660 research outputs found
Three papers from conference on "Wing and tail-surface oscillations : March 6-8, 1941, Munich
Discrimination of different volcanic rock units by magnetic properties — geothermal field at Reykjanes peninsula (SW-Iceland)
The geothermal field at Reykjanes
peninsula is located at the boundary
where the submarine Reykjanes Ridge
passes over into the rift zone of southwestern
Iceland. The geothermal field
coincides with a magnetic low in the
aeromagnetic anomaly map and is situated
within a dense NE–SW fissure and
fault zone. Surface geology is characterized
by different historic fissure eruptions
(youngest from 1226AD), shield
lava (12.5–14.5 ka) and intercalated pillow
basalt–hyaloclastite ridges probably
formed during the last glacial episode
(14.5–20 ka). During a field magnetic
study in the vicinity of the geothermal
field in summer 2005 different
volcanic rock units have been sampled
to correlate rock magnetic and
magneto-mineralogical properties with
magnetic field intensity. Additionally,
measurements on a dense dolerite intrusion,
recovered from the RN–19 borehole
(2245–2248m depth) in May 2005
within the frame of IDDP, should shed
light on the influence of crustal rocks on
the total magnetic field intensity.
Generally, the natural remanent magnetization
and magnetic susceptibility,
measured on rock specimen, is high,
ranging between 2.5 and 33.6Am−1
and 2–37 ×10−3 SI, respectively...conferenc
Atmospheric deposition of nutrients and excess N formation in the North Atlantic
Anthropogenic emissions of nitrogen (N) to the atmosphere have been strongly increasing during the last century, leading to greater atmospheric N deposition to the oceans. The North Atlantic subtropical gyre (NASTG) is particularly impacted. Here, upwind sources of anthropogenic N from North American and European sources have raised atmospheric N deposition to rates comparable with N2 fixation in the gyre. However, the biogeochemical fate of the deposited N is unclear because there is no detectable accumulation in the surface waters. Most likely, deposited N accumulates in the main thermocline instead, where there is a globally unique pool of N in excess of the canonical Redfield ratio of 16 N:1 phosphorus (P). To investigate this depth zone as a sink for atmospheric N, we used a biogeochemical ocean transport model and year 2000 nutrient deposition data. We examined the maximum effects of three mechanisms that may transport excess N from the ocean surface to the main thermocline: physical transport, preferential P remineralization of sinking particles, and nutrient uptake and export by phytoplankton at higher than Redfield N:P ratios. Our results indicate that atmospheric deposition may contribute 13-19% of the annual excess N input to the main thermocline. Modeled nutrient distributions in the NASTG were comparable to observations only when non-Redfield dynamics were invoked. Preferential P remineralization could not produce realistic results on its own; if it is an important contributor to ocean biogeochemistry, it must co-occur with N2 fixation. The results suggest that: 1) the main thermocline is an important sink for anthropogenic N deposition, 2) non-Redfield surface dynamics determine the biogeochemical fate of atmospherically deposited nutrients, and 3) atmospheric N accumulation in the main thermocline has long term impacts on surface ocean biology
The morphological and clinical relevance of mandibular and maxillary bone structures for implantation
Tooth loss, which interrupts the biocybernetic feedback circuit of the masticatory
system, changes the structures of the jaw bone: such changes are termed
"inactivity atrophy". The mandible is subject to vertical atrophy and the maxilla is
primarily subject to horizontal atrophy. The mandible possesses more compact
bone, the maxilla more spongy; the resorption directions also differ (mandible:
towards the oral aspect; maxilla: towards the vestibular). An implant helps to
restore the biocybernetic feedback system. The amount of available bone, bone
structure, and topographic conditions are crucial factors influencing implant
success. Osseointegration is performed at an early stage (which includes bleeding,
granulation tissue, foreign-body recognition, interactions) and at a late stage
(so-called osseous bridging, development of fibrous and lamellar bone)
Results for the response function determination of the Compact Neutron Spectrometer
The Compact Neutron Spectrometer (CNS) is a Joint European Torus (JET)
Enhancement Project, designed for fusion diagnostics in different plasma
scenarios. The CNS is based on a liquid scintillator (BC501A) which allows good
discrimination between neutron and gamma radiation. Neutron spectrometry with a
BC501A spectrometer requires the use of a reliable, fully characterized
detector. The determination of the response matrix was carried out at the Ion
Accelerator Facility (PIAF) of the Physikalisch-Technische Bundesanstalt (PTB).
This facility provides several monoenergetic beams (2.5, 8, 10, 12 and 14 MeV)
and a 'white field'(Emax ~17 MeV), which allows for a full characterization of
the spectrometer in the region of interest (from ~1.5 MeV to ~17 MeV. The
energy of the incoming neutrons was determined by the time of flight method
(TOF), with time resolution in the order of 1 ns. To check the response matrix,
the measured pulse height spectra were unfolded with the code MAXED and the
resulting energy distributions were compared with those obtained from TOF. The
CNS project required modification of the PTB BC501A spectrometer design, to
replace an analog data acquisition system (NIM modules) with a digital system
developed by the 'Ente per le Nuove tecnologie, l'Energia e l'Ambiente' (ENEA).
Results for the new digital system were evaluated using new software developed
specifically for this project.Comment: Proceedings of FNDA 201
Biochemistry and functional aspects of human glandular kallikreins
Human urinary kallikrein was purified by gel filtration on Sephacryl S-200 and affinity chromatography on aprotinin-Sepharose, followed by ion exchange chromatography on DEAE-Sepharose. In dodecylsulfate gel electrophoresis two protein bands with molecular weights of 41,000 and 34,000 were separated. The amino acid composition and the carbohydrate content of the kallikrein preparation were determined; isoleucine was identified as the only aminoterminal amino acid. The bimolecular velocity constant for the inhibition by diisopropyl fluorophosphate was determined as 9±2 l mol–1 min–1. The hydrolysis of a number of substrates was investigated and AcPheArgOEt was found to be the most sensitive substrate for human urinary kallikrein. Using this substrate an assay method for kallikrein in human urine was developed.
It was shown by radioimmunoassay that pig pancreatic kallikrein can be absorbed in the rat intestinal tract. Furthermore, in dogs the renal excretion of glandular kallikrein from blood was demonstrated by radioimmunological methods
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Social Mpower: An Educational Game for Energy Efficiency
A number of serious games have been developed for energy systems that act as an educational tool and help energy consumers to better understand concepts such as resource allocation, electricity prices and grid sustainability. In such gamified environments, players use technology to solve environmental problems including greener environment, optimised energy and water infrastructure, sustainable resources and reduced energy use. Social Mpower game is a representation of an autonomous energy community for local power generation and distribution in which the participants have to avoid a collective blackout by individually reducing their energy consumption by synchronising and coordinating their actions. Our experimental hypothesis is that collective awareness can be enhanced by appropriate features of the game interface, and therefore to increase the opportunities and prospects for successful collective action (e.g to avoid a blackout)
Circulating Senescent T Cells Are Linked to Systemic Inflammation and Lesion Size During Human Cutaneous Leishmaniasis
Leishmania (Viannia) braziliensis induces American tegumentary leishmaniasis that
ranges in severity from the milder form, cutaneous (CL) to severe disseminated
cutaneous leishmaniasis. Patients with CL develop a cell-mediated Th1 immune
response accompanied by production of inflammatory cytokines, which contribute to
parasite control and pathogenesis of disease. Here, we describe the accumulation of
circulating T cells with multiple features of telomere dependent-senescence including
elevated expression of CD57, KLRG-1, and γH2AX that have short telomeres and low
hTERT expression during cutaneous L. braziliensis infection. This expanded population
of T cells was found within the CD45RA+CD27− (EMRA) subset and produced high
levels of inflammatory cytokines, analogous to the senescence-associated secretory
profile (SASP) that has been described in senescent non-lymphoid cells. There was
a significant correlation between the accumulation of these cells and the extent of
systemic inflammation, suggesting that they are involved in the inflammatory response
in this disease. Furthermore, these cells expressed high level of the skin homing
receptor CLA and there was a highly significant correlation between the number of
these cells in the circulation and the size of the Leishmania-induced lesions in the
skin. Collectively our results suggest that extensive activation during the early stages
of leishmaniasis drives the senescence of T cells with the propensity to home to the skin.
The senescence-related inflammatory cytokine secretion by these cells may control the
infection but also contribute to the immunopathology in the disease
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