抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

https://www.cs.princeton.edu/~schapire/papers/ecolmod.pdf

Maximum entropy modeling of species geographic distributions

Prediction of species' distributions is central to diverse applications in ecology, evolution and conservation science. There is increasing electronic access to vast sets of occurrence records in museums and herbaria, yet little effective guidance on how best to use this information in the context of numerous approaches for modelling distributions. To meet this need, we compared 16 modelling methods over 226 species from 6 regions of the world, creating the most comprehensive set of model comparisons to date. We used presence-only data to fit models, and independent presence-absence data to evaluate the predictions. Along with well-established modelling methods such as generalised additive models and GARP and BIOCLIM, we explored methods that either have been developed recently or have rarely been applied to modelling species' distributions. These include machine-learning methods and community models, both of which have features that may make them particularly well suited to noisy or sparse information, as is typical of species' occurrence data. Presence-only data were effective for modelling species' distributions for many species and regions. The novel methods consistently outperformed more established methods. The results of our analysis are promising for the use of data from museums and herbaria, especially as methods suited to the noise inherent in such data improve.

/pdf/novel-methods-improve-prediction-of-species-distributions-3cmioqeu6v.pdf

Novel methods improve prediction of species' distributions from occurrence data

The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.

/pdf/planetary-boundaries-guiding-human-development-on-a-changing-5gmf909etg.pdf

Planetary boundaries: Guiding human development on a changing planet

1 Late twentieth-century patterns and trends in the climate of tropical forest regions 3 Yadvinder Malhi and James Wright 2 Twenty-first century atmospheric change and deforestation: potential impacts on tropical forests 17 Wolfgang Cramer, Alberte Bondeau, Sibyll Schaphoff, Wolfgang Lucht, Ben Smith, and Stephen Sitch 3 Forest-climate interactions in fragmented tropical landscapes 31 William F. Laurance

The prospects for tropical forests in the twenty-first-century atmosphere

Abstract Although tropical forests differ substantially in form and function, they are often represented as a single biome in global change models, hindering understanding of how different tropical forests will respond to environmental change. The response of the tropical forest biome to environmental change is strongly influenced by forest type. Forest types differ based on functional traits and forest structure, which are readily derived from high resolution airborne remotely sensed data. Whether the spatial resolution of emerging satellite-derived hyperspectral data is sufficient to identify different tropical forest types is unclear. Here, we resample airborne remotely sensed forest data at spatial resolutions relevant to satellite remote sensing (30 m) across two sites in Malaysian Borneo. Using principal component and cluster analysis, we derive and map seven forest types. We find ecologically relevant variations in forest type that correspond to substantial differences in carbon stock, growth, and mortality rate. We find leaf mass per area and canopy phosphorus are critical traits for distinguishing forest type. Our findings highlight the importance of these parameters for accurately mapping tropical forest types using space borne observations. 

/pdf/mapping-tropical-forest-functional-variation-at-satellite-1jhgdosc.pdf

Mapping tropical forest functional variation at satellite remote sensing resolutions depends on key traits

Species richness, tropical forest dynamics, and sampling:

Ecosystems worldwide are changing as a result of anthropogenic activities. Processes such as deforestation are physically obvious, but others, such as hunting and surface fires, are subtler but affect biodiversity in insidious ways (cf. Lewis et al., 2004a; Laurance, 2004). Increased rates of nitrogen deposition and increases in air temperatures and atmospheric CO2 concentrations are altering the environment of even the largest and most well-protected areas (e.g., Galloway and Cowling, 2002; Malhi and Wright, 2004). Anthropogenic atmospheric change will become more significant during this century, as CO2 concentrations reach levels unprecedented for the last 20 million or perhaps even 40 million years (Retallack, 2001; Royer et al., 2001). Nitrogen deposition rates and climates are predicted to move far beyond Quaternary envelopes (Galloway and Cowling, 2002). Moreover, the rate of change in all these basic ecological drivers is likely to be without precedent in the evolutionary span of most species on Earth today (Lewis et al., 2004a). This then is the Anthropocene: we are living through truly epoch-making times (Crutzen, 2002).

The response of South American tropical forests to recent atmospheric changes

Registramos a 729 especies agrupadas en 120 familias con 398 generos entre arboles, lianas, arbustos, hierbas, hemiepifitos y epifitos. Caracterizamos la vegetacion del area en cinco tipos de bosque: Llanura amazonica, Transicional pre-Montano, pre-Montano, Nublado o Montano alto y el Esclerofilo; sobre ellos establecimos, 6 parcelas permanentes con la finalidad de implementar un sistema de monitoreo de la dinamica de los bosques. El mayor contenido de biomasa aerea se halla sobre el bosque transicional pre-Montano con 264 T/ha. La vegetacion sobre el llano amazonico aparentemente presenta una dinamica mas estable, donde las tasas de reclutamiento y mortalidad fluctuan entre los 2.4 y 2%. La mayor diversidad vegetal ocurre sobre los bosques de Llanura amazonica. El mayor area basal ocupado por los individuos de la parcela III, con 31.7 m², un area menor es ocupado por los arboles de la parcela IV con solo 3 m². La estructura horizontal, esta dado mayormente por arboles cuyos diametros fluctuan entre los 10 y 30 cm de diametro, en las parcelas I, II, III, y V. En cambio la parcela IV, sigue el mismo patron de distribucion, pero el mayor numero de individuos se encuentran agrupados entre 5 a 15 cm de diametro. La estructura vertical esta dada por arboles de 5 a 10 m de alto, que forman el sotobosque, seguido de aquellos que tienen alturas >10-15 m, que forman el dosel y el grupo de los arboles emergentes conformados por individuos cuyas alturas fluctuan entre los 15 y 25 m de alto

/pdf/linea-base-para-el-monitoreo-de-la-vegetacion-en-la-reserva-3vlsvkfbnz.pdf

Oliver L. Phillips

Papers

The prospects for tropical forests in the twenty-first-century atmosphere

Mapping tropical forest functional variation at satellite remote sensing resolutions depends on key traits

Species richness, tropical forest dynamics, and sampling:

The response of South American tropical forests to recent atmospheric changes

Línea base para el monitoreo de la vegetación en la reserva comunal el sira (rcs)