Contents
Vol 337, Issue 6094
Special Issue
Black Holes
Introduction to Special Issue
Perspectives
Reviews
Contents
This Week in Science
Editorial
Editors' Choice
Multimedia
- Cover Stories: Cygnus X-1—The Bigger Picture
Astronomy illustrators must use science and artistry to present objects that will never be seen with the naked eye.
Podcasts
- Science Podcast
The show includes the quantum mechanics of black holes, analyzing elephant vocalizations, and chasing down the last of the polio virus.
Products & Materials
- New Products
A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.
News of the Week
- Around the World
In science news around the world this week, a dengue vaccine shows promise, a U.S. court says stem cells are drugs, a fracking report is under scrutiny, Germany's National Academy of Sciences Leopoldina has come down firmly against the use of crops for energy, and a Senate panel last week approved a bill that would ban invasive research on great apes in the United States.
- Random Sample
The world's largest telescope to observe the highest energy photons from space saw its first light in Namibia last week. An orchid called Acampe rigida seems to be the first discovered that depends on rain to pollinate its flowers. And this week's numbers quantify HIV-infected U.S. men who have sex with men, low-income countries that will become middle-income by 2020, and the speed of cheetahs and ducks.
- Newsmakers
This week's Newsmaker is paleobotanist Kirk Johnson, who was named the new director of the Smithsonian Institution National Museum of Natural History.
Findings
News & Analysis
- Dreams Meet Realities at AIDS Conference
The 19th International AIDS Conference, held in Washington, D.C., from 22 to 27 July, marked the meeting's return to the United States for the first time in 22 years.
- Multicellularity Driven by Bacteria
Bacteria can prompt single-celled choanoflagellates to divide into multicellular versions of themselves, biologists reported last week at the 71st annual meeting of the Society for Developmental Biology.
- NASA's Spacefaring Science Chief Sets a New Course for Mars
Science spoke to John Grunsfeld, head of NASA's Science Mission Directorate, days before what he calls the science event of the decade: the 5 August (PDT) landing of Curiosity on the martian surface.
- Ice Age Tools Hint at 40,000 Years of Bushman Culture
Archaeologists studying a South African cave say they have found 44,000-year-old artifacts—including bone tools and poisoned arrowheads—nearly identical to those still in use by hunter-gatherers.
- London's Olympic Drug Testing Lab to Become National Phenome Center
The U.K. Medical Research Council and the National Institute for Health Research will transform the Olympic antidoping laboratory into a national center dedicated to metabolic phenotyping.
News Focus
- The Polio Emergency
Can a tough new taskmaster and ramped-up program finally push the global eradication initiative over the finish line?
- Fighting Polio in Pakistan
Pakistan's 18-year struggle shows why it is so hard to eradicate polio from its last few strongholds.
- Closing a Deadly Refuge
On 17 July in the town of Gadap in Karachi, Pakistan, two gunmen shot at two men who were participating in a national polio vaccination campaign—sadly, a not uncommon occurrence.
Letters
Books et al.
- Left and Right, Right and Wrong
Haidt offers a provocative account of the psychological foundations of morality and how they lead to political conflicts.
- On Our Biocultural Nature
Fuentes dissects various widely held but scientifically unsupported beliefs about human sex, aggression, and race.
Policy Forum
- Aligning Regulations and Ethics in Human Research
New U.S. rules should ensure assessment of subjects' understanding, compensation for injury, and standards of study quality.
Perspectives
- Outsourcing Genome Protection
Small RNAs repress transposons by triggering the formation of another class of small RNAs that silence transposon targets.
- Approaching Asymmetry and Versatility in Polymer Assembly
Multistep solution processes can create polymeric nanoparticles that are asymmetrical and that have complex internal structures.
- Modular Biological Complexity
Understanding how vast numbers of heterogeneous components behave in biological systems requires consideration of their interactions as modules.
- How Did the Cuckoo Get Its Polymorphic Plumage?
As reed warblers learn to avoid the threat from cuckoos resembling sparrow hawks, they remain under threat from differently colored cuckoos.
- F. Herbert Bormann (1922–2012)
An ecologist's relentless focus on large-scale studies of watersheds played a key role in identifying human impacts on forests.
Review
Brevia
- Cartwheel Architecture of Trichonympha Basal Body
Electron microscopy provides a close-up view of the ninefold-symmetric stacked rings at the base of cilia and flagella.
Reports
- Radio Detections During Two State Transitions of the Intermediate-Mass Black Hole HLX-1
Observations of a candidate intermediate-mass black hole support the scale invariance of jets in black holes.
- Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities
The Kepler spacecraft detected a super-Earth and a Neptune-like planet in very tightly spaced orbits around the same star.
- Non-Centrosymmetric Cylindrical Micelles by Unidirectional Growth
A capping approach is used to create asymmetrical block copolymer micelles through self-assembly.
- A Reversible and Higher-Rate Li-O2 Battery
A viable lithium-oxygen battery is demonstrated using dimethylsulfoxide electrolyte and a porous gold cathode.
- Aerosols from Overseas Rival Domestic Emissions over North America
Roughly half of all particulate matter found in the air above North America originates from sources overseas.
- Aerial Photographs Reveal Late–20th-Century Dynamic Ice Loss in Northwestern Greenland
Archived photographs extending back to the mid-1980s help show the role of dynamic thinning in ice mass loss from Greenland.
- Function, Targets, and Evolution of Caenorhabditis elegans piRNAs
Piwi-bound piwi-interacting RNAs recruit endogenous small interfering RNAs to silence mobile genetic elements.
- Cuckoos Combat Socially Transmitted Defenses of Reed Warbler Hosts with a Plumage Polymorphism
Parasitic cuckoos sporting new colors flourish after their warbler hosts learn to defend against the mainstream fashion.
- Unraveling the Life History of Successful Invaders
Allocating resources to long-lived adults is one means by which birds succeed in new niches.
- Quantitative Modulation of Polycomb Silencing Underlies Natural Variation in Vernalization
Arabidopsis adjusts the onset of flowering to the length of winters via an epigenetic mechanism.
- Mitochondrial Import Efficiency of ATFS-1 Regulates Mitochondrial UPR Activation
When stressed, the mitochondrion reduces import of a transcription factor, which enters the nucleus instead.
- Opening and Closing of the Bacterial RNA Polymerase Clamp
Single-molecule fluorescence measurements define the clamp conformation during transcription initiation and elongation.
- How Low Can You Go? Physical Production Mechanism of Elephant Infrasonic Vocalizations
Elephants produce low-frequency sounds via intrinsic vocal-fold vibrations similar to those in humans.
- Feedback Regulation of Transcriptional Termination by the Mammalian Circadian Clock PERIOD Complex
A circadian rhythm regulator acts by altering the elongation stage of gene expression.