The observation that decision trees are boosting algorithms, as cited in our work (1) and acknowledged by Nock and Nielsen (2), was first established by refs. 3 and 4. This was later used by refs. 5 and 6 to develop, to the best of our knowledge, the first decision tree...
12h
Ultrashort light pulses can selectively excite charges, spins, and phonons in materials, providing a powerful approach for manipulating their properties. Here we use femtosecond laser pulses to coherently manipulate the electron and phonon distributions, and their couplings, in the charge-density wave (CDW) material 1T-TaSe2. After exciting the material with a...
12h
Schmukle et al. (1) conducted informative conceptual replications of our finding that economic inequality moderates the relationship between income and generosity (2). Schmukle et al. (1) did not find that inequality moderates associations between income and self-reported charitable donations (study 1), first- and second-mover trust game allocations (study 2), and...
12h
International carbon markets are an appealing and increasingly popular tool to regulate carbon emissions. By putting a price on carbon, carbon markets reshape incentives faced by firms and reduce the value of emissions. How effective are carbon markets? Observers have tended to infer their effectiveness from market prices. The general...
12h
Côté et al. (1) provided evidence that economic inequality moderates the effect of income on generosity. In their study, individuals with higher household income were less generous in a dictator game than poorer individuals only if they resided in a US state with comparatively large economic inequality. We questioned this...
12h
The interplay of transcription factors and cis-regulatory elements (CREs) orchestrates the dynamic and diverse genetic programs that assemble the human central nervous system (CNS) during development and maintain its function throughout life. Genetic variation within CREs plays a central role in phenotypic variation in complex traits including the risk of...
12h
A key feature in the evolution of multicellular organisms was the development of complex vascular systems to transport resources from sites of primary acquisition to sites of usage and storage. In plants, leaves generate the energy required to sustain multicellular growth through the reactions of photosynthesis, and much of that...
12h
Current multiple sclerosis (MS) medications are mainly immunomodulatory, having little or no effect on neuroregeneration of damaged central nervous system (CNS) tissue; they are thus primarily effective at the acute stage of disease, but much less so at the chronic stage. An MS therapy that has both immunomodulatory and neuroregenerative...
12h
Natural photosynthetic systems and photocatalysis share several fundamental processes in common including light energy conversion and utilization, such as exciton (excited state) generation/splitting and charge migration. The high efficiency of light conversion to chemical redox equivalents in natural photosynthesis is achieved by an electron transfer cascade resulting in a long-distance...
12h
We report five studies that examine preferences for the allocation of environmental harms and benefits. In all studies, participants were presented with scenarios in which an existing environmental inequality between two otherwise similar communities could either be decreased or increased through various allocation decisions. Our results demonstrate that despite well-established...
12h
Proteins perform a spectrum of functions inside the cell, ranging from energy utilization to enzymatic activity to signaling, as well as structural and mechanical roles, among many others. Substantial research efforts throughout the years have focused on understanding these phenomena at the molecular level as well as the evolutionary processes...
12h
Composites are ideally suited to achieve desirable multifunctional effective properties since the best properties of different materials can be judiciously combined with designed microstructures. Here, we establish cross-property relations for two-phase composite media that link effective elastic and electromagnetic wave characteristics to one another, including the respective effective wave speeds...
12h
The Greek island of Santorini (named Thera in ancient times) is located in the Aegean Sea and experienced a massive volcanic eruption some 3,600 y ago (∼1600 BCE). Recent geological investigations have concluded that the eruption was even more massive than originally thought (1). This eruption is commonly referred to...
12h
The bacterial flagellum is an amazing nanomachine. Understanding how such complex structures arose is crucial to our understanding of cellular evolution. We and others recently reported that in several Gammaproteobacterial species, a relic subcomplex comprising the decorated P and L rings persists in the outer membrane after flagellum disassembly. Imaging...
12h
Polyketide synthases (PKSs) assemble activated carboxylic acids to elaborate chemical compounds (1). The key synthetic step is the C-C bond-forming condensation of an acyl moiety (e.g., acetyl-coenzyme A [CoA]) with an α-carboxyacyl moiety (e.g., malonyl-CoA) on release of CO2. The emerging β-ketoacyl compound can optionally be further modified by three...
12h
The disposable soma theory is a central tenet of the biology of aging where germline immortality comes at the cost of an aging soma [T. B. L. Kirkwood, Nature 270, 301–304 (1977); T. B. L. Kirkwood, Proc. R. Soc. Lond. B Biol. Sci. 205, 531–546 (1979); T. B. L. Kirkwood,...
12h
Eastern equine encephalitis virus (EEEV), a mosquito-borne icosahedral alphavirus found mainly in North America, causes human and equine neurotropic infections. EEEV neurovirulence is influenced by the interaction of the viral envelope protein E2 with heparan sulfate (HS) proteoglycans from the host’s plasma membrane during virus entry. Here, we present a...
12h
The vast majority of type 1 diabetes (T1D) genetic association signals lie in noncoding regions of the human genome. Many have been predicted to affect the expression and secondary structure of long noncoding RNAs (lncRNAs), but the contribution of these lncRNAs to the pathogenesis of T1D remains to be clarified....
12h
April 22, 2020, marks the 50th anniversary of Earth Day and the birth of the modern environmental movement. As we look back over the past half century, we can gain significant insights into the evolving human imprint on Earth’s biophysical systems, and the role of science and scientists in driving...
12h
The invasive behavior of glioblastoma is essential to its aggressive potential. Here, we show that pleckstrin homology domain interacting protein (PHIP), acting through effects on the force transduction layer of the focal adhesion complex, drives glioblastoma motility and invasion. Immunofluorescence analysis localized PHIP to the leading edge of glioblastoma cells,...
12h
Here we describe the development of a humidity-responsive sheet of paper that is derived solely from natural pollen. Adaptive soft material components of the paper exhibit diverse and well-integrated responses to humidity that promote shape reconfiguration, actuation, and locomotion. This mechanically versatile and nonallergenic paper can generate a cyclically high...
12h
Under certain conditions, a fermion in a superconductor can separate in space into two parts known as Majorana zero modes, which are immune to decoherence from local noise sources and are attractive building blocks for quantum computers. Promising experimental progress has been made to demonstrate Majorana zero modes in materials...
12h
Micron-scale robots require systems that can morph into arbitrary target configurations controlled by external agents such as heat, light, electricity, and chemical environment. Achieving this behavior using conventional approaches is challenging because the available materials at these scales are not programmable like their macroscopic counterparts. To overcome this challenge, we...
12h
Plant auxin response factor (ARF) transcription factors are an important class of key transcriptional modulators in auxin signaling. Despite the well-studied roles of ARF transcription factors in plant growth and development, it is largely unknown whether, and how, ARF transcription factors may be involved in plant resistance to pathogens. We...
12h
The genetic incorporation of noncanonical amino acids (ncAAs) into proteins has been realized in bacteria, yeast, and mammalian cells, and recently, in multicellular organisms including plants and animals. However, the addition of new building blocks to the genetic code of tissues from human origin has not yet been achieved. To...
12h
Deportation has become more commonplace in the United States since the mid-2000s. Latin American noncitizens—encompassing undocumented and documented immigrants—are targeted for deportation. Deportation’s threat also reaches naturalized and US-born citizens of Latino descent who are largely immune to deportation but whose loved ones or communities are deportable. Drawing on 6...
12h
Closthioamide (CTA) is a rare example of a thioamide-containing nonribosomal peptide and is one of only a handful of secondary metabolites described from obligately anaerobic bacteria. Although the biosynthetic gene cluster responsible for CTA production and the thioamide synthetase that catalyzes sulfur incorporation were recently discovered, the logic for peptide...
12h
Multiple-choice examinations play a critical role in university admissions across the world. A key question is whether imposing penalties for wrong answers on these examinations deters guessing from women more than men, disadvantaging female test-takers. We consider data from a large-scale, high-stakes policy change that removed penalties for wrong answers...
12h
To repair a DNA double-strand break by homologous recombination, 5′-terminated DNA strands must first be resected to reveal 3′-overhangs. This process is initiated by a short-range resection catalyzed by MRE11-RAD50-NBS1 (MRN) stimulated by CtIP, which is followed by a long-range step involving EXO1 or DNA2 nuclease. DNA2 is a bifunctional...
12h
The European continent was subject to two major migrations of peoples during the Holocene: the northwestward movement of Anatolian farmer populations during the Neolithic and the westward movement of Yamnaya steppe peoples during the Bronze Age. These movements changed the genetic composition of the continent’s inhabitants. The Holocene was also...
12h
Rapid methods for diagnosis of bacterial infections are urgently needed to reduce inappropriate use of antibiotics, which contributes to antimicrobial resistance. In many rapid diagnostic methods, DNA oligonucleotide probes, attached to a surface, bind to specific nucleotide sequences in the DNA of a target pathogen. Typically, each probe binds to...
12h
The timing of human colonization of East Polynesia, a vast area lying between Hawai‘i, Rapa Nui, and New Zealand, is much debated and the underlying causes of this great migration have been enigmatic. Our study generates evidence for human dispersal into eastern Polynesia from islands to the west from around...
12h
The ability to precisely design large proteins with diverse shapes would enable applications ranging from the design of protein binders that wrap around their target to the positioning of multiple functional sites in specified orientations. We describe a protein backbone design method for generating a wide range of rigid fusions...
12h
Stomatopod crustaceans possess some of the most complex animal visual systems, including at least 16 spectrally distinct types of photoreceptive units (e.g., assemblages of photoreceptor cells). Here we fully characterize the set of opsin genes expressed in retinal tissues and determine expression patterns of each in the stomatopod Neogonodactylus oerstedii....
12h
Microtubules (MTs) are essential components of the eukaryotic cytoskeleton that serve as “highways” for intracellular trafficking. In addition to the well-known active transport of cargo by motor proteins, many MT-binding proteins seem to adopt diffusional motility as a transportation mechanism. However, because of the limited spatial resolution of current experimental...
12h
Identifying marine or freshwater fossils that belong to the stem groups of the major terrestrial arthropod radiations is a longstanding challenge. Molecular dating and fossils of their pancrustacean sister group predict that myriapods originated in the Cambrian, much earlier than their oldest known fossils, but uncertainty about stem group Myriapoda...
12h
One of the most intriguing features of biological systems is their ability to regulate the steady-state fluxes of the underlying biochemical reactions; however, the regulatory mechanisms and their physicochemical properties are not fully understood. Fundamentally, flux regulation can be explained with a chemical kinetic formalism describing the transitions between discrete...
12h
Polyploidy, which results from whole genome duplication (WGD), has shaped the long-term evolution of eukaryotic genomes in all kingdoms. Polyploidy is also implicated in adaptation, domestication, and speciation. Yet when WGD newly occurs, the resulting neopolyploids face numerous challenges. A particularly pernicious problem is the segregation of multiple chromosome copies...
12h
Performance tradeoffs are ubiquitous in both ecological and evolutionary modeling, yet they are usually postulated and built into fitness and ecological landscapes. However, tradeoffs depend on genetic background and evolutionary history and can themselves evolve. We present a simple model capable of capturing the key feedback loop: evolutionary history shapes...
12h
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