Regulatory and monetary policies meet "too big to fail"

In 2010, the U.S. economy has been showing signs of pulling out of its tailspin. But questions remain about why it took so much monetary policy firepower to deal with the crisis.Global financial crisis ; Monetary policy ; Regulation ; Bank failures ; Financial institutions

Bone quality and mesenchymal stromal cell capacity in total hip replacement: Significance for stem osseointegration measured by radiostereometric analysis

Immediate implant stability is a key factor for success in cementless total hip arthroplasty (THA). Cementless techniques were originally designed for middle-aged patients with normal bone structure and healing capacity, but indications have expanded to also include elderly patients. Poor local bone quality, as a result of osteoporosis (OP), and age-related geometric changes of the proximal femur, may jeopardize initial implant stability and lead to increased migration of the implant components thereby compromising biological fixation and osseointegration. Mesenchymal stromal cells (MSCs) are essential in the process of osseointegration. Age-related dysfunction of MSCs is suggested to be a main contributory factor in altered bone repair with aging and therefore may influence osseointegration. The hypothesis of this prospective clinical study was that preoperative bone quality and MSC capacity dictate stability and osseointegration of femoral stems in cementless THA, especially in women after menopause. A total of 61 consecutive women (age <80 yrs) scheduled for cementless THA for primary hip osteoarthritis (OA) were screened for undiagnosed primary or secondary OP, vitamin D insufficiency and other metabolic bone diseases. Prior to THA, patients underwent aspiration of iliac crest bone marrow for analysis of MSC capacity using optimized isolation and culturing protocols. All patients received a cementless total hip implant with an anatomically designed hydroxyapatite (HA) coated femoral stem and ceramic-ceramic bearings. Per-operative biopsy of the intertrochanteric bone was taken for ex vivo analysis of the local cancellous bone quality using micro-CT imaging and biomechanical testing. After surgery, stem migration and osseointegration was monitored for two years using radiostereometric analysis. The majority of women with hip OA was osteopenic or osteoporotic. These conditions were associated with increased periprosthetic bone loss in the proximal femur and impaired initial stability and delayed osseointegration of the femoral stem. Altered intraosseous dimensions of the proximal femur, as well as aging, also had adverse effects on initial stem stability and were associated with delayed osseointegration. Local bone mineral density of the operated hip and the quality of intertrochanteric cancellous bone had less influence than expected on implant migration. The THA females showed differences in the osteogenic properties of their MSCs. Patients with MSCs of low in vitro osteogenic capacity displayed increased stem subsidence after the initial 3 months settling period and thereby delayed osseointegration. The results suggest that decreased skeletal health, such as low systemic BMD and decreased osteogenic properties of bone marrow MSCs, has major influence on early stability and osseointegration of cementless hip prostheses in female patients.Luun laadun ja mesenkymaalisten kantasolujen toiminnan vaikutus lonkan tekonivelen paranemiseen Tekonivelleikkaus on erinomainen toimenpide lonkan nivelrikon hoidossa. Jos leikkausmenetelmäksi valitaan biologisesti kiinnittyvä tekonivel, olennaisinta on saavuttaa komponenttien välitön stabiliteetti. Se mahdollistaa uudisluun kasvun implantin karhennetulle pinnalle. Ikääntymiseen liittyvä luuston haurastuminen ja reisiluun yläosan ydinontelon laajentuminen voivat heikentää tekonivelen komponenttien tukevuutta ja näin hidastaa niiden kiinnittymistä luuhun. Tällainen on mahdollista erityisesti naisilla vaihdevuosien jälkeen. Näiden potilaiden yksilölliset erot luun parantavien solujen (mesenkymaalisten kantasolujen) määrässä ja toiminnassa voivat osaltaan vaikuttaa heidän tekoniveltensä kiinnittymisnopeuteen. Tähän prospektiiviseen kliiniseen tutkimukseen osallistui 61 naispotilasta, joille tehtiin sementöimätön lonkan tekonivelleikkaus nivelrikon takia. Ennen leikkausta potilaille tehtiin seulontatutkimukset osteoporoosin ja muiden luuston aineenvaihduntasairauksien tunnistamiseksi. Leikkauksen yhteydessä potilailta otettiin luuydinnäyte suoliluusta, josta analysoitiin mesenkymaalisten kantasolujen jakautumis- ja erilaistumiskyky luunsoluiksi. Leikkauksen aikana otettiin näyte reisiluun yläosan hohkaluun hienorakenteen ja mekaanisten ominaisuuksien arvioimiseksi. Leikkauksen jälkeen tekonivelen reisikomponentin kolmiulotteista migraatiota ja kiinnittymistä seurattiin radiostereometrisellä analyysillä (RSA) 2 vuoden ajan. Valtaosalla potilaista oli alentunut luuntiheys (osteopenia tai osteoporoosi). Osteopeenisillä ja osteoporoottisilla potilailla todettiin kiihtynyttä luukatoa tekonivelen reisikomponentin ympärillä sekä komponentin lisääntynyttä migraatiota ja hidastunutta kiinnittymistä. Reisiluun yläosan ydinontelon laajentuminen ja potilaan korkea ikä lisäsivät reisikomponentin migraatiota, mutta reisiluun hohkaluun laatu ei vaikuttanut migraation määrään. Potilailla, joilla todettiin mesenkymaalisten kantasolujen alentunut kyky erilaistua luusoluiksi in vitro, todettiin reisikomponentin lisääntynyttä migraatiota ja hidastunutta kiinnittymistä. Tulokset osoittavat, että ikääntymiseen liittyvät luustomuutokset ja yksilölliset erot mesenkymaalisten kantasolujen määrässä ja toiminnassa voivat osaltaan vaikuttaa lonkan tekonivelten paranemiseen naisilla vaihdevuosien jälkeen.Siirretty Doriast

Constitutional Reform in North Dakota

This thesis attempts to show that the constitution of North Dakota, adopted in 1889, is not capable of serving the needs of modern state government. The debates of the constitutional convention are discussed to show why many of the provisions were incorporated. Proposed constitutional amendments and initiated and referred statutory measures are reviewed to show the type of changes which have been undertaken. The various studies conducted for the purpose of revision are discussed and their recommendations given. The calling of the constitutional convention scheduled for 1972 is also described. Attempts at revising the constitution of North Dakota have met with limited success. Many of the recommendations set forth by the various study groups are sorely needed to bring the structure and methods of government up to date. The study indicates weaknesses in many sections of the constitution. It concludes by recommending changes in the document to bring it up to date

Fed intervention: managing moral hazard in financial crises

At the end of September 2008, U.S. policymakers had been working for more than a year to contain the shock waves from plunging home prices and the subsequent financial market turmoil. For the Federal Reserve, the crisis has given new meaning to the adage that extraordinary times call for extraordinary measures. The central bank has dusted off Depression-era powers and rewritten old rules to address serious risks to the global financial system.Monetary policy - United States ; Financial crises ; Financial markets ; Federal Reserve System

Pairing effects in low density domain of nuclear matter

Using equations, governing np pairing correlations in S=1, T=0 pairing channel (PRC 63 (2001) 021304(R)), it is shown that at low densities equations for the energy gap in the spectrum of quasiparticles and chemical potentials of protons and neutrons allow solutions with negative chemical potential. This corresponds to appearance of Bose--Einstein condensate (BEC) of deuterons in low density region of nuclear matter.Comment: 4 pages, 3 figure

Capillarity-like growth of protein folding nuclei

We analyzed folding routes predicted by a variational model in terms of a generalized formalism of the capillarity scaling theory for 28 two-state proteins. The scaling exponent ranged from 0.2 to 0.45 with an average of 0.33. This average value corresponds to packing of rigid objects.That is, on average the folded core of the nucleus is found to be relatively diffuse. We also studied the growth of the folding nucleus and interface along the folding route in terms of the density or packing fraction. The evolution of the folded core and interface regions can be classified into three patterns of growth depending on how the growth of the folded core is balanced by changes in density of the interface. Finally, we quantified the diffuse versus polarized structure of the critical nucleus through direct calculation of the packing fraction of the folded core and interface regions. Our results support the general picture of describing protein folding as the capillarity-like growth of folding nuclei.Comment: 16 pages,6 figures. Submitted to Proc.Natl.Acad.Sc

Empires and Percolation: Stochastic Merging of Adjacent Regions

We introduce a stochastic model in which adjacent planar regions $A, B$ merge stochastically at some rate $\lambda(A,B)$, and observe analogies with the well-studied topics of mean-field coagulation and of bond percolation. Do infinite regions appear in finite time? We give a simple condition on $\lambda$ for this {\em hegemony} property to hold, and another simple condition for it to not hold, but there is a large gap between these conditions, which includes the case $\lambda(A,B) \equiv 1$. For this case, a non-rigorous analytic argument and simulations suggest hegemony.Comment: 13 page