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基因分型“芯片”将促进珊瑚保护行动 快报文章
资源环境快报,2020年第18期
作者:  薛明媚,王金平
Microsoft Word(20Kb)  |  收藏  |  浏览/下载:405/0  |  提交时间:2020/09/29
Coral  genotyping array  
Massively multiplexed nucleic acid detection with Cas13 期刊论文
NATURE, 2020, 582 (7811) : 277-+
作者:  Mahato, Biraj;  Kaya, Koray Dogan;  Fan, Yan;  Sumien, Nathalie;  Shetty, Ritu A.;  Zhang, Wei;  Davis, Delaney;  Mock, Thomas;  Batabyal, Subrata;  Ni, Aiguo;  Mohanty, Samarendra;  Han, Zongchao;  Farjo, Rafal;  Forster, Michael J.;  Swaroop, Anand;  Chavala, Sai H.
收藏  |  浏览/下载:82/0  |  提交时间:2020/07/03

CRISPR-based nucleic acid detection is used in a platform that can simultaneously detect 169 human-associated viruses in multiple samples, providing scalable, multiplexed pathogen detection aimed at routine surveillance for public health.


The great majority of globally circulating pathogens go undetected, undermining patient care and hindering outbreak preparedness and response. To enable routine surveillance and comprehensive diagnostic applications, there is a need for detection technologies that can scale to test many samples(1-3)while simultaneously testing for many pathogens(4-6). Here, we develop Combinatorial Arrayed Reactions for Multiplexed Evaluation of Nucleic acids (CARMEN), a platform for scalable, multiplexed pathogen detection. In the CARMEN platform, nanolitre droplets containing CRISPR-based nucleic acid detection reagents(7)self-organize in a microwell array(8)to pair with droplets of amplified samples, testing each sample against each CRISPR RNA (crRNA) in replicate. The combination of CARMEN and Cas13 detection (CARMEN-Cas13) enables robust testing of more than 4,500 crRNA-target pairs on a single array. Using CARMEN-Cas13, we developed a multiplexed assay that simultaneously differentiates all 169 human-associated viruses with at least 10 published genome sequences and rapidly incorporated an additional crRNA to detect the causative agent of the 2020 COVID-19 pandemic. CARMEN-Cas13 further enables comprehensive subtyping of influenza A strains and multiplexed identification of dozens of HIV drug-resistance mutations. The intrinsic multiplexing and throughput capabilities of CARMEN make it practical to scale, as miniaturization decreases reagent cost per test by more than 300-fold. Scalable, highly multiplexed CRISPR-based nucleic acid detection shifts diagnostic and surveillance efforts from targeted testing of high-priority samples to comprehensive testing of large sample sets, greatly benefiting patients and public health(9-11).


  
A biomimetic eye with a hemispherical perovskite nanowire array retina 期刊论文
NATURE, 2020, 581 (7808) : 278-+
作者:  Hueckel, Theodore;  Hocky, Glen M.;  Palacci, Jeremie;  Sacanna, Stefano
收藏  |  浏览/下载:75/0  |  提交时间:2020/07/03

A biomimetic electrochemical eye is presented that has a hemispherical retina made from a high-density array of perovskite nanowires that are sensitive to light, mimicking the photoreceptors of a biological retina.


Human eyes possess exceptional image-sensing characteristics such as an extremely wide field of view, high resolution and sensitivity with low aberration(1). Biomimetic eyes with such characteristics are highly desirable, especially in robotics and visual prostheses. However, the spherical shape and the retina of the biological eye pose an enormous fabrication challenge for biomimetic devices(2,3). Here we present an electrochemical eye with a hemispherical retina made of a high-density array of nanowires mimicking the photoreceptors on a human retina. The device design has a high degree of structural similarity to a human eye with the potential to achieve high imaging resolution when individual nanowires are electrically addressed. Additionally, we demonstrate the image-sensing function of our biomimetic device by reconstructing the optical patterns projected onto the device. This work may lead to biomimetic photosensing devices that could find use in a wide spectrum of technological applications.


  
Operation of a silicon quantum processor unit cell above one kelvin 期刊论文
NATURE, 2020, 580 (7803) : 350-+
作者:  Han, Kyuho;  Pierce, Sarah E.;  Li, Amy;  Spees, Kaitlyn;  Anderson, Grace R.;  Seoane, Jose A.;  Lo, Yuan-Hung;  Dubreuil, Michael;  Olivas, Micah;  Kamber, Roarke A.;  Wainberg, Michael;  Kostyrko, Kaja;  Kelly, Marcus R.;  Yousefi, Maryam;  Simpkins, Scott W.;  Yao, David
收藏  |  浏览/下载:26/0  |  提交时间:2020/07/03

Quantum computers are expected to outperform conventional computers in several important applications, from molecular simulation to search algorithms, once they can be scaled up to large numbers-typically millions-of quantum bits (qubits)(1-3). For most solid-state qubit technologies-for example, those using superconducting circuits or semiconductor spins-scaling poses a considerable challenge because every additional qubit increases the heat generated, whereas the cooling power of dilution refrigerators is severely limited at their operating temperature (less than 100 millikelvin)(4-6). Here we demonstrate the operation of a scalable silicon quantum processor unit cell comprising two qubits confined to quantum dots at about 1.5 kelvin. We achieve this by isolating the quantum dots from the electron reservoir, and then initializing and reading the qubits solely via tunnelling of electrons between the two quantum dots(7-9). We coherently control the qubits using electrically driven spin resonance(10,11) in isotopically enriched silicon(12 28)Si, attaining single-qubit gate fidelities of 98.6 per cent and a coherence time of 2 microseconds during '  hot'  operation, comparable to those of spin qubits in natural silicon at millikelvin temperatures(13-16). Furthermore, we show that the unit cell can be operated at magnetic fields as low as 0.1 tesla, corresponding to a qubit control frequency of 3.5 gigahertz, where the qubit energy is well below the thermal energy. The unit cell constitutes the core building block of a full-scale silicon quantum computer and satisfies layout constraints required by error-correction architectures(8),(17). Our work indicates that a spin-based quantum computer could be operated at increased temperatures in a simple pumped He-4 system (which provides cooling power orders of magnitude higher than that of dilution refrigerators), thus potentially enabling the integration of classical control electronics with the qubit array(18,19).


  
Copper-mediated synthesis of drug-like bicyclopentanes 期刊论文
NATURE, 2020, 580 (7802) : 220-+
作者:  Canavelli, Pierre;  Islam, Saidul;  Powner, Matthew W.
收藏  |  浏览/下载:12/0  |  提交时间:2020/07/03

Multicomponent reactions are relied on in both academic and industrial synthetic organic chemistry owing to their step- and atom-economy advantages over traditional synthetic sequences(1). Recently, bicyclo[1.1.1]pentane (BCP) motifs have become valuable as pharmaceutical bioisosteres of benzene rings, and in particular 1,3-disubstituted BCP moieties have become widely adopted in medicinal chemistry as para-phenyl ring replacements(2). These structures are often generated from [1.1.1]propellane via opening of the internal C-C bond through the addition of either radicals or metal-based nucleophiles(3-13). The resulting propellane-addition adducts are then transformed to the requisite polysubstituted BCP compounds via a range of synthetic sequences that traditionally involve multiple chemical steps. Although this approach has been effective so far, a multicomponent reaction that enables single-step access to complex and diverse polysubstituted drug-like BCP products would be more time efficient compared to current stepwise approaches. Here we report a one-step three-component radical coupling of [1.1.1]propellane to afford diverse functionalized bicyclopentanes using various radical precursors and heteroatom nucleophiles via a metallaphotoredox catalysis protocol. This copper-mediated reaction operates on short timescales (five minutes to one hour) across multiple (more than ten) nucleophile classes and can accommodate a diverse array of radical precursors, including those that generate alkyl, alpha-acyl, trifluoromethyl and sulfonyl radicals. This method has been used to rapidly prepare BCP analogues of known pharmaceuticals, one of which is substantially more metabolically stable than its commercial progenitor.


A one-step, three-component radical coupling of [1.1.1]propellane by a photoredox reaction mediated by a copper catalyst produces drug-like bicyclopentanes.


  
PIK3CA variants selectively initiate brain hyperactivity during gliomagenesis 期刊论文
NATURE, 2020, 578 (7793) : 166-+
作者:  Qiu, Chaorui;  Wang, Bo;  Zhang, Nan;  Zhang, Shujun;  Liu, Jinfeng;  Walker, David;  Wang, Yu;  Tian, Hao;  Shrout, Thomas R.;  Xu, Zhuo;  Chen, Long-Qing;  Li, Fei
收藏  |  浏览/下载:33/0  |  提交时间:2020/07/03

Glioblastoma is a universally lethal form of brain cancer that exhibits an array of pathophysiological phenotypes, many of which are mediated by interactions with the neuronal microenvironment(1,2). Recent studies have shown that increases in neuronal activity have an important role in the proliferation and progression of glioblastoma(3,4). Whether there is reciprocal crosstalk between glioblastoma and neurons remains poorly defined, as the mechanisms that underlie how these tumours remodel the neuronal milieu towards increased activity are unknown. Here, using a native mouse model of glioblastoma, we develop a high-throughput in vivo screening platform and discover several driver variants of PIK3CA. We show that tumours driven by these variants have divergent molecular properties that manifest in selective initiation of brain hyperexcitability and remodelling of the synaptic constituency. Furthermore, secreted members of the glypican (GPC) family are selectively expressed in these tumours, and GPC3 drives gliomagenesis and hyperexcitability. Together, our studies illustrate the importance of functionally interrogating diverse tumour phenotypes driven by individual, yet related, variants and reveal how glioblastoma alters the neuronal microenvironment.


Glioblastoma tumours expressing oncogenic PIK3CA variants secrete the glycan GPC3, which promotes the formation of neural synapses, brain synaptic hyperexcitability and gliomagenesis.


  
ROOTS OF MENTAL ILLNESS 期刊论文
NATURE, 2020, 581 (7806) : 19-21
作者:  Sohn, Emily
收藏  |  浏览/下载:17/0  |  提交时间:2020/07/03

Psychiatrists have a dizzying array of diagnoses and not enough treatments. Hunting for the hidden biology underlying mental disorders could help.


Psychiatrists have a dizzying array of diagnoses and not enough treatments. Hunting for the hidden biology underlying mental disorders could help.


  
The pheromone darcin drives a circuit for innate and reinforced behaviours 期刊论文
NATURE, 2020, 578 (7793) : 137-+
作者:  Du, Zhiguo;  Yang, Shubin;  Li, Songmei;  Lou, Jun;  Zhang, Shuqing;  Wang, Shuai;  Li, Bin;  Gong, Yongji;  Song, Li;  Zou, Xiaolong;  Ajayan, Pulickel M.
收藏  |  浏览/下载:43/0  |  提交时间:2020/07/03

Organisms have evolved diverse behavioural strategies that enhance the likelihood of encountering and assessing mates(1). Many species use pheromones to communicate information about the location, sexual and social status of potential partners(2). In mice, the major urinary protein darcin-which is present in the urine of males-provides a component of a scent mark that elicits approach by females and drives learning(3,4). Here we show that darcin elicits a complex and variable behavioural repertoire that consists of attraction, ultrasonic vocalization and urinary scent marking, and also serves as a reinforcer in learning paradigms. We identify a genetically determined circuit-extending from the accessory olfactory bulb to the posterior medial amygdala-that is necessary for all behavioural responses to darcin. Moreover, optical activation of darcin-responsive neurons in the medial amygdala induces both the innate and the conditioned behaviours elicited by the pheromone. These neurons define a topographically segregated population that expresses neuronal nitric oxide synthase. We suggest that this darcin-activated neural circuit integrates pheromonal information with internal state to elicit both variable innate behaviours and reinforced behaviours that may promote mate encounters and mate selection.


A neural circuit activated by the male pheromone, darcin, mediates a complex and variable array of innate and reinforced behaviours that may promote mate encounters and mate selection.


  
Meteorological Aspects of Self-Initiated Upward Lightning at the Santis Tower (Switzerland) 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2019, 124 (24) : 14162-14183
作者:  Pineda, Nicolau;  Figueras i Ventura, Jordi;  Romero, David;  Mostajabi, Amirhossein;  Azadifar, Mohammad;  Sunjerga, Antonio;  Rachidi, Farhad;  Rubinstein, Marcos;  Montanya, Joan;  van der Velde, Oscar A.;  Altube, Patricia;  Besic, Nikola;  Grazioli, Jacopo;  Germann, Urs;  Williams, Earle R.
收藏  |  浏览/下载:18/0  |  提交时间:2020/02/17
self-initiated upward lightning  Lightning Mapping Array  polarimetric weather radar  Hydrometeor Classification Product  upward propagating leader  
A Three-Dimensional Array for the Study of Infrasound Propagation Through the Atmospheric Boundary Layer 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2019, 124 (16) : 9299-9313
作者:  Smink, Madelon M. E.;  Assink, Jelle D.;  Bosveld, Fred C.;  Smets, Pieter S. M.;  Evers, Laeslo G.
收藏  |  浏览/下载:10/0  |  提交时间:2019/11/27
infrasound  atmospheric boundary layer  array processing  propagation modeling  atmospheric models