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Author

Jens H. Gundlach

Other affiliations: Illumina
Bio: Jens H. Gundlach is an academic researcher from University of Washington. The author has contributed to research in topics: Nanopore & Nanopore sequencing. The author has an hindex of 37, co-authored 116 publications receiving 8860 citations. Previous affiliations of Jens H. Gundlach include Illumina.


Papers
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Journal ArticleDOI
TL;DR: It is found with 95% confidence that the inverse-square law holds (|alpha|
Abstract: We conducted three torsion-balance experiments to test the gravitational inverse-square law at separations between 9.53 mm and $55\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$, probing distances less than the dark-energy length scale ${\ensuremath{\lambda}}_{d}=\sqrt[4]{\ensuremath{\hbar}c/{\ensuremath{\rho}}_{d}}\ensuremath{\approx}85\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$. We find with 95% confidence that the inverse-square law holds ($|\ensuremath{\alpha}|\ensuremath{\le}1$) down to a length scale $\ensuremath{\lambda}=56\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ and that an extra dimension must have a size $R\ensuremath{\le}44\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$.

919 citations

Journal ArticleDOI
TL;DR: The ability to resolve changes in current that correspond to a known DNA sequence is demonstrated by combining the high sensitivity of a mutated form of the protein pore Mycobacterium smegmatis porin A with phi29 DNA polymerase (DNAP), which controls the rate of DNA translocation through the pore.
Abstract: Nanopore technologies are being developed for fast and direct sequencing of single DNA molecules through detection of ionic current modulations as DNA passes through a pore's constriction. Here we demonstrate the ability to resolve changes in current that correspond to a known DNA sequence by combining the high sensitivity of a mutated form of the protein pore Mycobacterium smegmatis porin A (MspA) with phi29 DNA polymerase (DNAP), which controls the rate of DNA translocation through the pore. As phi29 DNAP synthesizes DNA and functions like a motor to pull a single-stranded template through MspA, we observe well-resolved and reproducible ionic current levels with median durations of ∼28 ms and ionic current differences of up to 40 pA. Using six different DNA sequences with readable regions 42-53 nucleotides long, we record current traces that map to the known DNA sequences. With single-nucleotide resolution and DNA translocation control, this system integrates solutions to two long-standing hurdles to nanopore sequencing.

815 citations

Journal ArticleDOI
TL;DR: By analyzing the data for accelerations towards the center of the Milky Way the authors find equal attractions of Be and Ti towards galactic dark matter, yielding eta(DM,Be-Ti)=(-4+/-7)x10(-5).
Abstract: We used a continuously rotating torsion balance instrument to measure the acceleration difference of beryllium and titanium test bodies towards sources at a variety of distances. Our result Δa N,Be-Ti = (0.6 ± 3.1) X 10 -15 m/s 2 improves limits on equivalence-principle violations with ranges from 1 m to ∞ by an order of magnitude. The Eotvos parameter is η Earth,Be-Ti = (0.3 ± 1.8) X 10 -13 . By analyzing our data for accelerations towards the center of the Milky Way we find equal attractions of Be and Ti towards galactic dark matter, yielding η DM,Be-Ti = (∼4 ± 7) X 10 -5 . Space-fixed differential accelerations in any direction are limited to less than 8.8 X 10 -15 m/s 2 with 95% confidence.

643 citations

Journal ArticleDOI
TL;DR: It is demonstrated that the ionic current through the engineered Mycobacterium smegmatis porin A, MspA, has the ability to distinguish all four DNA nucleotides and resolve single-nucleotides in single- Stranded DNA when double-stranded DNA temporarily holds the nucleotide in the pore constriction.
Abstract: Nanopore sequencing has the potential to become a direct, fast, and inexpensive DNA sequencing technology. The simplest form of nanopore DNA sequencing utilizes the hypothesis that individual nucleotides of single-stranded DNA passing through a nanopore will uniquely modulate an ionic current flowing through the pore, allowing the record of the current to yield the DNA sequence. We demonstrate that the ionic current through the engineered Mycobacterium smegmatis porin A, MspA, has the ability to distinguish all four DNA nucleotides and resolve single-nucleotides in single-stranded DNA when double-stranded DNA temporarily holds the nucleotides in the pore constriction. Passing DNA with a series of double-stranded sections through MspA provides proof of principle of a simple DNA sequencing method using a nanopore. These findings highlight the importance of MspA in the future of nanopore sequencing.

575 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组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�ly.
Abstract: 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。

18,940 citations

01 Jan 2011
TL;DR: To understand the central claims of evolutionary psychology the authors require an understanding of some key concepts in evolutionary biology, cognitive psychology, philosophy of science and philosophy of mind.
Abstract: 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.

4,670 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a review of the most important aspects of the different classes of modified gravity theories, including higher-order curvature invariants and metric affine.
Abstract: 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.

4,027 citations

Journal ArticleDOI
TL;DR: A comprehensive survey of recent work on modified theories of gravity and their cosmological consequences can be found in this article, where the authors provide a reference tool for researchers and students in cosmology and gravitational physics, as well as a selfcontained, comprehensive and up-to-date introduction to the subject as a whole.

3,674 citations

Journal ArticleDOI
TL;DR: 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.
Abstract: 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.

3,394 citations