Comparative study of four retentive anchor systems for implant supported overdentures--retention force changes

OBJECTIVES: Wear of attachments leads to a loss of retention and potentially reduces the function of complete dentures. This study evaluated the retention force changes of different prefabricated attachment systems for implant-supported overdentures to estimate the wear constancy and applicability in clinical practice. METHODS: Four prefabricated attachment systems were tested [Group SG: retentive ball attachment (Straumann, Switzerland) with gold matrix, Group ST: retentive ball attachment (Straumann, Switzerland) with titanium spring matrix, Group IB: UNOR i-Ball with Ecco matrix (UNOR, Switzerland) and Group IMZ: IMZ-TwinPlus ball attachment with gold matrix (DENTSPLY Friadent, Germany)]. Ten samples of each system were subjected to 10,000 insertion-separation cycles. RESULTS: Results showed that all types of attachments showed wear, which led to a loss of retention force after an initial increase at the beginning of the wear simulation. Attachments with a plastic retention insert or gold matrices underwent the smallest changes in retention force. The titanium spring system showed the largest changes in retention force and a greater variation between the different cycles and specimen. This behaviour is probably caused by a large fitting tolerance of the titanium spring. CONCLUSIONS: Attachment systems which possess a male and female component of different material composition are preferable. They show smaller changes in the retention force. For retention force increase and wear compensation, an attachment system should be adjustable.

Who has really paid for the Reconstruction of East Germany? Expected and Realized Returns on Real Estate Investments in East and West Germany in the 1990s

We evaluate the profitability of investments in residential property in Germany after unification with a focus on the comparison of East and West Germany. Calculations are carried out for (1) the after-tax return an investor might have expected at the beginning of the 1990s, and (2) the after-tax return that has been realized ten years after. We compare a set of statistical data for investments in fifty major cities by using complete financial budgeting. The results show that tax subsidies could not always protect investors from losing money, but they have boosted realized returns after tax considerably. Therefore, it was indeed the taxpayers, not the investors, who have borne the cost of reconstructing East Germany.

A General Solution Framework for Component-Commonality Problems

Component commonality - the use of the same version of a component across multiple products - is being increasingly considered as a promising way to offer high external variety while retaining low internal variety in operations. However, increasing commonality has both positive and negative cost effects, so that optimization approaches are required to identify an optimal commonality level. As components influence to a greater or lesser extent nearly every process step along the supply chain, it is not surprising that a multitude of diverging commonality problems is being investigated in literature, each of which are developing a specific algorithm designed for the respective commonality problem being considered. The paper on hand aims at a general framework which is flexible and efficient enough to be applied to a wide range of commonality problems. Such a procedure based on a two-stage graph approach is presented and tested. Finally, flexibility of the procedure is shown by customizing the framework to account for different types of commonality problems.

Magnetic resonance imaging anatomy of the normal equine larynx and pharynx

The purpose of the present study was to describe normal magnetic resonance (MR) imaging anatomy of the equine larynx and pharynx and to present the optimal protocol, sequences, and possible limitations of this examination technique. Using a 0.3 T unit, the laryngeal and pharyngeal regions was imaged in two horses. The protocol consisted of sagittal and transverse T2-weighted (T2w) fast spin echo, transverse T1-weighted (T1w) spin echo, and dorsal high-resolution T1w gradient echo (both pre- and postcontrast enhancement) sequences. Euthanasia was performed at the end of the imaging procedure. Macroscopic anatomy of the cadaver sections were compared with the MR images in transverse, midsagittal, and parasagittal planes. There was good differentiation of anatomic structures, including soft tissues. The laryngeal cartilages, hyoid apparatus, and upper airway muscle groups with their attachments could be clearly identified. However, it was not always possible to delineate individual muscles in each plane. Most useful were both T2w and T1w transverse sequences. Intravenous application of contrast medium was helpful to identify blood vessels. The MR images corresponded with the macroscopic anatomy of cadaver sections.

A novel technique, dynamic intraligamentary stabilization creates optimal conditions for primary ACL healing: A preliminary biomechanical study

BACKGROUND Anterior cruciate ligament (ACL) rupture is a common lesion. Current treatment emphasizes arthroscopic ACL reconstruction via a graft, although this approach is associated with potential drawbacks. A new method of dynamic intraligamentary stabilization (DIS) was subjected to biomechanical analysis to determine whether it provides the necessary knee stability for optimal ACL healing. METHODS Six human knees from cadavers were harvested. The patellar tendon, joint capsule and all muscular attachments to the tibia and femur were removed, leaving the collateral and the cruciate ligaments intact. The knees were stabilized and the ACL kinematics analyzed. Anterior-posterior (AP) stability measurements evaluated the knees in the following conditions: (i) intact ACL, (ii) ACL rupture, (iii) ACL rupture with primary stabilization, (iv) primary stabilization after 50 motion cycles, (v) ACL rupture with DIS, and (vi) DIS after 50 motion cycles. RESULTS After primary suture stabilization, average AP laxity was 3.2mm, which increased to an average of 11.26mm after 50 movement cycles. With primary ACL stabilization using DIS, however, average laxity values were consistently lower than those of the intact ligament, increasing from an initial AP laxity of 3.00mm to just 3.2mm after 50 movement cycles. CONCLUSIONS Dynamic intraligamentary stabilization established and maintained close contact between the two ends of the ruptured ACL, thus ensuring optimal conditions for potential healing after primary reconstruction. The present ex vivo findings show that the DIS technique is able to restore AP stability of the knee.

Transnational Migration and Cross-border Mobility in the Serbian-Hungarian Border Region

The study is aiming to present migrant groups in the Serbian-Hungarian border region which are playing a role in forming transnational migration, ransnational networks and transnational spaces. Transnational migrants are using material, cultural, social and symbolical capital in various forms. The everyday activities of the people as well as their mobility, emotional attachments, and economic relationships have contributed to a transnational region the cross-border contacts in the last century were always present, even in spite of political and historical changes, only their intensity, political charge and tension has been changing. The asymmetries defining the border region has been reflected in different directions, places, time and in different volume. In this specially built and constantly reorganising scope, people who were living their everyday life have tried to use the differences for their benefit, and to improve their possibilities. With their transnational lifestyles and cross-border networks, they substantially contribute to the stability and prosperity of the cross-border region.

Cultural Legacies and Political Preferences: The Failure of Separatism in the Swiss Jura

The study of secession generally stresses the causal influence of cultural identities, political preferences, or ecological factors. Whereas these different views are often considered to be mutually exclusive, this paper proposes a two-stage model in which they are complementary. We posit that cultural identities matter for explaining secessionism, but not because of primordial attachments. Rather, religious and linguistic groups matter because their members are imbued with cultural legacies that lead to distinct political preferences – in this case preferences over welfare statism. Further, ecological constraints such as geography and topography affect social interaction with like-minded individuals. On the basis of both these political preferences and ecological constraints, individuals then make rational choices about the desirability of secession. Instrumental considerations are therefore crucial in explaining the decision to secede, but not in a conventional pocketbook manner. To examine this theory, we analyze the 2013 referendum on the secession of the Jura Bernois region from the Canton of Berne in Switzerland, using municipal level census and referendum data. The results lend support to the theory and suggest one way in which the politics of identity, based on factors like language and religion, can be fused with the politics of interest (preferences for more or less state intervention into the polity and economy) to better understand group behavior.

IDENTIFICATION AND ANALYSIS OF A NOVEL ROLE FOR THE TOUSLED-LIKE KINASE IN REGULATING MITOTIC SPINDLE DYNAMICS

Deregulation of kinase activity is one example of how cells become cancerous by evading evolutionary constraints. The Tousled kinase (Tsl) was initially identified in Arabidopsis thaliana as a developmentally important kinase. There are two mammalian orthologues of Tsl and one orthologue in C. elegans, TLK-1, which is essential for embryonic viability and germ cell development. Depletion of TLK-1 leads to embryonic arrest large, distended nuclei, and ultimately embryonic lethality. Prior to terminal arrest, TLK-1-depleted embryos undergo aberrant mitoses characterized by poor metaphase chromosome alignment, delayed mitotic progression, lagging chromosomes, and supernumerary centrosomes. I discovered an unanticipated requirement for TLK-1 in mitotic spindle assembly and positioning. Normally, in the newly-fertilized zygote (P0) the maternal pronucleus migrates toward the paternal pronucleus at the posterior end of the embryo. After pronuclear meeting, the pronuclear-centrosome complex rotates 90° during centration to align on the anteroposterior axis followed by nuclear envelope breakdown (NEBD). However, in TLK-1-depleted P0 embryos, the centrosome-pronuclear complex rotation is significantly delayed with respect to NEBD and chromosome congression, Additionally, centrosome positions over time in tlk-1(RNAi) early embryos revealed a defect in posterior centrosome positioning during spindle-pronuclear centration, and 4D analysis of centrosome positions and movement in newly fertilized embryos showed aberrant centrosome dynamics in TLK-1-depleted embryos. Several mechanisms contribute to spindle rotation, one of which is the anchoring of astral microtubules to the cell cortex. Attachment of these microtubules to the cortices is thought to confer the necessary stability and forces in order to rotate the centrosome-pronuclear complex in a timely fashion. Analysis of a microtubule end-binding protein revealed that TLK-1-depleted embryos exhibit a more stochastic distribution of microtubule growth toward the cell cortices, and the types of microtubule attachments appear to differ from wild-type embryos. Additionally, fewer astral microtubules are in the vicinity of the cell cortex, thus suggesting that the delayed spindle rotation could be in part due to a lack of appropriate microtubule attachments to the cell cortex. Together with recently published biochemical data revealing the Tousled-like kinases associate with components of the dynein microtubule motor complex in humans, these data suggest that Tousled-like kinases play an important role in mitotic spindle assembly and positioning.

Phosphorus and Potassium Rates and Placement Methods for Corn and Soybean Managed with No-till or Tillage

No-till management for corn and soybean results in little or no incorporation of crop residues and fertilizer with soil. Subsurface banding phosphorus (P) and potassium (K) fertilizers with planter attachments could be more effective than broadcast fertilization, because in no-till with broadcast fertilizer, both nutrients accumulate at or near the soil surface. A long-term study was initiated in 1994 at the ISU Northwest Research Farm to evaluate P and K fertilizer placement for corn and soybean managed with no-till and chiselplow tillage.

Comerciantes y exploradores yerbateros del Altoparaná. La conformación de una “élite local” en Misiones con intereses regionales. En: LaRivada, V. 1, n° 1

Un clima de inestabilidad política y rivalidades se desarrollaba sobre el espacio misionero entre los Estados nacionales en formación hasta el desenlace de la Guerra de la Triple Alianza. Ello posicionó a Trincheras de San José como un sitio estratégico en la frontera en disputa desde los primeros años de la formación del poblado hasta la expulsión de los paraguayos en 1867. Desde allí se organizaron comitivas exploradoras que partieron en busca de yerba mate para abastecer primero a las necesidades de las tropas aliadas y en los primeros años de posguerra al incipiente mercado argentino. La actividad yerbatera estimuló el comercio y la acumulación de capitales en los años posteriores y dio origen a la generación de una “élite local” cuyos rasgos estuvieron asociados fundamentalmente a la actividad económica de la extracción de la yerba mate en la región y la circulación de sus miembros en los ámbitos del poder político local.

Vivir aquí, vestir allá. Vestidoras transfronterizas. El paso de las vestidoras de difuntos de la Isla Apipé Grande, Corrientes (Argentina), hacia Ayolas (Paraguay). En LaRivada, V. 1, n° 1

El presente trabajo pretende aproximarnos a algunas de las relaciones socio-culturales que se construyen, en el presente etnográfico, entre los habitantes de la Isla Apipé Grande, Corrientes, y los de la localidad de Ayolas, Paraguay. Centramos la mirada en el intercambio de servicios thanatológicos que brindan las vestidoras de difuntos que residen en la Isla Apipé Grande ante el fallecimiento de algún miembro de la comunidad de Ayolas. Estas apreciaciones, que leeremos bajo la idea de thanatología popular, se inscriben en complejos entramados de relaciones consanguíneas o por afinidad que datan de hace más de 50 años y que se mantienen vigentes en las vestidoras que superan las ocho décadas de vida. Para esta presentación se ha seleccionado la intervención de una vestidora de la isla Apipé Grande durante la atención de un caso: el de Ramón el ahorcado Benítez. La información ha sido registrada entre 2006 y 2013, priorizando el método etnográfico, las entrevistas en profundidad, las observaciones y los registros de campo.

Misiones. Una discusión sobre territorio y estado en los espacios fronterizos. En: LaRivada, V. 1, n° 1

El presente trabajo tiene por objeto discutir algunas aproximaciones posibles a los conceptos de territorio, frontera y estado nación, en el marco de una investigación llevada a cabo en la provincia de Misiones, Argentina. Es pertinente mencionar que el territorio de la provincia está rodeado por los estados de Brasil y Paraguay, constituido por límites internacionales. El énfasis está puesto en abordar las relaciones entre frontera-espacio y frontera-territorio en tres localizaciones elegidas para la investigación a) El Soberbio (Ar) - Porto Soberbo – Tiradentes do Sul (Br), b) Bernardo de Irigoyen (Ar) – Barracao (Br) – Dionisio Cerqueira, c) Posadas (Ar) – Encarnación (Py).

7481247Continuidades y discontinuidades en los márgenes. Paso fronterizo Posadas-Encarnación. En LaRivada, V. 1, n° 1

En este trabajo abordaremos la transformación y complejización de las trayectorias de movilidad urbana binacional entre las ciudades de Posadas (Misiones, Argentina) y Encarnación (Itapúa, Paraguay). El habitual sentido del flujo de circulación de personas y bienes sostenido en los últimos 25 años en el paso fronterizo internacional allí existente, presenta transformaciones a partir de 2012, en función de los cambios que las políticas implementadas por los gobiernos centrales de ambos países generan en esta región de frontera. En efecto, no solo se han producido cambios en la movilidad transfronteriza de bienes y servicios, sino además se ha profundizado el patrón de asentamiento metropolitano de ambas ciudades de frontera (Causarano, 2006 e IPEC, 2012). Dicha situación, nos invita a repensar en este trabajo, la noción de integración en acto, es decir, desde la perspectiva de los ciudadanos que comparten esta territorialidad de frontera, poniendo el énfasis en el control del espacio, por parte de los distintos grupos allí presentes.

Las fronteras políticas: “socialismo del siglo XXI” y capitalismo en la profundización del proceso venezolano (Hugo Chávez, 2004-2008). En: LaRivada, V. 1, n° 1

La imposición del socialismo como objeto de debate y orientador de la acción política en Venezuela ha tenido en la discursividad de Chávez un impulso fundamental. En este trabajo, consideramos las estrategias de reformulación intradiscursiva que despliegan cadenas anafóricas a partir de un sintagma –integrado, en general, por “socialismo” u otros lexemas emparentados3- que ocupa el lugar de antecedente. Por otra parte, abordamos la expansión emotiva y el juego axiológico que genera la oposición socialismo / capitalismo. Para introducir ambos tramos nos referimos a la dimensión polémica vinculada con “la radicalización del proceso” y, previamente, justificamos el recorte de los materiales.

Mi vecino Homi Bhabha. En: LaRivada, V. 1, n° 1

En este artículo se indican convergencias y diferencias entre enfoques y conceptos propuestos por Homi Bhabha y mis propias investigaciones. Los ejes temáticos que ordenan este cotejo son los siguientes: 1) Relevancia del lenguaje primario espacial; 2) Umbrales, procesos liminares y contingencia; 3) Configuración del “tercero”, traducciones y procesos paradójicos; 4) Derecho a significar; 5) Vida cotidiana, sentido común y ponderaciones vecinales.