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

Evolutionary psychology is one of many biologically informed approaches to the study of human behavior. Along with cognitive psychologists, evolutionary psychologists propose that much, if not all, of our behavior can be explained by appeal to internal psychological mechanisms. What distinguishes evolutionary psychologists from many cognitive psychologists is the proposal that the relevant internal mechanisms are adaptations—products of natural selection—that helped our ancestors get around the world, survive and reproduce. To understand the central claims of evolutionary psychology we require an understanding of some key concepts in evolutionary biology, cognitive psychology, philosophy of science and philosophy of mind. Philosophers are interested in evolutionary psychology for a number of reasons. For philosophers of science —mostly philosophers of biology—evolutionary psychology provides a critical target. There is a broad consensus among philosophers of science that evolutionary psychology is a deeply flawed enterprise. For philosophers of mind and cognitive science evolutionary psychology has been a source of empirical hypotheses about cognitive architecture and specific components of that architecture. Philosophers of mind are also critical of evolutionary psychology but their criticisms are not as all-encompassing as those presented by philosophers of biology. Evolutionary psychology is also invoked by philosophers interested in moral psychology both as a source of empirical hypotheses and as a critical target.

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Stanford Encyclopedia of Philosophy

Modified gravity theories have received increased attention lately due to combined motivation coming from high-energy physics, cosmology, and astrophysics. Among numerous alternatives to Einstein's theory of gravity, theories that include higher-order curvature invariants, and specifically the particular class of $f(R)$ theories, have a long history. In the last five years there has been a new stimulus for their study, leading to a number of interesting results. Here $f(R)$ theories of gravity are reviewed in an attempt to comprehensively present their most important aspects and cover the largest possible portion of the relevant literature. All known formalisms are presented---metric, Palatini, and metric affine---and the following topics are discussed: motivation; actions, field equations, and theoretical aspects; equivalence with other theories; cosmological aspects and constraints; viability criteria; and astrophysical applications.

f ( R ) theories of gravity

Modified Gravity and Cosmology

The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein’s equivalence principle (EEP) is well supported by experiments such as the Eotvos experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.

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The Confrontation Between General Relativity and Experiment

We have built a highly sensitive torsion balance to investigate small forces between closely spaced gold coated surfaces. Such forces will occur between the LISA proof mass and its housing. These forces are not well understood and experimental investigations are imperative. We describe our torsion balance and present the noise of the system. A significant contribution to the LISA noise budget at low frequencies is the fluctuation in the surface potential difference between the proof mass and its housing. We present first results of these measurements with our apparatus.

High Sensitivity Torsion Balance Tests for LISA Proof Mass Modeling

We describe a torsion pendulum with a large mass-quadrupole moment and a resonant frequency of 2.8 mHz, whose angle is measured using a modified Michelson interferometer. The system achieved noise levels of $\sim200\ \text{prad}/\sqrt{\text{Hz}}$ between 0.2-30 Hz and $\sim10\ \text{prad}/\sqrt{\text{Hz}}$ above 100 Hz. Such a system can be applied to a broad range of fields from the study of rotational seismic motion and elastogravity signals to gravitational wave observation and tests of gravity.

A Low-Frequency Torsion Pendulum with Interferometric Readout

The thermal noise of a torsion balance is determined by the mechanical quality factor Q of its fiber, where higher‐Q fibers are less noisy. We report here on the fabrication and characterization of fused quartz and fused silica torsion fibers with Qs as high as 3.6 × 105 at frequencies below 0.1 Hz. Fibers as small as 10 μm in diameter were made conducting with thin metal coatings while retaining Qs larger than 104. Pressure‐dependent damping was discerned at pressures lower than 10−5 Pa, suggesting residual gas damping may limit experiments using these higher‐Q fibers.

Quality Factors of Bare and Metal‐Coated Quartz and Fused Silica Torsion Fibers

Erratum: Radiative decays of the 16.6 and 16.9 MeV states in Be8 and tests of the conservation of the vector current in the A=8 multiplet (Physical Review C (1995) 51 (2778))

We have measured inclusive {gamma}-ray production cross sections for {sup 3}He- and {alpha}-induced reactions on various targets in the mass range {ital A}=61{endash}181 at projectile energies of 11{endash}27 MeV. Except for {alpha}-induced yields on the lightest targets, all reactions show high-energy {gamma}-ray yields 1{endash}3 orders of magnitude larger than can be obtained from statistical model calculations. Angular distributions are strongly forward peaked in the center of mass frame for the highest {gamma}-ray energies, providing model-independent evidence for a nonstatistical reaction mechanism. Calculations of direct radiative capture and semidirect excitation of the giant dipole resonance can qualitatively reproduce the angular distributions but cannot reproduce either the dependence of the {gamma}-ray cross sections on {ital E}{sub {gamma}} or the target dependence of the absolute cross sections. The {sup 12}C({sup 3}He,{gamma}{sub 0}){sup 15}O reaction was found to change from predominantly statistical to predominantly direct over this bombarding energy range. {copyright} {ital 1996 The American Physical Society.}

Jens H. Gundlach

Papers

High Sensitivity Torsion Balance Tests for LISA Proof Mass Modeling

A Low-Frequency Torsion Pendulum with Interferometric Readout

Quality Factors of Bare and Metal‐Coated Quartz and Fused Silica Torsion Fibers

Erratum: Radiative decays of the 16.6 and 16.9 MeV states in Be8 and tests of the conservation of the vector current in the A=8 multiplet (Physical Review C (1995) 51 (2778))

Nonstatistical gamma emission in 3He- and alpha -induced reactions.