The reactions of N-heterocyclic carbene CuI and AgI halides with potassium thio- or seleno­cyanate gave unexpected products. The attempted substitution reaction of bromido­(1,3-dibenzyl-4,5-di­phenyl­imidazol-2-yl­idene)silver (NHC*—Ag—Br) with KSCN yielded bis­[bis­(1,3-dibenzyl-4,5-di­phenyl­imidazol-2-yl­idene)silver(I)] tris­(thio­cyanato)­argentate(I) diethyl ether disolvate, [Ag(C29H24N2)2][Ag(NCS)3]·2C4H10O or [NHC*2Ag]2[Ag(SCN)3]·2Et2O, (1), while reaction with KSeCN led to bis­(μ-1,3-dibenzyl-4,5-diphenyl-2-seleno­imidazole-κ2Se:Se)bis­[bromido­(1,3-dibenzyl-4,5-diphenyl-2-seleno­imid­azole-κSe)silver(I)] di­chloro­methane hexa­solvate, [Ag2Br2(C29H24N2Se)4]·6CH2Cl2 or (NHC*Se)4Ag2Br2·6CH2Cl2, (2), via oxidation of the NHC* fragment to 2-seleno­imidazole. This oxidation was observed again in the reaction of NHC*—Cu—Br with KSeCN, yielding catena-poly[[[(1,3-dibenzyl-4,5-diphenyl-2-seleno­imidazole-κSe)copper(I)]-μ-cyanido-κ2C:N] aceto­nitrile monosolvate], {[Cu(CN)(C29H24N2Se)]·C2H3N}n or NHC*Se—CuCN·CH3CN, (3). Compound (1) represents an organic/inorganic salt with AgI in a linear coordination in each of the two cations and in a trigonal coordination in the anion, accompanied by diethyl ether solvent mol­ecules. The tri-blade boomerang-shaped complex anion [Ag(SCN)3]2− present in (1) is characterized by X-ray diffraction for the first time. Compound (2) comprises an isolated centrosymmetric mol­ecule with AgI in a distorted tetra­hedral BrSe3 coordination, together with di­chloro­methane solvent mol­ecules. Compound (3) exhibits a linear polymeric 1∞[Cu—C≡N—Cu—] chain structure with a seleno­imidazole moiety additionally coordinating to each CuI atom, and completed by aceto­nitrile solvent mol­ecules. Electron densities associated with an additional ether solvent mol­ecule in (1) and two additional di­chloro­methane solvent mol­ecules in (2) were removed with the SQUEEZE procedure [Spek (2015). Acta Cryst. C71, 9–18] in PLATON.

In the title com­pound, C30H20Cl2O2Se, the C—Se—C angle is 99.0 (2)°, with the dihedral angle between the planes of the attached benzene rings being 79.1 (3)°. The average endocyclic angles (Se—C—C) facing the Se atom are 122.1 (5) and 122.2 (5)°. The Se atom is essentially coplanar with the attached benzene rings, deviating by 0.075 (1) and 0.091 (1) Å. In the two phenyl­ene(4-chloro­phen­yl)prop-2-en-1-one units, the benzene rings are inclined to each other by 44.6 (3) and 7.8 (3)°. In the crystal, the mol­ecules stack up the a axis, forming layers parallel to the ac plane. There are no significant classical inter­molecular inter­actions present. Hirshfeld surface analysis, two-dimensional fingerprint plots and the mol­ecular electrostatic potential surface were used to analyse the crystal packing. The Hirshfeld surface analysis suggests that the most significant contributions to the crystal packing are by C⋯H/H⋯C contacts (17.7%).

The reaction of [Se8][B12F11NH3]2 with acetone and subsequent crystallization from acetone/diethyl ether yielded the selenium cation [Se(CH2C(O)CH3)3]+ as a by-product, which is stabilized by the weakly coordinating undeca­fluorinated anion [B12F11NH3]−. While attempting to crystallize pure [Se8][B12F11NH3]2, the structure of the isolated product, namely, tris­(2-oxoprop­yl)selenium 1-ammonio­undeca­fluoro­dodeca­borate, was surprising. The cation [Se(CH2C(O)CH3)3]+ represents the first example for a cationic selenium compound with three ketone functional groups located in the β-position with respect to the selenium atom. The cation possesses almost trigonal–pyramidal C3 symmetry and forms hydrogen bonds to the ammonio group of the anion.

The structural dimension of metal–organic frameworks (MOFs) is of great importance in defining their properties and thus applications. In particular, 2D layered MOFs are of considerable interest because of their useful applications, which are facilitated by unique structural features of 2D materials, such as a large number of open active sites and high surface areas. Herein, this work demonstrates a methodology for the selective synthesis of a 2D layered MOF in the presence of the competitive formation of a 3D MOF. The ratio of the reactants, metal ions and organic building blocks used during the reaction is found to be critical for the selective formation of a 2D MOF, and is associated with its chemical composition. In addition, the well defined and uniform micro-sized 2D MOF particles are successfully synthesized in the presence of an ultrasonic dispersion. Moreover, the laminated 2D MOF layers are directly synthesized via a modified bottom-up lamination method, a combination of chemical and physical stimuli, in the presence of surfactant and ultrasonication.

The disposition of functional groups can induce variations in the nature and type of interactions and hence affect the molecular recognition and self-assembly mechanism in cocrystals. To better understand the formation of cocrystals on a molecular level, the effects of disposition of functional groups on the formation of cocrystals were systematically and comprehensively investigated using cresol isomers (o-, m-, p-cresol) as model compounds. Consistency and variability in these cocrystals containing positional isomers were found and analyzed. The structures, molecular recognition and self-assembly mechanism of supramolecular synthons in solution and in their corresponding cocrystals were verified by a combined experimental and theoretical calculation approach. It was found that the heterosynthons (heterotrimer or heterodimer) combined with O—H⋯N hydrogen bonding played a significant role. Hirshfeld surface analysis and computed interaction energy values were used to determine the hierarchical ordering of the weak interactions. The quantitative analyses of charge transfers and molecular electrostatic potential were also applied to reveal and verify the reasons for consistency and variability. Finally, the molecular recognition, self-assembly and evolution process of the supramolecular synthons in solution were investigated. The results confirm that the supramolecular synthon structures formed initially in solution would be carried over to the final cocrystals, and the supramolecular synthon structures are the precursors of cocrystals and the information memory of the cocrystallization process, which is evidence for classical nucleation theory.

Olfactomedins are a family of modular proteins found in multicellular organisms that all contain five-bladed β-propeller olfactomedin (OLF) domains. In support of differential functions for the OLF propeller, the available crystal structures reveal that only some OLF domains harbor an internal calcium-binding site with ligands derived from a triad of residues. For the myocilin OLF domain (myoc-OLF), ablation of the ion-binding site (triad Asp, Asn, Asp) by altering the coordinating residues affects the stability and overall structure, in one case leading to misfolding and glaucoma. Bioinformatics analysis reveals a variety of triads with possible ion-binding characteristics lurking in OLF domains in invertebrate chordates such as Arthropoda (Asp–Glu–Ser), Nematoda (Asp–Asp–His) and Echinodermata (Asp–Glu–Lys). To test ion binding and to extend the observed connection between ion binding and distal structural rearrangements, consensus triads from these phyla were installed in the myoc-OLF. All three protein variants exhibit wild-type-like or better stability, but their calcium-binding properties differ, concomitant with new structural deviations from wild-type myoc-OLF. Taken together, the results indicate that calcium binding is not intrinsically destabilizing to myoc-OLF or required to observe a well ordered side helix, and that ion binding is a differential feature that may underlie the largely elusive biological function of OLF propellers.

It is shown that the 2p3d resonant inelastic X-ray scattering intensity is distorted by saturation and self-absorption effects, i.e. by incident-energy-dependent saturation and by emission-energy-dependent self-absorption.

An X-ray cross-correlation study of the impact of ligand composition and salt content on the self-assembly of soft-shell nanoparticles is presented, indicating symmetry-selective formation of order.

The Caddo people of Arkansas, Louisiana, Texas and Oklahoma have maintained many of their traditional ways and actively work to preserve their unique tribal cultural today. One example is the pottery of Jeri Redcorn.

The post Clay vessels by Native American potter Jeri Redcorn added to Smithsonian collections appeared first on Smithsonian Insider.

Recent work has added dozens of new measurements to star-forming regions in the Milky Way. These measurements have changed the map of the Milky Way, indicating our galaxy has four spiral arms, not two, as previously thought.

The post Very Large Baseline Array telescope is helping Smithsonian astronomers remap Milky Way and Andromeda galaxies appeared first on Smithsonian Insider.

A description and photos of the green-headed tanager (Tangara seledon), a bird native to east-central South America, can be found in the Species of the […]

The post Green-headed Tanager (Tangara seledon) of east-central South America appeared first on Smithsonian Insider.

Our studies of the genetic relationships between these bees tells us that they originated in the Amazon about 22 million years ago and that they moved north into Central America before 3 million years ago.

The post Two closely related bee species discovered far apart in Panama and northern Colombia appeared first on Smithsonian Insider.

Covered in venomous spines the exotic and strikingly banded Indo-Pacific lionfish would be a painful mouthful to any creature that may try to catch and […]

The post Biologist Andrew Sellers turns lionfish invasion into research opportunity appeared first on Smithsonian Insider.

Yes! When an animal trips a “camera trap” as a part of a project between the North Carolina Museum of Natural Sciences and the Smithsonian. […]

The post Can animals take a selfie? appeared first on Smithsonian Insider.

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 […]

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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.

Young athletes in the U.S. face a culture of resistance to reporting when they might have a concussion and to complying with treatment plans.

The Transportation Research Board’s Airport Cooperative Research Program (ACRP) recently selected winners for its University Design Competition for Addressing Airport Needs.

The National Academy of Medicine (NAM) and Robert Wood Johnson Foundation (RWJF) today named the 2018-2019 class of RWJF Health Policy Fellows.

The U.S. Coast Guard has safety regulatory oversight pertaining to vessel stability with standards that should respond to and improve with technological advances.

Rev. Heber Brown III wants people to erase the term “food desert” from their vocabulary.

Los Angeles City Attorney Mike Feuer, seen here in 2017, says his office has reached a settlement with a company that had been selling at-home tests for the coronavirus. The Food and Drug Administration says it has not authorized any at-home tests.; Credit: Christopher Weber/AP

Mike Feuer, the city attorney of Los Angeles, announced on Monday that his office had "filed a civil law enforcement action against, and achieved an immediate settlement with," a company that had been "illegally selling" an at-home test for the coronavirus.

The Food and Drug Administration has stated that the agency "has not authorized any test that is available to purchase for testing yourself at home for COVID-19."

But in March, Yikon Genomics Inc. offered a coronavirus test for sale online, claiming that the test could be performed "using a simple at-home finger stick blood sample." The company offered tests for $39 each and, in a since-deleted tweet, stated, "Our COVID-19 Test Kit is now FDA APPROVED!"

Yikon's "unlawful, unfair, and fraudulent business acts or practices," the LA city attorney alleged in the lawsuit against the company, "present a continuing threat to members of the public."

At a news conference, Feuer said that FDA validation of tests is crucial because an inaccurate result could lead someone infected with the coronavirus to "unknowingly expose others."

Under the settlement between Yikon and LA authorities, the company agreed to stop marketing or selling home test kits unless they receive FDA approval. Yikon also agreed to provide refunds to anyone who purchased its test kits, though Feuer said it's unclear how many tests were sold.

Yikon Genomics released a statement saying it "is committed to complying with all state & federal laws and regulations regarding the marketing & sale of medical devices. We intend to pursue FDA approval for the market & sale of COVID-19 test kits, which we hope will aid in mitigating this global health crisis."

The Trump administration has said it will "aggressively" prosecute cases of fraud related to the pandemic, and state attorneys general have also pledged to take legal action against scams around the country.

In LA, Feuer said his office continues to investigate other companies' sales of unapproved test kits.

"This is not an isolated incident," Feuer said, noting that his office separately sent a cease-and-desist letter to the California-based Wellness Matrix Group, which, as NPR first reported, had also been offering "at-home" test kits for sale.

"Whenever consumers are motivated in part by fears," the city attorney's office stated in its lawsuit against Yikon, "they are particularly vulnerable to fraudsters, scammers, and 'snake oil' hucksters and charlatans."

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

; Credit: /Janice Chang for NPR

The high school senior sitting across from Franciene Sabens was in tears over the abrupt amputation of her social life and turmoil at home. Because of the coronavirus, there will be no prom, no traditional send-off or ceremony for the graduates of Carbondale Community High School in Carbondale, Ill. And Sabens, one of the school's counselors, could not give the girl the one thing Sabens' gut told her the teen needed most.

"I want to hug them all, but I really wanted to hug that one," Sabens remembers.

Instead of a desk between counselor and student, there were miles of Internet cable and a computer screen. No hug. No private office. This is Sabens' new normal.

"Zoom is just not gonna ever bridge that gap," she says. "That one was pretty rough."

The job of the school counselor has evolved over the years, from academic guide to something deeper: the adult in a school tasked with fostering students' social and emotional growth, a mental health first responder and a confidant for kids, especially teens, who often need a closed door and a sympathetic ear. But the closure of nearly all U.S. schools has forced counselors like Sabens to reimagine how they can do their jobs. And the stakes have never been higher.

Why students need counselors now more than ever

Between closed schools, social isolation, food scarcity and parental unemployment, the coronavirus pandemic has so destabilized kids' support systems that the result, counselors say, is genuinely traumatic.

Sarah Kirk, an elementary school counselor in Tulsa, Okla., is especially worried about her students who were already at-risk, whose families "really struggle day to day in their homes with how they're going to pay the next bill and how they're going to get food on the table. Being home for this extended period of time is definitely a trauma for them."

For so many children, Kirk says, "school is their safe place. They look forward to coming. They don't want to leave when the day is over. And to take that away from them, I do worry about the traumatic experience that will cause for many of our students."

Counselors say part of the trauma comes from students being isolated from each other.

"In a middle school, that social piece is so important," says Laura Ross, a middle school counselor in Lawrenceville, Ga. Yes, they do a lot of connecting via social media, and that's still happening, "but that face-to-face and being with their friends... they're missing that."

Students are also experiencing a kind of grief "over what they've lost," Sabens says, especially seniors. "Losing out on the end of their senior years — something that they've dreamed about their whole life... has really been overwhelming for them. So there have been a lot of tears. There have been a lot of questions... 'What did we ever do to deserve this?'"

Unfortunately, there are no easy answers. Instead, Sabens says, she tries to let students know "that it's OK to not be OK. I mean, most of the world is not OK right now... It's OK to grieve about what you're losing because it is tragic."

Brian Coleman, a high school counselor in Chicago, says trauma is nothing new to many of his students, but he hopes awareness of the potentially traumatic effects of school closures means "trauma-informed care is going to really, really explode in ideally healthy, meaningful ways."

That means school leaders should right now be planning for the future, asking how they can best support students when they come back to school, Ross says, "making sure that we're prepared to deal with some of those feelings that are going to increase — of anxiousness, of grief, of that disconnect that they had for so long."

Broken connections

Not only are many students grieving and struggling with new trauma, it's also harder now for school counselors to help them. That's because counselors have lost one of the most powerful tools they had before schools closed: access. Before, counselors could speak to entire classrooms about bullying and how to manage their feelings, plus they enjoyed office space where students could drop in for a quick visit or schedule a tough conversation.

"I think about my eighth graders," says Laura Ross in Lawrenceville. "My office is in their hallway. I mean, they just stop by to say hello. They stop by when they're upset, just to come in and talk and, you know, figure out their feelings."

But all of that has changed. Today, a face-to-face video meeting is the closest a counselor can get to the old ideal. Before that can happen, though, Sabens says she has to find her students.

"Email, email, email, email — lots of emails," she says, calling it her "primary mode of communication with the students."

Connecting is even more complicated for elementary school counselors whose students generally don't have cell phones or email addresses. In Tulsa, Sarah Kirk says this inability to speak directly with children is "exactly what keeps me up at night."

So far, Kirk has mostly been in contact with parents and caregivers. "That's whose [phone] number I have... But it's really up to the parent if they want to hand the phone over [to the student]." She worries that, if a child is not OK at home and needs help, she won't know.

Kirk's focus on these calls has also shifted away from academics toward "the basic needs of our kids... making sure they have enough food. We're making sure they're safe."

Evelyn Ramirez, a first-year middle school counselor in rural Redwood Valley, Calif., agrees: "Our main priority right now is just to check the welfare of each student."

Ramirez, a first-generation Mexican-American, says online learning can put additional strain on immigrant and low-income families. "I feel for the students whose parents don't know English or don't really know how to help their students."

"It's no longer private"

NPR spoke with counselors across the country, from California to Georgia, Oklahoma to Ohio, and nearly all said they worry about even the best-case scenario — when they're able to connect with a student face-to-face using video chat technology. Their fear: privacy.

At school, "we have some sort of office space... where students can feel like they're having a private conversation with counselors," says Coleman in Chicago. "Now we're asking them to be vulnerable in some capacity at home. And for so many students, home is a space where they're triggered or they don't feel comfortable sharing ... because it's no longer private."

Yes, the student's bedroom door may be closed, says Ramirez in Redwood Valley, but "at any given point, someone can walk in or, you know, mom's down in the living room. She can probably hear [our] conversation." And that might keep students from really opening up about things like basic stress or even abuse.

The same holds true for many elementary school counselors.

"We do small group counseling for kids [who] are adjusting to a variety of changes, and there's an element of confidentiality that's built into that group," says Marie Weller, an elementary school counselor in Delaware, Ohio. "So I can't do a group online. I can't use Canvas or Zoom or Google Hangouts for a group because I can't get the confidentiality. So [I'm] trying to figure out, how can I check in?"

Getting creative

In Lawrenceville, Laura Ross admits: These have been trying times. But there's also a surprising upside, she says. The distance from students has forced her to get creative about how she uses technology to build a bridge back to them.

Before the outbreak, Ross helped create an after-school club for students who identify as LGBTQ+. When school closed, Ross set up a Google Classroom and asked if the club's members wanted to continue to meet virtually. "They definitely did. And the reactions were just a relief that they were still going to have the support of that club... the place that they could truly be themselves."

Ross says they even meet at the same time each week, just on Zoom.

On her last day in the office, before Ohio closed its schools, Marie Weller remembers starting to leave — then hesitating beside the childlike puppets she sometimes uses in her classroom counseling presentations. "Huh," she thought. "Maybe I'll be able to use these."

Weller and her fellow elementary school counselors say one important part of their job is making sure all students have the social-emotional skills and coping strategies they'll need to navigate a complex world. How can they do that now, from home?

Weller improvised.

She set up a smartphone camera in her house, surrounded by those puppets — a kind of surrogate classroom audience — and set about recording mini counseling lessons from her kitchen. Instead of the chime she normally uses to begin a lesson, she rings a mixing bowl with a red spatula. To teach kids about how and why they should filter what they say, leaving hurtful thoughts unspoken, she opens the coffee maker to show them how a real, paper filter works.

Weller does her own editing and even got permission from folk music favorites The Irish Rovers to use their song "What's Cooking In The Kitchen" as her opening theme. The resulting videos are brief, rich and charming, with lines like, "Your brain's amygdala acts like a guard dog."

And in Tulsa, Sarah Kirk is doing something similar, posting videos where she's sitting on the floor of her house, surrounded by colorful pennants and stuffed animals. Her dog, Crew, a cuddly 80-pound sheepadoodle (nearly as big as Kirk), even makes a camera-blocking cameo.

In her first episode, Kirk read a story meant to reassure children she can no longer hug. It's about how we all have an invisible string that connects us, even when we're far apart.

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

Patt Morrison models a headdress from the movie "The Lone Ranger."; Credit: Michelle Lanz/KPCC

Trust me – you’re going to be seeing a lot of these between now and Halloween.

I went to “The Lone Ranger” premiere last month, and outside the theater, Disneyland began selling a version of the Tonto headdress dreamed up by Johnny Depp and his folks for his role in the film, which I found to be a rollicking, ironic version of the classic action adventure with some very sober scenes evoking Native Americans’ tragic history.

The inspiration, Depp says, was artist Kirby Sattler’s interpretive 2006 painting “I Am Crow.”

Depp himself has claimed Native American ancestry, and the bird atop his bean plays a substantial if silent role in the proceedings. It is an interpretive painting, as I said, not a literal rendering of any tribal makeup. In the Sattler painting, the bird is flying above the figure’s head, not perched on it.

But the movie’s invested in storytelling, not the fine points of accuracy. If it had been, it wouldn’t have made the historical solecisms of relocating both Monument Valley and the transcontinental railroad to … Texas.

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

Selective fishing aims to prevent the overexploitation of target fish species and to protect by-catch species, but recent research has indicated that it could be having the opposite effect by damaging biodiversity and sustainability. An alternative approach called 'balanced exploitation' works at the level of the ecosystem instead of selectively removing specific components from the ecosystem.

New way to 'see' objects accelerates the future of self-driving cars

An image released by Google shows an early version of its driverless vehicle. The company has built several prototypes of the self-driving car.; Credit: /Google

California is one step closer this week to making the 1980s Hollywood fantasy of Knight Rider a 21st century reality because permits for self-driving cars issued by the Department of Motor Vehicles officially went into effect Tuesday. Now a handful of companies can test automated cars on public roads.

Buckle up — it's gonna be a wild ride.

John O'Dell is a Senior Editor at Edmunds.com, and he joins Alex Cohen to talk about what this means for the future of the driverless car industry.

 

New way to 'see' objects accelerates the future of self-driving cars

If left unpatched, a firmware flaw in some enterprise-class solid-state drives could make data on them unrecoverable as early as this fall

The post HPE issues fix to stop some SSDs from self‑destructing appeared first on WeLiveSecurity

Promoting the personal benefits of sustainable consumption, such as more free time and less stress, could play an important role in encouraging more sustainable living, according to a recent study. The researchers interviewed people who lived greener lifestyles and found that self-interest influenced their decision to consume less and buy sustainable products.

Campaigns which remind individuals of the environmentally-friendly actions they already perform may motivate them to even more pro-environmental behaviours, new research suggests. If people identify themselves as environmentally-friendly, they are more likely to carry out green actions, even in the absence of any incentive.

Excess nutrients in sea water can cause eutrophication, a major environmental concern. Shellfish species such as mussels can ‘soak up’ some of these nutrients. A recent Swedish study examines the cost-effectiveness of mussel farming in the Baltic Sea as a method of reducing nutrient concentration and compares its potential with other methods of combating eutrophication.

Recent research into the impact of different levels of noise on 75 volunteers reveals that disturbed sleep caused by night-time aircraft noise can damage blood vessels and increase the levels of stress hormones. As these physical changes are potential pathways to high blood pressure, heart and circulatory disease over the long term, reducing night-time aircraft noise is important for preventing cardiovascular disease in people living near airports.

A potential method for reducing greenhouse gas (GHG) emissions associated with extracting energy from oil shale has been highlighted by a recent study. A ‘self-fuelling’ method that recycles waste gas could cut GHGs emissions by 50% compared to the conventional oil shale product and 70% compared to crude oil.

Techniques for reducing the noise caused by wind turbines are reviewed in a new study. Noise pollution is one drawback of wind power and restricts where wind farms can be located in relation to people and wildlife. The researchers identify methods that could aid the design of low-noise wind turbines, including modifying the blade’s shape and adding rows of brushes to the edge of the blade.

Mussels exposed to high levels of microplastic pollution display signs of stress, new research has shown. However, levels of exposure were higher than found in the wild and no effect on the energy reserves of either mussels or lugworms was observed in the lab. tests. The researchers caution that longer experiments may be needed to reveal microplastics' full effects.

Automation failures have been the cause of such widely reported disasters as the crash of Air France Flight 447 in 2009, with most of the focus placed on deficiencies in the automated system. Although automation does help in avoiding human error in completing tasks, people are still needed to monitor how well the automated system is operating.

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Speed control, road traction, wipers when it rains, maintaining safe distances, collision avoidance, and lane change are some of the prominent features.

Auto Contact, our range of self-service solutions, can help free up agents to handle more complex and revenue-generating calls –and at the same time improve the overall customer experience whilst reducing costs.

A ‘feebate’ can be an effective policy option to aid the transition to a more environmentally-friendly transport system, a UK study suggests. This combination of fees and rebates can increase the take-up of low-carbon cars, the researchers argue, which leads to reduced life cycle greenhouse gas (GHG) emissions.