Comparative models disentangle drivers of fruit production variability of an economically and ecologically important long-lived Amazonian tree.

Trees in the upper canopy contribute disproportionately to forest ecosystem productivity. The large, canopy-emergent Bertholletia excelsa also supports a multimillion-dollar commodity crop (Brazil nut), harvested almost exclusively from Amazonian forests. B.

Influence of the amount of intermetallics on the degradation of Mg-Nd alloys under physiological conditions.

The influence of amount of intermetallics on the degradation of as-extruded Mg-Nd alloys with different contents of Nd was investigated via immersion testing in DMEM+10% FBS under cell culture conditions and subsequent microstructural characterizations. It is found that the presence of intermetallic particles MgNd affects the corrosion of Mg-Nd alloys in two conflicting ways. One is their negative role that their existence enhances the micro-galvanic corrosion.

How We Got Smart: Improving Interdisciplinary Communication When Summoning Neonatology to High-Risk Deliveries.

Communication around high-risk deliveries is critical to ensure patient safety. A hospital-wide system change in paging the neonatal resuscitation team (NRT) to deliveries was implemented but disliked. An interdisciplinary team seized the opportunity to explore opportunities for an enhanced system to improve communication.

Influence of Dy in solid solution on the degradation behavior of binary Mg-Dy alloys in cell culture medium.

Rare earth element Dy is one of the promising alloying elements for magnesium alloy as biodegradable implants. To understand the effect of Dy in solid solution on the degradation of Mg-Dy alloys in simulated physiological conditions, the present work studied the microstructure and degradation behavior of Mg-Dy alloys in cell culture medium. It is found the corrosion resistance enhances with the increase of Dy content in solid solution in Mg.

Antibacterial biodegradable Mg-Ag alloys.

The use of magnesium alloys as degradable metals for biomedical applications is a topic of ongoing research and the demand for multifunctional materials is increasing. Hence, binary Mg-Ag alloys were designed as implant materials to combine the favourable properties of magnesium with the well-known antibacterial property of silver. In this study, three Mg-Ag alloys, Mg2Ag, Mg4Ag and Mg6Ag that contain 1.

Microstructure, mechanical and corrosion properties of Mg-Dy-Gd-Zr alloys for medical applications.

In previous investigations, a Mg-10Dy (wt.%) alloy with a good combination of corrosion resistance and cytocompatibility showed great potential for use as a biodegradable implant material. However, the mechanical properties of Mg-10Dy alloy are not satisfactory.

Tradeoffs in basal area growth and reproduction shift over the lifetime of a long-lived tropical species.

Understanding of the extent to which reproductive costs drive growth largely derives from reproductively mature temperate trees in masting and non-masting years. We modeled basal area increment (BAI) and explored current growth-reproduction tradeoffs and changes in such allocation over the life span of a long-lived, non-masting tropical tree. We integrated rainfall and soil variables with data from 190 Bertholletia excelsa trees of different diameter at breast height (DBH) sizes, crown characteristics, and liana loads, quantifying BAI and reproductive output over 4 and 6 years, respectively.

Pollen and seed flow patterns of Carapa guianensis Aublet. (Meliaceae) in two types of Amazonian forest.

Various factors affect spatial genetic structure in plant populations, including adult density and primary and secondary seed dispersal mechanisms. We evaluated pollen and seed dispersal distances and spatial genetic structure of Carapa guianensis Aublet. (Meliaceae) in occasionally inundated and terra firme forest environments that differed in tree densities and secondary seed dispersal agents.

Element distribution in the corrosion layer and cytotoxicity of alloy Mg-10Dy during in vitro biodegradation.

The present work investigates the corrosion behaviour, the element distribution in the corrosion layer and the cytocompatibility of alloy Mg-10Dy. The corrosion experiments were performed in a cell culture medium (CCM) under cell culture conditions close to the in vivo environment. The element distribution on the surface as well as in cross-sections of the corrosion layer was investigated using scanning electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy and X-ray diffraction.

Influence of ageing treatment on microstructure, mechanical and bio-corrosion properties of Mg-Dy alloys.

Mg-Dy alloys have shown to be promising for medical applications. In order to investigate the influence of ageing treatment on their mechanical and corrosion properties, three Mg-xDy alloys (x=10, 15, 20 wt%) were prepared. Their microstructure, mechanical and corrosion behavior were investigated.

Preparation and properties of high purity Mg-Y biomaterials.

An effective zone solidification method has been found to prepare high purity Mg-Y biomaterials. The corrosion and mechanical properties of the purified middle region are improved remarkably compared with common casting method. The average gain size and secondary dendrite space decrease from the top layer to the bottom layer of the ingot.

Magnesium alloys as implant materials--principles of property design for Mg-RE alloys.

Magnesium alloys have attracted increasing interest in the past years due to their potential as implant materials. This interest is based on the fact that magnesium and its alloys are degradable during their time of service in the human body. Moreover magnesium alloys offer a property profile that is very close or even similar to that of human bone.

A graduate education framework for tropical conservation and development.

Conventional graduate training related to tropical conservation and development has typically separated the two fields, with students focusing on either conservation from the perspective of the biophysical sciences or development as an extension of the social sciences. On entering the workforce, however graduates find they are required to work beyond disciplinary boundaries to address the complex interconnectivity between biological conservation and human well-being. We devised a framework for graduate education that broadens students' skill sets to learn outside their immediate disciplines and think in terms of linked socioecological systems, work in teams, communicate in nonacademic formats, and reflect critically on their own perspectives and actions.

Demographic threats to the sustainability of Brazil nut exploitation.

A comparative analysis of 23 populations of the Brazil nut tree (Bertholletia excelsa) across the Brazilian, Peruvian, and Bolivian Amazon shows that the history and intensity of Brazil nut exploitation are major determinants of population size structure. Populations subjected to persistent levels of harvest lack juvenile trees less than 60 centimeters in diameter at breast height; only populations with a history of either light or recent exploitation contain large numbers of juvenile trees. A harvesting model confirms that intensive exploitation levels over the past century are such that juvenile recruitment is insufficient to maintain populations over the long term.

Spectral karyotyping of Werner syndrome fibroblast cultures.

Fibroblast cultures from two Werner syndrome patients were analyzed by spectral karyotyping. There were multiple, pseudodiploid clones in both cultures, mostly marked by random balanced reciprocal translocations. One of the cultures contained a clone with three-way exchanges involving chromosomes 2, 3, and 16.

Heparin-related thrombosis despite normal platelet counts in vascular surgery.

Background: Acute graft thrombosis is a severe complication in vascular surgery that may require limb amputation or even cause death. Because nearly all patients undergoing vascular surgery have had previous exposure to heparin, the presence of heparin-related anti-platelet antibodies typical for heparin-associated thrombocytopenia (HAT) is one underlying possible mechanism of acute graft thrombosis. Although thrombocytopenia is a typical finding of HAT, it is not clear whether the occurrence of clinically important HAT is necessarily associated with thrombocytopenia.

Slash pine bud dormancy as affected by lifting date and root wrenching in the nursery.

Bud dormancy of root wrenched and unwrenched slash pine (Pinus elliottii Engelm.) seedlings growing in a forest nursery was measured on five lifting dates. Determination of bud dormancy was based on days to budbreak (DBB) under optimal growing conditions, mitotic activity in the apical meristem, chilling hours accumulated, and bud morphology.