A polymorphism causing deficiencies in Toll-interacting protein (TOLLIP), an inhibitory adaptor protein affecting endosomal trafficking, is associated with increased tuberculosis (TB) risk. It is, ...however, unclear how TOLLIP affects TB pathogenesis. Here we show that TB severity is increased in Tollip
mice, characterized by macrophage- and T cell-driven inflammation, foam cell formation and lipid accumulation. Tollip
alveolar macrophages (AM) specifically accumulated lipid and underwent necrosis. Transcriptional and protein analyses of Mycobacterium tuberculosis (Mtb)-infected, Tollip
AM revealed increased EIF2 signalling and downstream upregulation of the integrated stress response (ISR). These phenotypes were linked, as incubation of the Mtb lipid mycolic acid with Mtb-infected Tollip
AM activated the ISR and increased Mtb replication. Correspondingly, the ISR inhibitor, ISRIB, reduced Mtb numbers in AM and improved Mtb control, overcoming the inflammatory phenotype. In conclusion, targeting the ISR offers a promising target for host-directed anti-TB therapy towards improved Mtb control and reduced immunopathology.
For about a month near the boreal vernal equinox, the eastern Pacific intertropical convergence zone (ITCZ) is observed to form two troughs quasi-symmetrically situated about the equator near 5°–7° ...latitude during years when an equatorial sea surface cold tongue is present (e.g., La Niña years). The three-dimensional structure and temporal evolution of the eastern Pacific double ITCZ is documented using weekly cloud liquid and ice water fields and relative humidity profiles retrieved from Special Sensor Microwave/Temperature-2 measurements. The depth of convection in the southern branch of the double ITCZ, as determined by the coincident presence of cloud liquid and ice as well as by upward motion inferred from the relative humidity field, is observed to be sensitive to both the underlying SST and subsidence from the northern branch. The equatorial sea surface cold tongue appears to be the determining factor regulating the formation of a double ITCZ in the eastern Pacific. Areas of deep convection within the double ITCZ are accompanied by surface wind convergence maxima. However, the coincident maxima in deep convection and surface convergence are located several degrees of latitude equatorward of the highest sea surface temperatures.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The radiation damage resulting from the large particle fluences predicted at the Superconducting Super Collider induces significant leakage currents in Si detectors. In order to limit these currents, ...the detectors are operated at reduced temperatures ( approximately 0 degrees C). Results are presented of a study of temperature effects on both the initial radiation damage and the long-term annealing of that damage in Si PIN detectors. Depletion voltage results are reported. The detectors are exposed to approximately 10/sup 14//cm/sup 2/ 650-MeV protons. Very pronounced temperature dependences are observed.< >
As part of a program to develop a silicon strip central tracking detector system for the Superconducting Super Collider (SSC), the effects of radiation damage in silicon detectors and their ...associated front-end readout electronics are being studied. The authors report on the results of neutron and proton irradiations at the Los Alamos National Laboratory and gamma -ray irradiations at UC Santa Cruz. Individual components on single-sided AC-coupled silicon strip detectors and on test structures were tested. Circuits fabricated in a radiation-hard CMOS process and individual transistors fabricated using dielectric isolation bipolar technology were also studied. Bulk damage to the silicon itself is seen as the limiting factor in the lifetime of a detector system. In particular, it is the acceptor site creation in the active volume of the silicon detector that will limit the lifetime to approximately 10 yr for the innermost detectors.< >
The VME-based D0 muon trigger electronics Fortner, M.; Green, J.; Hedin, D. ...
IEEE transactions on nuclear science,
04/1991, Letnik:
38, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The trigger electronics for the muon system of the Fermilab D0 detector is described. The hardware trigger consists of VME-based cards designed to find probable tracks in individual chambers and then ...match these track segments. The fast trigger is highly parallel and able to discern probable tracks from about 15000 trigger cells in under 200 ns from receipt of all bits in the counting house. There is a parallel confirmation trigger with a response time of 1-5 mu s that provides a crude calculation of the momentum and charge of the muon.< >
The three-dimensional structure of pectate lyase E (PeIE) has been determined by crystallographic techniques at a resolution of 2.2 angstrom. The model includes all 355 amino acids but no solvent, ...and refines to a crystallographic refinement factor of 20.6%. The polypeptide backbone folds into a large right-handed cylinder, termed a parallel beta helix. Loops of various sizes and conformations protrude from the central helix and probably confer function. A putative Ca2+-binding site as well as two cationic sites have been deduced from the location of heavy atom derivatives. Comparison of the PelE and recently determined pectate lyase C (PelC) structures has led to identification of a putative polygalacturonate-binding region in PelE. Structural differences relevant to differences in the enzymatic mechanism and maceration properties of PelE and PelC have been identified. The comparative analysis also reveals a large degree of structural conservation of surface loops in one region as well as an apparent aromatic specificity pocket in the amino-terminal branch. Also discussed is the sequence and possible functional relationship of the pectate lyases with pollen and style plant proteins
Silicon detectors at future collider facilities such as the Superconducting Super Collider (SSC) will be exposed to large fluences of both neutral and charged particles, resulting in considerable ...bulk radiation damage. In order to reduce the increase in leakage current associated with that damage, the proposed operating temperature of the silicon detectors in the SSC Solenoidal Detector Collaboration (SDC) experiment is 0 degrees C. In order to explore any potential complications of operating detectors at 0 degrees C, two sets of detectors were irradiated. One set was kept close to 0 degrees C during the exposure and annealing period, while the other was maintained at room temperature throughout ( approximately 27 degrees C during the exposure, and approximately 23 degrees C during the annealing period). The full depletion voltage and leakage current of the detectors during the irradiation period and over the subsequent annealing period were monitored. It is concluded that detectors will have to be operated at 0 degrees C, and, once damaged, be maintained at 0 degrees C in order to keep their operating voltage at a reasonable value (<<160 V). Turning off the bias voltage when the detectors are not in use seems to provide an extra margin of safety.< >
Summary form only given, as follows. As part of a program to develop silicon central tracking systems for the next generation of high-energy, high-luminosity accelerators such as the Superconducting ...Super Collider and the Relativistic Heavy Ion Collider, the effects of radiation damage in silicon detectors are being studied in detail. Results on neutron and proton irradiations at Los Alamos National Laboratory and gamma ray irradiations at UC Santa Cruz have been obtained. The devices being tested include both single-sided and double-sided silicon strip detectors, as well as test structures. Results of measurements of leakage current, acceptor state creation, charge trapping, pulse shapes, and changes in interstrip resistance as a function dose and operating temperature have been obtained.< >
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