Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Although these six elements make up nucleic acids, proteins, and lipids and thus the bulk of living ...matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here, we describe a bacterium, strain GFAJ-1 of the Halomonadaceae, isolated from Mono Lake, California, that is able to substitute arsenic for phosphorus to sustain its growth. Our data show evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. Exchange of one of the major bio-elements may have profound evolutionary and geochemical importance.
Stereotype Threat Spencer, Steven J; Logel, Christine; Davies, Paul G
Annual review of psychology,
01/2016, Letnik:
67, Številka:
1
Journal Article
Recenzirano
When members of a stigmatized group find themselves in a situation where negative stereotypes provide a possible framework for interpreting their behavior, the risk of being judged in light of those ...stereotypes can elicit a disruptive state that undermines performance and aspirations in that domain. This situational predicament, termed stereotype threat, continues to be an intensely debated and researched topic in educational, social, and organizational psychology. In this review, we explore the various sources of stereotype threat, the mechanisms underlying stereotype-threat effects (both mediators and moderators), and the consequences of this situational predicament, as well as the means through which society and stigmatized individuals can overcome the insidious effects of stereotype threat. Ultimately, we hope this review alleviates some of the confusion surrounding stereotype threat while also sparking further research and debate.
The ability of platinum and gold catalysts to effect powerful atom‐economic transformations has led to a marked increase in their utilization. The quite remarkable correlation of their catalytic ...behavior with the available structural data, coordination chemistry, and organometallic reactivity patterns, including relativistic effects, allows the underlying principles of catalytic carbophilic activation by π acids to be formulated. The spectrum of reactivity extends beyond their utility as catalytic and benign alternatives to conventional stoichiometric π acids. The resulting reactivity profile allows this entire field of catalysis to be rationalized, and brings together the apparently disparate electrophilic metal carbene and nonclassical carbocation explanations. The advances in coupling, cycloisomerization, and structural reorganization—from the design of new transformations to the improvement to known reactions—are highlighted in this Review. The application of platinum‐ and gold‐catalyzed transformations in natural product synthesis is also discussed.
The reactivity of π‐acidic metal catalysts has been correlated to known structural data. Through this comparison, the apparently disparate electrophilic metal carbene and nonclassical carbocation explanations (see picture), used in the literature to rationalize the diverse range of transformations possible under platinum and gold catalysis, come together under a reactivity profile through which this field may be rationalized.
The algorithmic origins of life Walker, Sara Imari; Davies, Paul C. W.
Journal of the Royal Society interface,
02/2013, Letnik:
10, Številka:
79
Journal Article
Recenzirano
Odprti dostop
Although it has been notoriously difficult to pin down precisely what is it that makes life so distinctive and remarkable, there is general agreement that its informational aspect is one key ...property, perhaps the key property. The unique informational narrative of living systems suggests that life may be characterized by context-dependent causal influences, and, in particular, that top-down (or downward) causation—where higher levels influence and constrain the dynamics of lower levels in organizational hierarchies—may be a major contributor to the hierarchal structure of living systems. Here, we propose that the emergence of life may correspond to a physical transition associated with a shift in the causal structure, where information gains direct and context-dependent causal efficacy over the matter in which it is instantiated. Such a transition may be akin to more traditional physical transitions (e.g. thermodynamic phase transitions), with the crucial distinction that determining which phase (non-life or life) a given system is in requires dynamical information and therefore can only be inferred by identifying causal architecture. We discuss some novel research directions based on this hypothesis, including potential measures of such a transition that may be amenable to laboratory study, and how the proposed mechanism corresponds to the onset of the unique mode of (algorithmic) information processing characteristic of living systems.
Quantum aspects of life Abbott, Derek; Devies, Paul C. W; Pati, Arun K
2008., 2008, 2008-09-12
eBook
This book presents the hotly debated question of whether quantum mechanics plays a non-trivial role in biology. In a timely way, it sets out a distinct quantum biology agenda. The burgeoning fields ...of nanotechnology, biotechnology, quantum technology, and quantum information processing are now strongly converging. The acronym BINS, for Bio-Info-Nano-Systems, has been coined to describe the synergetic interface of these several disciplines.
The hidden simplicity of biology Davies, Paul C W; Walker, Sara Imari
Reports on progress in physics,
10/2016, Letnik:
79, Številka:
10
Journal Article
Recenzirano
Life is so remarkable, and so unlike any other physical system, that it is tempting to attribute special factors to it. Physics is founded on the assumption that universal laws and principles ...underlie all natural phenomena, but is it far from clear that there are 'laws of life' with serious descriptive or predictive power analogous to the laws of physics. Nor is there (yet) a 'theoretical biology' in the same sense as theoretical physics. Part of the obstacle in developing a universal theory of biological organization concerns the daunting complexity of living organisms. However, many attempts have been made to glimpse simplicity lurking within this complexity, and to capture this simplicity mathematically. In this paper we review a promising new line of inquiry to bring coherence and order to the realm of biology by focusing on 'information' as a unifying concept.
Police shooting deaths of unarmed Blacks and African Americans led to psychological research on the influence of racial stereotypes on decisions to shoot, an effect called shooter bias. This article ...investigates how contextual cues signaling threat or safety interact with the race of the target to moderate shooter bias. Across two experimental studies using a first person shooter task, participants viewed Black or White male targets who held either a neutral (wallet or cellphone) or dangerous (gun) object. Study 1 manipulated the perceived safety or threat associated with the neighborhood context these shooting decisions occurred in, and Study 2 manipulated the perceived safety or threat associated with the targets’ clothing. Participants made quick decisions to “shoot” or “not shoot” the presented target, with error rates serving as the dependent variable. Across both studies, results confirmed that racial bias in shooting decisions against Blacks was present in perceived threatening neighborhoods and in perceived threatening clothing, and it was reduced in perceived safe neighborhoods and when wearing perceived safe clothing. Results help to identify contextual factors that may lead to mistaken shooting decisions, which can be used to improve police training and decision making to reduce bias.
Oxazole new world: A gold‐catalyzed intermolecular reaction of pyridine‐N‐aminides with ynamides can be used to prepare trisubstituted 1,3‐oxazoles with a variety of functional groups. This formal ...3+2 cycloaddition employs robust conjugated N‐ylides as N‐nucleophilic N‐acyl nitrene equivalents for a highly chemoselective and regioselective addition across electron‐rich CC triple bonds.
The informational architecture of the cell Walker, Sara Imari; Kim, Hyunju; Davies, Paul C. W.
Philosophical transactions - Royal Society. Mathematical, Physical and engineering sciences/Philosophical transactions - Royal Society. Mathematical, physical and engineering sciences,
03/2016, Letnik:
374, Številka:
2063
Journal Article
Recenzirano
Odprti dostop
We compare the informational architecture of biological and random networks to identify informational features that may distinguish biological networks from random. The study presented here focuses ...on the Boolean network model for regulation of the cell cycle of the fission yeast Schizosaccharomyces pombe. We compare calculated values of local and global information measures for the fission yeast cell cycle to the same measures as applied to two different classes of random networks: Erdös-Rényi and scale-free. We report patterns in local information processing and storage that do indeed distinguish biological from random, associated with control nodes that regulate the function of the fission yeast cell-cycle network. Conversely, we find that integrated information, which serves as a global measure of 'emergent' information processing, does not differ from random for the case presented. We discuss implications for our understanding of the informational architecture of the fission yeast cell-cycle network in particular, and more generally for illuminating any distinctive physics that may be operative in life.
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