; Asnani, Vivake M.; Dapino, Marcelo J.

    2016-04-01

    In this paper, a computational study is presented of structural vibration control that is realized by switching a magneto-strictive transducer between high and low stiffness states. Switching is accomplished by either changing the applied magnetic field with a voltage excitation or changing the shunt impedance on the transducer's coil (i.e., the magneto-strictive material's magnetic boundary condition). Switched-stiffness vibration control is simulated using a lumped mass supported by a damper and the magneto-strictive transducer (mount), which is represented by a nonlinear, electromechanical model. Free vibration of the mass is calculated while varying the mount's stiffness according to a reference switched-stiffness vibration control law. The results reveal that switching the magnetic field produces the desired change in stiffness, but also an undesired actuation force that can significantly degrade the vibration control. Hence, a modified switched-stiffness control law that accounts for the actuation force is proposed and implemented for voltage-controlled stiffness switching. The influence of the magneto-mechanical bias condition is also discussed. Voltage-controlled stiffness switching is found to introduce damping equivalent to a viscous damping factor up to about 0.13; this is shown to primarily result from active vibration reduction caused by the actuation force. The merit of magneto-strictive switched-stiffness vibration control is then quantified by comparing the results of voltage- and shunt-controlled stiffness switching to the performance of optimal magneto-strictive shunt damping. For the cases considered, optimal resistive shunt damping performed considerably better than both voltage- and shunt-controlled stiffness switching.

  15. Arterial stiffness, hypertension, and rational use of nebivolol.

    Science.gov (United States)

    Agabiti-Rosei, Enrico; Porteri, Enzo; Rizzoni, Damiano

    2009-01-01

    Arterial stiffness plays a key role in the pathophysiology of the cardiovascular system. Some indices of arterial stiffness (pulse wave velocity, augmentation index, characteristics of central blood pressure waveform) may be presently calculated and evaluated in the clinical setting. Age and blood pressure are the two major clinical determinants of increased arterial stiffness, while molecular determinants of arterial stiffness are related to fibrotic components of the extracellular matrix, mainly elastin, collagen and fibronectin. Increased arterial stiffness has been consistently observed in conditions such as hypertension, dyslipidemia and diabetes. Arterial stiffness evaluated by means of carotid-femoral pulse wave velocity yielded prognostic significance beyond and above traditional risk factors. A more favorable effect of calcium channel blockers, diuretics and ACE inhibitors compared with beta-blockers on indices of arterial stiffness was observed in several studies. It is conceivable that newer beta-blockers with additional vasodilating properties, such as nebivolol, which has favorable effects on carbohydrate and lipid metabolism, as well as on endothelial function and on oxidative stress, may have favorable effects on arterial stiffness, compared with atenolol. In fact, in recent studies, nebivolol was demonstrated to improve artery stiffness to a greater extent than older beta-blockers. Because endothelial dysfunction and increased arterial stiffness play an important role in the early atherosclerotic processes and are associated with poor outcomes and increased mortality, independently of blood pressure, the ability of nebivolol to enhance release of endothelium-derived nitric oxide, and consequently improve endothelial function and arterial stiffness, may have significant clinical implications for the use of this agent in the treatment of hypertension and cardiovascular diseases.

  16. 76 FR 20243 - Retired and Senior Volunteer Program Amendments

    Science.gov (United States)

    2011-04-12

    ... for the visually impaired. SUPPLEMENTARY INFORMATION: I. Background--The October 26, 2010, Proposed... has considerable experience in using outside reviewers with expertise in senior service and aging...

  17. Senior Aids for Senior Readers; A Visual Aids Pamphlet for the Elderly.

    Science.gov (United States)

    Houston Public Library, TX.

    A pamphlet on special aids for senior library users lists items available from the Houston Public Library. Magnifiers (some illuminated), bedspecs (prism glasses), book holders, large print telephone dials, and games suitable for the visually handicapped or bedridden are described. The library's collections of slides and films, both 8mm and 16mm,…

  18. Arthroscopic capsular release for refractory shoulder stiffness.

    Science.gov (United States)

    Fernandes, Marcos Rassi

    2013-01-01

    To evaluate the results of the arthroscopic treatment of refractory adhesive capsulitis of the shoulder with two to nine years of follow-up, comparing the pre- and postoperative range of motion. This was an observational study (case series) of 18 patients who underwent arthroscopic capsular release for refractory shoulder stiffness. The mean age was of 53.6 years (range: 39 to 68), with female predominance (77.77%) and nine cases left shoulders. There were 6 primary (33.33%) and 12 secondary cases (66.67%). Arthroscopic capsular release was performed in all patients after a mean of 9.33 months of physical therapy (range: 6 to 20 months) with a minimum follow-up of two years (range: 26 to 110 months). The mean active and passive forward flexion, external rotation and internal rotation increased from 94.4°/103.3°, 11.9°/21.9°, and S1/L5 vertebral level, respectively, to 151.1°/153.8°, 57.2°/64.4°, and T12/T10 vertebral level, respectively. There was a significant difference between the pre- and postoperative range of motion (p < 0.001). According to the Constant-Murley functional score (ROM), the value increased from 14 (preoperative mean) to 30 points (postoperative mean). Postoperatively, all patients showed diminished shoulder pain (none or mild/15 or 10 points in the Constant-Murley score). Arthroscopic treatment is an effective treatment for refractory shoulder stiffness. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  19. Clinical Study of Tuina for Stiff Neck

    Institute of Scientific and Technical Information of China (English)

    吴耀持; 张峻峰; 汪崇淼; 王健雄; 张沈煜

    2009-01-01

    Objective: To observe the clinical effect of Tuina for stiffneck. Methods: All of 216 cases with stiff neck were randomly allocated into a tuina group (110 cases) and a control group (106 cases). The patients in the tuina group were treated with "Three Parts, Four Points,Five Manipulation" tuina therapy, while those in the control group were treated with pucturing Wailaogong (Ex-UE 8), Houxi (SI 3), Jianjing (GB 21) and Ashi points in the affected side,Once a day, and 3 times constitute one treatment course. The effect was observed after 2-course treatments. Result: The effective rate in the tuina group and the control group was 93.64% and 83.02%, respectively, and there was statistical difference between the two groups (P < 0.05).Conclusion: The tuina therapy of "Three Parts, Four Points, Five Manipulations" is better than simple acupuncture therapy in treating stiff neck.%目的:观察推拿治疗落枕的临床疗效.方法:将216例落枕患者随机分为推拿组110例和对照组106例,推拿组用"三部四穴五法"推拿法治疗,对照组针刺患侧外劳宫、后溪、肩井和阿是穴.每日1次,3次为1个疗程;治疗2个疗程后观察疗效. 结果:推拿组有效率为93.64%,对照组为83.02%,两者比较有统计学意义(P<0.05)结论:"三部四穴五法"推拿法治疗落枕明显优于单纯针刺疗法.

  20. Estonia's Big Boys' Club / Justin Petrone

    Index Scriptorium Estoniae

    Petrone, Justin, 1979-

    2007-01-01

    Eesti üliõpilasseltside ajaloost, liikmetest ning mõjust Eesti ühiskonnale ja poliitikale. Lähemalt Eesti Üliõpilaste Seltsist (EÜS), selle tekkest, taastamisest Gorbatšovi reformide aastail, liikmeskonnast, suhetest teiste korporatsioonidega. EÜSi liikmete hulka kuulub ka president Toomas Hendrik Ilves. Ajakirjanumbri esikaanel T.H. Ilvese foto

  1. Justin Bieber,His Fun Music World

    Institute of Scientific and Technical Information of China (English)

    罗以宁

    2010-01-01

    贾斯汀·比伯12岁的时候,他参加了他家乡加拿大斯特佛德的歌唱比赛,并获得第二名。他想和他的家人分享这个消息,便把比赛的片段发到YouTube上。随着时间的推移,比伯上传了更多他唱歌时的视频,而他的亲戚并不是唯一去注意的人。5500多万歌迷也登录观看比伯演唱他最喜欢的艺术家的歌曲,包括亚瑟小子、尼欧和史提夫·汪达。

  2. Estonia's Big Boys' Club / Justin Petrone

    Index Scriptorium Estoniae

    Petrone, Justin, 1979-

    2007-01-01

    Eesti üliõpilasseltside ajaloost, liikmetest ning mõjust Eesti ühiskonnale ja poliitikale. Lähemalt Eesti Üliõpilaste Seltsist (EÜS), selle tekkest, taastamisest Gorbatšovi reformide aastail, liikmeskonnast, suhetest teiste korporatsioonidega. EÜSi liikmete hulka kuulub ka president Toomas Hendrik Ilves. Ajakirjanumbri esikaanel T.H. Ilvese foto

  3. A Stiffness Estimator for Agonistic-Antagonistic Variable-Stiffness-Actuator Devices

    OpenAIRE

    Menard, Tomas; Grioli, Giorgio; Bicchi, Antonio

    2014-01-01

    International audience; Safe Physical Human Robot Interaction, conservation of energy and adaptability are just the main robotic applications that prompted the development of a number of Variable Stiffness Actuators (VSA). Implemented in a variety of ways, they use various technologies, and feature the most diverse mechanical solutions, all of which share a fundamentally unavoidable nonlinear behavior. The control schemes proposed for these actuators typically aim at independent control of th...

  4. General Torsional Stiffness Matching of Off-road Vehicle

    Institute of Scientific and Technical Information of China (English)

    HUANG Song

    2009-01-01

    Increasing frame torsional stiffness of off-road vehicle will lead to the decrease of body torsional deformation, but the increase of torsional loads of flame and suspension system and the decrease of wheel adhesive weight. In severe case, a certain wheel will be out of contact with road surface. Appropriate matching of body, flame and suspension torsional stiffnesses is a difficult problem for off-road vehicle design. In this paper, these theoretically analytic models of the entire vehicle, body, frame and suspension torsional stiffness are constructed based on the geometry and mechanism of a light off-road vehicle's body, frame and suspension. The body and frame torsional stiffnesses can be calculated by applying body CAE method, meanwhile the suspension's rolling angle stiffness can be obtained by the bench test of the suspension's elastic elements. Through fixing the entire vehicle, using sole timber to raise wheels to simulate the road impact on a certain wheel, the entire vehicle torsional stiffness can be calculated on the geometric relation and loads of testing. Finally some appropriate matching principles of the body, frame and suspension torsional stiffness are summarized according to the test and analysis results. The conclusion can reveal the significance of the suspension torsional stiffness on off-road vehicle's torsion-absorbing capability. The results could serve as a reference for the design of other off-road vehicles.

  5. Mechanically stiff, electrically conductive composites of polymers and carbon nanotubes

    Science.gov (United States)

    Worsley, Marcus A.; Kucheyev, Sergei O.; Baumann, Theodore F.; Kuntz, Joshua D.; Satcher, Jr., Joe H.; Hamza, Alex V.

    2015-07-21

    Using SWNT-CA as scaffolds to fabricate stiff, highly conductive polymer (PDMS) composites. The SWNT-CA is immersing in a polymer resin to produce a SWNT-CA infiltrated with a polymer resin. The SWNT-CA infiltrated with a polymer resin is cured to produce the stiff and electrically conductive composite of carbon nanotube aerogel and polymer.

  6. Extracellular Matrix Stiffness Regulates Osteogenic Differentiation through MAPK Activation.

    Directory of Open Access Journals (Sweden)

    Jun-Ha Hwang

    Full Text Available Mesenchymal stem cell (MSC differentiation is regulated by the extracellular matrix (ECM through activation of intracellular signaling mediators. The stiffness of the ECM was shown to be an important regulatory factor for MSC differentiation, and transcriptional coactivator with PDZ-binding motif (TAZ was identified as an effector protein for MSC differentiation. However, the detailed underlying mechanism regarding the role of ECM stiffness and TAZ in MSC differentiation is not yet fully understood. In this report, we showed that ECM stiffness regulates MSC fate through ERK or JNK activation. Specifically, a stiff hydrogel matrix stimulates osteogenic differentiation concomitant with increased nuclear localization of TAZ, but inhibits adipogenic differentiation. ERK and JNK activity was significantly increased in cells cultured on a stiff hydrogel. TAZ activation was induced by ERK or JNK activation on a stiff hydrogel because exposure to an ERK or JNK inhibitor significantly decreased the nuclear localization of TAZ, indicating that ECM stiffness-induced ERK or JNK activation is important for TAZ-driven osteogenic differentiation. Taken together, these results suggest that ECM stiffness regulates MSC differentiation through ERK or JNK activation.

  7. Association of Parental Hypertension With Arterial Stiffness in Nonhypertensive Offspring

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Quiroz, Rene; Enserro, Danielle

    2016-01-01

    High arterial stiffness seems to be causally involved in the pathogenesis of hypertension. We tested the hypothesis that offspring of parents with hypertension may display higher arterial stiffness before clinically manifest hypertension, given that hypertension is a heritable condition. We compa...

  8. Alcohol intake and aortic stiffness in young men and women

    NARCIS (Netherlands)

    Elzen, A.P. van den; Sierksma, A.; Oren, A.; Vos, L.E.; Witteman, J.C.; Grobbee, D.E.; Hendriks, H.F.; Uiterwaal, C.S.; Bots, M.L.

    2005-01-01

    Background: Moderate alcohol consumption has been shown to protect against cardiovascular disease. Aortic stiffness can be regarded as a marker of cardiovascular disease risk. Previously we have shown an inverse to J-shaped association between alcohol intake and aortic stiffness in middle-aged and e

  9. Extracellular Matrix Stiffness Regulates Osteogenic Differentiation through MAPK Activation.

    Science.gov (United States)

    Hwang, Jun-Ha; Byun, Mi Ran; Kim, A Rum; Kim, Kyung Min; Cho, Hang Jun; Lee, Yo Han; Kim, Juwon; Jeong, Mi Gyeong; Hwang, Eun Sook; Hong, Jeong-Ho

    2015-01-01

    Mesenchymal stem cell (MSC) differentiation is regulated by the extracellular matrix (ECM) through activation of intracellular signaling mediators. The stiffness of the ECM was shown to be an important regulatory factor for MSC differentiation, and transcriptional coactivator with PDZ-binding motif (TAZ) was identified as an effector protein for MSC differentiation. However, the detailed underlying mechanism regarding the role of ECM stiffness and TAZ in MSC differentiation is not yet fully understood. In this report, we showed that ECM stiffness regulates MSC fate through ERK or JNK activation. Specifically, a stiff hydrogel matrix stimulates osteogenic differentiation concomitant with increased nuclear localization of TAZ, but inhibits adipogenic differentiation. ERK and JNK activity was significantly increased in cells cultured on a stiff hydrogel. TAZ activation was induced by ERK or JNK activation on a stiff hydrogel because exposure to an ERK or JNK inhibitor significantly decreased the nuclear localization of TAZ, indicating that ECM stiffness-induced ERK or JNK activation is important for TAZ-driven osteogenic differentiation. Taken together, these results suggest that ECM stiffness regulates MSC differentiation through ERK or JNK activation.

  10. A METHOD FOR STIFFNESS MATRIX OF TRIANGULAR TORUS ELEMENT

    Directory of Open Access Journals (Sweden)

    Durmuş GÜNAY

    1996-01-01

    Full Text Available The matrices of constants for the stiffness matrices of triangular torus elements family are generated on computer by using the expression given in literature. After the matrices are generated once, it is easy to obtain the stiffness matrices for all member of family of triangular torus elements without need for numerical integration.

  11. Mechanical stiffness: a global parameter associated to elite sprinters performance

    Directory of Open Access Journals (Sweden)

    Fernando López Mangini

    Full Text Available Abstract This study analyzes vertical stiffness as a global parameter that could be directly associated to sprinter's performance. We evaluated vertical stiffness, performance, heart rate and lactate concentration on fifteen male sprinters that ran on a treadmill at gait transition speed and 13 km h−1. Vertical Stiffness was determined by the ratio of the vertical acceleration peak and maximum displacement of the center of mass. Physiological parameters were measured throughout the experimental procedure and performance was estimated by athlete's time records on 100 m track race. As expected, vertical stiffness and heart rate increased with running speed. We found a high correlation between heart rate and vertical stiffness at gait transition speed. However, at 13 km h−1, lactate peak showed a higher correlation with vertical stiffness, suggesting a greater participation of the anaerobic system. An inverse relationship between performance and vertical stiffness was found, where faster athletes were the stiffer ones. Performance and lactate peak presented the same inverse relationship; faster athletes had higher lactate peaks. As a result, faster athletes were stiffer and consume more energy. All in all, these findings suggest that mechanical stiffness could be a potential global parameter to evaluate performance in sprinters.

  12. Modeling and design of energy efficient variable stiffness actuators

    NARCIS (Netherlands)

    Visser, L.C.; Carloni, Raffaella; Ünal, Ramazan; Stramigioli, Stefano

    In this paper, we provide a port-based mathematical framework for analyzing and modeling variable stiffness actuators. The framework provides important insights in the energy requirements and, therefore, it is an important tool for the design of energy efficient variable stiffness actuators. Based

  13. Reference values for local arterial stiffness. Part B : femoral artery

    NARCIS (Netherlands)

    Bossuyt, Jelle; Engelen, Lian; Ferreira, Isabel; Stehouwer, Coen D; Boutouyrie, Pierre; Laurent, Stéphane; Segers, Patrick; Reesink, Koen; Van Bortel, Luc M

    2015-01-01

    OBJECTIVE: Carotid-femoral pulse wave velocity (PWV) is considered the gold standard measure of arterial stiffness, representing mainly aortic stiffness. As compared with the elastic carotid and aorta, the more muscular femoral artery may be differently associated with cardiovascular risk factors (C

  14. Senior doctors' opinions of rational suicide.

    Science.gov (United States)

    Ginn, Stephen; Price, Annabel; Rayner, Lauren; Owen, Gareth S; Hayes, Richard D; Hotopf, Matthew; Lee, William

    2011-12-01

    The attitudes of medical professionals towards physician assisted dying have been widely discussed. Less explored is the level of agreement among physicians on the possibility of 'rational suicide'-a considered suicide act made by a sound mind and a precondition of assisted dying legislation. To assess attitudes towards rational suicide in a representative sample of senior doctors in England and Wales. A postal survey was conducted of 1000 consultants and general practitioners randomly selected from a commercially available database. The main outcome of interest was level of agreement with a statement about rational suicide. The corrected participation rate was 50%; 363 questionnaires were analysed. Overall 72% of doctors agreed with the possibility of rational suicide, 17% disagreed, and 11% were neutral. Doctors who identified themselves as being more religious were more likely to disagree. Some doctors who disagreed with legalisation of physician assisted suicide nevertheless agreed with the concept of rational suicide. Most senior doctors in England and Wales feel that rational suicide is possible. There was no association with specialty. Strong religious belief was associated with disagreement, although levels of agreement were still high in people reporting the strongest religious belief. Most doctors who were opposed to physician assisted suicide believed that rational suicide was possible, suggesting that some medical opposition is best explained by other factors such as concerns of assessment and protection of vulnerable patients.

  15. What do seniors remember from freshman physics?

    Directory of Open Access Journals (Sweden)

    Andrew Pawl

    2012-12-01

    Full Text Available We have given a group of 56 Massachusetts Institute of Technology (MIT seniors who took mechanics as freshmen a written test similar to the final exam they took in their freshman course as well as the Mechanics Baseline Test (MBT and the Colorado Learning Attitudes about Science Survey (CLASS. Students in majors unrelated to physics scored 60% lower on the written analytic part of the final than they would have as freshmen. The mean score of all participants on the MBT was insignificantly changed from their average on the posttest they took as freshmen. However, the students’ performance on 9 of the 26 MBT items (with 6 of the 9 involving graphical kinematics represents a gain over their freshman posttest score (a normalized gain of about 70%, while their performance on the remaining 17 questions is best characterized as a loss of approximately 50% of the material learned in the freshman course. On multiple-choice questions covering advanced physics concepts, the mean score of the participants was about 50% lower than the average performance of freshmen. Although attitudinal survey results indicate that almost half the seniors feel the specific mechanics course content is unlikely to be useful to them, a significant majority (75%–85% feel that physics does teach valuable problem solving skills, and an overwhelming majority believe that mechanics should remain a required course at MIT.

  16. Electrical stimulation counteracts muscle decline in seniors.

    Science.gov (United States)

    Kern, Helmut; Barberi, Laura; Löfler, Stefan; Sbardella, Simona; Burggraf, Samantha; Fruhmann, Hannah; Carraro, Ugo; Mosole, Simone; Sarabon, Nejc; Vogelauer, Michael; Mayr, Winfried; Krenn, Matthias; Cvecka, Jan; Romanello, Vanina; Pietrangelo, Laura; Protasi, Feliciano; Sandri, Marco; Zampieri, Sandra; Musaro, Antonio

    2014-01-01

    The loss in muscle mass coupled with a decrease in specific force and shift in fiber composition are hallmarks of aging. Training and regular exercise attenuate the signs of sarcopenia. However, pathologic conditions limit the ability to perform physical exercise. We addressed whether electrical stimulation (ES) is an alternative intervention to improve muscle recovery and defined the molecular mechanism associated with improvement in muscle structure and function. We analyzed, at functional, structural, and molecular level, the effects of ES training on healthy seniors with normal life style, without routine sport activity. ES was able to improve muscle torque and functional performances of seniors and increased the size of fast muscle fibers. At molecular level, ES induced up-regulation of IGF-1 and modulation of MuRF-1, a muscle-specific atrophy-related gene. ES also induced up-regulation of relevant markers of differentiating satellite cells and of extracellular matrix remodeling, which might guarantee shape and mechanical forces of trained skeletal muscle as well as maintenance of satellite cell function, reducing fibrosis. Our data provide evidence that ES is a safe method to counteract muscle decline associated with aging.

  17. Acceptance in the domestic environment: the experience of senior housing for lesbian, gay, bisexual, and transgender seniors.

    Science.gov (United States)

    Sullivan, Kathleen M

    2014-01-01

    The social environment impacts the ability of older adults to interact successfully with their community and age-in-place. This study asked, for the first time, residents of existing Lesbian, Gay, Bisexual, and Transgender (LGBT) senior living communities to explain why they chose to live in those communities and what, if any, benefit the community afforded them. Focus groups were conducted at 3 retirement communities. Analysis found common categories across focus groups that explain the phenomenon of LGBT senior housing. Acceptance is paramount for LGBT seniors and social networks expanded, contrary to socioemotional selectivity theory. Providers are encouraged to develop safe spaces for LGBT seniors.

  18. Stiffness Analysis and Improvement of Bolt-Plate Contact Assemblies

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Pedersen, Pauli

    2008-01-01

    In a previous study it was shown that, a simplified expression for the stiffness of the plate member in a bolt-plate assembly can be found. The stiffnesses of the bolt and the connected plates are the primary quantities that control the lifetime of a dynamically loaded connection. The present study...... of stiffnesses is extended to include different material parameters by including the influence of Poisson's ratio. Two simple practical formulas are suggested and their accuracies are documented for different bolts and different material (Poisson's ratio). Secondly, the contact analysis between the bolt head...... and the plate is extended by the possibility of designing a gap, that is, a nonuniform distance between the bolt and plate before prestressing. Designing the gap function generates the possibility for a better stress field by which the stiffness of the bolt is lowered, and at the same time the stiffness...

  19. Efficient Method for Calculating the Composite Stiffness of Parabolic Leaf Springs with Variable Stiffness for Vehicle Rear Suspension

    Directory of Open Access Journals (Sweden)

    Wen-ku Shi

    2016-01-01

    Full Text Available The composite stiffness of parabolic leaf springs with variable stiffness is difficult to calculate using traditional integral equations. Numerical integration or FEA may be used but will require computer-aided software and long calculation times. An efficient method for calculating the composite stiffness of parabolic leaf springs with variable stiffness is developed and evaluated to reduce the complexity of calculation and shorten the calculation time. A simplified model for double-leaf springs with variable stiffness is built, and a composite stiffness calculation method for the model is derived using displacement superposition and material deformation continuity. The proposed method can be applied on triple-leaf and multileaf springs. The accuracy of the calculation method is verified by the rig test and FEA analysis. Finally, several parameters that should be considered during the design process of springs are discussed. The rig test and FEA analytical results indicate that the calculated results are acceptable. The proposed method can provide guidance for the design and production of parabolic leaf springs with variable stiffness. The composite stiffness of the leaf spring can be calculated quickly and accurately when the basic parameters of the leaf spring are known.

  20. Capital Structure and Managerial Compensation : The Effects of Renumeration Seniority

    NARCIS (Netherlands)

    Calcagno, R.; Renneboog, L.D.R.

    2004-01-01

    We show that the relative seniority of debt and managerial compensation has important implications on the design of remuneration contracts.Whereas the traditional literature assumes that debt is senior to remuneration, we show that this is frequently not the case according to bankruptcy regulation a

  1. 75 FR 35877 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2010-06-23

    ... INFORMATION CONTACT: Paula Chandler, Director of Human Resources, (202) 245-0340. SUPPLEMENTARY INFORMATION: Title 5 U.S.C. 4314 requires that each agency implement a performance appraisal system making senior... evaluate the initial appraisal of a senior executive's performance by the supervisor and to...

  2. Stress and the High School Senior: Implications for Instruction.

    Science.gov (United States)

    Amen, John; Reglin, Gary

    1992-01-01

    A recent survey found that 90 percent of high school seniors/respondents perceived the world as stressful and the majority of people as phony. These views may partly explain the high suicide, pregnancy, dropout, and drug usage rates among high school seniors. Teachers can help students overcome stress by modeling coping strategies and providing…

  3. Sustainability of Seniors in Low- and Middle-Income Societies

    Science.gov (United States)

    Jesmin, Syeda S.; Amin, Iftekhar; Ingman, Stan

    2011-01-01

    As low income societies are aging rapidly, government and families face challenges to support the seniors, who are already at greater risks of being negatively affected by many other social, cultural, and global changes occurring around them. This paper reviews some of the major challenges faced by seniors in China, India, Mexico, and African…

  4. QULITY EDUCATION IN ENGLISH TEACHING IN SENIOR HIGH SCHOOL

    Institute of Scientific and Technical Information of China (English)

    李学弟

    2009-01-01

    Quality education may contain more and need higher standard with the nation-wide practice of the new curriculum in senior high school.As teachers of senior English,we should try to study the new curriculum to improve the students' overall quality and the efficiency of English teaching

  5. Board and Senior Management Alignment on School Strategy

    Science.gov (United States)

    Sarros, James C.; Sarros, Anne M.; Cooper, Brian K.; Santora, Joseph C.; Baker, Robin

    2016-01-01

    This study examines the degree to which senior executive members of a school's decision-making team (senior management team and board of directors) are aligned on fundamental principles of school strategy. Our study is based on a conceptual framework of strategic leadership as it applies in an Australian independent school context. We also examine…

  6. A Successful Senior Seminar: Unsolved Problems in Number Theory

    Science.gov (United States)

    Styer, Robert

    2014-01-01

    The "Unsolved Problems in Number Theory" book by Richard Guy provides nice problems suitable for a typical math major. We give examples of problems that have worked well in our senior seminar course and some nice results that senior math majors can obtain.

  7. 75 FR 62501 - Senior Executive Service Performance Review Board: Update

    Science.gov (United States)

    2010-10-12

    ... From the Federal Register Online via the Government Publishing Office AGENCY FOR INTERNATIONAL DEVELOPMENT Senior Executive Service Performance Review Board: Update AGENCY: U.S. Agency For International... appointing authority relative to the performance of ] the senior executive. This notice updates...

  8. The Cooperative Learning in Senior English classroom Teaching

    Institute of Scientific and Technical Information of China (English)

    汪明语

    2014-01-01

    According to the requirements of the new curriculum standard of Senior English, students should be the core of the English classroom. This essay explores the use of cooperative learning in Senior English classroom. It highlights the essential role that cooperative learning should play in the English teaching process and it also discusses some practical methods of applying this useful strategy.

  9. Senior Centers and Policy Advocacy: Changing Public Perceptions

    Science.gov (United States)

    Pardasani, Manoj; Goldkind, Lauri

    2012-01-01

    As critical components of the aging continuum of care, senior centers promote older adult health and well-being by providing opportunities for recreation, socialization, nutrition, health education, and access to vital social services. Nationally, a vast network of 11,000 senior centers serves over four million older adults annually. As the United…

  10. Capital Structure and Managerial Compensation : The Effects of Renumeration Seniority

    NARCIS (Netherlands)

    Calcagno, R.; Renneboog, L.D.R.

    2004-01-01

    We show that the relative seniority of debt and managerial compensation has important implications on the design of remuneration contracts.Whereas the traditional literature assumes that debt is senior to remuneration, we show that this is frequently not the case according to bankruptcy regulation

  11. Senior Secondary School Children's Understanding of Plant Nutrition

    Science.gov (United States)

    Mosothwane, Modise

    2011-01-01

    The purpose of this study was to assess children's understanding of plant nutrition. The research was done on a sample of secondary school pupils in the age range of 16 to 19 years in two senior secondary schools in Botswana. The sample contained 137 senior secondary pupils all in their final year of study. These children were above average…

  12. National Issues Forums: Seniors/Community Connection. Final Report.

    Science.gov (United States)

    Fisher, Suzanne M.

    A project was conducted to incorporate the Kettering Foundation's National Issues Forums (NIFs) into two senior citizen centers in Pennsylvania. The NIFs provide a process for sharing thoughts and opinions about areas of pressing national concern in an open exchange of all participants' opinions. An inservice training of senior center staff on…

  13. Developing Good Habits of Learning English from Senior One

    Institute of Scientific and Technical Information of China (English)

    黄益琴

    2009-01-01

    Senior one is the most important period of the whole senior stage, it h necessary for students to form good habits of learning at the beginning. Based on the discussion of necessity of forming good habits, this paper talks about the methods of cultivating students' good habits of learning and concludes that good habits can benefit them a lot.

  14. Burnout in College Seniors Preparing for the Human Services Professions.

    Science.gov (United States)

    Edwards, James G.

    The Maslach Burnout Inventory (MBI) was used to assess the level and intensity of burnout in 165 California State University at Long Beach college seniors preparing for the human services professions, specifically teaching, nursing, criminal justice, and social welfare. A comparison group of 80 engineering seniors was also assessed. The 40-item…

  15. 77 FR 35752 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2012-06-14

    ... INFORMATION: Title 5 U.S.C. 4314 requires that each agency implement a performance appraisal system making... review and evaluate the initial appraisal of a senior executive's performance by the supervisor and to... Surface Transportation Board Senior Executive Service Performance Review Board AGENCY:...

  16. The afterlife for retiring deans and other senior medical administrators.

    Science.gov (United States)

    Tannen, Richard L

    2008-11-01

    Career options for individuals leaving the administrative role as dean of a school of medicine or other senior administrative positions are considered. Options discussed include retirement and a variety of other positions both within schools of medicines and in other venues. Many opportunities exist for a challenging and fulfilling career path after leaving the role as a senior administrator in an academic medical center.

  17. Bridging the Gap between Senior Citizens and Young People.

    Science.gov (United States)

    Iannacone, George; Skelly, Joan

    1985-01-01

    This article describes a school district's programs that build relationships between the schools and the local senior citizens, including a grandparent program, developmental seminars, and a prom for senior citizens put on by the students. Also described are some keys to making such programs work, and the benefits. (DCS)

  18. 77 FR 65581 - Verizon Business Networks Services, Inc., Senior Analyst, Service Program Delivery (SA-SPD...

    Science.gov (United States)

    2012-10-29

    ... Employment and Training Administration Verizon Business Networks Services, Inc., Senior Analyst, Service..., 2012, applicable to workers and former workers of Verizon Business Network Services, Inc., Senior... hereby issued as follows: ] All workers of Verizon Business Network Services, Inc., Senior...

  19. Assessing seniors' user experience (UX) of exergames for balance training

    DEFF Research Database (Denmark)

    Nawaz, Ather; Skjæret, Nina; Ystmark, Kristine;

    2014-01-01

    . This study aims to evaluate user experience and preferences of exergame technologies to train balance and to identify different factors that affect seniors' intention to use exergames. Fourteen healthy senior citizens played three different stepping exergames in a laboratory setting. Seniors' experience......Exergames technologies are increasingly used to help people achieve their exercise requirements including balance training. However, little is known about seniors' user experience of exergame technology for balance training and what factors they consider most important for using the exergames...... of the exergames and their preference to use exergames was assessed using a semi-structured interview, the system usability scale (SUS), and card ranking. The results of the study showed that in order for seniors to use exergames to train their balance, the exergames should particularly focus on challenging tasks...

  20. Age-related greater Achilles tendon compliance is not associated with larger plantar flexor muscle fascicle strains in senior women.

    Science.gov (United States)

    Csapo, R; Malis, V; Hodgson, J; Sinha, S

    2014-04-15

    The aim of the present study was to test the hypothesis that the age-associated decrease of tendon stiffness would necessitate greater muscle fascicle strains to produce similar levels of force during isometric contraction. Greater fascicle strains could force sarcomeres to operate in less advantageous regions of their force-length and force-velocity relationships, thus impairing the capacity to generate strong and explosive contractions. To test this hypothesis, sagittal-plane dynamic velocity-encoded phase-contrast magnetic resonance images of the gastrocnemius medialis (GM) muscle and Achilles tendon (AT) were acquired in six young (YW; 26.1 ± 2.3 yr) and six senior (SW; 76.7 ± 8.3 yr) women during submaximal isometric contraction (35% maximum voluntary isometric contraction) of the plantar flexor muscles. Multiple GM fascicle lengths were continuously determined by automatically tracking regions of interest coinciding with the end points of muscle fascicles evenly distributed along the muscle's proximo-distal length. AT stiffness and Young's modulus were measured as the slopes of the tendon's force-elongation and stress-strain curves, respectively. Despite significantly lower AT stiffness at older age (YW: 120.2 ± 52.3 N/mm vs. SW: 53.9 ± 44.4 N/mm, P = 0.040), contraction-induced changes in GM fascicle lengths were similar in both age groups at equal levels of absolute muscular force (4-5% fascicle shortening in both groups), and even significantly larger in YW (YW: 11-12% vs. SW: 6-8% fascicle shortening) at equal percentage of maximum voluntary contraction. These results suggest that factors other than AT stiffness, such as age-associated changes in muscle composition or fascicle slack, might serve as compensatory adaptations, limiting the degree of fascicle strains upon contraction.

  1. Leptin and endothelial function in the elderly: the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study.

    Science.gov (United States)

    Gonzalez, Manuel; Lind, Lars; Söderberg, Stefan

    2013-06-01

    Leptin levels are elevated in obese humans. Several studies have shown an association between hyperleptinemia and development of atherosclerosis and cardiovascular disease (CVD), but the relationship between leptin and vascular function remains unclear. To evaluate associations between circulating plasma leptin and measures of vascular function in a large sample of elderly individuals from the community. This cross-sectional study included 1016 subjects aged 70 (50% women) from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). The invasive technique forearm plethysmography with intra-arterial infusions of acetylcholine and sodium nitroprusside was used for estimation of endothelial dependent vasodilatation (EDV) and endothelial independent vasodilatation (EIDV), respectively, in resistance arteries, and the non-invasive technique ultrasound assessed flow mediated vasodilation (FMD) in conduit arteries. The aortic augmentation index (AoAI), a surrogate measure of arterial stiffness, was evaluated by pulse wave analysis. Associations of vascular function, arterial stiffness and blood pressure with leptin were explored. In sex-adjusted models, high levels of leptin were inversely associated with EDV and EIDV. These associations remained after stratification for sex, traditional risk factors of CVD and insulin resistance, but were attenuated after taking a measure of obesity (body mass index) into account. In addition, leptin associated with arterial stiffness and systolic and diastolic blood pressure. Hyperleptinemia associated inversely with vasodilatation in resistance arteries. Furthermore, hyperleptinemia associated with arterial stiffness and hypertension. These associations were attenuated after adjusting for body mass index suggesting that leptin may be the mediator between obesity and impaired vascular function. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Noninvasive pulse wave analysis for the determination of central artery stiffness

    DEFF Research Database (Denmark)

    Wittrock, Marc; Scholze, Alexandra; Compton, Friederike;

    2009-01-01

    Central artery stiffness predicts cardiovascular structural damage and clinical outcome. It is controversial whether central artery stiffness can be determined by noninvasive measurements. We compared noninvasive determination of central artery stiffness obtained from applanation tonometry of the...

  3. Controlled Unusual Stiffness of Mechanical Metamaterials.

    Science.gov (United States)

    Lee, Wooju; Kang, Da-Young; Song, Jihwan; Moon, Jun Hyuk; Kim, Dongchoul

    2016-02-03

    Mechanical metamaterials that are engineered with sub-unit structures present unusual mechanical properties depending on the loading direction. Although they show promise, their practical utility has so far been somewhat limited because, to the best of our knowledge, no study about the potential of mechanical metamaterials made from sophisticatedly tailored sub-unit structures has been made. Here, we present a mechanical metamaterial whose mechanical properties can be systematically designed without changing its chemical composition or weight. We study the mechanical properties of triply periodic bicontinuous structures whose detailed sub-unit structure can be precisely fabricated using various sub-micron fabrication methods. Simulation results show that the effective wave velocity of the structures along with different directions can be designed to introduce the anisotropy of stiffness by changing a volume fraction and aspect ratio. The ratio of Young's modulus to shear modulus can be increased by up to at least 100, which is a 3500% increase over that of isotropic material (2.8, acrylonitrile butadiene styrene). Furthermore, Poisson's ratio of the constituent material changes the ratio while Young's modulus does not influence it. This study presents the promising potential of mechanical metamaterials for versatile industrial and biomedical applications.

  4. STIFFNESS MODIFICATION OF COTTON IN CHITOSAN TREATMENT

    Directory of Open Access Journals (Sweden)

    CAMPOS Juan

    2017-05-01

    Full Text Available Chitosan is a biopolymer obtained from chitin, and among their most important aspects highlights its applications in a lot of industrial sectors due to its intrinsic properties, especially in the textile sector. In the last years, chitosan is widely used in the cotton and wool finishing processes due to its bond between them and its properties as an antifungical and antimicrobial properties. In this paper three different molecular weight chitosan are used in the finishing process of cotton to evaluate its influence in the surface properties modification. In order to evaluate the effect of the treatment with chitosan, flexural stiffness test is performed in warp and weft direction, and then the total value is calculated. The cotton fabric is treated with 5 g/L of different types of chitosan in an impregnation bath. This study shows the extent of surface properties modification of the cotton provided by three types of chitosan treatment. The results show that all types of chitosan modify the cotton flexural rigidity properties but the one which modifies it in a relevant manner is chitosan originated from shrimps. Chitosan, textile, flexural stiffnes, chitin, cotton.

  5. Variable Volumetric Stiffness Fluid Mount Design

    Directory of Open Access Journals (Sweden)

    Nader Vahdati

    2004-01-01

    Full Text Available Passive fluid mounts are commonly used in the automotive and aerospace applications to isolate the cabin from the engine noise and vibration. Due to manufacturing and material variabilities, no two identical fluid mount designs act the same. So, fluid mounts are tuned one by one before it is shipped out to customers. In some cases, for a batch of fluid mounts manufactured at the same time, one is tuned and the rest is set to the same settings. In some cases they are shipped as is with its notch frequency not being in its most optimum location. Since none of the passive fluid mount parameters are controllable, the only way to tune the mount is to redesign the mount by changing fluid, changing inertia track length or diameter, or changing rubber stiffness. This trial and error manufacturing process is very costly. To reduce the fluid mount notch frequency tuning cycle time, a new fluid mount design is proposed. In this new fluid mount design, the notch frequency can be easily modified without the need for any redesigns. In this paper, the new design concept, and its mathematical model and simulation results will be presented.

  6. Diagnosis and management of osteoporosis in the older senior

    Directory of Open Access Journals (Sweden)

    Sheryl F Vondracek

    2009-03-01

    Full Text Available Sheryl F Vondracek, Sunny A LinneburDepartment of Clinical Pharmacy, School of Pharmacy C238-L15, University of Colorado Denver, Aurora, CO, USAAbstract: The older senior is at high risk for osteoporosis. It is important for healthcare providers to be fully aware of the potential risks and benefits of diagnosing and treating osteoporosis in the older senior population. Data indicate that bone mineral density testing is under-utilized and drug therapy is often not initiated when indicated in this population. Bone mineral density testing with central dual energy x-ray absorptiometry is essential and cost-effective in this population. All older seniors should be educated on a bone-healthy lifestyle including age-appropriate weightbearing exercise and smoking cessation if necessary. It is important to remember that falls play a very important role in the risk for osteoporotic fractures, especially in the older senior. All older seniors should be evaluated annually for falls and strategies should be implemented to reduce fall risk in this population. The risk for vitamin D insufficiency and deficiency is high in the older senior and can contribute to falls and fractures. Adequate intakes of calcium and vitamin D are important and deficiencies need to be treated. Data on osteoporosis drug therapy in the older senior are lacking. Based on data from subgroup analyses of large osteoporosis trials in postmenopausal women, current osteoporosis therapies appear safe and efficacious in the older senior and most will live long enough to derive a benefit from these therapies. Further studies are needed in older seniors, especially men, to better understand the risks and benefits of pharmacologic therapy for the management of osteoporosis.Keywords: osteoporosis, aged, elderly, eighty and over, senior, diphosphonates

  7. Paid caregiver motivation, work conditions, and falls among senior clients.

    Science.gov (United States)

    Lindquist, Lee A; Tam, Karen; Friesema, Elisha; Martin, Gary J

    2012-01-01

    The purpose of this study was to determine the motivation of paid non-familial caregivers of seniors, understand more about their work conditions, and identify any links to negative outcomes among their senior clients. Ninety-eight paid caregivers (eighty-five female and thirteen male), recruited from multiple sites (i.e. senior centers, shopping malls, local parks, lobbies of senior apartments, caregiver agency meetings) completed face-to-face questionnaires and semi-structured interviews. We found that 60.7% of participants chose to become a caregiver because they enjoyed being with seniors while 31.7% were unable to obtain other work, and 8.2% stated it was a prerequisite to a different health related occupation. Caregivers stated that the most challenging conditions of their work were physical lifting (24.5%), behavioral and psychological symptoms of dementia (24.5%), senior depression/mood changes (18.4%), attachment with impending death (8.2%), missing injuries to client (5.1%), lack of sleep (4.1%), and lack of connection with outside world (3.1%). Caregivers who reported that the best part of their job was the salary, flexible hours, and ease of work were significantly more likely to have clients who fell and fractured a bone than those who enjoyed being with seniors (job characteristics, 62.5% vs. senior enjoyment, 25.6%; pmotivated commonly by their love of seniors and also by their lack of other job opportunities. Paid caregivers frequently face challenging work conditions. When seeking a caregiver for a senior, motivation of the caregiver should be considered when hiring. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  8. Research training of Senior High School teachers

    Directory of Open Access Journals (Sweden)

    Margarita Oropeza Largher

    2015-07-01

    Full Text Available The paper focuses the development of research competence as a component of the teachers’ training program in Mexico. The objective is to analyze current trends in approaching training in research by the teachers of Senior High Schools. Documents and bibliographic sources were consulted to construct a theoretical framework; surveys, interviews and supervising lessons were used to gather information for a diagnosis of the staff development. The findings include a diagnosis of staff competence in education researching, the promotion of project method among pupils, and a contextual approach to research competence in Mexican environment, leading to arrive at the conclusion that teachers are facing a two challenges, one related to self-development and the other connected to pupils’ education.

  9. Investigation of the torsional stiffness of flexible disc coupling

    Science.gov (United States)

    Buryy, A.; Simonovsky, V.; Obolonik, V.

    2017-08-01

    Calculation of flexible coupling torsional stiffness is required when analyzing the torsional vibrations of the reciprocating machinery train. While having the lowest torsional stiffness of all the elements of the train, flexible coupling has a significant influence on the natural frequencies of torsional vibration. However, considering structural complexity of coupling, precise definition of its torsional stiffness is quite a difficult task. The paper presents a method for calculating the torsional stiffness of flexible disc coupling based on the study of its finite element model response under the action of torque. The analysis of the basic parameters that quantitatively and qualitatively affect the coupling torsional stiffness has been also provided. The results of the calculation as well as model adequacy, sufficient for practical application, have been confirmed at the experimental measurement of flexible disc coupling torsional stiffness. The obtained elastic characteristics (dependences of applied torque and torsional stiffness versus twist angle) are nonlinear in the initial stage of loading. This feature should be taken into account when creating reliable mathematical models of torsional vibrations of reciprocating machinery trains containing flexible disc couplings.

  10. Stiffness identification of four-point-elastic-support rigid plate

    Institute of Scientific and Technical Information of China (English)

    彭利平; 刘初升; 武继达; 王帅

    2015-01-01

    As the stiffness of the elastic support varies with the physical-chemical erosion and mechanical friction, model catastrophe of a single degree-of-freedom (DOF) isolation system may occur. A 3-DOF four-point-elastic-support rigid plate (FERP) structure is presented to describe the catastrophic isolation system. Based on the newly-established structure, theoretical derivation for stiffness matrix calculation by free response (SMCbyFR) and the method of stiffness identification by stiffness matrix disassembly (SIbySMD) are proposed. By integrating the SMCbyFR and the SIbySMD and defining the stiffness assurance criterion (SAC), the procedures for stiffness identification of a FERP structure (SIFERP) are summarized. Then, a numerical example is adopted for the SIFERP validation, in which the simulated tested free response data are generated by the numerical methods, and operation for filtering noise is conducted to imitate the practical application. Results in the numerical example demonstrate the feasibility and accuracy of the developed SIFERP for stiffness identification.

  11. Stiffness and Angular Deflection analysis of Revolute Manipulator

    Directory of Open Access Journals (Sweden)

    Pundru Srinivasa Rao

    2014-03-01

    Full Text Available This paper proposed to determine the Cartesian stiffness matrix and angular deflection analysis of revolute manipulator. The selected manipulator has rigid fixed link, two movable links and two rotary joints with joint stiffness coefficients are taken into account. The kinematic model of revolute joint manipulator has considered as a planar kinematic chain, which is composed by rigid fixed link and two revolute joints with clearance and deformable elements. The calculation of stiffness matrix depends on Jacobian matrix and change of configuration. The rotational joints are modeled as torsion springs with the same stiffness constant. The relative angular deflections are proportional to the actuated torques taken into account. The subject of this paper has to describe a method for stiffness analysis of serial manipulator. In the present work is to derive the stiffness matrix and angular deflection equations in the Robotic manipulator under the consideration of two-link optimum geometry model for rotary joint manipulator. The stiffness values are measured by displacements of its revolute links loaded by force.

  12. Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells

    Science.gov (United States)

    Eisenberg, Jessica L; Safi, Asmahan; Wei, Xiaoding; Espinosa, Horacio D; Budinger, GR Scott; Takawira, Desire; Hopkinson, Susan B; Jones, Jonathan CR

    2012-01-01

    Aim The aim of the study was to address whether a stiff substrate, a model for pulmonary fibrosis, is responsible for inducing changes in the phenotype of alveolar epithelial cells (AEC) in the lung, including their deposition and organization of extracellular matrix (ECM) proteins. Methods Freshly isolated lung AEC from male Sprague Dawley rats were seeded onto polyacrylamide gel substrates of varying stiffness and analyzed for expression and organization of adhesion, cytoskeletal, differentiation, and ECM components by Western immunoblotting and confocal immunofluorescence microscopy. Results We observed that substrate stiffness influences cell morphology and the organization of focal adhesions and the actin cytoskeleton. Surprisingly, however, we found that substrate stiffness has no influence on the differentiation of type II into type I AEC, nor does increased substrate stiffness lead to an epithelial–mesenchymal transition. In contrast, our data indicate that substrate stiffness regulates the expression of the α3 laminin subunit by AEC and the organization of both fibronectin and laminin in their ECM. Conclusions An increase in substrate stiffness leads to enhanced laminin and fibronectin assembly into fibrils, which likely contributes to the disease phenotype in the fibrotic lung. PMID:23204878

  13. Simvastatin Ameliorates Matrix Stiffness-Mediated Endothelial Monolayer Disruption.

    Science.gov (United States)

    Lampi, Marsha C; Faber, Courtney J; Huynh, John; Bordeleau, Francois; Zanotelli, Matthew R; Reinhart-King, Cynthia A

    2016-01-01

    Arterial stiffening accompanies both aging and atherosclerosis, and age-related stiffening of the arterial intima increases RhoA activity and cell contractility contributing to increased endothelium permeability. Notably, statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors whose pleiotropic effects include disrupting small GTPase activity; therefore, we hypothesized the statin simvastatin could be used to attenuate RhoA activity and inhibit the deleterious effects of increased age-related matrix stiffness on endothelial barrier function. Using polyacrylamide gels with stiffnesses of 2.5, 5, and 10 kPa to mimic the physiological stiffness of young and aged arteries, endothelial cells were grown to confluence and treated with simvastatin. Our data indicate that RhoA and phosphorylated myosin light chain activity increase with matrix stiffness but are attenuated when treated with the statin. Increases in cell contractility, cell-cell junction size, and indirect measurements of intercellular tension that increase with matrix stiffness, and are correlated with matrix stiffness-dependent increases in monolayer permeability, also decrease with statin treatment. Furthermore, we report that simvastatin increases activated Rac1 levels that contribute to endothelial barrier enhancing cytoskeletal reorganization. Simvastatin, which is prescribed clinically due to its ability to lower cholesterol, alters the endothelial cell response to increased matrix stiffness to restore endothelial monolayer barrier function, and therefore, presents a possible therapeutic intervention to prevent atherogenesis initiated by age-related arterial stiffening.

  14. Martial arts training attenuates arterial stiffness in middle aged adults.

    Science.gov (United States)

    Douris, Peter C; Ingenito, Teresa; Piccirillo, Barbara; Herbst, Meredith; Petrizzo, John; Cherian, Vincen; McCutchan, Christopher; Burke, Caitlin; Stamatinos, George; Jung, Min-Kyung

    2013-09-01

    Arterial stiffness increases with age and is related to an increased risk of coronary artery disease. Poor trunk flexibility has been shown to be associated with arterial stiffness in middle-aged subjects. The purpose of our research study was to measure arterial stiffness and flexibility in healthy middle-aged martial artists compared to age and gender matched healthy sedentary controls. Ten martial artists (54.0 ± 2.0 years), who practice Soo Bahk Do (SBD), a Korean martial art, and ten sedentary subjects (54.7 ± 1.8 years) for a total of twenty subjects took part in this cross-sectional study. Arterial stiffness was assessed in all subjects using pulse wave velocity (PWV), a recognized index of arterial stiffness. Flexibility of the trunk and hamstring were also measured. The independent variables were the martial artists and matched sedentary controls. The dependent variables were PWV and flexibility. There were significant differences, between the SBD practitioners and sedentary controls, in PWV (P = 0.004), in trunk flexibility (P= 0.002), and in hamstring length (P= 0.003). The middle-aged martial artists were more flexible in their trunk and hamstrings and had less arterial stiffness compared to the healthy sedentary controls. The flexibility component of martial art training or flexibility exercises in general may be considered as a possible intervention to reduce the effects of aging on arterial stiffness.

  15. Simvastatin Ameliorates Matrix Stiffness-Mediated Endothelial Monolayer Disruption.

    Directory of Open Access Journals (Sweden)

    Marsha C Lampi

    Full Text Available Arterial stiffening accompanies both aging and atherosclerosis, and age-related stiffening of the arterial intima increases RhoA activity and cell contractility contributing to increased endothelium permeability. Notably, statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase inhibitors whose pleiotropic effects include disrupting small GTPase activity; therefore, we hypothesized the statin simvastatin could be used to attenuate RhoA activity and inhibit the deleterious effects of increased age-related matrix stiffness on endothelial barrier function. Using polyacrylamide gels with stiffnesses of 2.5, 5, and 10 kPa to mimic the physiological stiffness of young and aged arteries, endothelial cells were grown to confluence and treated with simvastatin. Our data indicate that RhoA and phosphorylated myosin light chain activity increase with matrix stiffness but are attenuated when treated with the statin. Increases in cell contractility, cell-cell junction size, and indirect measurements of intercellular tension that increase with matrix stiffness, and are correlated with matrix stiffness-dependent increases in monolayer permeability, also decrease with statin treatment. Furthermore, we report that simvastatin increases activated Rac1 levels that contribute to endothelial barrier enhancing cytoskeletal reorganization. Simvastatin, which is prescribed clinically due to its ability to lower cholesterol, alters the endothelial cell response to increased matrix stiffness to restore endothelial monolayer barrier function, and therefore, presents a possible therapeutic intervention to prevent atherogenesis initiated by age-related arterial stiffening.

  16. Fabrication of Janus hydrogels with stiffness gradient using drop coalescence

    Science.gov (United States)

    Lee, Donghee; Golden, Kale; Ryu, Sangjin

    2016-11-01

    The stiffness of the extracellular matrix (ECM) regulates cellular behaviors, and polyacrylamide (PAAM) gels with stiffness gradient have been used to simulate inhomogeneous ECM and to study the effects of the ECM stiffness on cells. Such hydrogel substrates with stiffness gradient can be fabricated with relatively complicated methods using microfluidics and moving masks. In our study, we develop a simpler method for fabricating Janus hydrogel which has a gradient of stiffness. Two prepolymer solutions were prepared for soft and stiff gel compositions, respectively, and one drop of each solution was placed on a hydrophobic patterned glass. Then, these two drops were gently squeezed by another glass being slowly lowered until coalescence, and gel polymerization was initiated after a certain time period for mixing. The motion of the drops was guided by the hydrophobic pattern. AFM nano-indentation showed that the fabricated Janus PAAM gels have a stiffness gradient which could be controlled by increasing mixing time. This study was supported by Bioengineering for Human Health Grant from UNL and UNMC.

  17. 76 FR 39361 - AmeriCorps State/National, Senior Companions, Foster Grandparents, and Retired and Senior...

    Science.gov (United States)

    2011-07-06

    ... History Check regulations to require grantees to conduct and document criminal history checks (including both state criminal history checks and FBI fingerprint checks) on Senior Companions, Foster Grandparents, Retired Senior Volunteer Program grant-funded staff, Learn and Serve America, AmeriCorps...

  18. Students' approaches to learning when entering higher education: Differences between students with senior general secondary and senior secondary educational backgrounds.

    NARCIS (Netherlands)

    Marcel A. Croon; Johan M.M. van der Sanden; Dr. A. Bakx; Dr. Cyrille A.C. Van Bragt

    2007-01-01

    Recently, more students have entered Dutch higher education. This is a consequence of the possibility to offer students to enter higher education, with a certificate from senior secondary education (SSVE). In earlier days most students in higher education had passed senior general secondary

  19. Students' approaches to learning when entering higher education: Differences between students with senior general secondary and senior secondary educational backgrounds.

    NARCIS (Netherlands)

    Bragt, Cyrille A.C. van; Bakx, Anouke W.E.A.; Sanden, Johan M.M. van der; Croon, Marcel A.

    2007-01-01

    Recently, more students have entered Dutch higher education. This is a consequence of the possibility to offer students to enter higher education, with a certificate from senior secondary education (SSVE). In earlier days most students in higher education had passed senior general secondary educatio

  20. Mechanical engineering capstone senior design textbook

    Science.gov (United States)

    Barrett, Rolin Farrar, Jr.

    This textbook is intended to bridge the gap between mechanical engineering equations and mechanical engineering design. To that end, real-world examples are used throughout the book. Also, the material is presented in an order that follows the chronological sequence of coursework that must be performed by a student in the typical capstone senior design course in mechanical engineering. In the process of writing this book, the author surveyed the fifty largest engineering schools (as ranked by the American Society of Engineering Education, or ASEE) to determine what engineering instructors are looking for in a textbook. The survey results revealed a clear need for a textbook written expressly for the capstone senior design course as taught throughout the nation. This book is designed to meet that need. This text was written using an organizational method that the author calls the General Topics Format. The format gives the student reader rapid access to the information contained in the text. All manufacturing methods, and some other material presented in this text, have been presented using the General Topics Format. The text uses examples to explain the importance of understanding the environment in which the product will be used and to discuss product abuse. The safety content contained in this text is unique. The Safety chapter teaches engineering ethics and includes a step-by-step guide to resolving ethical conflicts. The chapter includes explanations of rules, recommendations, standards, consensus standards, key safety concepts, and the legal implications of product failure. Key design principles have been listed and explained. The text provides easy-to-follow design steps, helpful for both the student and new engineer. Prototyping is presented as consisting of three phases: organization, building, and refining. A chapter on common manufacturing methods is included for reference.

  1. Large Artery Stiffness Assessment Using SphygmoCor Technology

    Science.gov (United States)

    Butlin, Mark; Qasem, Ahmad

    2017-01-01

    Large artery stiffness assessment has been an integral part of the SphygmoCor technology since 1998. Aortic stiffness is approximated with non-invasive measurement of carotid-femoral pulse wave velocity, with improvements made with time to make the assessment procedure quicker and more user independent. Also standard in the devices is the ability to reliably calculate the central aortic waveform shape from a peripheral pressure waveform from either the brachial or radial artery. This waveform contains much information beyond peak and trough (systolic and diastolic pressure). Relative waveform features such as the augmentation index, wave reflection magnitude, reflection time index, and subendocardial viability ratio are parameters that are influenced by the stiffness of systemic arteries. This article briefly describes these parameters related to large artery stiffness and provides reference to validation and repeatability studies relative to the clinical use of the SphygmoCor devices. It is beyond the scope to review here the 424 original research articles that have employed SphygmoCor devices in measuring arterial stiffness. Instead, the method of measurement across the devices is described, including tonometry, volumetric displacement through cuff placement around limbs, and ambulatory monitoring. Key population and subpopulation studies are cited where the average stiffness parameter progression with age and gender, as measured by SphygmoCor devices, is quantified in the healthy and general population. Finally, with reference to guidelines from working groups on arterial stiffness and hypertension, the clinical utility of large artery stiffness measurement is discussed in the context of the arterial stiffness parameters provided by the SphygmoCor systems. PMID:28229053

  2. 78 FR 60816 - Senior Executive Services (SES) Performance Review Board: Update

    Science.gov (United States)

    2013-10-02

    ...; ] AGENCY FOR INTERNATIONAL DEVELOPMENT Senior Executive Services (SES) Performance Review Board: Update... the performance of the senior executive. This notice updates the membership of the USAID OIG's...

  3. A modified beam stiffness matrix for superconductor elements

    Energy Technology Data Exchange (ETDEWEB)

    Gori, R.; Schrefler, B.A. (Padua Univ. (Italy). Ist. di Scienza e Tecnica delle Costruzioni)

    1989-10-01

    The components of the stiffness matrix of superconductor elements are derived taking into account the effects of the wrapping of superconductor strands around the internal insulating strip and of possible stabilizing profiles around conductor core. It is already known that the inclination of the strands referred to the longitudinal axis of the superconductor produces a reduction of the axial stiffness and a considerable increase in torsional stiffness. Here also the effects of bending are taken into account, completing hence the previous investigation. Examples relating to superconductors proposed for the Toroidal Field Coil of the Next European Torus are shown. In that instance the strand transposition is carried out by roebling. (orig.).

  4. PARALLEL COMPOUND METHODS FOR SOLVING PARTITIONED STIFF SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Li-rong Chen; De-gui Liu

    2001-01-01

    This paper deals with the solution of partitioned systems of nonlinear stiff differential equations. Given a differential system, the user may specify some equations to be stiff and others to be nonstiff. For the numerical solution of such a system Parallel Compound Methods(PCMs) are studied. Nonstiff equations are integrated by a parallel explicit RK method while a parallel Rosenbrock method is used for the stiff part of the system. Their order conditions, their convergence and their numerical stability are discussed,and the numerical tests are conducted on a personal computer and a parallel computer.

  5. The Dynamic Stiffness of Surface Footings for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Vahdatirad, Mohammadjavad; Andersen, Lars; Clausen, Johan;

    2011-01-01

    This study concerns the dynamic stiffness of foundations for large offshore wind turbines. Especially, the purpose of the analysis is to quantify the uncertainties related to the first natural frequency of a turbine supported by a surface footing on layered soil. The dynamic properties...... due to sediment transportation. Further, the stiffness and density of the materials within a single layer is subject to uncertainties. This leads to uncertainties of the dynamic stiffness of the foundation and therefore the natural frequencies. The aim of the study is to quantify the level...... of uncertainties and discuss the utilization of reliability-based design of surface footings for wind turbines....

  6. Hormones and arterial stiffness in patients with chronic kidney disease.

    Science.gov (United States)

    Gungor, Ozkan; Kircelli, Fatih; Voroneanu, Luminita; Covic, Adrian; Ok, Ercan

    2013-01-01

    Cardiovascular disease constitutes the major cause of mortality in patients with chronic kidney disease. Arterial stiffness is an important contributor to the occurrence and progression of cardiovascular disease. Various risk factors, including altered hormone levels, have been suggested to be associated with arterial stiffness. Based on the background that chronic kidney disease predisposes individuals to a wide range of hormonal changes, we herein review the available data on the association between arterial stiffness and hormones in patients with chronic kidney disease and summarize the data for the general population.

  7. A novel energy-efficient rotational variable stiffness actuator.

    Science.gov (United States)

    Rao, Shodhan; Carloni, Raffaella; Stramigioli, Stefano

    2011-01-01

    This paper presents the working principle, the design and realization of a novel rotational variable stiffness actuator, whose stiffness can be varied independently of its output angular position. This actuator is energy-efficient, meaning that the stiffness of the actuator can be varied by keeping constant the internal stored energy of the actuator. The principle of the actuator is an extension of the principle of translational energy-efficient actuator vsaUT. A prototype based on the principle has been designed, in which ball-bearings and linear slide guides have been used in order to reduce losses due to friction.

  8. Arterial pressure suffices to increase liver stiffness.

    Science.gov (United States)

    Piecha, Felix; Peccerella, Teresa; Bruckner, Tom; Seitz, Helmut-Karl; Rausch, Vanessa; Mueller, Sebastian

    2016-11-01

    Noninvasive measurement of liver stiffness (LS) has been established to screen for liver fibrosis. Since LS is also elevated in response to pressure-related conditions such as liver congestion, this study was undertaken to learn more about the role of arterial pressure on LS. LS was measured by transient elastography (μFibroscan platform, Echosens, Paris, France) during single intravenous injections of catecholamines in anesthetized rats with and without thioacetamide (TAA)-induced fibrosis. The effect of vasodilating glycerol trinitrate (GTN) on LS was also studied. Pressures in the abdominal aorta and caval and portal veins were measured in real time with the PowerLab device (AD Instruments, Dunedin, New Zealand). Baseline LS values in all rats (3.8 ± 0.5 kPa, n = 25) did not significantly differ from those in humans. Epinephrine and norepinephrine drastically increased mean arterial pressure (MAP) from 82 to 173 and 156 mmHg. Concomitantly, LS almost doubled from 4 to 8 kPa, while central venous pressure remained unchanged. Likewise, portal pressure only showed a slight and delayed increase. In the TAA-induced fibrosis model, LS increased from 9.5 ± 1.0 to 25.6 ± 14.7 kPa upon epinephrine injection and could efficiently be decreased by GTN. We finally show a direct association in humans in a physiological setting of elevated cardiac output and MAP. During continuous spinning at 200 W, MAP increased from 84 ± 8 to 99 ± 11 mmHg while LS significantly increased from 4.4 ± 1.8 to 6.7 ± 2.1 kPa. In conclusion, our data show that arterial pressure suffices to increase LS. Moreover, lowering MAP efficiently decreases LS in fibrotic livers that are predominantly supplied by arterial blood. Copyright © 2016 the American Physiological Society.

  9. Exploring senior nurses' experiences of leading organizational change.

    Science.gov (United States)

    Boyal, Amunpreet; Hewison, Alistair

    2016-01-01

    Purpose - The aim of this paper is to explore Senior nurses' experiences of leading organizational change. There is a substantial literature reporting middle-level nurse managers' experiences of change; however, there is less evidence concerning senior nurses' perspectives. In view of this, interview data collected from senior nurses, as part of a study of major organizational change, were analysed to redress this imbalance. Design/methodology/approach - In-depth semi-structured interviews (n = 14) were conducted with senior nurses (between 2009 and 2012). Findings - Senior nurses' activity centred on leadership and workforce issues, internal influences and external pressures. In periods of change, appropriate leadership was vital, and "weak" leaders were considered to have an adverse effect on teams. Concerns were expressed about financial strictures and their impact on patient care and service provision. The senior nurses were striving to provide the best quality of service delivery with the limited resources available. Concentration on operational matters was necessary to maintain stability in periods of change. However, this prevented senior nurses from influencing strategic decision-making in their organizations. Practical implications - If senior nurses are to realise their potential to operate at a strategic level, they need to be given time and support to lead, rather than just react to change. This research emphasises the importance of a "nursing voice" to inform board-level decisions and maintain a focus on patient care. Originality/value - This research sheds light on the work of a key group of staff in health-care organizations. Understanding senior nurses' experience of and contribution to change is a useful contribution to health services research.

  10. "INTRAOPERATIVE SPINAL STIFFNESS MEASUREMENT IN MANAGEMENT OF SPINAL CANAL STENOSIS "

    Directory of Open Access Journals (Sweden)

    M. Karami

    2005-08-01

    Full Text Available In this study to determine whether spine stiffness is predictive of clinical results after lumbar spinal fusion for spinal stenosis, a total of 78 patients were measured intraoperatively with Kocher clamp manual distraction technique to determine motion segment stiffness then spinal fusion was performed for any loose segment. ‎Statistical analysis revealed that stiffness measurement correlate with clinical results of surgery. During a minimum of 2 years follow up after surgery, patients who had loose motion segment before or after decompression and were fused had the same level of satisfaction with surgical results as patients without loose segments and fusion. ‎We concluded that intraoperative spinal stiffness measurement provide a good indicator to spine fusion after lumbar canal stenosis ‎surgery.

  11. Polyester mooring stiffness modeling for deepwater floating system

    Institute of Scientific and Technical Information of China (English)

    Chen Yongjun; Qu Yan; Zhang Tianyu

    2013-01-01

    Polyester mooring has become increasing popular to serve as permanent station-keeping system for deepwater floating system during recent years.Comparing to the traditional steel wire mooring,polyester mooring provides significant benefits in deepwater,such as reduced installed capital expenditure (CAPEX) and smaller vertical loads on host platform.Polyester rope is a visco-elastic material,and its stiffness is nonlinear and affected by mean load,load range,loading period and loading history.There is a perception that the polyester stiffness model has significant impact on the floating system' s performance.This paper presents a detailed description and comparison of two stiffness models and three analytic approaches,and provides a systematic study of the impact of polyester mooring stiffness modeling on the deepwater floating system performance.

  12. Introduction to the Points Singly Used for Stiff Neck

    Institute of Scientific and Technical Information of China (English)

    李鸿超; 余光辉

    2004-01-01

    @@ In acupuncture treatment of stiff neck, based on the patients' individual conditions, flexible application of different single points can quickly bring about good therapeutic results. The following is a collection of the points singly used for stiffneck.

  13. Torque-stiffness-controlled dynamic walking with central pattern generators.

    Science.gov (United States)

    Huang, Yan; Vanderborght, Bram; Van Ham, Ronald; Wang, Qining

    2014-12-01

    Walking behavior is modulated by controlling joint torques in most existing passivity-based bipeds. Controlled Passive Walking with adaptable stiffness exhibits controllable natural motions and energy efficient gaits. In this paper, we propose torque-stiffness-controlled dynamic bipedal walking, which extends the concept of Controlled Passive Walking by introducing structured control parameters and a bio-inspired control method with central pattern generators. The proposed walking paradigm is beneficial in clarifying the respective effects of the external actuation and the internal natural dynamics. We present a seven-link biped model to validate the presented walking. Effects of joint torque and joint stiffness on gait selection, walking performance and walking pattern transitions are studied in simulations. The work in this paper develops a new solution of motion control of bipedal robots with adaptable stiffness and provides insights of efficient and sophisticated walking gaits of humans.

  14. Identification of dynamic stiffness matrix of bearing joint region

    Institute of Scientific and Technical Information of China (English)

    Feng HU; Bo WU; Youmin HU; Tielin SHI

    2009-01-01

    The paper proposes an identification method of the dynamic stiffness matrix of a bearing joint region on the basis of theoretical analysis and experiments. The author deduces an identification model of the dynamic stiffness matrix from the synthetic substructure method. The dynamic stiffness matrix of the bearing joint region can be identified by measuring the matrix of frequency response function (FRFs) of the substructure (axle) and whole structure (assembly of the axle, bearing, and bearing housing) in different positions. Considering difficulty in measuring angular displacement, applying moment, and directly measuring relevant FRFs of rotational degree of freedom, the author employs an accurately calibrated finite element model of the unconstrained structure for indirect estimation. With experiments and simulation analysis, FRFs related with translational degree of freedom, which is estimated through the finite element model, agrees with experimental results, and there is very high reliability in the identified dynamic stiffness matrix of the bearing joint region.

  15. Axial Dynamic Stiffness of Tubular Piles in Viscoelastic Soil

    DEFF Research Database (Denmark)

    Bayat, Mehdi; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2016-01-01

    -resonance are presented .in series of Bessel's function. Important responses, such as dynamic stiffness and phase angle, are compared for different values of the loss factor as the material damping, Y0W1g's modulus and Poisson's ratio in a viscoelastic soil. Results are verified. with known results reported......, whilst the phase angle is independent of the properties of the soil. It is shown that the non-dimensional dynamic stiffness changes linearly with high-frequency load. The conclusion from the results of this study is that the material properties of soil are significant parameters in the dynamic stiffness...... when the dynamic vertical excitation is applied. The smooth surface along the entire interface is considered. The Betti reciprocal theorem along with Somigliana's identity and Green's function are employed to drive the dynamic stiffness of jacket structures. Modes of the resonance and anti...

  16. Gallstone disease is associated with arterial stiffness progression.

    Science.gov (United States)

    Yu, Kai-Jing; Zhang, Ji-Rong; Li, Ying; Huang, Xiaoyi; Liu, Tiemin; Li, Chuanfu; Wang, Rui-Tao

    2017-01-01

    Gallstones have been linked to dyslipidemia, metabolic syndrome and cardiovascular disease. Arterial stiffness is an indicator of subclinical atherosclerosis. The aim of this study was to prospectively examine the relationship between gallstone disease and arterial stiffness progression in 347 men and 454 women. These subjects were followed for 7 years. Arterial stiffness progression was measured based on increases in brachial-ankle pulse wave velocity. Changes in brachial-ankle pulse wave velocity during the study period were significantly greater in patients with gallstones than in subjects without gallstones. After adjusting for multiple risk factors, gallstone disease was found to be a significant and independent predictor of brachial-ankle pulse wave velocity progression (β=0.189; Pgallstone disease is an independent predictor of arterial stiffness progression, even after adjusting for other cardiovascular risk factors.

  17. Accuracy Improvement for Stiffness Modeling of Parallel Manipulators

    CERN Document Server

    Pashkevich, Anatoly; Chablat, Damien; Wenger, Philippe

    2009-01-01

    The paper focuses on the accuracy improvement of stiffness models for parallel manipulators, which are employed in high-speed precision machining. It is based on the integrated methodology that combines analytical and numerical techniques and deals with multidimensional lumped-parameter models of the links. The latter replace the link flexibility by localized 6-dof virtual springs describing both translational/rotational compliance and the coupling between them. There is presented detailed accuracy analysis of the stiffness identification procedures employed in the commercial CAD systems (including statistical analysis of round-off errors, evaluating the confidence intervals for stiffness matrices). The efficiency of the developed technique is confirmed by application examples, which deal with stiffness analysis of translational parallel manipulators.

  18. Molecular Cues Guiding Matrix Stiffness in Liver Fibrosis

    Science.gov (United States)

    Saneyasu, Takaoki; Akhtar, Riaz

    2016-01-01

    Tissue and matrix stiffness affect cell properties during morphogenesis, cell growth, differentiation, and migration and are altered in the tissue remodeling following injury and the pathological progression. However, detailed molecular mechanisms underlying alterations of stiffness in vivo are still poorly understood. Recent engineering technologies have developed powerful techniques to characterize the mechanical properties of cell and matrix at nanoscale levels. Extracellular matrix (ECM) influences mechanical tension and activation of pathogenic signaling during the development of chronic fibrotic diseases. In this short review, we will focus on the present knowledge of the mechanisms of how ECM stiffness is regulated during the development of liver fibrosis and the molecules involved in ECM stiffness as a potential therapeutic target for liver fibrosis. PMID:27800489

  19. Wing/store flutter with nonlinear pylon stiffness

    Science.gov (United States)

    Desmarais, R. N.; Reed, W. H., III

    1980-01-01

    Recent wind tunnel tests and analytical studies show that a store mounted on a pylon with soft pitch stiffness provides substantial increase in flutter speed of fighter aircraft and reduces dependency of flutter on mass and inertia of the store. This concept, termed the decoupler pylon, utilizes a low frequency control system to maintain pitch alignment of the store during maneuvers and changing flight conditions. Under rapidly changing transient loads, however, the alignment control system may allow the store to momentarily bottom against a relatively stiff backup structure in which case the pylon stiffness acts as a hardening nonlinear spring. Such structural nonlinearities are known to affect not only the flutter speed but also the basic behavior of the instability. The influence of pylon stiffness nonlinearities or the flutter characteristics of wing mounted external stores is examined.

  20. Molecular Cues Guiding Matrix Stiffness in Liver Fibrosis

    Directory of Open Access Journals (Sweden)

    Takaoki Saneyasu

    2016-01-01

    Full Text Available Tissue and matrix stiffness affect cell properties during morphogenesis, cell growth, differentiation, and migration and are altered in the tissue remodeling following injury and the pathological progression. However, detailed molecular mechanisms underlying alterations of stiffness in vivo are still poorly understood. Recent engineering technologies have developed powerful techniques to characterize the mechanical properties of cell and matrix at nanoscale levels. Extracellular matrix (ECM influences mechanical tension and activation of pathogenic signaling during the development of chronic fibrotic diseases. In this short review, we will focus on the present knowledge of the mechanisms of how ECM stiffness is regulated during the development of liver fibrosis and the molecules involved in ECM stiffness as a potential therapeutic target for liver fibrosis.

  1. The measurement of plain weft-knitted fabric stiffness

    Science.gov (United States)

    Haji Mohamad, Ayhan; Cassidy, Thomas; Brydon, Alan; Halley, Dave

    2012-05-01

    A new instrument and a test method are presented in this paper that can evaluate the stiffness of plain weft-knitted fabrics. The WIRA Instrumentation Tester can measure torsion data for various flexible fibre assemblies whilst they are being twisted. The torsional properties of two types of fabrics, namely nonwoven and knitted fabrics, were analyzed. Then, comparisons between bending rigidity and torsional rigidity have been conducted using FAST-2, Shirley, Heart Loop and the new WIRA method for the assessment of fabric stiffness. The results show high correlation between bending rigidity and torsional rigidity in assessment of nonwoven fabric stiffness; they also reveal that the WIRA tester and torsional rigidity are more suitable for characterizing the stiffness of plain weft-knitted fabrics than the other test methods.

  2. A new variable stiffness suspension system: passive case

    Directory of Open Access Journals (Sweden)

    O. M. Anubi

    2013-02-01

    Full Text Available This paper presents the design, analysis, and experimental validation of the passive case of a variable stiffness suspension system. The central concept is based on a recently designed variable stiffness mechanism. It consists of a horizontal control strut and a vertical strut. The main idea is to vary the load transfer ratio by moving the location of the point of attachment of the vertical strut to the car body. This movement is controlled passively using the horizontal strut. The system is analyzed using an L2-gain analysis based on the concept of energy dissipation. The analyses, simulation, and experimental results show that the variable stiffness suspension achieves better performance than the constant stiffness counterpart. The performance criteria used are; ride comfort, characterized by the car body acceleration, suspension deflection, and road holding, characterized by tire deflection.

  3. The memory training by children, adults and seniors

    OpenAIRE

    KASTNEROVÁ, Markéta

    2010-01-01

    The target of the work is to study the memory training by the children, adults and seniors. The work has a theoretical character. It describes the memory development from birth to the senior age, it characterizes the memory and its impairments by the children, adults and seniors. In context of aging process in our population there is a rumour about the memory training by the older age group. But it is necessary to be aware of it, that the memory training is important in every age and the soon...

  4. Cultivation of Intercultural Communicative Competence of Senior High School Students

    Institute of Scientific and Technical Information of China (English)

    苏丹

    2014-01-01

    With the trend of globalization in education and the strengthened position of English as a foreign language in China, the need to understand the cultural differences between Chinese and Western culture is becoming increasingly urgent, especially for the students in senior high schools in China. This paper is aimed to arouse the awareness of the urgency to improve the inter-cultural communication competence of the students in senior high school in China. It proposes four feasible and conducive sug-gestions for senior high schools in China to set up curriculum about Western culture to meet the needs of their students.

  5. Arterial stiffness & Sri Lankan chronic kidney disease of unknown origin

    OpenAIRE

    Fiona Gifford; Robert Kimmitt; Chula Herath; Webb, David J.; Vanessa Melville; Sisira Siribaddana; Michael Eddleston; Neeraj Dhaun

    2016-01-01

    Chronic kidney disease (CKD) is common and independently associated with cardiovascular disease (CVD). Arterial stiffness contributes to CVD risk in CKD. In many developing countries a considerable proportion of CKD remains unexplained, termed CKDu. We assessed arterial stiffness in subjects with Sri Lankan CKDu, in matched controls without CKD and in those with defined CKD. Aortic blood pressure (BP), pulse wave velocity (PWV) and augmentation index (AIx) were assessed in 130 subjects (50 wi...

  6. Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells

    Directory of Open Access Journals (Sweden)

    Jessica L Eisenberg

    2011-01-01

    Full Text Available Jessica L Eisenberg1,2, Asmahan Safi3, Xiaoding Wei3, Horacio D Espinosa3, GR Scott Budinger2, Desire Takawira1, Susan B Hopkinson1, Jonathan CR Jones1,21Department of Cell and Molecular Biology, 2Division of Pulmonary Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; 3Department of Mechanical Engineering, Northwestern University, Evanston, IL, USAAim: The aim of the study was to address whether a stiff substrate, a model for pulmonary fibrosis, is responsible for inducing changes in the phenotype of alveolar epithelial cells (AEC in the lung, including their deposition and organization of extracellular matrix (ECM proteins.Methods: Freshly isolated lung AEC from male Sprague Dawley rats were seeded onto polyacrylamide gel substrates of varying stiffness and analyzed for expression and organization of adhesion, cytoskeletal, differentiation, and ECM components by Western immunoblotting and confocal immunofluorescence microscopy.Results: We observed that substrate stiffness influences cell morphology and the organization of focal adhesions and the actin cytoskeleton. Surprisingly, however, we found that substrate stiffness has no influence on the differentiation of type II into type I AEC, nor does increased substrate stiffness lead to an epithelial–mesenchymal transition. In contrast, our data indicate that substrate stiffness regulates the expression of the α3 laminin subunit by AEC and the organization of both fibronectin and laminin in their ECM.Conclusions: An increase in substrate stiffness leads to enhanced laminin and fibronectin assembly into fibrils, which likely contributes to the disease phenotype in the fibrotic lung.Keywords: alveolar epithelial cells, fibrosis, extracellular matrix, substrate stiffness

  7. Stiffness selection in synthesis of mechatronic discrete systems

    Science.gov (United States)

    Buchacz, Andrzej; Gałęziowski, Damian

    2016-11-01

    In the paper, the known algorithm of designing of mechatronic discrete systems has been decomposed. As a result, detailed analysis of stiffness selection, during the process of distribution of dynamical characteristics functions, has been done. Based on synthesized one degree of freedom system that utilize piezostack actuator, detailed constrains related to the stiffness and their impact for mechanical, dimensionless and mechatronic parameters, have been investigated. The work extends the known problem of vibration control in discrete mechatronic systems

  8. Inflammatory Markers for Arterial Stiffness in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Ioana Mozos

    2017-08-01

    Full Text Available Arterial stiffness predicts an increased risk of cardiovascular events. Inflammation plays a major role in large arteries stiffening, related to atherosclerosis, arteriosclerosis, endothelial dysfunction, smooth muscle cell migration, vascular calcification, increased activity of metalloproteinases, extracellular matrix degradation, oxidative stress, elastolysis, and degradation of collagen. The present paper reviews main mechanisms explaining the crosstalk between inflammation and arterial stiffness and the most common inflammatory markers associated with increased arterial stiffness, considering the most recent clinical and experimental studies. Diverse studies revealed significant correlations between the severity of arterial stiffness and inflammatory markers, such as white blood cell count, neutrophil/lymphocyte ratio, adhesion molecules, fibrinogen, C-reactive protein, cytokines, microRNAs, and cyclooxygenase-2, in patients with a broad variety of diseases, such as metabolic syndrome, diabetes, coronary heart disease, peripheral arterial disease, malignant and rheumatic disorders, polycystic kidney disease, renal transplant, familial Mediterranean fever, and oral infections, and in women with preeclampsia or after menopause. There is strong evidence that inflammation plays an important and, at least, partly reversible role in the development of arterial stiffness, and inflammatory markers may be useful additional tools in the assessment of the cardiovascular risk in clinical practice. Combined assessment of arterial stiffness and inflammatory markers may improve non-invasive assessment of cardiovascular risk, enabling selection of high-risk patients for prophylactic treatment or more regular medical examination. Development of future destiffening therapies may target pro-inflammatory mechanisms.

  9. Non-crossbridge stiffness in active muscle fibres.

    Science.gov (United States)

    Colombini, Barbara; Nocella, Marta; Bagni, Maria Angela

    2016-01-01

    Stretching of an activated skeletal muscle induces a transient tension increase followed by a period during which the tension remains elevated well above the isometric level at an almost constant value. This excess of tension in response to stretching has been called 'static tension' and attributed to an increase in fibre stiffness above the resting value, named 'static stiffness'. This observation was originally made, by our group, in frog intact muscle fibres and has been confirmed more recently, by us, in mammalian intact fibres. Following stimulation, fibre stiffness starts to increase during the latent period well before crossbridge force generation and it is present throughout the whole contraction in both single twitches and tetani. Static stiffness is dependent on sarcomere length in a different way from crossbridge force and is independent of stretching amplitude and velocity. Static stiffness follows a time course which is distinct from that of active force and very similar to the myoplasmic calcium concentration time course. We therefore hypothesize that static stiffness is due to a calcium-dependent stiffening of a non-crossbridge sarcomere structure, such as the titin filament. According to this hypothesis, titin, in addition to its well-recognized role in determining the muscle passive tension, could have a role during muscle activity.

  10. Evaluation of arterial stiffness in nondiabetic chronic kidney disease patients

    Directory of Open Access Journals (Sweden)

    Bodanapu Mastanvalli

    2017-01-01

    Full Text Available Chronic kidney disease (CKD is a growing problem worldwide. Clinical and epidemiologic studies have shown that structural and functional changes that occur in major arteries are a major contributing factor to the high mortality in uremic patients. Recent studies have shown a stepwise increase of the carotid-femoral pulse wave velocity (cfPWV from CKD Stage 1 to Stage 5. We evaluated the cfPWV and augmentation index (AIx, as indirect markers of arterial stiffness in patients with nondiabetic CKD and compared the values with normal population; we also evaluated the relationship between various stages of CKD and arterial stiffness markers. This cross-sectional study was carried out in the Department of Nephrology for a duration of two years from January 15, 2012, to January 14, 2014. Fifty patients with nondiabetic CKD were studied along with 50 healthy volunteers who did not have CKD, who served as controls. Assessment of arterial stiffness (blood pressure, PWV, heart rate, aortic augmentation pressure, and AIx was performed using the PeriScope device. PWV positively correlated with systolic and diastolic blood pressure, mean aortic arterial pressure, serum creatinine, and serum uric acid and negatively correlated with estimated glomerular filtration rate. Arterial stiffness increased as CKD stage increased and was higher in nondiabetic CKD group than in the general population. Arterial stiffness progressed gradually from CKD Stage 2 to 5, and then abruptly, in dialysis patients. Measures to decrease the arterial stiffness and its influence on decreasing cardiovascular events need further evaluation.

  11. A multiwell platform for studying stiffness-dependent cell biology.

    Directory of Open Access Journals (Sweden)

    Justin D Mih

    Full Text Available Adherent cells are typically cultured on rigid substrates that are orders of magnitude stiffer than their tissue of origin. Here, we describe a method to rapidly fabricate 96 and 384 well platforms for routine screening of cells in tissue-relevant stiffness contexts. Briefly, polyacrylamide (PA hydrogels are cast in glass-bottom plates, functionalized with collagen, and sterilized for cell culture. The Young's modulus of each substrate can be specified from 0.3 to 55 kPa, with collagen surface density held constant over the stiffness range. Using automated fluorescence microscopy, we captured the morphological variations of 7 cell types cultured across a physiological range of stiffness within a 384 well plate. We performed assays of cell number, proliferation, and apoptosis in 96 wells and resolved distinct profiles of cell growth as a function of stiffness among primary and immortalized cell lines. We found that the stiffness-dependent growth of normal human lung fibroblasts is largely invariant with collagen density, and that differences in their accumulation are amplified by increasing serum concentration. Further, we performed a screen of 18 bioactive small molecules and identified compounds with enhanced or reduced effects on soft versus rigid substrates, including blebbistatin, which abolished the suppression of lung fibroblast growth at 1 kPa. The ability to deploy PA gels in multiwell plates for high throughput analysis of cells in tissue-relevant environments opens new opportunities for the discovery of cellular responses that operate in specific stiffness regimes.

  12. Rotational and peak torque stiffness of rugby shoes.

    Science.gov (United States)

    Ballal, Moez S; Usuelli, Federico Giuseppe; Montrasio, Umberto Alfieri; Molloy, Andy; La Barbera, Luigi; Villa, Tomaso; Banfi, Giuseppe

    2014-09-01

    Sports people always strive to avoid injury. Sports shoe designs in many sports have been shown to affect traction and injury rates. The aim of this study is to demonstrate the differing stiffness and torque in rugby boots that are designed for the same effect. Five different types of rugby shoes commonly worn by scrum forwards were laboratory tested for rotational stiffness and peak torque on a natural playing surface generating force patterns that would be consistent with a rugby scrum. The overall internal rotation peak torque was 57.75±6.26 Nm while that of external rotation was 56.55±4.36 Nm. The Peak internal and external rotational stiffness were 0.696±0.1 and 0.708±0.06 Nm/deg respectively. Our results, when compared to rotational stiffness and peak torques of football shoes published in the literature, show that shoes worn by rugby players exert higher rotational and peak torque stiffness compared to football shoes when tested on the same natural surfaces. There was significant difference between the tested rugby shoes brands. In our opinion, to maximize potential performance and lower the potential of non-contact injury, care should be taken in choosing boots with stiffness appropriate to the players main playing role. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Leg stiffness of sprinters using running-specific prostheses

    Science.gov (United States)

    McGowan, Craig P.; Grabowski, Alena M.; McDermott, William J.; Herr, Hugh M.; Kram, Rodger

    2012-01-01

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring–mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of unilateral amputees and both ALs of bilateral amputees compared with the bioL of non-amputees for nearly every variable measured. Leg stiffness remained constant or increased with speed in bioL, but decreased with speed in legs with RSPs. The decrease in leg stiffness in legs with RSPs was mainly owing to a combination of lower peak ground reaction forces and increased leg compression with increasing speeds. Leg stiffness is an important parameter affecting contact time and the force exerted on the ground. It is likely that the fixed stiffness of the prosthesis coupled with differences in the limb posture required to run with the prosthesis limits the ability to modulate whole leg stiffness and the ability to apply high vertical ground reaction forces during sprinting. PMID:22337629

  14. Sex Differences in Limb and Joint Stiffness in Recreational Runners

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2015-09-01

    Full Text Available Purpose. Female runners are known to be at greater risk from chronic running injuries than age-matched males, although the exact mechanisms are often poorly understood. The aim of the current investigation was to determine if female recreational runners exhibit distinct limb and joint stiffness characteristics in relation to their male counterparts. Methods. Fourteen male and fourteen female runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system operating at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. All stiffness and joint moment parameters were normalized to body mass. Sex differences in normalized limb and knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that normalized limb (male = 0.18 ± 0.07, female = 0.37 ± 0.10 kN · kg · m-1 and knee stiffness (male = 5.59 ± 2.02, female = 7.34 ± 1.78 Nm · kg · rad-1 were significantly greater in female runners. Conclusions. On the basis that normalized knee and limb stiffness were shown to be significantly greater in female runners, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between sexes.

  15. Stiffness mapping prostate biopsy samples using a tactile sensor.

    Science.gov (United States)

    Peng, Qiyu; Omata, Sadao; Peehl, Donna M; Constantinou, Chris E

    2011-01-01

    Previous studies have demonstrated that the stiffness of cancerous cells reflects their pathological stage and progression rates, with increased cancerous cell stiffness associated with increased aggressiveness. Therefore, the elasticity of the cancerous cells has the potential to be used as an indicator of the cancer's aggressiveness. However, the sensitivity and resolution of current palpation and imaging techniques are not sufficient to detect small cancerous tissues. In previous studies, we developed a tactile-based device to map with high resolution the stiffness of a tissue section. The purpose of this study is to evaluate this device using different tissues (BPH, Cancer and PZ) collected from human prostates. The preliminary results show that the tactile device is sensitive enough to tell the differences of the stiffness of different tissues. The results also disclosed the factors (humidity, temperature and tissue degradation) which could dramatically affect the results of stiffness mapping. The tactile technology described in this paper has the potential to help disclose the underlying mechanical mechanisms that lead to increased stiffness in prostate tumors.

  16. Direct measurement of human ankle stiffness during quiet standing: the intrinsic mechanical stiffness is insufficient for stability.

    Science.gov (United States)

    Loram, Ian D; Lakie, Martin

    2002-12-15

    During quiet standing the human "inverted pendulum" sways irregularly. In previous work where subjects balanced a real inverted pendulum, we investigated what contribution the intrinsic mechanical ankle stiffness makes to achieve stability. Using the results of a plausible model, we suggested that intrinsic ankle stiffness is inadequate for providing stability. Here, using a piezo-electric translator we applied small, unobtrusive mechanical perturbations to the foot while the subject was standing freely. These short duration perturbations had a similar size and velocity to movements which occur naturally during quiet standing, and they produced no evidence of any stretch reflex response in soleus, or gastrocnemius. Direct measurement confirms our earlier conclusion; intrinsic ankle stiffness is not quite sufficient to stabilise the body or pendulum. On average the directly determined intrinsic stiffness is 91 +/- 23 % (mean +/- S.D.) of that necessary to provide minimal stabilisation. The stiffness was substantially constant, increasing only slightly with ankle torque. This stiffness cannot be neurally regulated in quiet standing. Thus we attribute this stiffness to the foot, Achilles' tendon and aponeurosis rather than the activated calf muscle fibres. Our measurements suggest that the triceps surae muscles maintain balance via a spring-like element which is itself too compliant to guarantee stability. The implication is that the brain cannot set ankle stiffness and then ignore the control task because additional modulation of torque is required to maintain balance. We suggest that the triceps surae muscles maintain balance by predictively controlling the proximal offset of the spring-like element in a ballistic-like manner.

  17. Stem Cells Hold Promise, Peril in Treating Seniors' Eye Disease

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_164099.html Stem Cells Hold Promise, Peril in Treating Seniors' Eye Disease ... 15, 2017 WEDNESDAY, March 15, 2017 (HealthDay News) -- Stem cells may offer new hope for people losing their ...

  18. 77 FR 44313 - 2011 Career Reserved Senior Executive Positions

    Science.gov (United States)

    2012-07-27

    ... Coordination Office. Senior Information Technology Policy Advisor. Director, Smart Grid and Cyber-Physical..., Financial Systems Planning and Management. Associate Chief Financial Officer for Financial Policy and... Programs. Deputy Administrator for Natural Resources and Sustainable Agriculture Systems. Beltsville Area...

  19. 75 FR 62591 - Performance Review Board, Senior Executive Service (SES)

    Science.gov (United States)

    2010-10-12

    ... Diversity and Equal Opportunity, NASA Headquarters; Assistant Administrator for Human Capital Management..., Dryden Flight Research Center; Director, Glenn Research Center ; Director, Goddard Space Flight Center..., Marshall Space Flight Center; Director, Stennis Space Center. Senior Executive Committee Chairperson...

  20. 75 FR 67399 - Performance Review Board, Senior Executive Service (SES)

    Science.gov (United States)

    2010-11-02

    ... Human Capital Management, NASA Headquarters Associate Administrator for Independent Program and Cost... Flight Research Center Director, Glenn Research Center Director, Goddard Space Flight Center Director... Space Flight Center Director, Stennis Space Center Senior Executive Committee Chairperson, Deputy...

  1. Configuration interaction wave functions: A seniority number approach

    Energy Technology Data Exchange (ETDEWEB)

    Alcoba, Diego R. [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Torre, Alicia; Lain, Luis, E-mail: qfplapel@lg.ehu.es [Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, E-48080 Bilbao (Spain); Massaccesi, Gustavo E. [Departamento de Ciencias Exactas, Ciclo Básico Común, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Oña, Ofelia B. [Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata (Argentina)

    2014-06-21

    This work deals with the configuration interaction method when an N-electron Hamiltonian is projected on Slater determinants which are classified according to their seniority number values. We study the spin features of the wave functions and the size of the matrices required to formulate states of any spin symmetry within this treatment. Correlation energies associated with the wave functions arising from the seniority-based configuration interaction procedure are determined for three types of molecular orbital basis: canonical molecular orbitals, natural orbitals, and the orbitals resulting from minimizing the expectation value of the N-electron seniority number operator. The performance of these bases is analyzed by means of numerical results obtained from selected N-electron systems of several spin symmetries. The comparison of the results highlights the efficiency of the molecular orbital basis which minimizes the mean value of the seniority number for a state, yielding energy values closer to those provided by the full configuration interaction procedure.

  2. Exercise Not Making Dent in Most Seniors' Down Time

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_167481.html Exercise Not Making Dent in Most Seniors' Down Time ... 2017 FRIDAY, July 28, 2017 (HealthDay News) -- Regular exercise does little to reduce the amount of time ...

  3. Senior Years May Truly Be Golden for Happiness

    Science.gov (United States)

    ... html Senior Years May Truly Be Golden for Happiness Researchers find people get less stressed and are ... only a small difference in our capacity for happiness. Genes play a bigger role. Put simply, Maddux ...

  4. 77 FR 65685 - Senior Executive Service Performance Review Board; Membership

    Science.gov (United States)

    2012-10-30

    .... Higginbotham, Director, Executive Resources Division, 3606A, Office of Human Resources, Office of... initial appraisal of a senior executive's performance by the supervisor, along with any recommendations to...), Director, Executive Resources Division, Office of Human Resources, Office of Administration and...

  5. Foreign language education to seniors through intergenerational programmes

    Directory of Open Access Journals (Sweden)

    Határ Ctibor

    2017-01-01

    Full Text Available The intergenerational learning within various types of social environment and in relation to different target groups has long covered a wide range of uses. The professional literature mostly describes its benefits for children and young people, however, the intergenerational education also contributes to the development of personality and the saturation of the educational and psycho-social needs of both adults and seniors. The paper represents the authors’ output of the VEGA research project No. 1/0176/15 and it is structured into three chapters. In the first chapter, the author deals with the opportunities of the foreign language education for (not only disabled seniors. The second chapter focuses on the intergenerational programmes that can be used in the language education of (not only disabled seniors who are clients of social residential facilities. In the third chapter, the author elaborates the psychological aspects of the foreign language education of seniors.

  6. Chances of Successful CPR Dwindle as Seniors Age

    Science.gov (United States)

    ... gov/news/fullstory_165865.html Chances of Successful CPR Dwindle as Seniors Age Study finds fewer older ... new study finds that older Americans have little CPR training, and they are less likely to get ...

  7. Mobilizing Senior Citizens in Co-design Work

    DEFF Research Database (Denmark)

    Malmborg, Lone; Werner, Katharina; Gronvall, Erik;

    2015-01-01

    This paper addresses methodological considerations of participation in design for ageing. Based on the notions of design culture, communities of everyday practice and situated elderliness we present accounts from two settings and discuss methodological issues related to mobilizing senior citizens...

  8. Training Senior Citizen Centers Staff in Blind Rehabilitation Techniques.

    Science.gov (United States)

    Asch, Celine

    1980-01-01

    The author discusses a project conducted in 1979 in which personnel from Arkansas Enterprises for the Blind trained staff members from community based programs for the elderly in techniques designed to involve and assist visually impaired senior citizens. (Author)

  9. Domestic violence in the context of the education of seniors

    Directory of Open Access Journals (Sweden)

    KATEŘINA ŠMEJKALOVÁ

    2016-06-01

    Full Text Available The article discusses domestic violence as dangerous, unlawful and violent conduct, which currently threatens a generation of seniors. The author stresses the need for primary prevention of domestic violence in the context of the education of seniors, at the University of the Third Age. In the text we present the content focus of preventative lectures to the target group of seniors. In connection with the content of primary prevention is highlighted to the opportunity to help the victims of domestic violence through the association for assistance to victims of crime „Bílý kruh bezpečí“. On the basis of the exploratory investigation, in the text there where presented the views at the seniors on the issue of the domestic violence

  10. Protein At All 3 Meals May Help Preserve Seniors' Strength

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_167595.html Protein at All 3 Meals May Help Preserve Seniors' ... 2017 THURSDAY, Aug. 3, 2017 (HealthDay News) -- Eating protein at all three daily meals, instead of just ...

  11. 1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists

    Energy Technology Data Exchange (ETDEWEB)

    Paul H. Wine

    1998-11-23

    DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry

  12. PSI for Low-Enrollment Junior-Senior Physics Courses

    Science.gov (United States)

    Frahm, Charles P.; Young, Robert D.

    1976-01-01

    The administration of a Personalized System of Instruction (PSI) for junior-senior level courses in mechanics, electricity and magneturn, atomic physics, mathematical physics, physics and computers, astrophysics, and relativity is described. (CP)

  13. Foundations in the South African senior phase curriculum for ...

    African Journals Online (AJOL)

    Foundations in the South African senior phase curriculum for entrepreneurship education in consumer studies. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... A qualitative curriculum content analysis was undertaken to investigate the ...

  14. Information sources for decision making by senior managers in two ...

    African Journals Online (AJOL)

    Information sources for decision making by senior managers in two Federal ... Information is widely believed as the raw materials upon which decisions are ... Simple random sampling technique was used to select the population for the study.

  15. Exposure of Senior School Students to Practical Work in Agriculture ...

    African Journals Online (AJOL)

    Exposure of Senior School Students to Practical Work in Agriculture in Ikwerre and ... It was concluded that Teachers adoption Learner-Centred rather than lecture ... that teachers will have enough time to attend to Practical Agricultural lessons.

  16. 77 FR 36491 - Request for Information Regarding Senior Financial Exploitation

    Science.gov (United States)

    2012-06-19

    ... conducting research to identify best practices for educating seniors on personal finance management. The.... Financial Literacy Efforts 6. What financial education, counseling, or personal finance management programs..., practical information on personal finance management? Possible comments could address methods for...

  17. COMS Day as a Communication Senior Capstone Team Project

    Science.gov (United States)

    Ozley, Raymond R.; Wang, Tiffany R.; Ford, Sherry Greenwood; Hardig, Sally Bennett

    2017-01-01

    Courses: Senior Seminar. Objectives: (1) To provide graduating students a semester-long capstone experience where they can apply communication theories/skills in a professional context. (2) To create a capstone project that contributes to programmatic assessment.

  18. This Combo Workout May Suit Obese Seniors Best

    Science.gov (United States)

    ... html This Combo Workout May Suit Obese Seniors Best Aerobic-plus-resistance regimen boosts bone and muscles, ... or none at all, the researchers found. "The best way to improve functional status and reverse frailty ...

  19. Exercise Can Keep Obese Seniors on The Go

    Science.gov (United States)

    ... html Exercise Can Keep Obese Seniors on the Go Study ties physical activity to ability to perform ... neighborhood or to walk several street blocks to go to a store," Kritchevsky said in a medical ...

  20. The Knowledge of HIV/AIDS among Senior Secondary School ...

    African Journals Online (AJOL)

    The Knowledge of HIV/AIDS among Senior Secondary School Students in a Local ... Journal of Community Medicine and Primary Health Care ... There is need for more research to update knowledge and information on adolescent health ...

  1. Misconceptions of Concepts in Chemistry among Senior Secondary ...

    African Journals Online (AJOL)

    Misconceptions of Concepts in Chemistry among Senior Secondary School ... and nomenclature of carbon compounds, natural products, chemistry in industry, ... Research data were collected using 60-item multiple choice tests of the concepts ...

  2. [Strategy for educating senior dermatological residents in mycology].

    Science.gov (United States)

    Mochizuki, Takashi; Tsuboi, Ryoji; Sei, Yoshihiro; Hiruma, Masataro; Watanabe, Shinichi; Makimura, Koichi

    2012-01-01

    To improve the ability of dermatologists to diagnose cutaneous mycoses, we have proposed a list of the minimum mycological knowledge and skills required by senior residents of dermatology. The list includes ability to select the most appropriate sampling method, knowledge of the basic method of potassium hydroxide (KOH) examination and skill in performing fungal cultures and identifying the most prevalent fungal species isolated from skin lesions. It is not possible for the Japanese Society of Medical Mycology to train every senior resident directly, and it is difficult for them to acquire sufficient expertise independently. Consequently, training and advice given by instructors in residents' home institutes is essential. A project of an advanced course for instructors, who are in charge of educating senior residents in their own institute, may be possible. Therefore, we have proposed here a list for instructors of the knowledge and skills required to educate senior residents. Employing this list should realize improved skill in dermatologists.

  3. 76 FR 55677 - Senior Executive Service (SES) Performance Review Board

    Science.gov (United States)

    2011-09-08

    ... objectivity in the performance appraisal process. DATES: Effective September 8, 2011. FOR FURTHER INFORMATION... on the performance appraisal ratings and performance awards for the SES employees. The following have... ADMINISTRATION Senior Executive Service (SES) Performance Review Board AGENCY: General Services...

  4. Institutional Entrepreneurs and Social Innovation in Danish Senior Care

    DEFF Research Database (Denmark)

    Jensen, Per Harboesgaard; Fersch, Barbara

    2017-01-01

    This article discusses the social, political, and administrative dynamics behind shifting welfare policies and social innovations in the senior care provided by Danish municipalities. The main argument is that institutional entrepreneurs are key agents of change and that institutional...

  5. Healthy Family 2009: 8 Great "Whys" Seniors Should Exercise

    Science.gov (United States)

    ... Current Issue Past Issues Healthy Family 2009 8 Great "Whys" Seniors Should Exercise Past Issues / Winter 2009 ... strength—carry groceries, climb stairs Improve balance—prevent falls Restore flexibility—speed recovery from injury Build endurance— ...

  6. Mobilizing Senior Citizens in Co-Design of Mobile Technology

    DEFF Research Database (Denmark)

    Malmborg, Lone; Gronvall, Erik; Messeter, Jörn

    2016-01-01

    &Take project. Challenges for mobilization are identified, based on an analysis of attitudes and values among design researchers and senior citizens. This analysis lead us to identify and discuss three strategies for mobilizing senior citizens in co-design of mobile technology: 1) Understanding being ‘elderly......This paper disseminates work from the European Give&Take project, which aims at co-designing service sharing among senior citizens based on a mobile and distributed platform. With this project as a frame, our paper addresses methodological considerations of participation in co-design for ageing....... Based on the notions of design culture, communities of everyday practice and situated elderliness we present accounts from two European countries, and discuss methodological issues related to mobilizing senior citizens in co-design work as they have manifested themselves and influenced the Give...

  7. 77 FR 70192 - Appointments to Performance Review Boards for Senior Executive Service

    Science.gov (United States)

    2012-11-23

    ... performance appraisal ratings and performance awards for Senior Executives and Senior Level employees: R.W... COMMISSION Appointments to Performance Review Boards for Senior Executive Service AGENCY: Nuclear Regulatory Commission. ACTION: Appointment to Performance Review Boards for Senior Executive Service. SUMMARY: The...

  8. 76 FR 66332 - Appointments to Performance Review Boards for Senior Executive Service

    Science.gov (United States)

    2011-10-26

    ... performance appraisal ratings and performance awards for Senior Executives and Senior Level employees: Darren... COMMISSION Appointments to Performance Review Boards for Senior Executive Service AGENCY: U.S. Nuclear Regulatory Commission. ACTION: Appointment to Performance Review Boards for Senior Executive Service....

  9. The Strategies of Teaching Seniors English through English

    Institute of Scientific and Technical Information of China (English)

    刘丽平

    2009-01-01

    English is widely taught as a foreign language in China. However, the current situation of English teaching cannot keep pace with the requirements of the Senior High School Standards. Some English teachers still insist on the teacher-centered teaching methods. The result is that there is less target language (TL) input and TL output in class. This paper, based on practical teaching theories, attempts to look at some strategies of Senior English classroom instruction.

  10. The Necessity of English Oral Test in Senior Middle School

    Institute of Scientific and Technical Information of China (English)

    雷桂林; 杨峰

    2014-01-01

    One of the reasons that senior school students are discouraged and neither motivated to speak English is that English test in senior middle school involves only written works and there’s no evaluation to speaking communicative competence. In order to improve students’ English speaking ability, English oral test should be added into English test. This paper focuses on its necessity from different aspects such as social need, students’ development,and requirements of the syllabus and curriculum standards and so on.

  11. Generalized seniority and E 2 transitions in the tin isotopes

    Science.gov (United States)

    Morales, Irving O.; Van Isacker, P.; Talmi, I.

    2011-09-01

    Recently, a shallow minimum was discovered in B(E2) values in even Sn isotopes around the middle of the neutron major shell. A peak in that region was expected according to calculations using generalized seniority. In a model calculation we show that the observed shape is consistent with generalized seniority. It seems to be due to the order of filling of j-orbits.

  12. Meal ingestion markedly increases liver stiffness suggesting the need for liver stiffness determination in fasting conditions.

    Science.gov (United States)

    Alvarez, Daniel; Orozco, Federico; Mella, José María; Anders, Maria; Antinucci, Florencia; Mastai, Ricardo

    2015-01-01

    The introduction of noninvasive liver stiffness (LS) determination has heralded a new stage in the diagnosis and treatment of liver fibrosis. We evaluated the effect of food intake on LS in patients with different degrees of liver disease. We evaluated 24 patients (F≤1, n=11 and F> 1, n=13). LS (Fibroscan®) and portal blood flow (PBF) (Doppler ultrasound) were studied before and 30min after ingestion of a standard liquid meal. Food intake increased PBF (51±10%, p1). Hemodynamic and LS values returned to baseline pre-meal levels within 2hours. LS increases markedly after ingestion of a standard meal, irrespective of the degree of fibrosis. Our results strongly suggest that LS should be measured in fasting conditions. Copyright © 2015 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.

  13. Effectiveness of health and wellness initiatives for seniors.

    Science.gov (United States)

    Coberley, Carter; Rula, Elizabeth Y; Pope, James E

    2011-02-01

    Given the increasing prevalence of obesity and lifestyle-related chronic diseases in the United States and abroad, senior wellness initiatives have emerged as a means to stem the troubling trends that threaten the well-being and the economy of many nations. Seniors are an important demographic for such programs because this age group is growing, both as a proportion of the overall population and as a contributor to health care cost escalation. The goal of senior wellness programs is to improve the overall health of seniors through a variety of approaches, including increased physical activity, better nutrition, smoking cessation, and support of other healthy behaviors. Outcome metrics of particular interest are the effects of participation in these programs on health care utilization and expenditures. This review describes several studies that demonstrate reduced inpatient admissions and health care costs, as well as improved health-related quality of life as a direct result of participation in large-scale senior wellness programs. Programs that effectively engage seniors in, and change behavior as a direct result of, participation provide strong evidence that health improvements and decreased health care expenditures can be achieved. However, solutions to the challenges of broader enrollment and sustained participation in these programs would increase the impact of their outcomes and health-related benefits.

  14. Factors Influencing Advancement of Women Senior Leaders in Aerospace Companies

    Science.gov (United States)

    Garrett-Howard, Camille Elaine

    The problem researched in this study was the limited number of women in senior leadership positions in the aerospace industry. The purpose of this qualitative phenomenological research study was to interview women senior leaders in the aerospace industry to explore the factors they perceived as beneficial to their advancement to senior leadership positions in the aerospace industry. The research study was guided by a central research question relating to what professional and personal factors might have led to promotional opportunities into senior leadership roles. Transformational leadership was the conceptual framework used to inform the study. The qualitative, phenomenological approach was selected to gain insights of the lived experiences and perceptions relating to career advancement of women to senior leadership positions in the aerospace industry. Data were collected using a modified Van Kaam method, coded, and analyzed to discern themes or patterns. Findings were that the attributes participants contributed to their success, included a focus on leadership, personal development, and the importance of mentoring relationships. This study presented a positive direction in addressing the gaps in the body of knowledge related to women and leadership development by exploring the experiences of women in senior leadership positions in the aerospace industry. Implications for social change include informing organizations and women about specific leadership development practices as one way to promote more women into leadership positions thus reducing the gap between the number of men and women leaders.

  15. Negotiating candidacy: ethnic minority seniors' access to care.

    Science.gov (United States)

    Koehn, Sharon

    2009-05-01

    The 'Barriers to Access to Care for Ethnic Minority Seniors ' (BACEMS) study in Vancouver, British Columbia, found that immigrant families torn between changing values and the economic realities that accompany immigration cannot always provide optimal care for their elders. Ethnic minority seniors further identified language barriers, immigration status, and limited awareness of the roles of the health authority and of specific service providers as barriers to health care. The configuration and delivery of health services, and health-care providers' limited knowledge of the seniors' needs and confounded these problems. To explore the barriers to access, the BACEMS study relied primarily on focus group data collected from ethnic minority seniors and their families and from health and multicultural service providers. The applicability of the recently developed model of 'candidacy', which emphasises the dynamic, multi-dimensional and contingent character of health-care access to ethnic minority seniors, was assessed. The candidacy framework increased sensitivity to ethnic minority seniors' issues and enabled organisation of the data into manageable conceptual units, which facilitated translation into recommendations for action, and revealed gaps that pose questions for future research. It has the potential to make Canadian research on the topic more co-ordinated.

  16. Human plantarflexor stiffness to multiple single-stretch trials.

    Science.gov (United States)

    Blanpied, P; Smidt, G L

    1992-01-01

    The purpose of this investigation was to determine the influence of different stretch velocities, different rates of pre-stretch force development, and different pre-stretch muscle lengths on the intrinsic stiffness exhibited by the quasi-statically contracting active human plantarflexors during multiple single-stretch trials at 20-60% of maximum isometric contraction. Subjects were positioned prone, with the knee flexed 1.57 rad(90 degrees), shank stabilized, and foot secured in a hard plastic orthotic. Slowly increasing isometric plantarflexion force was produced until the plantarflexors were stretched by a rapid 0.2 rad (12 degrees) dorsiflexion movement. Plantarflexion forces and ankle positions were determined during these stretches as well as during resting stretches when the muscle was inactive. Resting forces were subtracted from the active trials, forces converted to torques, and stiffnesses determined for the first 62 ms of the stretch. The slope of the stiffness vs pre-stretch torque relationship averaged 4.30 +/- 0.34 Nm rad-1 Nm-1. Little difference was found between stiffness determined through the single-stretch method and the results of previous studies employing different mechanical inputs. Differences in stiffnesses with different stretching velocities were caused by computational artifact rather than by differences in intrinsic muscular reaction. Faster rates of pre-stretch force increase prior to the stretch resulted in slightly lower stiffnesses. Different pre-stretch muscle lengths apparently did not result in different stiffnesses. The shape of the torque vs displacement curve was remarkably insensitive to the planned manipulations of the testing conditions, responding in a stereotypical manner.

  17. Substrate stiffness regulates filopodial activities in lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Yu-Ren Liou

    Full Text Available Microenvironment stiffening plays a crucial role in tumorigenesis. While filopodia are generally thought to be one of the cellular mechanosensors for probing environmental stiffness, the effects of environmental stiffness on filopodial activities of cancer cells remain unclear. In this work, we investigated the filopodial activities of human lung adenocarcinoma cells CL1-5 cultured on substrates of tunable stiffness using a novel platform. The platform consists of an optical system called structured illumination nano-profilometry, which allows time-lapsed visualization of filopodial activities without fluorescence labeling. The culturing substrates were composed of polyvinyl chloride mixed with an environmentally friendly plasticizer to yield Young's modulus ranging from 20 to 60 kPa. Cell viability studies showed that the viability of cells cultured on the substrates was similar to those cultured on commonly used elastomers such as polydimethylsiloxane. Time-lapsed live cell images were acquired and the filopodial activities in response to substrates with varying degrees of stiffness were analyzed. Statistical analyses revealed that lung cancer cells cultured on softer substrates appeared to have longer filopodia, higher filopodial densities with respect to the cellular perimeter, and slower filopodial retraction rates. Nonetheless, the temporal analysis of filopodial activities revealed that whether a filopodium decides to extend or retract is purely a stochastic process without dependency on substrate stiffness. The discrepancy of the filopodial activities between lung cancer cells cultured on substrates with different degrees of stiffness vanished when the myosin II activities were inhibited by treating the cells with blebbistatin, which suggests that the filopodial activities are closely modulated by the adhesion strength of the cells. Our data quantitatively relate filopodial activities of lung cancer cells with environmental stiffness and

  18. On improving senior students’speaking ability

    Institute of Scientific and Technical Information of China (English)

    马俊海

    2015-01-01

    With the opening-up of China,English teaching has been getting more and more attention.People are enthusiastic about learning English.As a result,English teaching and reform are coming to a turning point,which predicts a bright future in English education in China.Now,a 9-year voluntary education program is put forward in China.A Standard English course is being used to replace the former teaching outline.The new standard adopts the international system according to which English language education is divided into 9 levels.This has changed the old style of teaching,which attaches importance to grammar and vocabulary.Adopting the new standard helps to develop the senior students’ability to use English in their daily life,by focusing on arousing their interest,and encouraging their participation. The new method will place less stress on“reading and writing”,in favor of“listening”and“speaking”.So now,speaking is getting more and more important in middle high school English teaching. This paper discuss how to improve students’speaking ability and expound the theme through three aspects as follows:⒈The importance of speaking.⒉Some barriers in the process of speaking communication.⒊Essential methods for improving students’speaking ability. The issue will be discussed from the perspective of a teacher of English in junior middle school and a possible conclusion will bereached with the help of some theoretical and practical support.

  19. 油膜刚度变化对转子刚度的影响%Oil Loyer Stiffness Change Affect On Rotale Stiffness

    Institute of Scientific and Technical Information of China (English)

    叶荣学; 孙伟

    2013-01-01

    In this paper,analyzed oil layer thick change affect oil layer stiffness,oil layer stiffness change affect rotate stiffness,relate stiffness change affect vibpation amplitude.%分析了油膜厚度变化对油膜刚度的影响、油膜刚度变化对转子刚度的影响、转子刚度变化对振幅的影响.

  20. Stiffness Analysis of Corrugated Flexure Beam Used in Compliant Mechanisms

    Institute of Scientific and Technical Information of China (English)

    WANG Nianfeng; LIANG Xiaohe; ZHANG Xianmin

    2015-01-01

    Conventional flexible joints generally have limited range of motion and high stress concentration. To overcome these shortcomings, corrugated flexure beam(CF beam) is designed because of its large flexibility obtained from longer overall length on the same span. The successful design of compliant mechanisms using CF beam requires manipulation of the stiffnesses as the design variables. Empirical equations of the CF beam stiffness components, except of the torsional stiffness, are obtained by curve-fitting method. The application ranges of all the parameters in each empirical equation are also discussed. The ratio of off-axis to axial stiffness is considered as a key characteristic of an effective compliant joint. And parameter study shows that the radius of semi-circular segment and the length of straight segment contribute most to the ratio. At last, CF beam is used to design translational and rotational flexible joints, which also verifies the validity of the empirical equations. CF beam with large flexibility is presented, and empirical equations of its stiffness are proposed to facilitate the design of flexible joint with large range of motion.

  1. Dynamic stiffness for thin-walled structures by power series

    Institute of Scientific and Technical Information of China (English)

    ZHU Bin; LEUNG A.Y.T.

    2006-01-01

    The dynamic stiffness method is introduced to analyze thin-walled structures including thin-walled straight beams and spatial twisted helix beam. A dynamic stiffness matrix is formed by using frequency dependent shape functions which are exact solutions of the governing differential equations. With the obtained thin-walled beam dynamic stiffness matrices, the thin-walled frame dynamic stiffness matrix can also be formulated by satisfying the required displacements compatibility and forces equilibrium, a method which is similar to the finite element method (FEM). Then the thin-walled structure natural frequencies can be found by equating the determinant of the system dynamic stiffness matrix to zero. By this way, just one element and several elements can exactly predict many modes of a thin-walled beam and a spatial thin-walled frame, respectively. Several cases are studied and the results are compared with the existing solutions of other methods. The natural frequencies and buckling loads of these thin-walled structures are computed.

  2. Dynamically tuned magnetostrictive spring with electrically controlled stiffness

    Science.gov (United States)

    Scheidler, Justin J.; Asnani, Vivake M.; Dapino, Marcelo J.

    2016-03-01

    This paper presents the design and testing of an electrically controllable magnetostrictive spring that has a dynamically tunable stiffness (i.e., a magnetostrictive Varispring). The device enables in situ stiffness tuning or stiffness switching for vibration control applications. Using a nonlinear electromechanical transducer model and an analytical solution of linear, mechanically induced magnetic diffusion, Terfenol-D is shown to have a faster rise time to stepped voltage inputs and a significantly higher magnetic diffusion cut-off frequency relative to Galfenol. A Varispring is manufactured using a laminated Terfenol-D rod. Further rise time reductions are achieved by minimizing the rod’s diameter and winding the electromagnet with larger wire. Dynamic tuning of the Varispring’s stiffness is investigated by measuring the Terfenol-D rod’s strain response to dynamic, compressive, axial forces in the presence of sinusoidal or square wave control currents. The Varispring’s rise time is \\lt 1 ms for 1 A current switches. Continuous modulus changes up to 21.9 GPa and 500 Hz and square wave modulus changes (dynamic {{Δ }}E effect) up to 12.3 GPa and 100 Hz are observed. Stiffness tunability and tuning bandwidth can be considerably increased by operating about a more optimal bias stress and improving the control of the electrical input.

  3. Dynamic stiffness matrix of partial-interaction composite beams

    Directory of Open Access Journals (Sweden)

    Guangjian Bao

    2015-03-01

    Full Text Available Composite beams have a wide application in building and bridge engineering because of their advantages of mechanical properties, constructability and economic performance. Unlike static characteristics, the methods of studying the dynamic characteristics of partial-interaction composite beams were limited, especially dynamic stiffness matrix method. In this article, the dynamic stiffness matrix of partial-interaction composite beams was derived based on the assumption of the Euler–Bernoulli beam theory, and then it was used to predict the frequencies of the free vibration of the single-span composite beams with various boundary conditions or different axial forces. The corresponding vibration modes and buckling loads were also obtained. From the comparison with the existing results, the numerical results obtained by the proposed method agreed reasonably with those in the literatures. The dynamic stiffness matrix method is an accurate method which can determine natural vibration frequencies and vibration mode shapes in any precision theoretically. As a result, when the higher precision or natural frequencies of higher order are required, the dynamic stiffness matrix method is superior when compared to other approximate and numerical methods. The dynamic stiffness matrix method can also be combined with the finite-element method to calculate the free vibration frequencies and natural mode shapes of composite beams in complex conditions.

  4. Foundation stiffness in the linear modeling of wind turbines

    Science.gov (United States)

    Chiang, Chih-Hung; Yu, Chih-Peng; Chen, Yan-Hao; Lai, Jiunnren; Hsu, Keng-Tsang; Cheng, Chia-Chi

    2017-04-01

    Effects of foundation stiffness on the linear vibrations of wind turbine systems are of concerns for both planning and construction of wind turbine systems. Current study performed numerical modeling for such a problem using linear spectral finite elements. The effects of foundation stiffness were investigated for various combinations of shear wave velocity of soil, size of tower base plate, and pile length. Multiple piles are also included in the models such that the foundation stiffness can be analyzed more realistically. The results indicate that the shear wave velocity of soil and the size of tower base plate have notable effects on the dominant frequency of the turbine-tower system. The larger the lateral dimension, the stiffer the foundation. Large pile cap and multiple spaced piles result in higher stiffness than small pile cap and a mono-pile. The lateral stiffness of a mono-pile mainly depends on the shear wave velocity of soil with the exception for a very short pile that the end constraints may affect the lateral vibration of the superstructure. Effective pile length may be determined by comparing the simulation results of the frictional pile to those of the end-bearing pile.

  5. NAFLD and Increased Aortic Stiffness: Parallel or Common Physiopathological Mechanisms?

    Science.gov (United States)

    Villela-Nogueira, Cristiane A.; Leite, Nathalie C.; Cardoso, Claudia R. L.; Salles, Gil F.

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver diseases worldwide. Liver inflammation and fibrosis related to NAFLD contribute to disease progression and increasing liver-related mortality and morbidity. Increasing data suggest that NAFLD may be linked to atherosclerotic vascular disease independent of other established cardiovascular risk factors. Central arterial stiffness has been recognized as a measure of cumulative cardiovascular risk marker load, and the measure of carotid-femoral pulse wave velocity (cf-PWV) is regarded as the gold standard assessment of aortic stiffness. It has been shown that increased aortic stiffness predicts cardiovascular morbidity and mortality in several clinical settings, including type 2 diabetes mellitus, a well-known condition associated with advanced stages of NAFLD. Furthermore, recently-published studies reported a strong association between NAFLD and increased arterial stiffness, suggesting a possible link in the pathogenesis of atherosclerosis and NAFLD. We sought to review the published data on the associations between NAFLD and aortic stiffness, in order to better understand the interplay between these two conditions and identify possible common physiopathological mechanisms. PMID:27104526

  6. Variable stiffness sandwich panels using electrostatic interlocking core

    Science.gov (United States)

    Heath, Callum J. C.; Bond, Ian P.; Potter, Kevin D.

    2016-04-01

    Structural topology has a large impact on the flexural stiffness of a beam structure. Reversible attachment between discrete substructures allows for control of shear stress transfer between structural elements, thus stiffness modulation. Electrostatic adhesion has shown promise for providing a reversible latching mechanism for controllable internal connectivity. Building on previous research, a thin film copper polyimide laminate has been used to incorporate high voltage electrodes to Fibre Reinforced Polymer (FRP) sandwich structures. The level of electrostatic holding force across the electrode interface is key to the achievable level of stiffness modulation. The use of non-flat interlocking core structures can allow for a significant increase in electrode contact area for a given core geometry, thus a greater electrostatic holding force. Interlocking core geometries based on cosine waves can be Computer Numerical Control (CNC) machined from Rohacell IGF 110 Foam core. These Interlocking Core structures could allow for enhanced variable stiffness functionality compared to basic planar electrodes. This novel concept could open up potential new applications for electrostatically induced variable stiffness structures.

  7. Crosstalk between oxidative and nitrosative stress and arterial stiffness.

    Science.gov (United States)

    Mozos, Ioana; Luca, Constantin Tudor

    2017-02-01

    Arterial stiffness, the expression of reduced arterial elasticity, is an effective predictor of cardiovascular disorders. Oxidative stress is an imbalance between exposure to toxic reactive oxygen species (ROS) and antioxidant systems. The increase in reactive nitrogen species (RNS) is termed nitrosative stress. We review the main mechanisms and products linking arterial stiffness with oxidative and nitrosative stress in several disorders, focusing on recent experimental and clinical data, and the mechanisms explaining benefits of antioxidant therapy. Oxidative and nitrosative stress play important roles in arterial stiffness elevation in several disorders, including diabetes mellitus, hypertension, metabolic syndrome, obesity, peripheral arterial disease, chronic obstructive pulmonary disease, systemic lupus erythematosus, thalassemia, Kawasaki disease and malignant disorders. Oxidative and nitrosative stress are responsible for endothelial dysfunction due to uncoupling of the nitric oxide synthase, oxidative damage to lipids, proteins and DNA in vascular endothelial cells, associated with inflammation, arteriosclerosis and atherosclerosis. Regular physical exercise, caloric restriction, red wine, statins, sartans, metformin, oestradiol, curcumin and combinations of antioxidant vitamins are therapeutic strategies that may decrease arterial stiffness and oxidative stress thus reducing the risk of cardiovascular events. ROS and RNS represent potential therapeutic targets for preventing progression of arterial stiffness.

  8. Mechanical Genomics Identifies Diverse Modulators of Bacterial Cell Stiffness.

    Science.gov (United States)

    Auer, George K; Lee, Timothy K; Rajendram, Manohary; Cesar, Spencer; Miguel, Amanda; Huang, Kerwyn Casey; Weibel, Douglas B

    2016-06-22

    Bacteria must maintain mechanical integrity to withstand the large osmotic pressure differential across the cell membrane and wall. Although maintaining mechanical integrity is critical for proper cellular function, a fact exploited by prominent cell-wall-targeting antibiotics, the proteins that contribute to cellular mechanics remain unidentified. Here, we describe a high-throughput optical method for quantifying cell stiffness and apply this technique to a genome-wide collection of ∼4,000 Escherichia coli mutants. We identify genes with roles in diverse functional processes spanning cell-wall synthesis, energy production, and DNA replication and repair that significantly change cell stiffness when deleted. We observe that proteins with biochemically redundant roles in cell-wall synthesis exhibit different stiffness defects when deleted. Correlating our data with chemical screens reveals that reducing membrane potential generally increases cell stiffness. In total, our work demonstrates that bacterial cell stiffness is a property of both the cell wall and broader cell physiology and lays the groundwork for future systematic studies of mechanoregulation.

  9. Correlates of institutionalized senior veterans' quality of life in Taiwan

    Directory of Open Access Journals (Sweden)

    Hwang Shinn-Jang

    2010-07-01

    Full Text Available Abstract Background Senior veterans living in government sponsored, long-term care (LTC facilities, known as veterans' homes (VHs, are a special minority group in Taiwan. These seniors came from different provinces of mainland China during their teenage years at the end of civil wars in 1945. The situation of institutionalized senior veterans shares many characteristics with the concept of "total institution". Very little quality of life (QOL research has involved senior veterans. This study aimed to explore the QOL and related factors of VH-dwelling senior veterans in Taiwan. Methods Chronic conditions and socio-demographic characteristics of 260 male VH residents were recorded. The Brief Form of the World Health Organization's Quality of Life Questionnaire (WHOQOL-BREF, Taiwanese version; Short-Form 36; Inventory of Socially Supportive Behavior questionnaire; Geriatric Depression Scale-short form; Barthel Index; and instrumental activities of daily living were used. Data analyses including descriptive and inferred statistics were performed using SPSS, version 17. Results WHOQOL-BREF showed acceptable reliability in this study. Compared to Taiwanese male norms, WHOQOL-BREF physical, psychological, and social relationship domain scores were around the 25th percentile, and the environment domain was about the 75th percentile. Our participants scored low in all concepts of SF-36. Although these residents rated the social support of their children, relatives, friends, social and medical staff as low, they gave high satisfaction ratings to their social supports. On multiple stepwise linear regression analysis, depressive symptoms, number of chronic conditions, retired military rank, and relatives' support correlated with QOL in both the physical and psychological domains. Friends' support and depressive symptoms correlated with the social relationships domain. Friends' support and instrumental activities of daily living correlated with the

  10. Output-Based Control of Robots with Variable Stiffness Actuation

    Directory of Open Access Journals (Sweden)

    Gianluca Palli

    2011-01-01

    Full Text Available The output-based control of a redundant robotic manipulator with relevant and adjustable joint stiffness is addressed. The proposed controller is configured as a cascade system that allows the decoupling of the actuators dynamics from the arm dynamics and the consequent reduction of the order of the manipulator dynamic model. Moreover, the proposed controller does not require the knowledge of the whole robot state: only the positions of the actuators and of the joints are necessary. This approach represents a significant simplification with respect to previously proposed state feedback techniques. The problem of controlling simultaneously the position trajectory and the desired stiffness in both the joint and work space is investigated, and the relations between the manipulator redundancy and the selection of both the joint and work space stiffness of the manipulator are discussed. The effectiveness of the proposed approach is verified by simulations of a 3 degrees of freedom planar manipulator.

  11. Associations between bicycling and carotid arterial stiffness in adolescents

    DEFF Research Database (Denmark)

    Ried-Larsen, M; Grøntved, A; Østergaard, Lars;

    2015-01-01

    The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European...... Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys...... modulus [standard beta -0.48 (95% CI -0.91 to -0.06)]. Similar trends were observed when investigating the association between commuter bicycling and carotid arterial stiffness. These associations were not observed in girls. Our observations suggest that increasing bicycling in adolescence may...

  12. Semiactive variable stiffness control for parametric vibration of cables

    Institute of Scientific and Technical Information of China (English)

    Li Hui; Chen Wenli; Ou Jinping

    2006-01-01

    In this paper, a semiactive variable stiffness (SVS) device is used to decrease cable oscillations caused by parametric excitation, and the equation of motion of the parametric vibration of the cable with this SVS device is presented.The ON/OFF control algorithm is used to operate the SVS control device. The vibration response of the cable with the SVS device is numerically studied for a variety of additional stiffness combinations in both the frequency and time domains and for both parametric and classical resonance vibration conditions. The numerical studies further consider the cable sag effect.From the numerical results, it is shown that the SVS device effectively suppresses the cable resonance vibration response, and as the stiffness of the device increases, the device achieves greater suppression of vibration. Moreover, it was shown that the SVS device increases the critical axial displacement of the excitation under cable parametric vibration conditions.

  13. Micromechanical analysis of the behavior of stiff clay

    Institute of Scientific and Technical Information of China (English)

    Zhen-Yu Yin; Ching S. Chang; Pierre-Yves Hicher; Jian-Hua Wang

    2011-01-01

    Cementations formed in geological timescale are observed in various stiff clays.A micromechanical stress strain model is developed for modeling the effect of cementation on the deformation behavior of stiff clay.The proposed approach considers explicitly cementations at intercluster contacts,which is different from conventional model.The concept of inter-cluster bonding is introduced to account for an additional cohesion in shear sliding and a higher yield stress in normal compression.A damage law for inter-cluster bonding is proposed at cluster contacts for the debonding process during mechanical loading.The model is used to simulate numerous stress-path tests on Vallericca stiff clay.The applicability of the present model is evaluated through comparisons between the predicted and the measured results.In order to explain the stress-induced anisotropy arising from extemally applied load,the evolution of local stresses and local strains at inter-cluster planes are discussed.

  14. Enhanced stiffness modeling of manipulators with passive joints

    CERN Document Server

    Pashkevich, Anatoly; Chablat, Damien

    2011-01-01

    The paper presents a methodology to enhance the stiffness analysis of serial and parallel manipulators with passive joints. It directly takes into account the loading influence on the manipulator configuration and, consequently, on its Jacobians and Hessians. The main contributions of this paper are the introduction of a non-linear stiffness model for the manipulators with passive joints, a relevant numerical technique for its linearization and computing of the Cartesian stiffness matrix which allows rank-deficiency. Within the developed technique, the manipulator elements are presented as pseudo-rigid bodies separated by multidimensional virtual springs and perfect passive joints. Simulation examples are presented that deal with parallel manipulators of the Ortholide family and demonstrate the ability of the developed methodology to describe non-linear behavior of the manipulator structure such as a sudden change of the elastic instability properties (buckling).

  15. Mixed, Nonsplit, Extended Stability, Stiff Integration of Reaction Diffusion Equations

    KAUST Repository

    Alzahrani, Hasnaa H.

    2016-07-26

    A tailored integration scheme is developed to treat stiff reaction-diffusion prob- lems. The construction adapts a stiff solver, namely VODE, to treat reaction im- plicitly together with explicit treatment of diffusion. The second-order Runge-Kutta- Chebyshev (RKC) scheme is adjusted to integrate diffusion. Spatial operator is de- scretised by second-order finite differences on a uniform grid. The overall solution is advanced over S fractional stiff integrations, where S corresponds to the number of RKC stages. The behavior of the scheme is analyzed by applying it to three simple problems. The results show that it achieves second-order accuracy, thus, preserving the formal accuracy of the original RKC. The presented development sets the stage for future extensions, particularly, to multidimensional reacting flows with detailed chemistry.

  16. Design and Construction of a Spring Stiffness Testing Machine

    Directory of Open Access Journals (Sweden)

    Olugboji Oluwafemi Ayodeji

    2015-04-01

    Full Text Available A spring stiffness testing machine was produced which differentiates a good spring from bad one using hydraulic principle and locally sourced materials were used to produce at relative low cost and high efficiency. It also categories each spring by stiffness into one of several distinct categories based on its performance under test. This is to ensure that in the final assembly process, springs with similar performance characteristics are mated to ensure a better ride, more précised handling and improved overall vehicle or equipment performance. The construction of the machine involves basically the fabrication process which includes such operation as cutting, benching, welding, grinding, drilling, machining, casting and screw fastening. Taken into consideration under test, were types of compression springs with varying spring loading and their different displacement recorded at different pressures to compare their stiffness.

  17. Estimation of Stiffness Parameter on the Common Carotid Artery

    Science.gov (United States)

    Koya, Yoshiharu; Mizoshiri, Isao; Matsui, Kiyoaki; Nakamura, Takashi

    The arteriosclerosis is on the increase with an aging or change of our living environment. For that reason, diagnosis of the common carotid artery using echocardiogram is doing to take precautions carebropathy. Up to the present, several methods to measure stiffness parameter of the carotid artery have been proposed. However, they have analyzed at the only one point of common carotid artery. In this paper, we propose the method of analysis extended over a wide area of common carotid artery. In order to measure stiffness parameter of common carotid artery from echocardiogram, it is required to detect two border curves which are boundaries between vessel wall and blood. The method is composed of two steps. The first step is the detection of border curves, and the second step is the calculation of stiffness parameter using diameter of common carotid artery. Experimental results show the validity of the proposed method.

  18. Morphological Computation of Haptic Perception of a Controllable Stiffness Probe.

    Directory of Open Access Journals (Sweden)

    Nantachai Sornkarn

    Full Text Available When people are asked to palpate a novel soft object to discern its physical properties such as texture, elasticity, and even non-homogeneity, they not only regulate probing behaviors, but also the co-contraction level of antagonistic muscles to control the mechanical impedance of fingers. It is suspected that such behavior tries to enhance haptic perception by regulating the function of mechanoreceptors at different depths of the fingertips and proprioceptive sensors such as tendon and spindle sensors located in muscles. In this paper, we designed and fabricated a novel two-degree of freedom variable stiffness indentation probe to investigate whether the regulation of internal stiffness, indentation, and probe sweeping velocity (PSV variables affect the accuracy of the depth estimation of stiff inclusions in an artificial silicon phantom using information gain metrics. Our experimental results provide new insights into not only the biological phenomena of haptic perception but also new opportunities to design and control soft robotic probes.

  19. Design of Stiffness for Air Spring Based on ABAQUS

    Directory of Open Access Journals (Sweden)

    Hongguang Li

    2013-01-01

    Full Text Available In this paper, an axisymmetric finite element (FE model of an air spring was carried out with the software ABAQUS to design its target vertical stiffness. The bellows was simulated by the reinforced surface element. The compressed gas in the cavity of the air spring was represented by the hydrostatic fluid element. The target stiffness is obtained by modifying the valid area of the cross section. At last, the results of experiment coincided well with the simulation data. The study shows that the static stiffness of air spring is sensitive to the effective area of the cross section. The conclusion has certain practical significance for the design and the optimization of the same kind of air spring.

  20. Stiffness control of magnetorheological gels for adaptive tunable vibration absorber

    Science.gov (United States)

    Kim, Hyun Kee; Kim, Hye Shin; Kim, Young-Keun

    2017-01-01

    In this study, a stiffness feedback control system for magnetorheological (MR) gel—a smart material of variable stiffness—is proposed, toward the design of a tunable vibration absorber that can adaptively tune to a time varying disturbance in real time. A PID controller was designed to track the required stiffness of the MR gel by controlling the magnitude of the target external magnetic field pervading the MR gel. This paper proposes a novel magnetic field generator that could produce a variable magnetic field with low energy consumption. The performance of the MR gel stiffness control was validated through experiments that showed the MR gel absorber system could be automatically tuned from 56 Hz to 67 Hz under a field of 100 mT to minimize the vibration of the primary system.

  1. Effective Stiffness: Generalizing Effective Resistance Sampling to Finite Element Matrices

    CERN Document Server

    Avron, Haim

    2011-01-01

    We define the notion of effective stiffness and show that it can used to build sparsifiers, algorithms that sparsify linear systems arising from finite-element discretizations of PDEs. In particular, we show that sampling $O(n\\log n)$ elements according to probabilities derived from effective stiffnesses yields an high quality preconditioner that can be used to solve the linear system in a small number of iterations. Effective stiffness generalizes the notion of effective resistance, a key ingredient of recent progress in developing nearly linear symmetric diagonally dominant (SDD) linear solvers. Solving finite elements problems is of considerably more interest than the solution of SDD linear systems, since the finite element method is frequently used to numerically solve PDEs arising in scientific and engineering applications. Unlike SDD systems, which are relatively easy to precondition, there has been limited success in designing fast solvers for finite element systems, and previous algorithms usually tar...

  2. Axial Dynamic Stiffness of Tubular Piles in Viscoelastic Soil

    Directory of Open Access Journals (Sweden)

    Mehdi Bayat

    2016-09-01

    Full Text Available Large offshore wind turbines are founded on jacket structures. In this study, an elastic full-space jacket structure foundation in an elastic and viscoelastic medium is investigated by using boundary integral equations. The jacket structure foundation is modeled as a hollow, long circular cylinder when the dynamic vertical excitation is applied. The smooth surface along the entire interface is considered. The Betti reciprocal theorem along with Somigliana’s identity and Green’s function are employed to drive the dynamic stiffness of jacket structures. Modes of the resonance and anti-resonance are presented in series of Bessel’s function. Important responses, such as dynamic stiffness and phase angle, are compared for different values of the loss factor as the material damping, Young’s modulus and Poisson’s ratio in a viscoelastic soil. Results are verified with known results reported in the literature. It is observed that the dynamic stiffness fluctuates with the loss factor, and the turning point is independent of the loss factor while the turning point increases with load frequency. It is seen that the non-dimensional dynamic stiffness is dependent on Young’s modulus and Poisson’s ratio, whilst the phase angle is independent of the properties of the soil. It is shown that the non-dimensional dynamic stiffness changes linearly with high-frequency load. The conclusion from the results of this study is that the material properties of soil are significant parameters in the dynamic stiffness of jacket structures, and the presented approach can unfold the behavior of soil and give an approachable physical meaning for wave propagation.

  3. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Directory of Open Access Journals (Sweden)

    Usama Elewa

    Full Text Available Arterial stiffness, as measured by pulse wave velocity (PWV, is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5% patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV - (upper limit of the age-adjusted PWV values for the general population. Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  4. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Science.gov (United States)

    Elewa, Usama; Fernandez-Fernandez, Beatriz; Alegre, Raquel; Sanchez-Niño, Maria D; Mahillo-Fernández, Ignacio; Perez-Gomez, Maria Vanessa; El-Fishawy, Hussein; Belal, Dawlat; Ortiz, Alberto

    2015-01-01

    Arterial stiffness, as measured by pulse wave velocity (PWV), is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5%) patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV) was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV) - (upper limit of the age-adjusted PWV values for the general population). Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  5. [Stiff baby syndrome is a rare cause of neonatal hypertonicity].

    Science.gov (United States)

    Rønne, Maria Sode; Nielsen, Preben Berg; Mogensen, Christian Backer

    2014-02-24

    Stiff baby syndrome (hyperekplexia) is a rare genetic disorder. The condition can easily be misdiagnosed as epilepsy or severe sepsis because of hypertonicity and seizure-like episodes and has an increased risk of severe apnoea and sudden infant death. Tapping of the nasal bridge inducing a startle response is the clinical hallmark. We report cases of two sisters born with stiff baby syndrome with hypertonicity, exaggerated startle reaction and cyanosis. The syndrome has a good prognosis if treated with clonazepam and both cases were developmental normal after one year.

  6. Diagnosis and clinical assessment of a stiff shoulder.

    Science.gov (United States)

    Armstrong, Alison

    2015-04-01

    The assessment of a stiff shoulder is explored, the necessary investigations to reach a diagnosis are discussed, and the likely causes that can contribute to a frozen shoulder are described. Two flow diagrams are included to help in reaching a conclusion when seeing a patient with a stiff shoulder. The key elements to reaching that conclusion are: carefully listening to the patients story, noting whether there has been a history of trauma, as well as a careful and thorough examination and a plain X-ray with two views.

  7. Fast Stiffness Matrix Calculation for Nonlinear Finite Element Method

    Directory of Open Access Journals (Sweden)

    Emir Gülümser

    2014-01-01

    Full Text Available We propose a fast stiffness matrix calculation technique for nonlinear finite element method (FEM. Nonlinear stiffness matrices are constructed using Green-Lagrange strains, which are derived from infinitesimal strains by adding the nonlinear terms discarded from small deformations. We implemented a linear and a nonlinear finite element method with the same material properties to examine the differences between them. We verified our nonlinear formulation with different applications and achieved considerable speedups in solving the system of equations using our nonlinear FEM compared to a state-of-the-art nonlinear FEM.

  8. Beam section stiffness properties usig 3D finite elements

    DEFF Research Database (Denmark)

    Couturier, Philippe; Krenk, Steen; Høgsberg, Jan Becker

    2013-01-01

    The cross-section properties of a beam is characterized by a six by six stiffness matrix, relating the six generalized strains to the conjugate section forces. The problem is formulated as a single-layer finite element model of a slice of the beam, on which the six deformation modes are imposed via...... Lagrange multipliers. The Lagrange multipliers represent the constraining forces, and thus combine to form the cross-section stiffness matrix. The theory is illustrated by a simple isotropic cross-section....

  9. Simplified formula for isoparametric quadrilateral element stiffness matrix

    Energy Technology Data Exchange (ETDEWEB)

    Changlian, X.

    1987-02-01

    Homogeneous parallelogram and quasi-parallelogram elements are usually used in finite element seismic modeling. Theoretically, the coordinates of element nodes may be arbitrary values on condition that elements are successive and not superposed. Isoparametric quadrilateral elements, whose nodes are presumed to be in laterally uniform distribution, are used so that not only unit stiffness matrix formula is essentially simplified to cut computing time but also finite element method remains flexible enough to be used in complex modeling. Simplified formulae for computing the stiffness matrices in four cases are derived, which, compared with corresponding Gauss integration algorithm, can cut 94-98% computing time.

  10. Effects of Stiffness on Short, Semiflexible Homopolymer Chains

    Science.gov (United States)

    Seaton, Daniel T.; Schnabel, Stefan; Bachmann, Michael; Landau, David P.

    2012-08-01

    Conformational and transition behavior of finite, semiflexible homopolymers is studied using an extension of the Wang-Landau algorithm. Generation of a flat distribution in the sampling parameters energy and stiffness allows for efficient investigation of transitions between various conformational phases. Of particular importance is the ability to predict behavior for a given stiffness value, where three classes of minimum energy conformations are expected: Solid-globular, rod-like and toroidal. We present first results highlighting the behavior of a single N = 20 length chain.

  11. Weight reduction and aortic stiffness in obese children and adolescents

    DEFF Research Database (Denmark)

    Hvidt, K. N.; Olsen, M. H.; Ibsen, H.

    2015-01-01

    Little is known about the effect of weight reduction on aortic stiffness and especially so in the young. The present study investigates whether weight reduction influences aortic stiffness in obese children and adolescents. Carotid-femoral pulse wave velocity (cfPWV) and augmentation index at heart...... rate 75 (AIx@HR75) were measured in 72 obese patients aged 10-18 years at baseline and after 1-year of lifestyle intervention (follow-up). We found that although the degree of obesity decreased (Delta body mass index z-score: -0.24 +/- 0.45, P ....27 +/- 0.47 ms(-1), P obesity measures. No significant change...

  12. An asymptotic approach to the adhesion of thin stiff films

    CERN Document Server

    Dumont, Serge; Rizzoni, Raffaella

    2013-01-01

    In this paper, the asymptotic first order analysis, both mathematical and numerical, of two structures bonded together is presented. Two cases are considered, the gluing of an elastic structure with a rigid body and the gluing of two elastic structures. The glue is supposed to be elastic and to have its stiffness of the same order than those of the elastic structures. An original numerical method is developed to solve the mechanical problem of stiff interface at order 1, based on the Nitsche's method. Several numerical examples are provided to show the efficiency of both the analytical approximation and the numerical method.

  13. Experimental measurement of the stiffness of the cupula.

    Science.gov (United States)

    Grant, J W; Van Buskirk, W C

    1976-06-01

    An experimental procedure is described which consists of cutting the canal duct, inserting a micropipette and administering known volumetric displacements to the cupula. The cupula is made visible by dying the endolymph. Known displacements are administered to the cupula, and the time constant of the return to its equilibrium position is measured. With this information, the stiffness of the cupula is calculated. The experiment was successfully carried out on five White King pigeons. The mean stiffness found in somewhat less than other results reported in the literature, and reasons for this discrepancy are noted.

  14. Generalized seniority states and isomers in tin isotopes

    Science.gov (United States)

    Jain, Ashok Kumar; Maheshwari, Bhoomika

    2017-07-01

    Isomeric studies in neutron-rich nuclei are a powerful tool for exploring structure at the nuclear extremes. In this paper we discuss the systematic features of the excitation energies and transition probabilities of Sn isotopes in the region N = 50-82 and present their basic understanding in terms of generalized seniority. We further use generalized seniority as a probe to explore the neutron-rich {6}+ seniority isomers in 134-138Sn, and to validate the neutron single-particle energies beyond N = 82. We show that these isomers behave as generalized seniority isomers, where the so-called anomalous {{B}}(E2) behavior of the {6}+ isomer in 136Sn may be naturally explained. We support these results by shell model calculations, where the latest neutron single-particle energies of the N = 82-126 region have been used, and the i13/2 neutron single-particle energy has been suitably modified in the renormalized charge-dependent Bonn interaction. This entails a possible new subshell closure at N = 112 due to the suggested higher location of the i13/2 neutron orbital, also consistent with the choice of orbitals in the generalized seniority scheme. However, a small reduction in the f7/2 two-body matrix elements is still required in the shell model calculations to consistently reproduce the experimental level energies as well as the transition probabilities in 134-138Sn isotopes.

  15. Stiffness, Workspace Analysis and Optimization for 3UPU Parallel Robot Mechanism

    Directory of Open Access Journals (Sweden)

    Cui Guohua

    2013-09-01

    Full Text Available In this paper, an approach based on the particle swarm optimization is used to optimize the workspace and global stiffness of the 3UPU mechanism simultaneously due to the fact that the workspace is affected while optimizing the stiffness of the mechanism and vice versa. When optimizing one particular performance, one needs to have an objective function. Here the workspace volume of the mechanism is used as an objective function to evaluate the workspace performance of the mechanism. The leading diagonal elements of the stiffness matrix represent pure stiffness in each direction, but this stiffness changes when the moving platform position changes. We call this stiffness as local stiffness. When using the local stiffness as an objective function for stiffness optimization, it can only represent the stiffness in one particular position. Here the global stiffness of the mechanism is used as an objective function to optimize the stiffness of the mechanism. The global stiffness represents mean stiffness over the workspace.  

  16. Hybrid-Aware Model for Senior Wellness Service in Smart Home.

    Science.gov (United States)

    Jung, Yuchae

    2017-05-22

    Smart home technology with situation-awareness is important for seniors to improve safety and security. With the development of context-aware computing, wearable sensor technology, and ubiquitous computing, it is easier for seniors to manage their health problem in smart home environment. For monitoring senior activity in smart home, wearable, and motion sensors-such as respiration rate (RR), electrocardiography (ECG), body temperature, and blood pressure (BP)-were used for monitoring movements of seniors. For context-awareness, environmental sensors-such as gas, fire, smoke, dust, temperature, and light sensors-were used for senior location data collection. Based on senior activity, senior health status can be classified into positive and negative. Based on senior location and time, senior safety is classified into safe and emergency. In this paper, we propose a hybrid inspection service middleware for monitoring elderly health risk based on senior activity and location. This hybrid-aware model for the detection of abnormal status of seniors has four steps as follows: (1) data collection from biosensors and environmental sensors; (2) monitoring senior location and time of stay in each location using environmental sensors; (3) monitoring senior activity using biometric data; finally, (4) expectation-maximization based decision-making step recommending proper treatment based on a senior health risk ratio.

  17. Stiffness characterization of a 3-PPR planar parallel manipulator with actuation compliance

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl

    2015-01-01

    This paper investigates the stiffness of a compliant planar parallel manipulator. Instead of establishing stiffness matrix directly for planar mechanisms, we adopt the modeling approach for spatial mechanisms, which allows us to derive two decoupled homogeneous matrices, corresponding to the tran......This paper investigates the stiffness of a compliant planar parallel manipulator. Instead of establishing stiffness matrix directly for planar mechanisms, we adopt the modeling approach for spatial mechanisms, which allows us to derive two decoupled homogeneous matrices, corresponding...... submatrices. In addition, the influence of the nonlinear actuation compliance to the manipulator stiffness is investigated, and the established stiffness model is experimentally verified....

  18. Stiffness characterization of a 3-PPR planar parallel manipulator with actuation compliance

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl

    2015-01-01

    This paper investigates the stiffness of a compliant planar parallel manipulator. Instead of establishing stiffness matrix directly for planar mechanisms, we adopt the modeling approach for spatial mechanisms, which allows us to derive two decoupled homogeneous matrices, corresponding...... to the translational and rotational stiffness. This is achieved by resorting to the generalized eigenvalue problem, through which the eigenscrew decomposition is implemented to yield six screw springs. The principal stiffnesses and their directions are then identified from the eigenvalue problem of the two separated...... submatrices. In addition, the influence of the nonlinear actuation compliance to the manipulator stiffness is investigated, and the established stiffness model is experimentally verified....

  19. Physiological profile of senior and junior England international amateur boxers.

    Science.gov (United States)

    Smith, Marcus S

    2006-01-01

    Despite worldwide popularity of amateur boxing, research focussed on the physiological demands of the sport is limited. The physiological profile of Senior and Junior England international amateur boxers is presented. A gradual (8 to 21-days) and rapid (0 to 7-days) phase of body weight reduction was evident with 2.2 ± 0.3 % of the 7.0 ± 0. 8 % weight loss occurring over the final 24-hours. An increase in body weight >4% was observed following a recovery period. High urine osmolality values (> 1000 mOsm·kg(-1)) were recorded during training and competition. High post-competition blood lactate values (>13.5 mmol·l(-1)) highlighted the need for a well-developed anaerobic capacity and the importance of not entering the ring in a glycogen depleted state. The aerobic challenge of competition was demonstrated by maximum heart rate values being recorded during 'Open' sparring. Mean body fat values of 9-10% were similar to those reported for other weight classified athletes. Normal resting values were reported for hematocrit (Senior 48 ± 2 % and Junior 45 ± 2 %), haemoglobin (Senior 14.7 ± 1.0 g·dl(-1) and Junior 14.5 ± 0.8 g·dl(-1)), bilirubin (Senior 15.3 ± 6.2 µmol·l-1(-1)) and ferritin (Senior 63.3 ± 45.7 ng·ml(-1)). No symptoms associated with asthma or exercise-induced asthma was evident. A well- developed aerobic capacity was reflected in the Senior VO2max value of 63.8 ± 4.8 ml·kg(-1)·min(-1). Senior lead hand straight punching force (head 1722 ± 700 N and body 1682 ± 636 N) was lower than the straight rear hand (head 2643 ± 1273 N and body 2646 ± 1083 N), lead hook (head 2412 ± 813 N and body 2414 ± 718 N) and rear hook (head 2588 ± 1040 N and body 2555 ± 926 N). It was concluded that amateur boxing performance is dependent on the interplay between anaerobic and aerobic energy systems. Current weight making methods may lead to impaired substrate availability, leading to reduced competitive performance and an increased risk to a boxers

  20. Generalized seniority with realistic interactions in open-shell nuclei

    CERN Document Server

    Caprio, M A; Cai, K; Constantinou, Ch; Hellemans, V

    2014-01-01

    Generalized seniority provides a truncation scheme for the nuclear shell model, based on pairing correlations, which offers the possibility of dramatically reducing the dimensionality of the nuclear shell-model problem. Systematic comparisons against results obtained in the full shell-model space are required to assess the viability of this scheme. Here, we extend recent generalized seniority calculations for semimagic nuclei, the Ca isotopes, to open-shell nuclei, with both valence protons and valence neutrons. The even-mass Ti and Cr isotopes are treated in a full major shell and with realistic interactions, in the generalized seniority scheme with one broken proton pair and one broken neutron pair. Results for level energies, orbital occupations, and electromagnetic observables are compared with those obtained in the full shell-model space. We demonstrate that, even for the Ti isotopes, significant benefit would be obtained in going beyond the approximation of one broken pair of each type, while the Cr iso...

  1. SENIOR EMPLOYEES ON THE JOB MARKET OF EUROPEAN UNION

    Directory of Open Access Journals (Sweden)

    Laszlo GULYÁS

    2009-01-01

    Full Text Available In the European countries life expectancy is growing, but people tend to retireearlier and earlier. The aim of our paper is to examine what measures theindividual European countries take in order to keep senior citizens on theirrespective job markets as long as possible. Our essay consists of three parts.In the first part we examine the reform of the pension system. In the secondpart we survey the changing in-company employment policies. In the thirdpart we examine the attempt of improvement of the employability of seniorcitizens themselves. The final conclusion of our paper can be summarised asfollows: senior employees in general represent a significant group in humanresources, the potentials of which ought to be and need to be utilized.Employers need to understand that the employment of senior people has itsadvantages. It is also very important to act accordingly.

  2. Simultaneously high stiffness and damping in nanoengineered microtruss composites.

    Science.gov (United States)

    Meaud, Julien; Sain, Trisha; Yeom, Bongjun; Park, Sei Jin; Shoultz, Anna Brieland; Hulbert, Gregory; Ma, Zheng-Dong; Kotov, Nicholas A; Hart, A John; Arruda, Ellen M; Waas, Anthony M

    2014-04-22

    Materials combining high stiffness and mechanical energy dissipation are needed in automotive, aviation, construction, and other technologies where structural elements are exposed to dynamic loads. In this paper we demonstrate that a judicious combination of carbon nanotube engineered trusses held in a dissipative polymer can lead to a composite material that simultaneously exhibits both high stiffness and damping. Indeed, the combination of stiffness and damping that is reported is quite high in any single monolithic material. Carbon nanotube (CNT) microstructures grown in a novel 3D truss topology form the backbone of these nanocomposites. The CNT trusses are coated by ceramics and by a nanostructured polymer film assembled using the layer-by-layer technique. The crevices of the trusses are then filled with soft polyurethane. Each constituent of the composite is accurately modeled, and these models are used to guide the manufacturing process, in particular the choice of the backbone topology and the optimization of the mechanical properties of the constituent materials. The resulting composite exhibits much higher stiffness (80 times) and similar damping (specific damping capacity of 0.8) compared to the polymer. Our work is a step forward in implementing the concept of materials by design across multiple length scales.

  3. Analytical stiffness matrices with Green-Lagrange strain measure

    DEFF Research Database (Denmark)

    Pedersen, Pauli

    2005-01-01

    Separating the dependence on material and stress/strain state from the dependence on initial geometry, we obtain analytical secant and tangent stiffness matrices. For the case of a linear displacement triangle with uniform thickness and uniform constitutive behaviour closed-form results are listed...

  4. Stiffness and design for strength of trapezoidal Belleville springs

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Pedersen, Pauli

    2011-01-01

    in this paper. Finite element results are compared with analytical predictions and critically analysed in terms of the effect of Poisson ratio, overall stiffness, and stress distribution in the spring. This is done in order to verify the range of validity of design standards. Finite element analysis emerges...

  5. Reproducibility of the ambulatory arterial stiffness index in hypertensive patients

    DEFF Research Database (Denmark)

    Dechering, D.G.; Steen, M.S. van der; Adiyaman, A.;

    2008-01-01

    BACKGROUND: We studied the repeatability of the ambulatory arterial stiffness index (AASI), which can be computed from 24-h blood pressure (BP) recordings as unity minus the regression slope of diastolic on systolic BP. METHODS: One hundred and fifty-two hypertensive outpatients recruited...

  6. Pre-diabetes and arterial stiffness in uraemic patients

    DEFF Research Database (Denmark)

    Hornum, Mads; Clausen, Peter; Kjaergaard, Jesper;

    2010-01-01

    In order to address factors of relevance for new onset diabetes mellitus and cardiovascular disease after kidney transplantation, we investigated the presence of pre-diabetes, arterial stiffness and endothelial dysfunction in patients with end-stage renal disease (ESRD) accepted for kidney...

  7. Stiffness and shrinkage of green and dry joists

    Science.gov (United States)

    Lyman W. Wood; Lawrence A. Soltis

    1964-01-01

    This report gives information on the edgewise modulus of elasticity, stiffness, and shrinkage of 360 joists in three species, three grades, and two sizes, each species obtained from two sources. Each joist was evaluated nondestructively at four moisture content values ranging from the green condition to about 11 percent. Information is also given on specific gravity,...

  8. Sport stretching : Effect on passive muscle stiffness of short hamstrings

    NARCIS (Netherlands)

    Halbertsma, JPK; vanBolhuis, AI; Goeken, LNH

    1996-01-01

    Objective: To evaluate the effects of one 10-minute stretch on muscle stiffness in subjects with short hamstrings. Design: Randomized control trial. Setting: Laboratory for human movement sciences in the department of rehabilitation of a university hospital. Subjects: Sixteen students from the Depar

  9. Variable stiffness actuators: review on design and components

    NARCIS (Netherlands)

    Wolf, Sebastian; Grioli, Giorgio; Eiberger, Oliver; Friedl, Werner; Grebenstein, Markus; Höppner, Hannes; Burdet, Etienne; Caldwell, Darwin G.; Carloni, Raffaella; Catalano, Manuel G.; Lefeber, Dirk; Stramigioli, Stefano; Tsagarakis, Nikos; Damme, van Michaël; Ham, van Ronald; Vanderborght, Bram; Visser, Ludo C.; Bicchi, Antonio; Albu-Schäffer, Alin

    2016-01-01

    Variable stiffness actuators (VSAs) are complex mechatronic devices that are developed to build pas- sively compliant, robust, and dexterous robots. Numerous different hardware designs have been developed in the past two decades to address various demands on their functionality. This review paper gi

  10. Extracellular matrix stiffness dictates Wnt expression through integrin pathway.

    Science.gov (United States)

    Du, Jing; Zu, Yan; Li, Jing; Du, Shuyuan; Xu, Yipu; Zhang, Lang; Jiang, Li; Wang, Zhao; Chien, Shu; Yang, Chun

    2016-02-08

    It is well established that extracellular matrix (ECM) stiffness plays a significant role in regulating the phenotypes and behaviors of many cell types. However, the mechanism underlying the sensing of mechanical cues and subsequent elasticity-triggered pathways remains largely unknown. We observed that stiff ECM significantly enhanced the expression level of several members of the Wnt/β-catenin pathway in both bone marrow mesenchymal stem cells and primary chondrocytes. The activation of β-catenin by stiff ECM is not dependent on Wnt signals but is elevated by the activation of integrin/ focal adhesion kinase (FAK) pathway. The accumulated β-catenin then bound to the wnt1 promoter region to up-regulate the gene transcription, thus constituting a positive feedback of the Wnt/β-catenin pathway. With the amplifying effect of positive feedback, this integrin-activated β-catenin/Wnt pathway plays significant roles in mediating the enhancement of Wnt signal on stiff ECM and contributes to the regulation of mesenchymal stem cell differentiation and primary chondrocyte phenotype maintenance. The present integrin-regulated Wnt1 expression and signaling contributes to the understanding of the molecular mechanisms underlying the regulation of cell behaviors by ECM elasticity.

  11. Stiffness of the healing medial collateral ligament of the mouse.

    NARCIS (Netherlands)

    Gijssen, Y.; Sierevelt, I.N.; Kooloos, J.G.M.; Blankevoort, L.

    2004-01-01

    The knee joints of mice can serve as a model for studying knee ligament properties. The goal of our study was to measure the structural stiffness of the medial collateral ligament (MCL) of the murine knee. A tensile test was developed for this purpose. First 84 femur-MCL-tibia complexes of

  12. Torsion stiffness of a protein pair determined by magnetic particles

    NARCIS (Netherlands)

    Janssen, X.J.A.; Van Noorloos, J.M.; Jacob, A.; Van IJzendoorn, L.J.; De Jong, A.M.; Prins, M.W.J.

    2012-01-01

    We demonstrate the ability to measure torsion stiffness of a proteincomplex by applying a controlled torque on a magnetic particle. Asa model system we use protein G bound to an IgG antibody. The protein pair is held between a magnetic particle and a polystyrene substrate. The angular orientation of

  13. Wide Stiffness Range Cavity Optomechanical Sensors for Atomic Force Microscopy

    CERN Document Server

    Liu, Yuxiang; Aksyuk, Vladimir; Srinivasan, Kartik

    2012-01-01

    We report on progress in developing compact sensors for atomic force microscopy (AFM), in which the mechanical transducer is integrated with near-field optical readout on a single chip. The motion of a nanoscale, doubly-clamped cantilever was transduced by an adjacent high quality factor silicon microdisk cavity. In particular, we show that displacement sensitivity on the order of 1 fm/(Hz)^(1/2) can be achieved while the cantilever stiffness is varied over four orders of magnitude (\\approx 0.01 N/m to \\approx 290 N/m). The ability to transduce both very soft and very stiff cantilevers extends the domain of applicability of this technique, potentially ranging from interrogation of microbiological samples (soft cantilevers) to imaging with high resolution (stiff cantilevers). Along with mechanical frequencies (> 250 kHz) that are much higher than those used in conventional AFM probes of similar stiffness, these results suggest that our cavity optomechanical sensors may have application in a wide variety of hig...

  14. A Multiscale Mechanical Model for Plant Tissue Stiffness

    Directory of Open Access Journals (Sweden)

    Damiano Pasini

    2013-06-01

    Full Text Available Plant petioles and stems are hierarchical cellular structures, displaying structuralfeatures defined at multiple length scales. The current work focuses on the multi-scalemodelling of plant tissue, considering two orders of structural hierarchy, cell wall and tissue.The stiffness of plant tissue is largely governed by the geometry of the tissue cells, thecomposition of the cell wall and the structural properties of its constituents. The cell wallis analogous to a fiber reinforced composite, where the cellulose microfibril (CMF is theload bearing component. For multilayered cell wall, the microfibril angle (MFA in themiddle layer of the secondary cell wall (S2 layer largely affects the longitudinal stiffnessfor values up to 40o. The MFA in turn influences the overall wall stiffness. In this work,the effective stiffness of a model system based on collenchyma cell wall of a dicotyledonousplant, the Rheum rhabarbarum, is computed considering generic MFA and volume fractions.At the cellular level, a 2-D Finite Edge Centroidal Voronoi tessellation (FECVT has beendeveloped and implemented to generate the non-periodic microstructure of the plant tissue.The effective elastic properties of the cellular tissue are obtained through finite elementanalysis (FEA of the Voronoi model coupled with the cell wall properties. The stiffness ofthe hierarchically modeled tissue is critically important in determining the overall structuralproperties of plant petioles and stems.

  15. Axially Symmetric Cosmological Mesonic Stiff Fluid Models in Lyra's Geometry

    CERN Document Server

    Gad, Ragab M

    2009-01-01

    In this paper, we obtained a new class of axially symmetric cosmological mesonic stiff fluid models in the context of Lyra's geometry. Expressions for the energy, pressure and the massless scalar field are derived by considering the time dependent displacement field. We found that the mesonic scalar field depends on only $t$ coordinate. Some physical properties of the obtained models are discussed.

  16. On Stiffness Regulators with Dissipative Injection for Robot Manipulators

    Directory of Open Access Journals (Sweden)

    César Chávez-Olivares

    2015-06-01

    Full Text Available The stiffness controller proposed by Salisbury is an interaction control strategy designed to achieve a desired form of static behavior as regards the interaction of a robot manipulator with the environment. The main idea behind this approach is the simulation of a multidimensional linear spring - or linear elastic material - using the difference between the actual position of the end-effector and a constant position (relaxed point, multiplied by a constant stiffness matrix. In this paper, this idea is generalized with the objective of proposing a controller structure that includes a family of stiffness models based on the idea of linear elastic materials. The new controller structure also includes a damping term in order to have control over energy dissipation, as well as a term added for the purpose of compensating the gravity forces of the links. The stability analysis of the proposed controller was performed in the Lyapunov sense. The new stiffness controller is presented as a case study and compared to other cases, such as the Salisbury controller (Cartesian PD and the tanh-tanh controller. Experimental results using a three degrees-of-freedom direct-drive robot for the evaluation of controllers in a constrained motion task are presented.

  17. Variable stiffness and damping suspension system for train

    Science.gov (United States)

    Sun, Shuaishuai; Deng, Huaxia; Li, Weihua

    2014-03-01

    As the vibration of high speed train becomes fierce when the train runs at high speed, it is crucial to develop a novel suspension system to negotiate train's vibration. This paper presents a novel suspension based on Magnetorheological fluid (MRF) damper and MRF based smart air spring. The MRF damper is used to generate variable damping while the smart air spring is used to generate field-dependent stiffness. In this paper, the two kind smart devices, MRF dampers and smart air spring, are developed firstly. Then the dynamic performances of these two devices are tested by MTS. Based on the testing results, the two devices are equipped to a high speed train which is built in ADAMS. The skyhook control algorithm is employed to control the novel suspension. In order to compare the vibration suppression capability of the novel suspension with other kind suspensions, three other different suspension systems are also considered and simulated in this paper. The other three kind suspensions are variable damping with fixed stiffness suspension, variable stiffness with fixed damping suspension and passive suspension. The simulation results indicate that the variable damping and stiffness suspension suppresses the vibration of high speed train better than the other three suspension systems.

  18. Development of a variable stiffness and damping tunable vibration isolator

    CSIR Research Space (South Africa)

    Cronje, JM

    2005-03-01

    Full Text Available In this paper we report on the development of a variable stiffness and damping Liquid Inertia Vibration Eliminator (LIVE) vibration isolator. The result is the ability to shift the isolation frequency of the isolator and also to change...

  19. Riparian Sediment Delivery Ratio: Stiff Diagrams and Artifical Neural Networks

    Science.gov (United States)

    Various methods are used to estimate sediment transport through riparian buffers and grass jilters with the sediment delivery ratio having been the most widely applied. The U.S. Forest Service developed a sediment delivery ratio using the stiff diagram and a logistic curve to int...

  20. Stiffness mapping of lower leg muscles during passive dorsiflexion.

    Science.gov (United States)

    Le Sant, Guillaume; Nordez, Antoine; Andrade, Ricardo; Hug, François; Freitas, Sandro; Gross, Raphaël

    2017-05-01

    It is challenging to differentiate the mechanical properties of synergist muscles in vivo. Shear wave elastography can be used to quantify the shear modulus (i.e. an index of stiffness) of a specific muscle. This study assessed the passive behavior of lower leg muscles during passive dorsiflexion performed with the knee fully extended (experiment 1, n = 22) or with the knee flexed at 90° (experiment 2, n = 20). The shear modulus measurements were repeated twice during experiment 1 to assess the inter-day reliability. During both experiments, the shear modulus of the following plantar flexors was randomly measured: gastrocnemii medialis (GM) and lateralis (GL), soleus (SOL), peroneus longus (PL), and the deep muscles flexor digitorum longus (FDL), flexor hallucis longus (FHL), tibialis posterior (TP). Two antagonist muscles tibialis anterior (TA), and extensor digitorum longus (EDL) were also recorded. Measurements were performed in different proximo-distal regions for GM, GL and SOL. Inter-day reliability was adequate for all muscles (coefficient of variation muscles and PL exhibited low levels of stiffness during the stretch in young asymptomatic adults, which was unknown until now. These results provide a deeper understanding of passive mechanical properties and the distribution of stiffness between and within the plantar flexor muscles during stretching between them and thus could be relevant to study the effects of aging, disease progression, and rehabilitation on stiffness. © 2017 Anatomical Society.

  1. Arterial stiffness as a risk factor for coronary artery disease.

    Science.gov (United States)

    Liao, Josh; Farmer, John

    2014-02-01

    Hypertension is a major modifiable risk factor, and clinical trials have demonstrated that successful reduction of elevated blood pressure to target levels translates into decreased risk for the development of coronary artery disease, stroke, heart failure, and renal failure. The arterial system had previously been regarded as a passive conduit for the transportation of arterial blood to peripheral tissues. The physiologic role the arterial system was greatly expanded by the recognition of the central role of the endothelial function in a variety of physiologic processes. The role of arterial function and structure in cardiovascular physiology was expanded with the development of a variety of parameters that evaluate arterial stiffness. Markers of arterial stiffness have been correlated with cardiovascular outcomes, and have been classified as an emerging risk factor that provides prognostic information beyond standard stratification strategies involving hypertension, diabetes, obesity, dyslipidemia and smoking. Multiple epidemiologic studies have correlated markers of arterial stiffness such as pulse-wave velocity, augmentation index and pulse pressure with risk for the development of fatal and nonfatal cardiovascular events. Additionally, measurements of arterial stiffness had clarified the results of clinical trials that demonstrated differing impacts on clinical outcomes, despite similar reductions in blood pressure, as measured by brachial and sphygmomanometry.

  2. Stiffness and hysteresis properties of some prosthetic feet

    NARCIS (Netherlands)

    van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hyster

  3. Stiffness of cancer cells measured with an AFM indentation method.

    Science.gov (United States)

    Hayashi, Kozaburo; Iwata, Mayumi

    2015-09-01

    The stiffness of cancer cells and its changes during metastasis are very important for understanding the pathophysiology of cancer cells and the mechanisms of metastasis of cancer. As the first step of the studies on the mechanics of cancer cells during metastasis, we determined the elasticity and stiffness of cancer cells with an indentation method using an atomic force microscope (AFM), and compared with those of normal cells. In most of the past AFM studies, Young׳s elastic moduli of cells have been calculated from force-indentation data using Hertzian model. As this model is based on several important assumptions including infinitesimal strain and Hooke׳s linear stress-strain law, in the exact sense it cannot be applied to cells that deform very largely and nonlinearly. To overcome this problem, we previously proposed an equation F=a[exp(bδ)-1] to describe relations between force (F) and indentation (δ), where a and b are parameters relating with cellular stiffness. In the present study, we applied this method to cancer cells instead of Young׳s elastic modulus. The conclusions obtained are: 1) AFM indentation test data of cancer cells can be very well described by the above equation, 2) cancer cells are softer than normal cells, and 3) there are no significant locational differences in the stiffness of cancer cells between the central and the peripheral regions. These methods and results are useful for studying the mechanics of cancer cells and the mechanisms of metastasis.

  4. Step-parallel algorithms for stiff initial value problems

    NARCIS (Netherlands)

    Veen, W.A. van der

    1995-01-01

    For the parallel integration of stiff initial value problems, three types of parallelism can be employed: 'parallelism across the problem', 'parallelism across the method' and 'parallelism across the steps'. Recently, methods based on Runge-Kutta schemes that use parallelism across the method have b

  5. [Progress on cervical muscle strength and soft tissue stiffness testing].

    Science.gov (United States)

    Ma, Ming; Zhang, Shi-min

    2015-08-01

    Biomechanical evaluation of neck muscles has important significance in the diagnosis and treatment for cervical spondylosis, the neck muscle strength and soft tissue stiffness test is two aspects of biomechanical testing. Isometric muscle testing operation is relatively simple, the cost is lower, which can evaluate the muscle force below grade 3. However, isokinetic muscle strength testing can assess the muscle strength of joint motion in any position. It is hard to distinguish stiffness difference in different soft tissues when the load-displacement curve is used to evaluate the local soft tissue stiffness. Elasticity imaging technique can not only show the elastic differences of different tissues by images, but also quantify the elastic modulus of subcutaneous tissues and muscles respectively. Nevertheless, it is difficult to observe the flexibility of the cervical spine by means of the analysis of the whole neck stiffness. In a word, a variety of test method will conduce not only the biomechanical evaluation of neck muscles, but also making an effective biomechanics mathematical model of neck muscles. Besides, isokinetic muscle testing and the elasticity imaging technology still need further validation and optimization before they are better applied to neck muscles biomechanical testing.

  6. On implicit Taylor series methods for stiff ODEs

    Energy Technology Data Exchange (ETDEWEB)

    Kirlinger, G. [Technische Univ., Vienna (Austria). Inst. fuer Angewandte und Numerische Mathematik; Corliss, G.F. [Argonne National Lab., IL (United States)

    1991-12-31

    Several versions of implicit Taylor series methods (ITSM) are presented and evaluated. Criteria for the approximate solution of ODEs via ITSM are given. Some ideas, motivations, and remarks on the inclusion of the solution of stiff ODEs are outlined. 25 refs., 3 figs.

  7. On implicit Taylor series methods for stiff ODEs

    Energy Technology Data Exchange (ETDEWEB)

    Kirlinger, G. (Technische Univ., Vienna (Austria). Inst. fuer Angewandte und Numerische Mathematik); Corliss, G.F. (Argonne National Lab., IL (United States))

    1991-01-01

    Several versions of implicit Taylor series methods (ITSM) are presented and evaluated. Criteria for the approximate solution of ODEs via ITSM are given. Some ideas, motivations, and remarks on the inclusion of the solution of stiff ODEs are outlined. 25 refs., 3 figs.

  8. Cardiovascular Health and Arterial Stiffness: The Maine Syracuse Longitudinal Study

    Science.gov (United States)

    Crichton, Georgina E; Elias, Merrill F; Robbins, Michael A

    2014-01-01

    Ideal cardiovascular health is a recently defined construct by the American Heart Association (AHA) to promote cardiovascular disease reduction. Arterial stiffness is a major risk factor for cardiovascular disease. The extent to which the presence of multiple prevalent cardiovascular risk factors and health behaviors is associated with arterial stiffness is unknown. The aim of this study was to examine the association between the AHA construct of cardiovascular health and arterial stiffness, as indexed by pulse wave velocity and pulse pressure. The AHA health metrics, comprising of four health behaviors (smoking, body mass index, physical activity, and diet) and three health factors (total cholesterol, blood pressure, and fasting plasma glucose) were evaluated among 505 participants in the Maine-Syracuse Longitudinal Study. Outcome measures were carotid-femoral pulse wave velocity (PWV) and pulse pressure measured at 4 to 5-year follow-up. Better cardiovascular health, comprising both health factors and behaviors, was associated with lower arterial stiffness, as indexed by pulse wave velocity and pulse pressure. Those with at least five health metrics at ideal levels had significantly lower PWV (9.8 m/s) than those with two or less ideal health metrics (11.7 m/s) (P<0.001). This finding remained with the addition of demographic and PWV-related variables (P=0.004). PMID:24384629

  9. Design optimization of a twist compliant mechanism with nonlinear stiffness

    Science.gov (United States)

    Tummala, Y.; Frecker, M. I.; Wissa, A. A.; Hubbard, J. E., Jr.

    2014-10-01

    A contact-aided compliant mechanism called a twist compliant mechanism (TCM) is presented in this paper. This mechanism has nonlinear stiffness when it is twisted in both directions along its axis. The inner core of the mechanism is primarily responsible for its flexibility in one twisting direction. The contact surfaces of the cross-members and compliant sectors are primarily responsible for its high stiffness in the opposite direction. A desired twist angle in a given direction can be achieved by tailoring the stiffness of a TCM. The stiffness of a compliant twist mechanism can be tailored by varying thickness of its cross-members, thickness of the core and thickness of its sectors. A multi-objective optimization problem with three objective functions is proposed in this paper, and used to design an optimal TCM with desired twist angle. The objective functions are to minimize the mass and maximum von-Mises stress observed, while minimizing or maximizing the twist angles under specific loading conditions. The multi-objective optimization problem proposed in this paper is solved for an ornithopter flight research platform as a case study, with the goal of using the TCM to achieve passive twisting of the wing during upstroke, while keeping the wing fully extended and rigid during the downstroke. Prototype TCMs have been fabricated using 3D printing and tested. Testing results are also presented in this paper.

  10. Tool Neck Geometry Design to Improve Stiffness of Micro Endmills

    NARCIS (Netherlands)

    Li, P.; Rozing, M.; Oosterling, J.A.J.; Hoogstrate, A.M.; Langen, H.H.

    2008-01-01

    Due to the scaling effect, micro endmills have low stiffness in nature, which will result in lose of form accuracy in workpiece and vibration of micro tools during micromilling process. Through analytical modeling, it is found that the neck geometry of the micro endmill has a big influence on the to

  11. Torsional stiffness degradation and aerostatic divergence of suspension bridge decks

    Science.gov (United States)

    Zhang, Z. T.; Ge, Y. J.; Yang, Y. X.

    2013-07-01

    The mechanism of aerostatic torsional divergence (ATD) of long-span suspension bridges is investigated. A theoretical analysis on the basis of a generalized model is presented, showing that the vertical motion of a bridge deck is crucial to the torsional stiffness of the whole suspended system, and that the vertical motion of either cable with a magnitude beyond a certain threshold could result in a sudden degradation of the torsional stiffness of the system. This vertical motion-induced degradation of stiffness is recognized as the main reason for the ATD. Long-span suspension bridges are susceptible to such a type of divergence, especially when they are immersed in turbulent wind fields. The divergences that occur in turbulent wind fields differ significantly from those in smooth wind fields, and the difference is well explained by the generalized model that the loosening of any one cable could result in the vanishing of the part of stiffness provided by the whole cable system. The mechanism revealed in this paper leads to a definition of the critical wind speed of the ATD in a turbulent flow; that is, the one resulting in a vertical motion so large as to loosen either cable to a stressless state. Numerical results from the nonlinear finite-element (FE) analysis of the Xihoumen suspension bridge, in conjunction with observations from wind tunnel tests on an aero-elastic full bridge model, are in support of the viewpoint presented in this study.

  12. Substrate stiffness affects skeletal myoblast differentiation in vitro

    Science.gov (United States)

    Romanazzo, Sara; Forte, Giancarlo; Ebara, Mitsuhiro; Uto, Koichiro; Pagliari, Stefania; Aoyagi, Takao; Traversa, Enrico; Taniguchi, Akiyoshi

    2012-12-01

    To maximize the therapeutic efficacy of cardiac muscle constructs produced by stem cells and tissue engineering protocols, suitable scaffolds should be designed to recapitulate all the characteristics of native muscle and mimic the microenvironment encountered by cells in vivo. Moreover, so not to interfere with cardiac contractility, the scaffold should be deformable enough to withstand muscle contraction. Recently, it was suggested that the mechanical properties of scaffolds can interfere with stem/progenitor cell functions, and thus careful consideration is required when choosing polymers for targeted applications. In this study, cross-linked poly-ɛ-caprolactone membranes having similar chemical composition and controlled stiffness in a supra-physiological range were challenged with two sources of myoblasts to evaluate the suitability of substrates with different stiffness for cell adhesion, proliferation and differentiation. Furthermore, muscle-specific and non-related feeder layers were prepared on stiff surfaces to reveal the contribution of biological and mechanical cues to skeletal muscle progenitor differentiation. We demonstrated that substrate stiffness does affect myogenic differentiation, meaning that softer substrates can promote differentiation and that a muscle-specific feeder layer can improve the degree of maturation in skeletal muscle stem cells.

  13. Evaluation of ground stiffness parameters using continuous surface wave geophysics

    DEFF Research Database (Denmark)

    Gordon, Anne; Foged, Niels

    2000-01-01

    -small-strain stiffness of the ground Gmax. Continuous surface wave geophysics offers a quick, non-intrusive and economical way of making such measurements. This paper reviews the continuous surface wave techniques and evaluates, in engineering terms, the applicability of the method to the site investigation industry....

  14. IMPACT OF OVERHEAT ON DISABLED SWIMMERS’ SKELETAL MUSCLE STIFFNESS

    Directory of Open Access Journals (Sweden)

    Prystupa Tetyana

    2014-04-01

    Full Text Available Contemporary athletic recovery involves the range of treatments combined with training and restitution processes and are designed to optimize rest as well as minimize the effects of sports overstrain. Sportsmen benefit enormously from recovery treatments during both preparation and competition phases as they help remove frequent pathogenic pre-start conditions which could reduce work capacity and affect adversely results achieved. Purpose: The paper is aimed to specify the impact of overheat on easing the stiffness of disabled sportspeople’s biceps muscle of arm and the central part of the deltoid muscle. It has been assumed that overheating in a Finnish sauna will facilitate muscle condition and recovery of a swimmer’s body. Material: The research involved 20 disabled swimmers - 10 competitors based in the Start sports club in Kalisz and 10 contestants based in Start sports club in Wroclaw. The Tonus-1 myotonometer was used to measure the stiffness of biceps muscle of arm (biceps brachii and the central part of the deltoid muscle (deltoideus - pars acromialic. The research was carried out in two stages: training mesocycle with no recovery and training mesocycle with recovery. The mesocycles comprised three one-week-long microcycles each. Results: The research proved the overheating to ease rest muscle stiffness . Conclusions: The upshot of the discussion was that the Finnish sauna has a tonic effect on a disable swimmer’s body. Reduction of post work-out muscle stiffness will facilitate effective recovery and bring forward next training activities.

  15. Riparian Sediment Delivery Ratio: Stiff Diagrams and Artifical Neural Networks

    Science.gov (United States)

    Various methods are used to estimate sediment transport through riparian buffers and grass jilters with the sediment delivery ratio having been the most widely applied. The U.S. Forest Service developed a sediment delivery ratio using the stiff diagram and a logistic curve to int...

  16. The effects of cycling shoe stiffness on forefoot pressure.

    Science.gov (United States)

    Jarboe, Nathan Edward; Quesada, Peter M

    2003-10-01

    Plantar pressure data were recorded in two different shoe types to determine the effect of cycling shoe stiffness on peak plantar forefoot pressure in cyclists. Two pairs of shoes of the same size and manufacturer, identical except for outsole material and stiffness, were tested. Shoe stiffness measurements were collected under controlled conditions and in two different configurations using a dynamic hydraulic tensile testing machine. Measurements of plantar pressure were done using Pedar capacitive-based sensor insoles while subjects pedaled in a seated position at a controlled power output. Power output was set at a constant value of 400 W across all subjects by a magnetic resistance trainer unit. The pressure distribution in carbon-fiber-composite shoes during cycling was compared to cycling shoes made with plastic soles. Carbon fiber shoes presented stiffness values 42% and 550% higher than plastic shoes in longitudinal bending and three-point bending, respectively. The shoes made with carbon fiber produced peak plantar pressures 18% higher than those of plastic design (121 kPa vs. 103 kPa, p = .005). Competitive or professional cyclists suffering from metatarsalgia or ischemia should be especially careful when using carbon fiber cycling shoes because the shoes increase peak plantar pressure, which may aggravate these foot conditions.

  17. How crouch gait can dynamically induce stiff-knee gait.

    Science.gov (United States)

    van der Krogt, Marjolein M; Bregman, Daan J J; Wisse, Martijn; Doorenbosch, Caroline A M; Harlaar, Jaap; Collins, Steven H

    2010-04-01

    Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on excessive knee muscle activity during (pre)swing, but the passive dynamics of the limbs may also have an important effect. To examine the effects of a crouched posture on swing knee flexion, we developed a forward-dynamic model of human walking with a passive swing knee, capable of stable cyclic walking for a range of stance knee crouch angles. As crouch angle during stance was increased, the knee naturally flexed much less during swing, resulting in a 'stiff-knee' gait pattern and reduced foot clearance. Reduced swing knee flexion was primarily due to altered gravitational moments around the joints during initial swing. We also considered the effects of increased push-off strength and swing hip flexion torque, which both increased swing knee flexion, but the effect of crouch angle was dominant. These findings demonstrate that decreased knee flexion during swing can occur purely as the dynamical result of crouch, rather than from altered muscle function or pathoneurological control alone.

  18. Stiffness and hysteresis properties of some prosthetic feet

    NARCIS (Netherlands)

    Jaarsveld, van H.W.L.; Grootenboer, H.J.; Vries, de J.; Koopman, H.F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hyst

  19. Evaluation of ground stiffness parameters using continuous surface wave geophysics

    DEFF Research Database (Denmark)

    Gordon, Anne; Foged, Niels

    2000-01-01

    -small-strain stiffness of the ground Gmax. Continuous surface wave geophysics offers a quick, non-intrusive and economical way of making such measurements. This paper reviews the continuous surface wave techniques and evaluates, in engineering terms, the applicability of the method to the site investigation industry....

  20. Extracellular matrix stiffness and architecture govern intracellular rheology in cancer.

    Science.gov (United States)

    Baker, Erin L; Bonnecaze, Roger T; Zaman, Muhammad H

    2009-08-19

    Little is known about the complex interplay between the extracellular mechanical environment and the mechanical properties that characterize the dynamic intracellular environment. To elucidate this relationship in cancer, we probe the intracellular environment using particle-tracking microrheology. In three-dimensional (3D) matrices, intracellular effective creep compliance of prostate cancer cells is shown to increase with increasing extracellular matrix (ECM) stiffness, whereas modulating ECM stiffness does not significantly affect the intracellular mechanical state when cells are attached to two-dimensional (2D) matrices. Switching from 2D to 3D matrices induces an order-of-magnitude shift in intracellular effective creep compliance and apparent elastic modulus. However, for a given matrix stiffness, partial blocking of beta1 integrins mitigates the shift in intracellular mechanical state that is invoked by switching from a 2D to 3D matrix architecture. This finding suggests that the increased cell-matrix engagement inherent to a 3D matrix architecture may contribute to differences observed in viscoelastic properties between cells attached to 2D matrices and cells embedded within 3D matrices. In total, our observations show that ECM stiffness and architecture can strongly influence the intracellular mechanical state of cancer cells.

  1. Extracellular Matrix Stiffness and Architecture Govern Intracellular Rheology in Cancer

    National Research Council Canada - National Science Library

    Baker, Erin L; Bonnecaze, Roger T; Zaman, Muhammad H

    2009-01-01

    ... in revealing biochemical mechanisms that underlie diseases such as cancer ( 7 ), adequate quantitative characterization of associated cellular mechanical properties remains largely incomplete. It is known that cancerous tissue (cancer cells embedded within the ECM) exhibits elevated stiffness compared to normal tissue ( 8 ) and that the critical ...

  2. Social Inclusion of Senior Citizens by a Teleoperated Android

    DEFF Research Database (Denmark)

    Yamazaki, Ryuji; Nishio, Shuichi; Ishiguro, Hiroshi

    As populations continue to age, there is a growing need for assistive technologies that help senior citizens maintain their autonomy and enjoy their lives. We explore the potential of teleoperated androids, which are embodied telecommunication media with humanlike appearances. Our exploratory study...... focused on the social aspects of Telenoid, a teleoperated android designed as a minimalistic human, which might facilitate communica- tion between senior citizens and its operators. We con- ducted cross-cultural field trials in Japan and Denmark by introducing Telenoid into care facilities and the pri...

  3. Methodology for vocational psychodiagnostics of senior schoolchildren using information technologies

    Science.gov (United States)

    Bogdanovskaya, I. M.; Kosheleva, A. N.; Kiselev, P. B.; Davydova, Yu. A.

    2017-01-01

    The article identifies the role and main problems of vocational psychodiagnostics in modern socio-cultural conditions. It analyzes the potentials of information technologies in vocational psychodiagnostics of senior schoolchildren. The article describes the theoretical and methodological grounds, content and diagnostic potentials of the computerized method in vocational psychodiagnostics. The computerized method includes three blocks of sub-tests to identify intellectual potential, personal qualities, professional interests and values, career orientations, as well as subtests to analyze the specific life experience of senior schoolchildren. The results of diagnostics allow developing an integrated psychodiagnostic conclusion with recommendations. The article contains options of software architecture for the given method.

  4. Citation ranking versus peer evaluation of senior faculty research performance

    DEFF Research Database (Denmark)

    Meho, Lokman I.; Sonnenwald, Diane H.

    2000-01-01

    The purpose of this study is to analyze the relationship between citation ranking and peer evaluation in assessing senior faculty research performance. Other studies typically derive their peer evaluation data directly from referees, often in the form of ranking. This study uses two additional...... of research appear to be needed to effectively evaluate senior scholars whose performance ranks relatively in the middle. Citation content analysis data did appear to give some specific and important insights into the quality of research of these middle performers, however, further analysis and research...

  5. Interpersonal behaviour in senior high school biology classes

    Science.gov (United States)

    Fisher, Darrell; Henderson, David; Fraser, Barry

    1995-06-01

    This article describes the first use of the Questionnaire on Teacher Interaction in senior biology classes and describes students' perceptions of their interpersonal relationships with their teachers in the classroom environment. The article also describes associations between students' perceptions of interpersonal relationships with their teachers and student outcomes. The study confirmed the reliability and validity of the QTI when used in senior secondary biology classes. Generally, the dimensions of the QTI were found to be significantly associated with student attitude scores. In particular, students' attitude scores were higher in classrooms in which students perceived greater leadership, helpful/friendly, and understanding behaviours in their teachers.

  6. Social Inclusion of Senior Citizens by a Teleoperated Android

    DEFF Research Database (Denmark)

    Yamazaki, Ryuji; Nishio, Shuichi; Ishiguro, Hiroshi

    As populations continue to age, there is a growing need for assistive technologies that help senior citizens maintain their autonomy and enjoy their lives. We explore the potential of teleoperated androids, which are embodied telecommunication media with humanlike appearances. Our exploratory study...... focused on the social aspects of Telenoid, a teleoperated android designed as a minimalistic human, which might facilitate communica- tion between senior citizens and its operators. We con- ducted cross-cultural field trials in Japan and Denmark by introducing Telenoid into care facilities and the pri...

  7. Arterial Stiffness in Nonhypertensive Type 2 Diabetes Patients in Ghana

    Science.gov (United States)

    Antwi, Daniel A.; Gyan, Ben

    2016-01-01

    Background. Increased arterial stiffness is an independent cardiovascular risk factor in diabetes patients and general population. However, the contribution of diabetes to arterial stiffness is often masked by coexistent obesity and hypertension. In this study, we assessed arterial stiffness in nonhypertensive, nonobese type 2 diabetes (T2DM) patients in Ghana. Methods. In case-control design, 166 nonhypertensive, nonobese participants, comprising 96 T2DM patients and 70 nondiabetes controls, were recruited. Peripheral and central blood pressure (BP) indices were measured, and arterial stiffness was assessed as aortic pulse wave velocity (PWVao), augmentation index (AIx), cardioankle vascular index (CAVI), and heart-ankle pulse wave velocity (haPWV). Results. With similar peripheral and central BP indices, T2DM patients had higher PWVao (8.3 ± 1 versus 7.8 ± 1.3, p = 0.044) and CAVI (7.9 ± 1.2 versus 6.9 ± 0.7, p = 0.021) than nondiabetic control. AIx and haPWV were similar between T2DM and nondiabetic controls. Multiple regression models showed that, in the entire study participants, the major determinants of PWVao were diabetes status, age, gender, systolic BP, and previous smoking status (β = 0.22, 0.36, 0.48, 0.21, and 0.25, resp.; all p < 0.05); the determinants of CAVI were diabetes status, age, BMI, heart rate, HbA1c, total cholesterol, HDL cholesterol, and previous smoking status (β = 0.21, 0.38, 0.2, 0.18, 0.24. 0.2, −0.19, and 0.2, resp.; all p < 0.05). Conclusion. Our findings suggest that nonhypertensive, nonobese T2DM patients have increased arterial stiffness without appreciable increase in peripheral and central pressure indices.

  8. Stiffness characteristics of splints for fixation of traumatized teeth.

    Science.gov (United States)

    Ben Hassan, Meshari W; Andersson, Lars; Lucas, Peter W

    2016-04-01

    Traumatic dental injuries (TDI) are treated by repositioning and splinting. Ideally, injured teeth should possess some mobility for optimal periodontal and pulp healing. Splints should be easy to apply in emergencies, affordable, and esthetically acceptable. The aims were to compare some clinically used splints with regard to stiffness (measured in Nm(-1)), esthetics, cost, and ease of application. Six splints were applied to dental models using an acid-etched bonding technique. One central incisor was adjusted to give 1 mm of horizontal movement at the incisal edge. The mobilized tooth was then connected to adjacent teeth with either twistflex wire (TF), titanium trauma splint (TTS), single (SFG) and double fiberglass (DFG), nylon (fishing) line (FL), or power chain (PC). A horizontal force was then gradually applied to the incisor in a standardized manner with a spherical probe (1.65 mm radius), monitoring force with a 50N load cell and displacement with a linear variable differential transformer (LVDT). Signals were amplified, converted digitally (14-bit analog-to-digital converter), and displayed in real time to show the splint stiffness. Splints were also ranked with regard to esthetics, application time needed, and ease of application cost. FL and PC were the least stiff, averaging 5.7 and 6.3 Nm(-1), respectively. TTS averaged 6.9 Nm(-1), while SFG and TF averaged 18.5 and 18.4 Nm(-1), respectively. DFG was the stiffest, averaging 24.3 Nm(-1). PC and SFG were the fastest to apply. FL showed the best esthetic score, followed by TTS and PC. TTS was the most expensive splint, while FL, PC, SFG, DFG, and TF showed similar costs. Of these TDI splints, DFG should be avoided for flexible splinting because it is too stiff. PC may be an interesting novel alternative, affording sufficient mobility due to its low stiffness. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Nonsteroidal antiinflammatory drugs are associated with increased aortic stiffness

    Directory of Open Access Journals (Sweden)

    Martin Claridge

    2005-07-01

    Full Text Available Martin Claridge1, Simon Hobbs1, Clive Quick2, Nick Day3, Andrew Bradbury1, Teun Wilmink11Department of Vascular Surgery, University of Birmingham, Birmingham Heartlands Hospital Birmingham, UK; 2Department of Surgery, Hinchingbrooke Hospital, Huntingdon, UK; 3Department of Epidemiology and Biostatistics, University of Cambridge, Cambridge, UKObjectives: Nonsteroidal antiinflammatory drugs (NSAIDS have been shown to retard aneurysm growth in animal models. In vitro studies have shown an inhibitory effect of NSAIDS on matrix metalloproteinase-9, interleukin-1β, and IL-6 mediated arterial wall elastolysis. The aim of this study was to investigate the effects of NSAIDs on arterial stiffness, a surrogate marker of elastolysis.Methods: 447 subjects enrolled in a community-based abdominal aortic aneurysm (AAA screening program were assessed for age, blood pressure, smoking status, and drug history. Aortic diameter and stiffness were measured by M-Mode ultrasound. The concentration of the amino-terminal propeptide of type III procollagen was used as a proxy measurement of type III collagen turnover.Results: NSAID ingestion was significantly (p = 0.006 associated with increased aortic wall stiffness after adjusting for age, aortic diameter, blood pressure, and smoking status. No such effect was seen for β-blockers, calcium channel antagonists, nitrates, angiotensin-converting enzyme inhibitors, diuretics, or antiplatelet agents.Discussion: These novel data show that NSAIDS are associated with increased aortic stiffness, possibly through the effects of cytokine mediated elastolysis. This in turn may prevent aortic expansion and the development of AAA.Keywords: nonsteroidal antiinflammatory drugs, abdominal aortic aneurysm, aortic stiffness, elastolysis

  10. Acute exercise modifies titin phosphorylation and increases cardiac myofilament stiffness

    Directory of Open Access Journals (Sweden)

    Anna Eliane Müller

    2014-11-01

    Full Text Available Titin-based myofilament stiffness is largely modulated by phosphorylation of its elastic I-band regions N2-Bus (decreases passive stiffness, PT and PEVK (increases PT. Here, we tested the hypothesis that acute exercise changes titin phosphorylation and modifies myofilament stiffness. Adult rats were exercised on a treadmill for 15min, untrained animals served as controls. Titin phosphorylation was determined by Western blot analysis using phosphospecific antibodies to Ser4099 and Ser4010 in the N2-Bus region (PKG and PKA-dependent. respectively, and to Ser11878 and Ser 12022 in the PEVK region (PKCα and CaMKIIδ-dependent, respectively. Passive tension was determined by step-wise stretching of isolated skinned cardiomyocytes to sarcomere length ranging from 1.9-2.4µm and showed a significantly increased PT from exercised samples, compared to controls. In cardiac samples titin N2-Bus phosphorylation was significantly decreased by 40% at Ser4099, however, no significant changes were observed at Ser4010. PEVK phosphorylation at Ser11878 was significantly increased, which is probably mediated by the observed exercise-induced increase in PKCα activity. Interestingly, relative phosphorylation of Ser12022 was substantially decreased in the exercised samples. Surprisingly, in skeletal samples from acutely exercised animals we detected a significant decrease in PEVK phosphorylation at Ser11878 and an increase in Ser12022 phosphorylation; however, PKCα activity remained unchanged. In summary, our data show that a single exercise bout of 15 min affects titin domain phosphorylation and titin-based myocyte stiffness with obviously divergent effects in cardiac and skeletal muscle tissues. The observed changes in titin stiffness could play an important role in adapting the passive and active properties of the myocardium and the skeletal muscle to increased physical activity.

  11. Pressure-dependence of arterial stiffness: potential clinical implications.

    Science.gov (United States)

    Spronck, Bart; Heusinkveld, Maarten H G; Vanmolkot, Floris H; Roodt, Jos Op 't; Hermeling, Evelien; Delhaas, Tammo; Kroon, Abraham A; Reesink, Koen D

    2015-02-01

    Arterial stiffness measures such as pulse wave velocity (PWV) have a known dependence on actual blood pressure, requiring consideration in cardiovascular risk assessment and management. Given the impact of ageing on arterial wall structure, the pressure-dependence of PWV may vary with age. Using a noninvasive model-based approach, combining carotid artery echo-tracking and tonometry waveforms, we obtained pressure-area curves in 23 hypertensive patients at baseline and after 3 months of antihypertensive treatment. We predicted the follow-up PWV decrease using modelled baseline curves and follow-up pressures. In addition, on the basis of these curves, we estimated PWV values for two age groups (mean ages 41 and 64 years) at predefined hypertensive (160/90 mmHg) and normotensive (120/80 mmHg) pressure ranges. Follow-up measurements showed a near 1 m/s decrease in carotid PWV when compared with baseline, which fully agreed with our model-prediction given the roughly 10 mmHg decrease in diastolic pressure. The stiffness-blood pressure-age pattern was in close agreement with corresponding data from the 'Reference Values for Arterial Stiffness' study, linking the physical and empirical bases of our findings. Our study demonstrates that the innate pressure-dependence of arterial stiffness may have implications for the clinical use of arterial stiffness measurements, both in risk assessment and in treatment monitoring of individual patients. We propose a number of clinically feasible approaches to account for the blood pressure effect on PWV measurements.

  12. Impact testing of the residual limb: System response to changes in prosthetic stiffness

    Directory of Open Access Journals (Sweden)

    Erin Boutwell, PhD

    2016-04-01

    Full Text Available Currently, it is unknown whether changing prosthetic limb stiffness affects total limb stiffness and/or influences the shock absorption of an individual with transtibial amputation. The hypotheses tested within this study are that a decrease in longitudinal prosthetic stiffness will produce (1 reduced total limb stiffness and (2 reduced magnitude of peak impact forces and increased time delay to peak force. Fourteen subjects with a transtibial amputation participated in this study. Prosthetic stiffness was modified by means of a shock-absorbing pylon that provides reduced longitudinal stiffness through compression of a helical spring within the pylon. A sudden loading evaluation device was built to examine changes in limb loading mechanics during a sudden impact event. No significant change was found in the peak force magnitude or timing of the peak force between prosthetic limb stiffness conditions. Total limb stiffness estimates ranged from 14.9 to 17.9 kN/m but were not significantly different between conditions. Thus, the prosthetic-side total limb stiffness was unaffected by changes in prosthetic limb stiffness. The insensitivity of the total limb stiffness to prosthetic stiffness may be explained by the mechanical characteristics (i.e., stiffness and damping of the anatomical tissue within the residual limb.

  13. Simulated and experimental studies on a high-static-low-dynamic stiffness isolator using magnetic negative stiffness spring

    Science.gov (United States)

    Dong, Guangxu; Zhang, Xinong; Xie, Shilin; Yan, Bo; Luo, Yajun

    2017-03-01

    For the purpose of isolating the low frequency vibration, a magnetic vibration isolator with the feature of high-static-low-dynamic stiffness (HSLDS) is developed in this paper, which is constructed by combining a magnetic negative stiffness spring (MNSS) with a spiral flexure spring (SFS) in parallel. The MNSS comprises three magnetic rings configured in attraction and is utilized to reduce the resonant frequency of the isolator. Then an analytical expression of magnetic negative stiffness (MNS) of the MNSS is deduced in terms of the current model, and an approximation to the MNS is further sought. To support the object, the axial positive stiffness of SFSs, which can behave with a smaller static deformation if a specified weight is applied, is analyzed with finite element method (FEM). After that, the governing equation of the isolator is established and solved via harmonic balance method (HBM). Finally, an experimental prototype is developed and tested. The experimental results demonstrate that the MNSS can reduce the resonant frequency of the isolator to expand the isolation frequency band to low frequency range; and the theoretical calculations and experimental results shows a good agreement.

  14. Skinfold thickness as a predictor of arterial stiffness: obesity and fatness linked to higher stiffness measurements in hypertensive patients.

    Science.gov (United States)

    Selcuk, Ali; Bulucu, Fatih; Kalafat, Firdevs; Cakar, Mustafa; Demirbas, Seref; Karaman, Murat; Ay, Seyid Ahmet; Saglam, Kenan; Balta, Sevket; Demirkol, Sait; Arslan, Erol

    2013-01-01

    Hypertensive patients have strong evidence of endothelial dysfunction. Some novel endothelial dysfunction parameters such as pulse wave velocity (PWV), augmentation index (AIx), and central aortic pressure (CAP) have been investigated as predictive markers of atherosclerosis. It is well known that obesity has relationships with endothelial dysfunction and atherosclerosis. We aimed to investigate relationships between anthropometric measurements and arterial stiffness parameters in essentially hypertensive patients. The study population included 100 patients (56 females, 44 males) newly or formerly diagnosed as essentially hypertensive in an outpatient clinic. Arterial stiffness measurements, including PWV, AIx, CAP, and body mass index (BMI); waist circumference, hip circumference; waist/hip ratio; and triceps, biceps, subscapular, and suprailiac skinfold thicknesses were also applied to all the study patients. Then, the relationships between BMI, anthropometric measurements, and arterial stiffness parameters were investigated. The mean systolic arterial blood pressure of the study population was 135.85 ± 15.27 mm Hg and the mean diastolic arterial blood pressure of the study population was 84.17 ± 9.58 mm Hg. The parameters such as PWV, AIx, and CAP measured for arterial stiffness had correlations between BMI and different anthropometric measurements. The statistically significant correlations were present between PWV and triceps skinfold thickness (TST) (r = 0.377, P skinfold thickness among these correlations may be used to estimate the carotid-femoral PWV, which is an indicator of subclinical organ damage due to hypertension.

  15. The biomechanical demands of standing yoga poses in seniors: The Yoga empowers seniors study (YESS

    Directory of Open Access Journals (Sweden)

    Wang Man-Ying

    2013-01-01

    Full Text Available Abstract Background The number of older adults participating in yoga has increased dramatically in recent years; yet, the physical demands associated with yoga performance have not been reported. The primary aim of the Yoga Empowers Seniors Study (YESS was to use biomechanical methods to quantify the physical demands associated with the performance of 7 commonly-practiced standing yoga poses in older adults. Methods 20 ambulatory older adults (70.7 + − 3.8 yrs attended 2 weekly 60-minute Hatha yoga classes for 32 weeks. The lower-extremity net joint moments of force (JMOFs, were obtained during the performance of the following poses: Chair, Wall Plank, Tree, Warrior II, Side Stretch, Crescent, and One-Legged Balance. Repeated-measure ANOVA and Tukey’s post-hoc tests were used to identify differences in JMOFs among the poses. Electromyographic analysis was used to support the JMOF findings. Results There was a significant main effect for pose, at the ankle, knee and hip, in the frontal and sagittal planes (p = 0.00 – 0.03. The Crescent, Chair, Warrior II, and One-legged Balance poses generated the greatest average support moments. Side Stretch generated the greatest average hip extensor and knee flexor JMOFs. Crescent placed the highest demands on the hip flexors and knee extensors. All of the poses produced ankle plantar-flexor JMOFs. In the frontal plane, the Tree generated the greatest average hip and knee abductor JMOFs; whereas Warrior II generated the greatest average hip and knee adductor JMOFs. Warrior II and One-legged Balance induced the largest average ankle evertor and invertor JMOFs, respectively. The electromyographic findings were consistent with the JMOF results. Conclusions Musculoskeletal demand varied significantly across the different poses. These findings may be used to guide the design of evidence-based yoga interventions that address individual-specific training and rehabilitation goals in seniors

  16. Seniorer och identitet på Facebook : En studie om seniorers uppfattning och skapande av identitet på Facebook

    OpenAIRE

    Sahlén, Mattias; Volter, Madeleine

    2013-01-01

    The aim of our study was to increase understanding of older people’s views on social media’s and identity by asking the question: How do seniors perceive identity on Facebook? Based on a qualitative approach with written interviews conducted by e-mail, we contacted respondents who had and used a Facebook account. In our study we used categories, such as seniors, identity, Facebook and networking to be able to answer our research question. The result of this study is shown as a description of ...

  17. Stiffness Analysis and Comparison of 3-PPR Planar Parallel Manipulators with Actuation Compliance

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl

    2012-01-01

    In this paper, the stiffness of 3-PPR planar parallel manipulator (PPM) is analyzed with the consideration of nonlinear actuation compliance. The characteristics of the stiffness matrix pertaining to the planar parallel manipulators are analyzed and discussed. Graphic representation...

  18. Dependence of elbow joint stiffness measurements on speed, angle, and muscle contraction level.

    Science.gov (United States)

    Kuxhaus, Laurel; Zeng, Sisi; Robinson, Charles J

    2014-03-21

    Elbow joint stiffness is critical to positioning the hand. Abnormal elbow joint stiffness may affect a person's ability to participate in activities of daily living. In this work, elbow joint stiffness was measured in ten healthy young adults with a device adapted from one previously used to measure stiffness in other joints. Measurements of elbow stiffness involved applying a constant-velocity rotational movement to the elbow and measuring the resultant displacement, torque, and acceleration. Elbow stiffness was then computed using a previously-established model for joint stiffness. Measurements were made at two unique elbow joint angles, two speeds, and two forearm muscle contraction levels. The results indicate that the elbow joint stiffness is significantly affected by both rotational speed and forearm muscle contraction level.

  19. Ursodeoxycholic acid treatment is associated with improvement of liver stiffness in cystic fibrosis patients

    NARCIS (Netherlands)

    van der Feen, Cathelijne; van der Doef, Hubert P. J.; van der Ent, Cornelis K.; Houwen, Roderick H. J.

    2016-01-01

    Background: Ursodeoxycholic acid (UDCA) might prevent progression of cystic fibrosis liver disease, but objective parameters for its effect are lacking. Methods: We used liver stiffness measurements to evaluate the effect of Ursodeoxycholic acid. Results: Paired measurements of liver stiffness were

  20. Specific phobia is a frequent non-motor feature in stiff man syndrome

    OpenAIRE

    Henningsen, P.; Meinck, H

    2003-01-01

    Objective: To investigate systematically the rate and type of phobia in stiff man syndrome and its variants, and to compare patients with stiff man syndrome with and without phobia for sociodemographic and neurological characteristics.