1,039 research outputs found
Boundary regularity of conformally compact Einstein metrics
We show that C^2 conformally compact Riemannian Einstein metrics have
conformal compactifications that are smooth up to the boundary in dimension 3
and all even dimensions, and polyhomogeneous in odd dimensions greater than 3.Comment: Latex2e, 25 pages. This is the final version accepted for publication
in the Journal of Differential Geometr
Global carbon mechanisms: emerging lessons and implications
The global carbon mechanisms have succeeded in channelling billions of Euros towards low-carbon investments in developing countries, but cannot deliver what is needed in the future without support including reforms and involvement of North America. The publication shows that the Clean Development Mechanism itself has triggered more than 4000 emission-reducing projects in developing countries and is likely to save up to 2 billion tonnes of emissions reductions by 2012. Other Mechanisms under the Kyoto Protocol, including emerging Green Investment Schemes, show great promise. But many of the gains are at peril, warns the publication, unless governments act to restore balance in the markets and learn the emerging lessons. The publication identifies and analyses three fundamental problems that must be tackled. An excess of supply over demand will mean low prices in the market without government action There must be reforms to improve the efficiency and environmental performance of the existing mechanisms The Global Carbon Mechanisms are and will continue to be a central pillar in the global response to climate change to 2020, but are not on their own sufficient. They need to be complemented by other action to support the required cuts in carbon emission
Understanding the dynamics of biological colloids to elucidate cataract formation towards the development of methodology for its early diagnosis
The eye lens is the most characteristic example of mammalian tissues
exhibiting complex colloidal behaviour. In this paper we briefly describe how
dynamics in colloidal suspensions can help addressing selected aspects of lens
cataract which is ultimately related to the protein self-assembly under
pathological conditions. Results from dynamic light scattering of eye lens
homogenates over a wide protein concentration were analyzed and the various
relaxation modes were identified in terms of collective and self-diffusion
processes. Using this information as an input, the complex relaxation pattern
of the intact lens nucleus was rationalized. The model of cold cataract - a
phase separation effect of the lens cytoplasm with cooling - was used to
simulate lens cataract at in vitro conditions in an effort to determine the
parameters of the correlation functions that can be used as reliable indicators
of the cataract onset. The applicability of dynamic light scattering as a
non-invasive, early-diagnostic tool for ocular diseases is also demonstrated in
the light of the findings of the present paper.Comment: Slightly different version from the published one 10 pages, 2 figure
Nuclear localization of the mitochondrial factor HIGD1A during metabolic stress.
Cellular stress responses are frequently governed by the subcellular localization of critical effector proteins. Apoptosis-inducing Factor (AIF) or Glyceraldehyde 3-Phosphate Dehydrogenase (GAPDH), for example, can translocate from mitochondria to the nucleus, where they modulate apoptotic death pathways. Hypoxia-inducible gene domain 1A (HIGD1A) is a mitochondrial protein regulated by Hypoxia-inducible Factor-1α (HIF1α). Here we show that while HIGD1A resides in mitochondria during physiological hypoxia, severe metabolic stress, such as glucose starvation coupled with hypoxia, in addition to DNA damage induced by etoposide, triggers its nuclear accumulation. We show that nuclear localization of HIGD1A overlaps with that of AIF, and is dependent on the presence of BAX and BAK. Furthermore, we show that AIF and HIGD1A physically interact. Additionally, we demonstrate that nuclear HIGD1A is a potential marker of metabolic stress in vivo, frequently observed in diverse pathological states such as myocardial infarction, hypoxic-ischemic encephalopathy (HIE), and different types of cancer. In summary, we demonstrate a novel nuclear localization of HIGD1A that is commonly observed in human disease processes in vivo
Enthalpy and the Mechanics of AdS Black Holes
We present geometric derivations of the Smarr formula for static AdS black
holes and an expanded first law that includes variations in the cosmological
constant. These two results are further related by a scaling argument based on
Euler's theorem. The key new ingredient in the constructions is a two-form
potential for the static Killing field. Surface integrals of the Killing
potential determine the coefficient of the variation of the cosmological
constant in the first law. This coefficient is proportional to a finite,
effective volume for the region outside the AdS black hole horizon, which can
also be interpreted as minus the volume excluded from a spatial slice by the
black hole horizon. This effective volume also contributes to the Smarr
formula. Since the cosmological constant is naturally thought of as a pressure,
the new term in the first law has the form of effective volume times change in
pressure that arises in the variation of the enthalpy in classical
thermodynamics. This and related arguments suggest that the mass of an AdS
black hole should be interpreted as the enthalpy of the spacetime.Comment: 21 pages; v2 references adde
First inappropriate implantable cardioverter defibrillator therapy is often due to inaccurate device programming: analysis of the French OPERA registry
AIMS:Inappropriate therapy delivered by implantable cardioverter defibrillators (ICDs) remains a challenge. The OPERA registry measured the times to, and studied the determinants of, first appropriate (FAT) and inappropriate (FIT) therapies delivered by single-, dual- and triple-chamber [cardiac resynchronization therapy defibrillator (CRT-D)] ICD. METHODS AND RESULTS: We entered 636 patients (mean age = 62.0 ± 13.5 years; 88% men) in the registry, of whom 251 received single-, 238 dual-, and 147 triple-chamber ICD, for primary (30.5%) or secondary (69.5%) indications. We measured times to FAT and FIT as a function of multiple clinical characteristics, examined the effects of various algorithm components on the likelihood of FAT and FIT delivery, and searched for predictors of FAT and FIT. Over 22.8 ± 8.8 months of observation, 184 patients (28.9%) received FAT and 70 (11.0%) received FIT. Ventricular tachycardia (VT) was the trigger of 88% of FAT, and supraventricular tachycardia was the trigger of 91% of FIT. The median times to FIT (90 days; range 49-258) and FAT (171 days; 50-363) were similar. The rate of FAT was higher (P <0.001) in patients treated for secondary than primary indications, while that of FIT were similar in both groups. Out of 57 analysable FIT, 27 (47.4%) could have been prevented by fine tuning the device programming like the sustained rate duration or the VT discrimination algorithm. CONCLUSIONS: First inappropriate therapy occurred in 11% of 636 ICD recipients followed for ∼2 years. Nearly 50% of FIT could have been prevented by improving device programming
On the uniqueness and global dynamics of AdS spacetimes
We study global aspects of complete, non-singular asymptotically locally AdS
spacetimes solving the vacuum Einstein equations whose conformal infinity is an
arbitrary globally stationary spacetime. It is proved that any such solution
which is asymptotically stationary to the past and future is itself globally
stationary.
This gives certain rigidity or uniqueness results for exact AdS and related
spacetimes.Comment: 18pp, significant revision of v
21 sguardi sulla costruzione ecologica in europa
21 interviste a professionisti edili nel campo della progettazione, realizzazione e assicurazione sono state elaborate nel 2011 nel quadro del progetto europeo INATER' sulla costruzione ecologica
Tutti questi professionisti hanno fatto la scelta di utilizzare materiali naturali o riciclati, sia per interventi di nuova costruzioni che nel campo del recupero e restauro.
Interessati a isolare in maniera efficace le costruzioni, sono altresì interessati a garantire il comfort degli operatori e dei fruitori, lo sviluppo delle filiere corte o la diminuzione degli impatti ambientali. Tutti apportano innovazione, contribuendo ognuno secondo le proprie possibilità, ad un'evoluzione del mondo della costruzione
Il collettivo INATER' vi offre queste testimonianze raccolte in una Guida che illustra al contempo alcune informazioni tematiche sui seguenti temi: lo sviluppo del mercato, la problematica delle assicurazioni, il quadro normativo....
La Guida è al servizio di tutti gli attori del mondo edile che lavorano sul cantiere, in studi di progettazione, in un raggruppamento d'imprese o in centri di formazion
Neurophysiological effects of human-derived pathological tau conformers in the APPKM670/671NL.PS1/L166P amyloid mouse model of Alzheimer's disease
Alzheimer's Disease (AD) is a neurodegenerative disease characterized by two main pathological hallmarks: amyloid plaques and intracellular tau neurofibrillary tangles. However, a majority of studies focus on the individual pathologies and seldom on the interaction between the two pathologies. Herein, we present the longitudinal neuropathological and neurophysiological effects of a combined amyloid-tau model by hippocampal seeding of human-derived tau pathology in the APP.PS1/L166P amyloid animal model. We statistically assessed both neurophysiological and pathological changes using linear mixed modelling to determine if factors such as the age at which animals were seeded, genotype, seeding or buffer, brain region where pathology was quantified, and time-post injection differentially affect these outcomes. We report that AT8-positive tau pathology progressively develops and is facilitated by the amount of amyloid pathology present at the time of injection. The amount of AT8-positive tau pathology was influenced by the interaction of age at which the animal was injected, genotype, and time after injection. Baseline pathology-related power spectra and Higuchi Fractal Dimension (HFD) score alterations were noted in APP.PS1/L166P before any manipulations were performed, indicating a baseline difference associated with genotype. We also report immediate localized hippocampal dysfunction in the electroencephalography (EEG) power spectra associated with tau seeding which returned to comparable levels at 1 month-post-injection. Longitudinal effects of seeding indicated that tau-seeded wild-type mice showed an increase in gamma power earlier than buffer control comparisons which was influenced by the age at which the animal was injected. A reduction of hippocampal broadband power spectra was noted in tau-seeded wild-type mice, but absent in APP.PS1 animals. HFD scores appeared to detect subtle effects associated with tau seeding in APP.PS1 animals, which was differentially influenced by genotype. Notably, while tau histopathological changes were present, a lack of overt longitudinal electrophysiological alterations was noted, particularly in APP.PS1 animals that feature both pathologies after seeding, reiterating and underscoring the difficulty and complexity associated with elucidating physiologically relevant and translatable biomarkers of Alzheimer's Disease at the early stages of the disease
Gefäßchirurgische Ausbildung in endovaskulärer Technik in Lausanne
Zusammenfassung: Zwischen 1995 und 2005 wuchs die Anzahl der jährlich von uns mit endovaskulären Techniken versorgten Aortenaneurysmen (EVAR) von 0 auf 50, und dies auf allen Stufen der Aorta. Zu unserer Organisation gehören ein breites Team von Chirurgen, ein Lager mit 3kompletten Familien von Endoprothesen (gerade Endoprothesen, konische Endoprothesen, und Bifurkationen), ein mobiler Wagen mit Zubehör (Einführungsbestecke, Führungsdrähte, Katheter, Ballone etc.) und ein Apparat auf Rädern für die intravaskuläre Ultraschalluntersuchung (IVUS). Letzterer erlaubt es zusammen mit einer mobilen Durchleuchtungsanlage (C-Bogen), in jedem Operationssaal unserer Institution endovaskulär Aneurysmen zu analysieren, und dies in der Regel ohne Angiographie bzw. Kontrastmittel. Deshalb sind wir nicht mehr auf eine ausgiebige bildgebende präoperative Abklärung potenzieller Kandidaten für eine endovaskuläre Sanierung von Aneurysmen angewiesen und können rupturierte Aneurysmen der Bauchaorta oder der thorakalen Aorta ohne Verzug behandeln. Bei der endovaskulären Sanierung von Aortenaneurysmen unterscheiden wir zwischen Prozessschritten (Indikationsstellung, Darstellung der Zugangsgefäße, Ausmessen mittels IVUS und Roadmapping mittels Durchleuchtung, Implantatwahl, Implantatinsertion, Positionierung, Implantatabwurf, Erfolgsbeurteilung, Rekonstruktion der Zugangsgefäße und Nachkontrolle) und Kompetenzstufen (Assistent, Oberarzt, Leitender Arzt). Unsere ultraschallgestützte Technik zur endovaskulären Sanierung von Aneurysmen wurde mittels IVUS-Transporter und Telementoring erfolgreich auch anderen Institutionen zur Verfügung gestell
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