Fence and plough for Lapwings: Nest protection to improve nest and chick survival in Swiss farmland

Switzerland had up to 1000 Lapwing pairs breeding in the 1970s. Actually, there are some 200. The crash was mainly due to a poor productivity of 0.2 to 0.4 fledglings per pair and year. To achieve a fledging rate of at least 0.8 required for population stability, a Recovery Programme was initiated to support a small population of 10-25 pairs breeding in central Switzerland. In 2004 to 2006 all nests were marked and spared during field labour by the farmers. As a result of a well established cooperation with the local farmers, not a single nest was destroyed by agricultural activities. However, there was a high risk of nest desertion when farming activities took place during the period of egg laying. Therefore, it might be worth to postpone field labour for some days to allow clutch completion. In 2005 and 2006, but not in 2004, most nests were protected from ground predators by surrounding entire fields rather than individual clutches with electro-fences as used in sheep farming. While 95 % of clutches within the fences hatched successfully, 61 % of unprotected nests were predated. In 2006 the influence of predation on chick survival was investigated by radio-tagging 81 chicks soon after hatching. They had no difficulties to cross the electro-fences. Predation occurred mostly at night (73 %) and outside the fences (87 %). Of 46 chicks predated at night only one was taken inside an electro-fence. Daytime predation played a minor role (27 % of all chick predations) and occurred at the same rate inside and outside the electro-fence. Reproductive success in 2005 was an estimated 0.8 fledging young per pair and year. In 2006, however, it dropped to 0.25 due to heavy chick predation.In den 1970er Jahren umfasste der Brutbestand des Kiebitzes in der Schweiz ca. 1000 Paare. Heute sind es schätzungsweise nur noch ca. 200. Für diesen dramatischen Rückgang dürfte in erster Linie der viel zu geringe Reproduktionserfolg verantwortlich sein (0.2-0.4 flügge Junge pro Brutpaar und Jahr). Um den Bruterfolg auf ein populationserhaltendes Mass von ca. 0.8 Jungen pro Paar zu steigern, wurde bei einem Restbestand in der Zentralschweiz (10-25 Paare) ein Artenförderungsprogramm in Angriff genommen. In den Jahren 2004-2006 wurden alle Kiebitzgelege markiert und auf diese Weise von der Feldbearbeitung ausgespart. Dank der ausgezeichneten Zusammenarbeit mit den örtlichen Landwirten ging in dieser Zeit kein Kiebitzgelege bei landwirtschaftlichen Feldarbeiten verloren. Wenn allerdings die Bodenbearbeitung während der Gelegeproduktion erfolgte, wurden verhältnismässig viele Bruten aufgegeben. Hier kann es ratsam sein, die landwirtschaftliche Bearbeitung hinauszuzögern bis die Vögel mit dem Bebrüten des Vollgeleges begonnen haben. 2005 und 2006, nicht aber 2004, wurden Kiebitzgelege zusätzlich mit einem Elektrozaun, wie er bei Schafhaltern üblich ist, gegen Raubsäuger gesichert. Eingezäunt wurden in der Regel ganze Felder. In den so gesicherten Kulturen schlüpften 95 % der Gelege, in den nicht eingezäunten nur 39 %. 2006 wurden 81 Kiebitzküken besendert, um deren Überlebensraten und den Einfluss der Prädation zu untersuchen. Die Küken konnten den Elektrozaun ohne weiteres passieren (bodennahe Maschen 10x15 cm). Kükenverluste durch Prädation ereigneten sich überwiegend nachts (73 % aller Verluste) und außerhalb der Elektrozäune (87 % aller Verluste). Von 46 in der Nacht prädierten Küken stammte nur eines aus einer Elektro-Umzäunung. Kükenverluste, die durch tagaktive Prädatoren verursacht wurden, spielten eine untergeordnete Rolle (27 % aller Verluste). Sie traten innerhalb und außerhalb der Elektroumzäunungen in gleichem Umfang auf. Der Bruterfolg des Kiebitzes lag in 2005 bei einem bestandserhaltenden Wert von 0.8 Küken pro Paar. In 2006 führten hohe, prädationsbedingte Kükenverluste zu einem Bruterfolg von lediglich 0.25 Küken pro Paar

Erratum

Response to alpha 2B interferon treatment in a haemodialysis patient with chronic hepatitis C. The complete list of authors contributing to the above letter should have appeared as follows: G. Barril, J. A. Schez Tomero, L. Garcia Buey, J. L. Motellon, C. Bernis and J. A. Trave

Interfacing Nanoparticles to Biological Systems

Nature has created biomolecular machines that function with remarkable efficiency and precision. In recent years, science has attained an unprecedented understanding of the mechanisms of biological “machines.” This has inspired utilization of Nature’s engineering for applications in computation, self-assembly, and mechanics. Because biomolecules are inherently on the nanoscale, nanotechnology has emerged as an appropriate means for controlling biology. This requires both understanding the inorganic properties of the nanoparticle as well as creating an interface that is compatible with the complex and highly disordered environments of real biological systems. We will discuss the use of nanoparticles composed of Au, Fe3O4, Fe2O3, CoFe2O4, and similar materials in biological applications by engineering both the inorganic properties of the nanoparticles along with creating optimal biological interfaces. We study the interface between the nanoparticle and covalently linked proteins and DNA. Labeling proteins with nanoparticles has been utilized for many applications but often the structure of the protein in the conjugate is not characterized. In addition, site-specific labeling of the protein with a nanoparticle has been achieved for only a limited set of proteins and nanoparticles. We present work in which we study the interface between nanoparticles and the protein cytochrome c. We vary nanoparticle ligand and composition, as well as labeling site on the protein. Biophysical techniques such as quantitative gel electrophoresis, circular dichroism, and optical spectroscopy are used to characterize the structure of the protein in the conjugate. These experiments allow us to understand some of the chemical interactions involved in non-specific adsorption, and come up with general design rules for optimal conjugation

Ectosomes as immunomodulators

Considerable progress has been made in recognizing microvesicles as important mediators of intercellular communication rather than irrelevant cell debris. Microvesicles released by budding directly from the cell membrane surface (i.e., ectocytosis) either spontaneously or in response to various stimuli are called shed vesicles or ectosomes. Ectosomes are rightside-out vesicles with cytosolic content, and they expose phosphatidylserine in the outer leaflet of their membrane. Depending on their cellular origin, ectosomes have been associated with a broad spectrum of biological activities. In the light of recent findings, we now know that ectosomes derived from polymorphonuclear leukocytes, erythrocytes, platelets, and tumor cells have profound effects on the innate immune system, as well as on the induction of the adaptive immunity, globally reprogramming cells such as macrophages or dendritic cells toward an immunosuppressive and possibly tolerogenic phenotype. Although the effects observed in the circulation are mainly procoagulant and pro-inflammatory, ectosomes might be anti-inflammatory/immunosuppressive in local inflammatio

Release mechanism of octadecyl rhodamine B chloride from Au nanorods by ultrafast laser pulses

We investigated the release of octadecyl rhodamine B chloride (R[subscript 18]) loaded onto cetyltrimethylammonium bromide (CTAB) coated gold nanorods (NR) by pulsed ultrafast laser excitation. R[subscript 18] intercalates into the hydrophobic CTAB bilayer on the NR surface and can exchange on and off the NR with free CTAB micelles in solution. We find that laser excitation accelerates the rate of both R[subscript 18] release from the NR and R[subscript 18] binding to the NR with increasing fluence. However, at laser fluences >220 μJ/cm[superscript 2] thermal degradation of the R[subscript 18] dominates. We also find that the concentration of CTAB, particularly around the critical micelle concentration, strongly influences the release and binding rates