Three stars from Iowa women's basketball's 71-52 victory vs. Virginia Tech.

FSU women's basketball improves to 2-1 after a dominating victory over FAMU on Monday.

Evdokia Menelaou
Aug 8, 2012; 32:10925-10939
BehavioralSystemsCognitive

Yulia Lerner
Feb 23, 2011; 31:2906-2915
BehavioralSystemsCognitive

α-Neurexins are essential and highly expressed presynaptic cell-adhesion molecules that are frequently linked to neuropsychiatric and neurodevelopmental disorders. Despite their importance, how the elaborate extracellular sequences of α-neurexins contribute to synapse function is poorly understood. We recently characterized the presynaptic gain-of-function phenotype caused by a missense mutation in an evolutionarily conserved extracellular sequence of neurexin-3α (A687T) that we identified in a patient diagnosed with profound intellectual disability and epilepsy. The striking A687T gain-of-function mutation on neurexin-3α prompted us to systematically test using mutants whether the presynaptic gain-of-function phenotype is a consequence of the addition of side-chain bulk (i.e., A687V) or polar/hydrophilic properties (i.e., A687S). We used multidisciplinary approaches in mixed-sex primary hippocampal cultures to assess the impact of the neurexin-3α^A687 residue on synapse morphology, function and ligand binding. Unexpectedly, neither A687V nor A687S recapitulated the neurexin-3α A687T phenotype. Instead, distinct from A687T, molecular replacement with A687S significantly enhanced postsynaptic properties exclusively at excitatory synapses and selectively increased binding to neuroligin-1 and neuroligin-3 without changing binding to neuroligin-2 or LRRTM2. Importantly, we provide the first experimental evidence supporting the notion that the position A687 of neurexin-3α and the N-terminal sequences of neuroligins may contribute to the stability of α-neurexin–neuroligin-1 trans-synaptic interactions and that these interactions may specifically regulate the postsynaptic strength of excitatory synapses.

The GluN3A subunit of N-methyl-D-aspartate receptors (NMDARs) plays an established role in synapse development, but its contribution to neural circuits in the adult brain is less clear. Recent work has demonstrated that in select cell populations, GluN3A assembles with GluN1 to form GluN1/GluN3A receptors that are insensitive to glutamate and instead serve as functional excitatory glycine receptors (eGlyRs). Our understanding of these eGlyRs, and how they contribute to intrinsic excitability and synaptic communication within relevant networks of the developing and the mature brain, is only beginning to be uncovered. Here, using male and female mice, we demonstrate that GluN3A subunits are enriched in the adult ventral hippocampus (VH), where they localize to synaptic and extrasynaptic sites and can assemble as functional eGlyRs on CA1 pyramidal cells. GluN3A expression was barely detectable in the adult dorsal hippocampus (DH). We also observed a high GluN2B content in the adult VH, characterized by slow NMDAR current decay kinetics and a high sensitivity to the GluN2B-containing NMDAR antagonist ifenprodil. Interestingly, the GluN2B enrichment in the adult VH was dependent on GluN3A as GluN3A deletion accelerated NMDAR decay and reduced ifenprodil sensitivity in the VH, suggesting that GluN3A expression can regulate the balance of conventional NMDAR subunit composition at synaptic sites. Lastly, we found that GluN3A knock-out also enhanced both NMDAR-dependent calcium influx and NMDAR-dependent long-term potentiation in the VH. Together, these data reveal a novel role for GluN3A and eGlyRs in the control of ventral hippocampal circuits in the mature brain.

Neural decoding is a tool for understanding how activities from a population of neurons inside the brain relate to the outside world and for engineering applications such as brain–machine interfaces. However, neural decoding studies mainly focused on different decoding algorithms rather than different neuron types which could use different coding strategies. In this study, we used two-photon calcium imaging to assess three auditory spatial decoders (space map, opponent channel, and population pattern) in excitatory and inhibitory neurons in the dorsal inferior colliculus of male and female mice. Our findings revealed a clustering of excitatory neurons that prefer similar interaural level difference (ILD), the primary spatial cues in mice, while inhibitory neurons showed random local ILD organization. We found that inhibitory neurons displayed lower decoding variability under the opponent channel decoder, while excitatory neurons achieved higher decoding accuracy under the space map and population pattern decoders. Further analysis revealed that the inhibitory neurons’ preference for ILD off the midline and the excitatory neurons’ heterogeneous ILD tuning account for their decoding differences. Additionally, we discovered a sharper ILD tuning in the inhibitory neurons. Our computational model, linking this to increased presynaptic inhibitory inputs, was corroborated using monaural and binaural stimuli. Overall, this study provides experimental and computational insight into how excitatory and inhibitory neurons uniquely contribute to the coding of sound locations.

Harmonics are an integral part of music, speech, and vocalizations of animals. Since the rest of the auditory environment is primarily made up of nonharmonic sounds, the auditory system needs to perceptually separate the above two kinds of sounds. In mice, harmonics, generally with two-tone components (two-tone harmonic complexes, TTHCs), form an important component of vocal communication. Communication by pups during isolation from the mother and by adult males during courtship elicits typical behaviors in female mice—dams and adult courting females, respectively. Our study shows that the processing of TTHC is specialized in mice providing neural basis for perceptual differences between tones and TTHCs and also nonharmonic sounds. Investigation of responses in the primary auditory cortex (Au1) from in vivo extracellular recordings and two-photon Ca²⁺ imaging of excitatory and inhibitory neurons to TTHCs exhibit enhancement, suppression, or no-effect with respect to tones. Irrespective of neuron type, harmonic enhancement is maximized, and suppression is minimized when the fundamental frequencies (F₀) match the neuron's best fundamental frequency (BF₀). Sex-specific processing of TTHC is evident from differences in the distributions of neurons’ best frequency (BF) and best fundamental frequency (BF₀) in single units, differences in harmonic suppressed cases re-BF₀, independent of neuron types, and from pairwise noise correlations among excitatory and parvalbumin inhibitory interneurons. Furthermore, TTHCs elicit a higher response compared with two-tone nonharmonics in females, but not in males. Thus, our study shows specialized neural processing of TTHCs over tones and nonharmonics, highlighting local network specialization among different neuronal types.

Odor information arrives first in the main olfactory bulb and is then broadcasted to the olfactory cortices and striatum. Downstream regions have unique cellular and connectivity architectures that may generate different coding patterns to the same odors. To reveal region-specific response features, tuning and decoding of single-unit populations, we recorded responses to the same odors under the same conditions across regions, namely, the main olfactory bulb (MOB), the anterior olfactory nucleus (AON), the anterior piriform cortex (aPC), and the olfactory tubercle of the ventral striatum (OT), of awake male mice. We focused on chemically closely related aldehydes that still create distinct percepts. The MOB had the highest decoding accuracy for aldehydes and was the only region encoding chemical similarity. The MOB had the highest fraction of inhibited responses and narrowly tuned odor-excited responses in terms of timing and odor selectivity. Downstream, the interconnected AON and aPC differed in their response patterns to the same stimuli. While odor-excited responses dominated the AON, the aPC had a comparably high fraction of odor-inhibited responses. Both cortices share a main output target that is the MOB. This prompted us to test if the two regions convey also different net outputs. Aldehydes activated AON terminals in the MOB as a bulk signal but inhibited those from the aPC. The differential cortical projection responses generalized to complex odors. In summary, olfactory regions reveal specialized features in their encoding with AON and aPC differing in their local computations, thereby generating inverse net centrifugal and intercortical outputs.

Hyperbilirubinemia (HB) is a key risk factor for hearing loss in neonates, particularly premature infants. Here, we report that bilirubin (BIL)-dependent cell death in the auditory brainstem of neonatal mice of both sexes is significantly attenuated by ZD7288, a blocker for hyperpolarization-activated cyclic nucleotide-gated (HCN) channel-mediated current (I_h), or by genetic deletion of HCN1. GABAergic inhibitory interneurons predominantly express HCN1, on which BIL selectively acts to increase their intrinsic excitability and mortality by enhancing HCN1 activity and Ca²⁺-dependent membrane targeting. Chronic BIL elevation in neonatal mice in vivo increases the fraction of spontaneously active interneurons and their firing frequency, I_h, and death, compromising audition at the young adult stage in HCN1^+/+, but not in HCN1^–/– genotype. We conclude that HB preferentially targets HCN1 to injure inhibitory interneurons, fueling a feedforward loop in which lessening inhibition cascades hyperexcitability, Ca²⁺ overload, neuronal death, and auditory impairments. These findings rationalize HCN1 as a potential target for managing HB encephalopathy.

Impaired inhibitory synapse development is suggested to drive neuronal hyperactivity in autism spectrum disorders (ASD) and epilepsy. We propose a novel mechanism by which astrocytes control the development of parvalbumin (PV)-specific inhibitory synapses in the hippocampus, implicating ephrin-B/EphB signaling. Here, we utilize genetic approaches to assess functional and structural connectivity between PV and pyramidal cells (PCs) through whole-cell patch–clamp electrophysiology, optogenetics, immunohistochemical analysis, and behaviors in male and female mice. While inhibitory synapse development is adversely affected by PV-specific expression of EphB2, a strong candidate ASD risk gene, astrocytic ephrin-B1 facilitates PV->PC connectivity through a mechanism involving EphB signaling in PV boutons. In contrast, the loss of astrocytic ephrin-B1 reduces PV->PC connectivity and inhibition, resulting in increased seizure susceptibility and an ASD-like phenotype. Our findings underscore the crucial role of astrocytes in regulating inhibitory circuit development and discover a new role of EphB2 receptors in PV-specific inhibitory synapse development.

Experience- and activity-dependent transcription is a candidate mechanism to mediate development and refinement of specific cortical circuits. Here, we demonstrate that the activity-dependent transcription factor myocyte enhancer factor 2C (MEF2C) is required in both presynaptic layer (L) 4 and postsynaptic L2/3 mouse (male and female) somatosensory (S1) cortical neurons for development of this specific synaptic connection. While postsynaptic deletion of Mef2c weakens L4 synaptic inputs, it has no effect on inputs from local L2/3, contralateral S1, or the ipsilateral frontal/motor cortex. Similarly, homozygous or heterozygous deletion of Mef2c in presynaptic L4 neurons weakens L4 to L2/3 excitatory synaptic inputs by decreasing presynaptic release probability. Postsynaptic MEF2C is specifically required during an early postnatal, experience-dependent, period for L4 to L2/3 synapse function, and expression of transcriptionally active MEF2C (MEF2C-VP16) rescues weak L4 to L2/3 synaptic strength in sensory-deprived mice. Together, these results suggest that experience- and/or activity-dependent transcriptional activation of MEF2C promotes development of L4 to L2/3 synapses. Additionally, MEF2C regulates the expression of many pre- and postsynaptic genes in postnatal cortical neurons. Interestingly, MEF2C was necessary for activity-dependent expression of many presynaptic genes, including those that function in transsynaptic adhesion and neurotransmitter release. This work provides mechanistic insight into the experience-dependent development of specific cortical circuits.

Seven guest collaborators bring new eyes to a Smithsonian museum founder’s collection of American art

A recent exhibition shows how soldiers sent in votes during the Civil War and World War II, as many Americans would in 2020 following the spread of the Covid-19 pandemic

A paleontologist at the Natural History Museum in London chronicles the age of the famous and fascinating massive reptiles

The work, now on view at the Smithsonian American Art Museum, tells the story of two characters on the island—the last people alive in the world

The firebrand politician once quipped that she would like to be remembered as a woman who ‘had guts’

From This Object in History, aired on @SmithsonianChannel

Chris Mah, researcher at the Smithsonian Institution's National Museum of Natural History in the invertebrate zoology department, describes the characteristics of different sea star species observed on the final dive of the Laulima O Ka Moana expedition. (Credit: Video courtesy of the NOAA Office of Ocean Exploration and Research, 2017 Laulima O Ka Moana)

Discover evidence of natural selection and evolution at the Smithsonian's Natural History Museum (Meredith Bragg)

Watch a course video excerpt from Rise of the Superheroes: The legendary Stan Lee, creator of the Avengers, Spiderman and Iron Man, has partnered with the Smithsonian National Museum of American History to launch the first global online course about superheroes to fans around the world.

A step-by-step tour of the renovation of the National Museum of American History (Narration by Beth Py-Lieberman / Edited by Ryan Reed and Brian Wolly)

A museum in Portland, Oregon highlights the multi-layered path of 3D imagery, from stereoscopes of the American West to blockbuster movies

Smithsonian's own jazz man, John Edward Hasse, gives a lesson on the influential music genre. Read more at: https://www.smithsonianmag.com/arts-culture/the-smithsonians-ambassador-of-jazz-53620539/

What fueled the frenzy that sent so many to their deaths in colonial America? And how did Americans reckon with the aftermath of the panic? --- For more videos from Smithsonian Magazine: https://www.smithsonianmag.com/videos/ Digital Editorial Director: Brian Wolly Supervising Producer & Scriptwriter: Michelle Mehrtens Video Editor: Sierra Theobald

Uncover the bittersweet story of this ancient treat. Read more at https://www.smithsonianmag.com/arts-culture/a-brief-history-of-chocolate-21860917/

Have you ever wondered whether lie detectors actually...work? Join us as we delve into the history and science behind these devices - from how they measure "deception" to the controversies surrounding their use. This video is the first episode of the National Treasure series, where we share behind-the-scenes stories of objects in the Smithsonian Collections. --------- To learn more about the exhibition "Forensic Science on Trial" at Smithsonian's National Museum of American History, read below: What a 100-Year-Old Lie Detector and 150-Year-Old Arsenic Tests Tell Us About Forensic Science Today https://www.smithsonianmag.com/smithsonian-institution/what-a-100-year-old-lie-detector-and-150-year-old-arsenic-tests-tell-us-about-forensic-science-today-180984623/ Forensic Science on Trial https://americanhistory.si.edu/explore/exhibitions/forensic-science-trial Digital Editorial Director: Brian Wolly Supervising Producer & Scriptwriter: Michelle Mehrtens Producer: Nicki Marko Producer & Editor: Sierra Theobald Motion Designer: Ricardo Jaimes Original Footage: Cade Martin

What caused the Plague? And what methods did people use to combat the spread? Learn about its origins, past outbreaks (including the Black Death), and the long-lasting impact of its legacy today. --- For more videos from Smithsonian Magazine: https://www.smithsonianmag.com/videos/ Digital Editorial Director: Brian Wolly Supervising Producer & Scriptwriter: Michelle Mehrtens Producer: Nicki Marko Producer: Sierra Theobald Video Editor: Natalie Cline Graphic Designer: Kevin Schoenblum

With his bright red coat, big orange nose, and wide eyes, Elmo is arguably the most famous of the Sesame Street muppets–but he didn’t always have it this good. Elmo began as an "Anything Muppet"—an extra, if you will, until Kevin Clash refashioned his character into the one we know—and kids love–today. Throughout the '80s his star continued to shine, eventually becoming an international icon and best-selling Christmas toy. Forty years later, he’s still going strong, enshrined in a popular exhibit at the Smithsonian’s National Museum of American History.

Book-banning might seem like a relic of less enlightened times, but the practice is back in a big way. The American Library Association reports (https://www.smithsonianmag.com/smart-news/american-library-association-names-2022s-most-banned-books-180982048/) that 2022 saw more attempts to have books removed from public libraries than in any prior year this century — indeed, it documented more than twice as many attempted bans in 2022 than in 2021. In schools, attempts to keep certain books out of the hands of students have been even more aggressive and draconian. What’s new about these efforts is the subject that binds the most-challenged titles: Most of them address themes of LGBT+ identity or gender expression. In this episode, we talk with journalist Colleen Connolly about Thomas Morton’s New English Canaan, the first book ever to be suppressed in North America. What did the Puritans find so threatening about it, and how has this book echoed through subsequent centuries? Then we’re joined by Dr. Carla Hayden, Librarian of Congress, for a wide-ranging conversation about the history of book bans in the United States, how a resurgent wave of book bans in many states differs from those of prior eras, and why organized attempts to prevent specific people from reading specific books usually fail. A transcript of this episode can be found here (http://smithsonianmag.com/history/a-brief-history-of-banned-books-in-america-180983011) . Read Colleen’s Smithsonian story about New English Canaan here (https://www.smithsonianmag.com/history/how-americas-first-banned-book-survived-and-became-an-anti-authoritarian-icon-180982971/) . Find prior episodes of our show here (https://www.smithsonianmag.com/podcast/) . There’s More to That is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is Chris Klimek, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Adriana Rosas Rivera, Genevieve Sponsler, Terence Bernardo, and Edwin Ochoa. The Executive Producer of PRX Productions is Jocelyn Gonzales. Fact-checking by Stephanie Abramson. Episode artwork by Emily Lankiewicz. Music by APM Music.

Edwin Bearss lends a dynamic personality and a booming voice to teaching the history of the Civil War in northern Virginia (Meredith Bragg)

The facts of Sojourner Truth’s life are inspiring: Born into slavery in the late 1790s, she became an influential abolitionist and Pentecostal preacher, transfixing audiences from the mid 1840s through the late 1870s with her candid and powerful voice, not to mention her singing. Tall and strong, Truth was physically formidable, too. No one was using the term “intersectionality” in the 19th century, but Truth embodied this idea, declaring that her Blackness and her womanhood were equally essential facets of her identity. But many people, both in Truth’s lifetime and in the approximately 140 years since her death, have found it useful to recast Truth as they wish to remember her instead of as she was. There’s no better example of this than “Ain’t I a woman?,” the hypothetical that Truth supposedly put to the audience when she addressed a women’s rights convention in 1851 in Akron, Ohio—the city where a public plaza will be dedicated in her honor this spring. There’s reason to doubt she said that, or at least that she said it in that way. In this episode, we speak with two historians who’ve dug into Truth’s complicated legacy and challenged much of what’s been written about this American icon. Cynthia Greenlee reported on recent efforts to honor Truth (https://www.smithsonianmag.com/history/remarkable-untold-story-sojourner-truth-180983691/) for the March 2024 issue of Smithsonian. Nell Irvin Painter wrote the groundbreaking 1996 biography Sojourner Truth: A Life, A Symbol, and she’s hard at work on a follow-up volume titled Sojourner Truth Was a New Yorker and She Didn’t Say That. Together, Greenlee and Painter help us understand us who Sojourner Truth really was, and why several generations of activists have claimed her as a symbol — at the expense of our understanding of her as a person. Read Cynthia Greenlee’s March 2024 Smithsonian story about Sojourner Truth here (https://www.smithsonianmag.com/history/remarkable-untold-story-sojourner-truth-180983691/) . You can learn more about Dr. Greenlee and her work at her site (https://www.cynthiagreenlee.com/) . You can learn more about Dr. Nell Irvin Painter’s work as an author, artist, and historian at her site (http://www.nellpainter.com/) . And read more here for the history of Mar-a-Lago (https://www.smithsonianmag.com/history/history-mar-a-lago-180965214/) mentioned in our dinner party fact. Find prior episodes of our show here (https://www.smithsonianmag.com/podcast/) . There’s More to That is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is Chris Klimek, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Adriana Rosas Rivera, Genevieve Sponsler, Rye Dorsey, and Edwin Ochoa. The Executive Producer of PRX Productions is Jocelyn Gonzales. Fact-checking by Stephanie Abramson. Episode artwork by Emily Lankiewicz. Music by APM Music.

He is (K)enough… or is he? With filmmaker Greta Gerwig's Barbie breaking box-office records—and devoting much of its story to Ken's existential crisis—we wondered if there's any more to Barbie's perennial plus-one. Journalist and lifelong Barbie fan Emily Tamkin talks us through Ken’s development, or lack thereof, over the decades. Read Emily’s “A Cultural History of Barbie,” and Chris’s brief Ken history “Not Your Average Beau,” here (https://www.smithsonianmag.com/arts-culture/cultural-history-barbie-180982115/) or in the June 2023 issue of Smithsonian. Emily is the author of The Influence of Soros: Politics, Power, and the Struggle for an Open Society and Bad Jews: A History of American Jewish Politics and Identities. Learn more about Emily and her work here (https://www.emilytamkin.com/) , or subscribe to her Substack newsletter (https://emilyctamkin.substack.com/) . There’s More to That is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is Chris Klimek, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Genevieve Sponsler, Adriana Rozas Rivera, Terence Bernardo, and Edwin Ochoa. The Executive Producer of PRX Productions is Jocelyn Gonzales. Episode artwork by Emily Lankiewicz. Music by APM Music.

From the Americas to Europe then back again, there's more to the potato than meets the eyes.

Four decades ago, Pablo Escobar brought to his Medellín hideaway four hippopotamuses, the centerpieces of a menagerie that included llamas, cheetahs, lions, tigers, ostriches and other exotic fauna. After Colombian police shot Escobar dead in December 1993, veterinarians removed the animals—except the hippos, which were deemed too dangerous to approach. The hippos fled to the nearby Magdalena River and multiplied.  Today, the descendants of Escobar’s hippos are believed to number nearly 200. Their uncontrolled growth threatens the region’s fragile waterways. Smithsonian contributor Joshua Hammer joins us to recount this strange history and explain why Colombian conservationists have embarked upon an unusual program to sterilize these hippos in the wild via “invasive surgical castration,” a procedure that is, as he has written (https://www.smithsonianmag.com/science-nature/pablo-escobar-abandoned-hippos-wreaking-havoc-colombian-jungle-180984494/) for Smithsonian magazine, “medically complicated, expensive and sometimes dangerous for hippos as well as for the people performing it.” Then, ecologist Rebecca Lewison tells us how her long-term study of hippo populations in Africa offers hints of how these creatures will continue to alter the Colombian ecosystem—and what authorities can do about it. Let us know what you think of our show, and how we can make it better, by completing our There's More to That listener survey here (https://docs.google.com/forms/d/e/1FAIpQLSfS90zjBZ2oGa9JxVa-R5affKcOHaR2-ib1_KZeWm3HDQXJIA/viewform) . Read Josh Hammer's Smithsonian story about Escobar's hippos and their descendants here (https://www.smithsonianmag.com/science-nature/pablo-escobar-abandoned-hippos-wreaking-havoc-colombian-jungle-180984494/) . Learn more about Rebecca Lewison and her work here (https://cmi.sdsu.edu/rebecca-lewison/) . Find prior episodes of our show here (https://www.smithsonianmag.com/podcast/) . There’s More to That is a production of Smithsonian magazine and PRX Productions. From the magazine, our team is Chris Klimek, Debra Rosenberg and Brian Wolly. From PRX, our team is Jessica Miller, Adriana Rosas Rivera, Genevieve Sponsler, Rye Dorsey, and Edwin Ochoa. The Executive Producer of PRX Productions is Jocelyn Gonzales. Fact-checking by Stephanie Abramson. Episode artwork by Emily Lankiewicz  Music by APM Music.

More on 3D scanning: http://j.mp/JM43KD Specialists are using new technology to unravel a mystery in the Smithsonian collections.

Merry "Corky" White, author of Coffee Life in Japan, traces the history of coffee culture in the United States

Listen to a short lecture given by curator Margaret Weitekamp on Gene Kranz career with NASA and how his vest ended up at the Smithsonian

The American Ingenuity Award winner is using geographic information systems to map history's most iconic landscapes

Curator Larry Bird takes you inside the history of the Bradford dollhouse

In the spring of 1961, black and white civil rights activists rode buses to protest the segregationist policies of the Deep South (Marian Holmes, Brian Wolly, Photos courtesy of Corbis, Getty Images and Library of Congress, Audio clips courtesy of Smithsonian Folkways. Read more at https://www.smithsonianmag.com/history/the-freedom-riders-then-and-now-45351758/

Clues into the disappearance of the ancient Picts lie in the tiny Scottish village of Aberlemno: 1,700-year-old Pictish stones, marked with some very unusual carvings.

The Kyoto museum will feature interactive exhibits, gaming artifacts, workshop spaces and oversized controllers inspired by iconic video games

History forgot about "Gibbet Hill" for more than a century—until a fan of the Gothic horror writer stumbled upon the haunting tale at the National Library of Ireland

The public tours of the historic residence hadn't been overhauled in decades. For two years, the first lady's office has been working to make them more interactive and educational

Antonia, a cloned black-footed ferret at the Smithsonian's National Zoo and Conservation Biology Institute, has produced two healthy offspring that will help build genetic diversity in their recovering population

The actress becomes the first wheelchair user ever to take home the coveted prize at the 73rd annual award show

Pedestrians in Montreal, Grand Rapids and other locations can time-travel thanks to installations that map historical scenes directly onto the cityscapes