Receptive fields of single cells of a marsupial visual cortex ofDidelphis virginiana

Zusammenfassung Etwa 40% von 100 Zellen vom visuellen Kortex des BeuteltieresDidelphis virginiana konnten entweder von der rechten oder linken Retina gereizt werden. In der Regel war eine Retina dominant. Areale Summation innerhalb und zwischen den monokulären Feldern war vorhanden, obschon gegenseitige Hemmung innerhalb eines rezeptiven Feldes nicht beobachtet wurde.     

Stress response of leucocytes in hypothyroid rats

Zusammenfassung Nach Formalininjektion zeigen mit getrockneter Schilddrüse gefütterte Ratten eine Abweichung der peripheren Leukocytenreaktion. Bei so behandelten Ratten mit Schilddrüsenhypofunktion ist die Vermehrung der Neutrophilen, die Lymphocytose und die Eosinophilie gehemmt. Auch die histologische Kontrolle ergab eine Hemmung der transitorischen Aktivitätssteigerung des lymphoretikulären Milzgewebes.     

Pliocene eclogite exhumation at plate tectonic rates in eastern Papua New Guinea

As lithospheric plates are subducted, rocks are metamorphosed under high-pressure and ultrahigh-pressure conditions to produce eclogites and eclogite facies metamorphic rocks. Because chemical equilibrium is rarely fully achieved, eclogites may preserve in their distinctive mineral assemblages and textures a record of the pressures, temperatures and deformation the rock was subjected to during subduction and subsequent exhumation. Radioactive parent-daughter isotopic variations within minerals reveal the timing of these events. Here we present in situ zircon U/Pb ion microprobe data that dates the timing of eclogite facies metamorphism in eastern Papua New Guinea at 4.3 +/- 0.4 Myr ago, making this the youngest documented eclogite exposed at the Earth's surface. Eclogite exhumation from depths of approximately 75 km was extremely rapid and occurred at plate tectonic rates (cm yr(-1)). The eclogite was exhumed within a portion of the obliquely convergent Australian-Pacific plate boundary zone, in an extending region located west of the Woodlark basin sea floor spreading centre. Such rapid exhumation (> 1 cm yr(-1)) of high-pressure and, we infer, ultrahigh-pressure rocks is facilitated by extension within transient plate boundary zones associated with rapid oblique plate convergence.