Tropical forests speed their own recovery, capturing nitrogen and carbon faster after being logged or cleared for agriculture. Researchers working at the Smithsonian Tropical Research […]

The post Tropical forests “fix” themselves appeared first on Smithsonian Insider.

Tucked into the wooded landscape and rolling hills of the Smithsonian Environmental Research Center in Edgewater, Md., is a new forest. Six months ago, a […]

The post Century-long Smithsonian experiment tests forest diversity appeared first on Smithsonian Insider.

In deer-populated forests, tastier plants can avoid being eaten if they are surrounded by less appealing plants. But with deer gone, diverse plots become weaker […]

The post Diverse forests are stronger against deer appeared first on Smithsonian Insider.

Tropical forests are a sometimes underappreciated asset in the battle against climate change. They cover 7 percent of land surface yet hold more than 30 […]

The post Vine-choked forests can’t capture carbon appeared first on Smithsonian Insider.

A 57-acre research plot at a University of Michigan forest preserve northwest of Ann Arbor has been added to a Smithsonian Institution global network used […]

The post University of Michigan forest preserve joins Smithsonian global network appeared first on Smithsonian Insider.

On March 26, 1912, a donation from Japan arrived in Washington, D.C.―3,020 ornamental cherry trees, sparking one of the biggest springtime annual attractions in the […]

The post Washington, D.C.’s Cherry Trees are Very Good at Planning for the Future appeared first on Smithsonian Insider.

“When you can’t breathe, nothing else matters,” once a tagline of the American Lung Association, today it might easily describe what is happening in many […]

The post Gasping for air: nutrients, warming trigger ocean oxygen deficit appeared first on Smithsonian Insider.

On crime scene investigation shows, forensic scientists use remnants of genetic material to solve mysteries in a matter of hours. Researchers at the Smithsonian Environmental […]

The post Environmental “Forensics” Pieces Together Mysterious Plant Invasion appeared first on Smithsonian Insider.

In a study published Sept. 28 in the journal Nature Plants, a team led by Smithsonian Conservation Biology Institute scientists found that bigger trees suffer […]

The post Forest Giants Suffer Most During Droughts appeared first on Smithsonian Insider.

Although useful to Tarzan, vines endanger tropical forests’ capacity to store carbon. In a major experimental study in Panama, Smithsonian researchers showed that woody vines, […]

The post Climbing plants disturb carbon storage in tropical forests appeared first on Smithsonian Insider.

This year’s El Niño event is one of the strongest on record and is still ramping up. Large parts of the tropics are turning into […]

The post Major El Nino Perfect opportunity for Global Change Research appeared first on Smithsonian Insider.

How much is a wetland worth? It’s a question that has plagued policymakers, scientists and other leaders looking to protect their communities and slow down […]

The post New report enables creation of carbon credits for restored wetlands appeared first on Smithsonian Insider.

Fort Pierce, Fla. – Fall in southern Florida is festival season: when the weather stops being oppressively hot and 70 degrees is positively autumnal.  On […]

The post Annual Smithsonian-led science festival draws crowds in Fort Pierce, Florida appeared first on Smithsonian Insider.

Federal agencies act as custodians of hundreds of diverse scientific collections that contain everything from plant and animal specimens, tissues, and DNA to microbes, minerals, […]

The post One-Stop Shopping for Federal Scientific Collections appeared first on Smithsonian Insider.

Rainforests on infertile wet soils support more than half of all plant species. Shrublands on infertile dry soils in southwestern Australia, jokingly called “knee-high tropical […]

The post Microbes rule in ‘knee-high tropical rainforests’ appeared first on Smithsonian Insider.

The Smithsonian is joining with local communities and the Nigerian Montane Forest Project to better understand and conserve montane forests in Nigeria.

The post Taking the Pulse of Our Planet’s Forests: appeared first on Smithsonian Insider.

Most of us can’t begin the day without a cup of coffee. Coffee is a major agricultural crop in many Central and South American countries […]

The post A Cup of Joe That’s Also Good for the Birds appeared first on Smithsonian Insider.

Smithsonian scientists have discovered two new gecko species—the Lenya banded bent-toed gecko (Cyrtodactylus lenya) and Tenasserim Mountain bent-toed gecko (C. payarhtanesnsis)—in the little-studied lowland forests […]

The post Smithsonian Scientists Discover Two New Gecko Species in Vanishing Myanmar Rainforest appeared first on Smithsonian Insider.

This Earth Day weekend in Washington, D.C., the Smithsonian is convening the first Earth Optimism Summit. The three-day event, taking place April 21–23, will look […]

The post Earth Optimism: Smithsonian’s “Agua Salud” Project restores degraded land with forest appeared first on Smithsonian Insider.

Is it foolish to be optimistic about our environment and its future prospects? Every day, we hear dire warnings about the health of the planet […]

The post The Argument for Environmental Optimism: Opinion by Smithsonian Secretary David J. Skorton appeared first on Smithsonian Insider.

Zebra mussels in the Great Lakes, lionfish in the Atlantic and pythons in the Everglades: Large creatures like these generally draw the spotlight when talking […]

The post DNA is trusty new weapon for detecting slime nets and other invasive marine parasites appeared first on Smithsonian Insider.

A tiny invasive insect from Asia might have an effect on Chesapeake Bay waters. The emerald ash borer is killing millions of ash trees in […]

The post Invasive ash borer found in Smithsonian Environmental Research Center forest; ash deaths may impact Chesapeake waters appeared first on Smithsonian Insider.

The post Global forest network cracks the case of tropical biodiversity appeared first on Smithsonian Insider.

(A male golden-collared manakin cleans up his display area.) Few of us would find a marriage proposal made amidst dirty dishes and messy clutter particularly […]

The post Clean = Sexy for this Panamanian Bird 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.

According to a new study by biologists at the Smithsonian Migratory Bird Center and Virginia Tech the offspring of a certain songbird, the wood thrush, […]

The post Study: Large shady forest plots essential to survival of post-fledgling songbirds during drought appeared first on Smithsonian Insider.

Camouflage is a valuable survival strategy—just ask a chameleon. Scientists have just discovered a new form of mimicry camouflage: beetles that hide by chewing beetle-shaped […]

The post For millions of years these tiny beetles have chewed their way out of sight appeared first on Smithsonian Insider.

The report of the Executive Committee for 2017 is presented.

This work presents a technique for extracting the detailed shape of peaks with extended, overlapping tails in an X-ray powder diffraction pattern. The application discussed here concerns crystallite size broadening, though the technique can be applied to spectra of any origin and without regard to how the profiles are to be subsequently analyzed. Historically, the extraction of profile shapes has been difficult due to the complexity of determining the background under the peak, resulting in an offset of the low-frequency components of the Fourier transform of the peak known as the `hook' problem. The use of a carefully considered statistical weighting function in a non-linear least-squares fit, followed by summing the residuals from such a fit with the fit itself, allows one to extract the full shape of an isolated peak, without contributions from either the background or adjacent peaks. The extracted shape, consisting of the fit function recombined with the residuals, is not dependent on any specific shape model. The application of this to analysis of microstructure is performed independently of global parametric models, which would reduce the number of refined parameters; therefore the technique requires high-quality data to produce results of interest. The effectiveness of the technique is demonstrated by extraction of Fourier transforms of peaks from two sets of size-broadened materials with two differing pieces of equipment.

The unit-cell reduction described by Selling and used by Delone (whose early publications were under the spelling Delaunay) is explained in a simple form. The transformations needed to implement the reduction are listed. The simplicity of this reduction contrasts with the complexity of Niggli reduction.

The methods for X-ray crystal orientation are rapidly evolving towards versatility, fewer goniometry measurements, automation, high accuracy and precision. One method that attracts a lot of attention is energy-dispersive X-ray diffraction (EDXRD) which is based on detecting reflections from crystallographic planes in a crystal at fixed angles of a parallel polychromatic X-ray incident beam. In theory, an EDXRD peak can move in a diffraction pattern as a function of a crystallographic plane d-spacing and its orientation relative to a fixed direction in space can change also. This is equivalent to the possibility of measuring the orientation of single crystals. The article provides a modeling for the EDXRD method whose main feature is the nonmoving crystal in the sense of traditional goniometry where the angle measurements of diffracting planes are a must. The article defines the equation of orientation for the method and shows the derivation in great detail. It is shown that the exact solutions of the equations can be obtained using the generalized reduced gradient method, a mathematical subroutine that is implemented in Excel software. The significance and scientific impact of the work are discussed along with the validated tested results.

A new aspherical scattering factor formalism has been implemented in the crystallographic least-squares refinement program SHELXL. The formalism relies on Gaussian functions and can optionally complement the independent atom model to take into account the deformation of electron-density distribution due to chemical bonding and lone pairs. Asphericity contributions were derived from the electron density obtained from quantum-chemical density functional theory computations of suitable model compounds that contain particular chemical environments, as defined by the invariom formalism. Thanks to a new algorithm, invariom assignment for refinement in SHELXL is automated. A suitable parameterization for each chemical environment within the new model was achieved by metaheuristics. Figures of merit, precision and accuracy of crystallographic least-squares refinements improve significantly upon using the new model.

This work considers the scaling properties characterizing the hyperuniformity (or anti-hyperuniformity) of long-wavelength fluctuations in a broad class of one-dimensional substitution tilings. A simple argument is presented which predicts the exponent α governing the scaling of Fourier intensities at small wavenumbers, tilings with α > 0 being hyperuniform, and numerical computations confirm that the predictions are accurate for quasiperiodic tilings, tilings with singular continuous spectra and limit-periodic tilings. Quasiperiodic or singular continuous cases can be constructed with α arbitrarily close to any given value between −1 and 3. Limit-periodic tilings can be constructed with α between −1 and 1 or with Fourier intensities that approach zero faster than any power law.

In a Model block, if the instance-specific value of a model argument has an anonymous structure type, an update diagram reports an error when there are multiple bus types that match that anonymous structure type.This bug exists in the following release(s):
R2020a

This bug has a workaround

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