Yesterday may have been a holiday on paper, but if you were navigating LA's major freeways, there was no sign people had the day off.

Steve Julian: Business analyst Mark Lacter, is this more evidence that Southern California traffic getting worse?

Mark Lacter: Steve, L.A. continues to be the most clogged-up city in the U.S. - according to something called the TomTom Traffic Index - with commuters caught up in delays, on average, 35 percent of the time.  Or, to put it another way, L.A. commuters are in congestion up to 40 minutes of each hour they're driving.  The worst time of the week to commute is Thursday night; that's when there's congestion more than 80 percent of the time.  Monday morning commutes are the lightest.

Julian: After L.A., where should you not live if congestion bugs you?

Lacter: The next worst cities in the U.S. are San Francisco, Honolulu, Seattle, and San Jose.  Now, the Census Bureau comes up with its own commuting surveys, and if you compare the most recent numbers with those back in 2000, you'll see that things aren't all that different.  Matter of fact, the percentage of commuters driving alone to work actually increased a little over the last decade to 72 percent, while the percentage of those carpooling has declined.

Julian: What about public transit?

Lacter: Well, the numbers are up slightly from 2000, but only to 7.3 percent of all commuters.  So, even assuming that the number inches up in the next couple of years when the Expo Line extends into Santa Monica, it's still a smallish piece of the pie.  And, since many of the other public transit projects being planned are decades away from being completed, those numbers might not change much.  One other thing, Steve: less than 1 percent of all L.A. commuters bike to work, which would throw cold water on the idea that biking in L.A. is becoming a popular way of getting to the office.

Julian: People just prefer commuting by car…

Lacter: It remains the most convenient way of getting around - despite the congestion.  New car sales are up 14 percent through the first nine months of the year in Southern California.  Add to that are generally affordable gas prices (they've been especially low in the last few weeks).  In other parts of the world, congestion is considered a good thing because it means that the economy is doing well.  Which explains that while L.A. is the most congested city in the U.S., it doesn't rank among the 10 around the world.  On that front, Moscow is tops, followed by Istanbul, and Rio de Janeiro.

Julian: What about driverless cars?

Lacter: Well, these vehicles hold the most promise for reducing accidents, lowering travel times, and improving fuel economy - and you don't have to give up your car.  Actually, a lot of the technology is already in place - that includes stuff like radar-based cruise control, and devices that keep you at a safe distance from the car in front of you.  The trick, of course, is taking these individual capabilities and integrating them into an entirely driverless car.  Several car companies say they could be ready to start selling by 2020, with Google saying that its car could be ready even sooner.

Julian: Is that realistic?

Lacter: Who knows?  But even if the dates can be met - and that's a big if, considering how complex these systems are - legislatures will have to determine, among other things, whether vehicles can be fully autonomous (meaning that you can curl up and take a nap while the computer is driving by itself).  Or, whether they will only be semi-autonomous, which would be like an airline crew using automatic pilot, but always prepared to take over the controls.

Julian: Is that a liability issue?

Lacter: Yes - if something does go wrong, who will get the blame?  The owner of the vehicle?  The carmaker?  The suppliers of the car companies?  These questions might take years to get resolved in the courts - and even then, it could be years before the percentage of these vehicles on the road is large enough to truly have an impact.  But, considering that most commuters aren't willing to give up their cars, this would seem to be the most exciting, most desirable idea.  One day.

Mark Lacter writes for Los Angeles Magazine and pens the business blog at LA Observed.com.

This content is from Southern California Public Radio. View the original story at SCPR.org.

Dried specimens of nearly 800 flowering plants were acquired by the Botany Department of the Smithsonian’s National Museum of Natural History from the National Botanical Research Institute in Windhoek, Namibia, Africa. The collection includes nearly 160 specimens from the Compositae, or sunflower family.

The post Namibian specimens come to the herbarium of the National Museum of Natural History appeared first on Smithsonian Insider.

Smithsonian scientists and colleagues, however, have recently found evidence that gymnosperm plants shared an intricate pollination relationship with scorpionfly insects 62 million years before flowering plants appear in fossil records.

The post Prehistoric pollination: Scorpionfly mouthparts fit tubular channels of gymnosperm cones appeared first on Smithsonian Insider.

Since its doors first opened in 1910, the National Museum of Natural History has inspired curiosity and learning about the natural world and our place […]

The post Slide Show: Smithsonian’s National Museum of Natural History is 100! appeared first on Smithsonian Insider.

Visits to the Smithsonian's National Zoo just became a little bit sweeter with the arrival of a new honeybee colony. With a hive made of glass in the Zoo's Pollinarium and full access to the outdoors, these bees are showing off the wondrous ways of their world.

The post Honeybees fascinate visitors at the National Zoological Park appeared first on Smithsonian Insider.

Flowers are usually associated with butterflies, but not the Dutchman’s Pipe (Aristolochia grandiflora). This deciduous vine, native to Brazil, has large flowers that emit an odor of decaying flesh, which attracts flies and beetles.

The post Video: Smithsonian horticulturalist Janet Draper discusses the pollination of the pelican flower appeared first on Smithsonian Insider.

How do you recreate the ocean in a box? National Zoo Keeper Mike Henley talks about how he cares for the aquatic invertebrates in the Zoo's collection and how the National Zoo is also working to preserve them in their native habitats.

The post Coral “whisperer” Mike Henley of the National Zoo explains how he cares for the Zoo’s living coral appeared first on Smithsonian Insider.

The scientists staked out dozens of the gingers night and day while the plants flowered, but no long-proboscid pollinator ever appeared. Climate change, they surmised, was responsible for the loss of this highly specialized and now, perhaps forever unknown insect.

The post With specialist pollinator absent, Himalayan gingers must adapt appeared first on Smithsonian Insider.

The chief appeal of The Anatomy of Palms is some 800 color photographs that document the extent of palm anatomical diversity.

The post With 800 color photographs, new book takes a fascinating look inside palms appeared first on Smithsonian Insider.

The National Park Service and the Smithsonian Institution have announced a new partnership to share responsibility for selected National Park Service natural history collections, making them more readily available to researchers through the Smithsonian.

The post National Park Service natural history collections transferred to care of the Smithsonian appeared first on Smithsonian Insider.

The move enhances coordination efforts for the 46-plot research network, which partners with more than 75 institutions in 21 countries.

The post Global forest science research center moves from Harvard to the National Museum of Natural History, Washington, D.C. appeared first on Smithsonian Insider.

Do you enjoy Tequila? Then you need to raise your glass to the pollinating bats that helped to make it! Here at Smithsonian Science we […]

The post Love tequila? A toast to pollinating bats! appeared first on Smithsonian Insider.

Invertebrate Zoology Scientists studying pollinators of the yellow poppy (Meconopsis integrifolia) in the highlands of southern China have discovered a striking new species of flower fly […]

The post New species of poppy pollinating fly discovered in China appeared first on Smithsonian Insider.

Orchids are beautiful, but their beauty can be deceiving. Most orchids don’t have any nectar, yet they cheat their pollinators into thinking that they do […]

The post The Secret Life of Orchids – Part II: Pollinators appeared first on Smithsonian Insider.

Carnivorous plants are a fascinating example of nature at its best. Living in habitats with nutrient-poor soil, carnivorous plants evolved to attract some insects as […]

The post How Carnivorous Plants avoid eating their pollinating insect friends appeared first on Smithsonian Insider.

Melinda Peters, museum specialist at the U.S. National Herbarium in the Smithsonian’s National Museum of Natural History, gives an in-depth tour of the U.S. National […]

The post Introduction to the U.S. National Herbarium appeared first on Smithsonian Insider.

Named for Charles Darwin, the only known specimen of a newly discovered beetle, Darwinylus marcosi, died in a sticky battle in a gob of tree […]

The post Beetle and pollen trapped in 105 million-year-old amber reveal fourth major pollination mode in mid-Mesozoic appeared first on Smithsonian Insider.

What might lure someone away from the sunny beaches and lush forests of Brazil to the concrete jungle of Washington, D.C.? For wood anatomist Marcelo […]

The post Rigid yet flexible: Anatomy of woody vines has its grip on botanist Marcelo Pace appeared first on Smithsonian Insider.

White-tailed deer don’t like to eat the invasive plants Japanese stilt grass, garlic mustard or barberry. Native oak seedlings and tulip poplar, on the other […]

The post Too many hungry deer are lowering diversity of native plants in eastern U.S. forests appeared first on Smithsonian Insider.

“One cannot think well, love well, sleep well if one has not dined well,” Virginia Woolf once said. Woolf’s sentiment is one that the staff […]

The post Behind the scenes in the restaurant kitchen that feeds the National Zoo’s residents appeared first on Smithsonian Insider.

Each year from summer into fall, ornamental crape myrtle trees in the southern and central U.S. lay out a visual feast of vibrant flowers in […]

The post Crape myrtle trees aren’t native to the US, but hungry native birds still find them tasty appeared first on Smithsonian Insider.

This article aims to encourage practitioners, young and seasoned, by enhancing their structure-determination toolboxes with a selection of tips and tricks on recognizing and handling aspects of data collection, structure modelling and refinement, and the interpretation of results.

The crystal structure of vanthoffite, Na6Mg(SO4)4, was redetermined and refined with anisotropic displacement parameters for all atoms. Here, for the first time, we give its detailed description.

The title complex, Cu(L)2 or [Cu(C15HF10O2)2], comprising one copper ion and two fully fluorinated ligands (L−), was crystallized with 3,4-ethyl­ene­dioxy­thio­phene (EDOT, C6H6O2S) as a guest mol­ecule to give in a di­chloro­methane solution a unique co-crystal, Cu(L)2·3C6H6O2S.

An elementary method is described for finding the coordination sequences for a tiling, based on coloring the underlying graph. The first application is to the two kinds of vertices (tetravalent and trivalent) in the Cairo (or dual-32.4.3.4) tiling. The coordination sequence for a tetravalent vertex turns out, surprisingly, to be 1, 4, 8, 12, 16, …, the same as for a vertex in the familiar square (or 44) tiling. The authors thought that such a simple fact should have a simple proof, and this article is the result. The method is also used to obtain coordination sequences for the 32.4.3.4, 3.4.6.4, 4.82, 3.122 and 34.6 uniform tilings, and the snub-632 tiling. In several cases the results provide proofs for previously conjectured formulas.

It is shown how to reconstruct the stacking sequence from the pairwise correlation functions between layers in close-packed structures. First, of theoretical interest, the analytical formulation and solution of the problem are presented when the exact pairwise correlation counts are known. In the second part, the practical problem is approached. A simulated annealing procedure is developed to solve the problem using as initial guess approximate solutions from previous treatments. The robustness of the procedure is tested with synthetic data, followed by an experimental example. The developed approach performs robustly over different synthetic and experimental data, comparing favorably with the reported methods.

The crystal structure of vanthoffite {hexasodium magnesium tetrakis[sulfate(VI)]}, Na6Mg(SO4)4, was solved in the year 1964 on a synthetic sample [Fischer & Hellner (1964). Acta Cryst. 17, 1613]. Here we report a redetermination of its crystal structure on a mineral sample with improved precision. It was refined in the space group P21/c from a crystal originating from Surtsey, Iceland. The unique Mg (site symmetry overline{1}) and the two S atoms are in usual, only slightly distorted octahedral and tetrahedral coordinations, respectively. The three independent Na atoms are in a distorted octahedral coordination (1×) and distorted 7-coordinations intermediate between a `split octahedron' and a pentagonal bipyramid (2×). [MgO6] coordination polyhedra interchange with one half of the sulfate tetrahedra in <011> chains forming a (100) meshed layer, with dimers formed by edge-sharing [NaO7] polyhedra filling the interchain spaces. The other [NaO7] polyhedra are organized in a parallel layer formed by [010] and [001] chains united through edge sharing and bonds to the remaining half of sulfate groups and to [NaO6] octahedra. The two types of layers interconnect through tight bonding, which explains the lack of morphological characteristics typical of layered structures.

In small-molecule single-crystal structure determination, we now have at our disposal an inspiring range of fantastic diffractometers with better, brighter sources, and faster, more sensitive detectors. Faster and more powerful computers provide integrated tools and software with impressive graphical user interfaces. Yet these tools can lead to the temptation not to check the work thoroughly and one can too easily overlook tell-tale signs that something might be amiss in a structure determination; validation with checkCIF is not always revealing. This article aims to encourage practitioners, young and seasoned, by enhancing their structure-determination toolboxes with a selection tips and tricks on recognizing and handling aspects that one should constantly be aware of. Topics include a pitfall when setting up data collections, the usefulness of reciprocal lattice layer images, processing twinned data, tips for disorder modelling and the use of restraints, ensuring hydrogen atoms are added to a model correctly, validation beyond checkCIF, and the derivation and interpretation of the final results.

The crystal structures of caesium di­hydrogen arsenate(V) bis­[tri­hydrogen arsen­ate(V)], Cs(H2AsO4)(H3AsO4)2, ammonium di­hydrogen arsenate(V) tri­hydrogen arsenate(V), NH4(H2AsO4)(H3AsO4), and dilithium bis­(di­hydrogen phosphate), Li2(H2PO4)2, were solved from single-crystal X-ray diffraction data. NH4(H2AsO4)(H3AsO4), which was hydro­thermally synthesized (T = 493 K), is homeotypic with Rb(H2AsO4)(H3AsO4), while Cs(H2AsO4)(H3AsO4)2 crystallizes in a novel structure type and Li2(H2PO4)2 represents a new polymorph of this composition. The Cs and Li compounds grew at room temperature from highly acidic aqueous solutions. Li2(H2PO4)2 forms a three-dimensional (3D) framework of PO4 tetra­hedra sharing corners with Li2O6 dimers built of edge-sharing LiO4 groups, which is reinforced by hydrogen bonds. The two arsenate compounds are characterized by a 3D network of AsO4 groups that are connected solely via multiple strong hydrogen bonds. A statistical evaluation of the As—O bond lengths in singly, doubly and triply protonated AsO4 groups gave average values of 1.70 (2) Å for 199 As—OH bonds, 1.728 (19) Å for As—OH bonds in HAsO4 groups, 1.714 (12) Å for As—OH bonds in H2AsO4 groups and 1.694 (16) Å for As—OH bonds in H3AsO4 groups, and a grand mean value of 1.667 (18) Å for As—O bonds to nonprotonated O atoms.

During investigations of the formation of hydrated magnesium carbonates, a sample of the previously unknown magnesium carbonate hexa­hydrate (MgCO3·6H2O) was synthesized in an aqueous solution at 273.15 K. The crystal structure consists of edge-linked isolated pairs of Mg(CO3)(H2O)4 octa­hedra and noncoordinating water mol­ecules, and exhibits similarities to NiCO3·5.5H2O (hellyerite). The recorded X-ray diffraction pattern and the Raman spectra confirmed the formation of a new phase and its transformation to magnesium carbonate trihydrate (MgCO3·3H2O) at room temperature.

The com­pound poly[2-hy­droxy-N-methyl­ethan-1-aminium [μ3-cyanido-κ3C:C:N-di-μ-cyanido-κ4C:N-dicuprate(I)]], {(C3H10NO)[Cu2(CN)3]}n or [meoenH]Cu2(CN)3, crystallizes in the tetra­gonal space group P43. The structure consists of a three-dimensional (3D) anionic CuICN network with noncoordinated protonated N-methyl­ethano­lamine cations providing charge neutrality. Pairs of cuprophilic Cu atoms are bridged by the C atoms of μ3-cyanide ligands, which link these units into a 43 spiral along the c axis. The spirals are linked together into a 3D anionic network by the two other cyanide groups. The cationic moieties are linked into their own 43 spiral via N—H⋯O and O—H⋯O hydrogen bonds, and the cations inter­act with the 3D network via an unusual pair of N—H⋯N hydrogen bonds to one of the μ2-cyanide groups. Thermogravimetric analysis indicates an initial loss of the base cation and one cyanide as HCN at temperatures in the range 130–250 °C to form CuCN. We show how loss of a specific cyanide group from the 3D CuCN structure could form the linear CuCN structure. Further heating leaves a residue of elemental copper, isolated as the oxide.

The monoclinic crystal structure of Na2SO3(H2O)7 is characterized by an alternating stacking of (100) cationic sodium–water layers and anionic sulfite layers along [100]. The cationic layers are made up from two types of [Na(H2O)6] octa­hedra that form linear 1∞[Na(H2O)4/2(H2O)2/1] chains linked by dimeric [Na(H2O)2/2(H2O)4/1]2 units on both sides of the chains. The isolated trigonal–pyramidal sulfite anions are connected to the cationic layers through an intricate network of O—H⋯O hydrogen bonds, together with a remarkable O—H⋯S hydrogen bond, with an O⋯S donor–acceptor distance of 3.2582 (6) Å, which is about 0.05 Å shorter than the average for O—H⋯S hydrogen bonds in thio­salt hydrates and organic sulfur com­pounds of the type Y—S—Z (Y/Z = C, N, O or S). Structural relationships between monoclinic Na2SO3(H2O)7 and ortho­rhom­bic Na2CO3(H2O)7 are discussed in detail.

Quaternion methods for obtaining solutions to the problem of finding global rotations that optimally align pairs of corresponding lists of 3D spatial and/or orientation data are critically studied. The existence of multiple literatures and historical contexts is pointed out, and the algebraic solutions of the quaternion approach to the classic 3D spatial problem are emphasized. The treatment is extended to novel quaternion-based solutions to the alignment problems for 4D translation and orientation data.

Canada-based digital transaction processor Carta Worldwide teamed with

Cancer-causing chemicals that occur naturally in foods are far more numerous in the human diet than synthetic carcinogens, yet both types are consumed at levels so low that they currently appear to pose little threat to human health, a committee of the National Research Council said in a report released today.

A bold national initiative is needed to reduce the enormous health burden of sexually transmitted diseases (STDs) in the United States, according to a new report from a committee of the Institute of Medicine.

Smokers who are exposed to radon appear to be at even greater risk for lung cancer, because the effects of smoking and radon are more powerful when the two factors are combined, says a new report by a committee of the National Research Council.

Outdated food safety laws and a fragmented federal structure serve as barriers to improving protection of the nations food supply from contamination or other hazards, according to Ensuring Safe Food From Production to Consumption.

No justification currently exists for completely abandoning chemical pesticides, says a new report from the National Academies National Research Council.

Scientific evidence is insufficient to prove or disprove the theory that exposure to polio vaccine contaminated with a monkey virus between 1955 and 1963 has triggered cancer in humans, says a new report from the Institute of Medicine of the National Academies.

As the recent spread of West Nile virus and the anthrax scare of 2001 dramatically illustrate, America faces a variety of new health challenges in the 21st century, along with a number of persistent problems, such as racial disparities in health status and care delivery.

The environmental effects of oil and gas exploration and production on Alaska s North Slope have been accumulating for more than three decades, says a new report from the National Academies National Research Council.

Welcome to the public release of the latest Institute of Medicine report on the quality of health care in America.

To significantly reduce the tens of thousands of deaths and injuries caused by medical errors every year, health care organizations must adopt information technology systems that are capable of collecting and sharing essential health information on patients and their care, says a new report by the Institute of Medicine of the National Academies.

Nearly half of all American adults – 90 million people – have difficulty understanding and using health information, and there is a higher rate of hospitalization and use of emergency services among patients with limited health literacy, says a new report from the Institute of Medicine of the National Academies.

The National Academies have bestowed the title of Education Fellow in the Life Sciences to 42 educators around the country who successfully completed a summer institute aimed at fostering innovative approaches to teaching undergraduate biology.