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You can now flag issues in the Montreal Metro system by text

The Société de transport de Montréal (STM) has established a non-urgent text line for transit users to signal security issues in the Metro network.



  • News/Canada/Montreal

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Man, 36, charged with 1st-degree murder of partner on Montreal's South Shore

Shilei Du, 36, was charged Monday morning with the premeditated murder of his partner, Guangmei Ye, whose body was found Sunday in a residence on Fontenelle Street in Candiac, Que.



  • News/Canada/Montreal

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Veterans honoured at Remembrance Day ceremonies across Quebec



  • News/Canada/Montreal

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Video game shines light on Indigenous history and voices

Two Falls (Nishu Takuatshina) was developed in Montreal by a local studio that collaborated closely with Indigenous designers and consultants.




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Montreal neighbourhood rallies around cafe after co-owner’s sudden death

Loved ones, friends, and people from across the city have all come together to support each other at Pastel Rita, the café Jocelyn Després helped so many call home.




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Montreal says it's making it easier for groups to build off-market housing

The City of Montreal wants to sell more land to community organizations, housing co-ops and other groups to build off-market housing. 



  • News/Canada/Montreal

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Music still a ‘passion,’ not a job for Montreal funk band The Brooks as they drop 5th album

Ten years after their formation, the members of The Brooks discuss how they’ve evolved and how they view their collaboration.




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Labour minister forcing end of negotiations at Quebec ports marks 'dark day for workers' rights,' union says

The union representing dockworkers in Montreal says Canada's labour minister forcing its members back to work at ports in Montreal and Quebec City marks a "dark day for workers' rights."



  • News/Canada/Montreal

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Body found in Montreal nature park was that of kidnapped cryptocurrency influencer, police say

Quebec provincial police have confirmed that the body found in a Montreal nature park on Oct. 30 was that of kidnapping victim and cryptocurrency influencer Kevin Mirshahi.



  • News/Canada/Montreal

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Dextran Amine-Conjugated Neural Tracing in Mosquitoes

To understand the circuitry of the brain, it is often advantageous to visualize the processes of a single neuron or population of neurons. Identifying sites where a neuron, or neurons, originates and where it projects can allow a researcher to begin to map the circuitry underlying various processes, including sensory-guided behaviors. Furthermore, neural tracing allows one to map locations where processes terminate onto regions of the brain that may have known functions and sometimes to identify candidate upstream or downstream connections, based on proximity. Many methods of neural tracing are available; here, we focus on loading fluorescent dyes into a neuron (fluorescent dye filling). Different options for dyes exist to label neurites. Among the most versatile and easy to use are dextran amine–conjugated dyes. They fill neurons bidirectionally, not discriminating between anterograde or retrograde loading direction. Dye filling must be done in unfixed tissue, as the dye needs to move through the neurons; however, dextran amine conjugates are aldehyde-fixable and once cells have been fully loaded with dye the tissue can be fixed and subjected to immunostaining. Coupling neural tracing with immunofluorescence is a useful way to determine specific brain or ventral nerve cord (VNC) regions where a neuron projects. This protocol describes methods for loading dextran amine conjugated dyes into a sensory tissue in the mosquito to visualize sites of sensory neuron innervation in the central nervous system, as well as efferent projections to these structures. This protocol is described for Aedes aegypti, for which it was optimized, but it also works across a variety of insects.




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Ventral Nerve Cord Dissection and Microscopy of Drosophila Embryos

The technique of visualizing axon pathways in the embryonic ventral nerve cord using antibody labeling has been fundamental to our understanding of the genetic and developmental mechanisms underlying nervous system wiring in Drosophila. High-resolution microscopic examination of the ventral nerve cord remains an essential component of many experiments in Drosophila developmental neuroscience. Although it is possible to examine the ventral nerve cord in intact whole-mount embryos, to collect the highest-quality images it is often useful to isolate the nervous system away from the other embryonic tissues through embryo dissection. This protocol describes methods for dissecting ventral nerve cords from Drosophila embryos that have been fixed and stained via immunofluorescence or horseradish peroxidase (HRP) immunohistochemistry. The process of making fine dissection needles for this purpose from electrolytically sharpened tungsten wire is also described. Dissected and mounted ventral nerve cords can be examined and imaged using a variety of microscopy techniques including differential interference contrast (DIC) optics, epifluorescence, or confocal microscopy.




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Collection, Fixation, and Antibody Staining of Drosophila Embryos

The Drosophila embryonic central nervous system has been used for decades as a model for understanding the genetic regulation of axon guidance and other aspects of neural development. Foundational studies using antibody staining to examine the embryonic ventral nerve cord in wild-type and mutant animals led to the discovery of evolutionarily conserved genes that regulate fundamental aspects of axon guidance, including midline crossing of axons. The development of the regular, segmentally repeating structure of axon pathways in the ventral nerve cord can illustrate basic principles of axon guidance to beginning students and can also be used by expert researchers to characterize new mutants, detect genetic interactions between known genes, and precisely quantify variations in gene function in engineered mutant lines. Here, we describe a protocol for collecting and fixing Drosophila embryos and visualizing axon pathways in the embryonic ventral nerve cord using immunofluorescence or immunohistochemical staining methods. As embryogenesis in Drosophila takes ~24 h to complete, a 1-d collection yields embryos representing all stages of development from newly fertilized through ready-to-hatch larvae, allowing investigation of multiple developmental events within a single batch of collected embryos. The methods described in this protocol should be accessible to introductory laboratory courses as well as seasoned investigators in established research laboratories.




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Amplification and Identification of Vertebrate Host Cytochrome c Oxidase Subunit I (COI) DNA Barcoding Templates from Mosquito Blood Meals

Mosquitoes take blood meals from a diverse range of host animals and their host associations vary by species. Characterizing these associations is an important element of the transmission dynamics of mosquito-vectored pathogens. To characterize mosquito host associations, various molecular techniques have been developed, which are collectively referred to as blood meal analysis. DNA barcoding has diverse biological applications and is well-suited to mosquito blood meal analysis. The standard DNA barcoding marker for animals is a 5' fragment of the cytochrome c oxidase I (COI) gene. A major advantage of this marker is its taxonomic coverage in DNA sequence reference databases, making it feasible to identify a wider range of mosquito host species than with any other gene. However, the COI gene contains high sequence variation at potential priming sites between vertebrate orders. Coupled with the need for primer sequences to be mismatched with mosquito priming sites so that annealing to mosquito DNA is inhibited, it can be difficult to design primers suitable for blood meal analysis applications. Several primers are available that perform well in mosquito blood meal analysis, annealing to priming sites for most vertebrate host taxa, but not to those of mosquitoes. Because priming site sequence variation among vertebrate taxa can cause amplification to fail, a hierarchical approach to DNA barcoding-based blood meal analysis can be applied. In such an approach, no single primer set is expected to be effective for 100% of potential host species. If amplification fails in the initial reaction, a subsequent reaction is attempted with primers that anneal to different priming sites, and so on, until amplification is successful.




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Preservation of Field-Collected Mosquito Blood Meals

All PCR- and DNA-based blood meal analyses require host DNA from a mosquito blood meal to be effectively preserved between the time when the specimen is collected and the extraction of DNA. As soon as a mosquito ingests blood from a host animal, digestion of host cells and cellular components within the blood meal by enzymes in the mosquito midgut begins to degrade the host DNA templates that are the targets of polymerase chain reaction (PCR) amplification. Without effective preservation, host DNA is typically undetectable by PCR 48 h after feeding, because of digestion. Preservation methods for mosquito blood meals vary in their efficacy, and the logistics of fieldwork can limit the options for preservation of blood meals and maintenance of the integrity of host DNA. This protocol describes a method of blood meal preservation that is effective, convenient, and amenable to fieldwork in remote locations where cryopreservation at –20°C or –80°C may not be feasible. It uses a Flinders Technology Associates (FTA) card, which is a chemically treated card that lyses cells and allows nucleic acids to be preserved. This method is also expected to preserve the DNA or RNA of pathogens present within the engorged mosquito abdomen, including RNA viruses.




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Identification of Mosquito Eggshell Proteins from Aedes aegypti by Liquid Chromatography with Tandem Mass Spectrometry (LC-MS/MS) Proteomic Analysis

The insect eggshell is a multifunctional structure with several important roles, including generating an entry point for sperm via the micropyle before oviposition, serving as an oviposition substrate attachment surface, and functioning as a protective layer during embryo development. Eggshell proteins play major roles in eggshell tanning and hardening following oviposition and provide molecular cues that define dorsal–ventral axis formation. Precise eggshell formation during ovarian follicle maturation is critical for normal embryo development and the synthesis of a defective eggshell often gives rise to inviable embryos. Therefore, simple and accurate methods for identifying eggshell proteins will facilitate our understanding of the molecular pathways regulating eggshell formation and the mechanisms underlying normal embryo development. This protocol describes how to isolate and enrich eggshells from mature oocytes of Aedes aegypti mosquitoes and how to extract their eggshell proteins for liquid chromatography with tandem mass spectrometry (LC–MS/MS) proteomic analysis. Although this methodology was developed for studying mosquito eggshells, it may be applicable to eggs from a variety of insects. Mosquitoes are ideal model organisms for this study as their ovarian follicle development and eggshell formation are meticulously regulated by blood feeding and their follicles develop synchronously throughout oogenesis in a time-dependent manner.




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Visualization of Apoptotic Ovarian Follicles during Aedes aegypti Mosquito Egg Maturation by Fluorescent Imaging Studies

In insects, oocyte resorption (oosorption) or follicular atresia is one of the key physiological processes and evolutionary strategies used to optimize reproductive fitness. Mosquitoes are ideal model organisms for studying egg maturation in arthropods, as their follicle development is initiated only following the ingestion of a blood meal, followed by a carefully orchestrated series of hormonally regulated events leading to egg maturation. A cohort of approximately 100 follicles per mosquito ovary begin developing synchronously. However, a significant fraction of follicles ultimately undergo apoptosis and oosorption, especially when available resources from the blood meal are limited. Therefore, simple, rapid, and reliable techniques to accurately evaluate follicular atresia are necessary to understand mechanisms underlying follicle development in insects. This protocol describes how to detect apoptotic follicle cells within the Aedes aegypti mosquito ovaries using a commercially available fluorescent-labeled inhibitor of caspases (FLICA). Caspases are key players in animal apoptosis. In this assay, the FLICA reagent enters the intracellular compartment of follicles in dissected mosquito ovaries and covalently binds to active caspases. The bound reagent remains within the cell and its fluorescent signal can be observed by confocal microscopy. Although this method was specifically developed for visualizing apoptotic ovarian follicles during Ae. aegypti mosquito egg development, it should be applicable to other mosquito tissues that undergo caspase-mediated program cell death in a time-dependent manner.




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Generating and Validating Transgenic Mosquitoes with Transposon-Mediated Transgenesis

Transposon-mediated transgenesis has revolutionized both basic and applied studies of mosquito vectors of disease. Currently, techniques such as enhancer traps and transposon tagging, which rely on remobilizable insertional mutagenesis, are only possible with transposon-based vector systems. Here, we provide general descriptions of methods and applications of transposon-based mosquito transgenesis. The exact procedures must be adapted to each mosquito species and comparisons of some differences among different mosquito species are outlined. A number of excellent publications showing detailed and specific protocols and methods are featured and referenced.




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The Smithsonian Gets Experimental and Field-Tests a New Forum for Bringing Artists to the Public

A Two-Day Festival in the historic Arts & Industries Building brings community, artists and scholars together for a “Culture Lab”




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Podcast: On the Way to Peak Phosphorus

On this episode of Generation Anthropocene, we dive into one of the most underappreciated elements on the periodic table




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The Student and the Spy: How One Man’s Life Was Changed by the Cambridge Five

An unlikely friendship with Guy Burgess, the infamous British double-agent, brought unexpected joy to Stanley Weiss




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The Real Science Behind the Megalodon

As The Meg hits theaters, dive into what we really know about this chompy predator




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Europe’s Megalithic Monuments Originated in France and Spread by Sea Routes, New Study Suggests

The ancient burial structures, strikingly similar all across Europe and the mediterranean, have puzzled scientists and historians for centuries




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Museum Director Discovers His Mother’s Childhood Visit to the Smithsonian

By raising her son to be curious about the natural world, this mother helped shape the trajectory of the National Museum of Natural History




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Power corporation relying less on diesel in the N.W.T.'s North Slave this year

The Northwest Territories Power Corporation expects that by the end of March it will have generated 72 per cent of power for the North Slave region using hydro, and 28 per cent from diesel. Last year, about half the region's power was from diesel because of low water levels.



  • News/Canada/North

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Former mayor accused of property encroachment violations in Dawson City files his defence against town

Former Dawson City Mayor Bill Kendrick has filed his defence against the town's encroachment violation lawsuit.



  • News/Canada/North

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104-year-old Yukon woman looks back on life and love in wartime

Wanita Johnson, who celebrates her birthday this weekend in Whitehorse, still has a sharp memory for how the Second World War helped shape her life.



  • News/Canada/North

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A creek near the Eagle Gold mine in Yukon sees mercury levels spike

Water quality guidelines for mercury are 0.02 micrograms per litre of water. Several results show that levels at four sites are far above that threshold. During the second week of October, one value close to the mine was more than seven times the acceptable level.



  • News/Canada/North

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'I knew I was gonna die': Yukon paraglider recounts terrifying, high-altitude mishap in India

Paraglider Ben Lewis remembers spinning around wildly as he got pulled up higher and higher into the violent storm. That was when he realized, about 6,700 metres up in the sky and still rising, that he was not likely to see his family again.



  • News/Canada/North

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This Yellowknife woman biked 1,000 kilometres along WW1's front lines

Stephanie Yuill spent five weeks visiting First World War sites across Europe on a bike she bought from the grocery store. 



  • News/Canada/North

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Homeowner charged in connection with deadly house explosion in Whitehorse a year ago

A Whitehorse homeowner has been charged in connection with an explosion last year that destroyed his home and killed a man in a neighbouring house. 



  • News/Canada/North

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Residents across river from Dawson City, Yukon, stepping up to help neighbours when emergency services limited

A group of volunteers have been providing emergency services to West Dawson residents during the periods of freeze up and break up, when there is no reliable access across the Yukon River to town.



  • News/Canada/North

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Fleeing police, man out on bail drives on walking trail, breaks into Yellowknife home

A man who fled from police, drove onto a walking trail, triggered a shelter-in-place advisory for the Chateau Nova hotel in Yellowknife and subsequently broke into a home was on bail at the time and under house arrest, police say.



  • News/Canada/North

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This Female Civil War Soldier Participated in the Bloodiest Battle in American History and Spied on the South—or Did She?

Historians say that Sarah Emma Edmonds exaggerated many aspects of her wartime experiences. Still, she bravely served in the Union Army, becoming one of hundreds of women who fought in the conflict in secret




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This Defeated Presidential Candidate, Once the 'Best-Known Man in America,' Died in a Sanatorium Less Than a Month After Losing the Election

Newspaper editor Horace Greeley unsuccessfully ran against incumbent Ulysses S. Grant in November 1872. Twenty-four days later, he died of unknown causes at a private mental health facility




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Inside Disney's Controversial Plan to Open a Theme Park Inspired by American History

In the early 1990s, historians and the public alike questioned how Disney's America would accurately and sensitively document the nation's thorny past




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The Real Story Behind 'Saturday Night,' the Movie About the Television Show That Changed Comedy Forever

A new film revisits the 90 minutes before the first episode of "Saturday Night Live" premiered on NBC on October 11, 1975




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How a Dead Seal Sparked Theodore Roosevelt's Lifelong Passion for Conservation

As a child, the future president acquired a marine animal's skull, which became the first specimen in his natural history collection




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Back in the 19th Century, Your Election Ballot Could Double as a Work of Art

During and after the Civil War, inventive illustrations allowed Democrats and Republicans to turn American ballots into powerful propaganda




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How Recovering the History of a Little-Known Lakota Massacre Could Heal Generational Pain

When the U.S. Army massacred a Lakota village at Blue Water, dozens of plundered artifacts ended up in the Smithsonian. The unraveling of this long-buried atrocity is forging a path toward reconciliation




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The Enterprising Woman Who Built—and Lost, and Rebuilt—a Booming Empire During the Klondike Gold Rush

With flinty perseverance and a golden touch, Belinda Mulrooney earned an unlikely fortune in the frozen north and reshaped the Canadian frontier




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When the Nazis Seized Power, This Jewish Actor Took on the Role of His Life

After he was forced off the German stage in 1934 by antisemitic hecklers, Leo Reuss found a daring way to hide in plain sight




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Discover the Mysteries of Italy's Park of Monsters, a 16th-Century Garden Filled With Strange, Colossal Stone Creatures

The Sacro Bosco's meaning is the subject of debate, with scholars alternatively describing the sprawling complex as a memorial, an allegorical site or a tribute to ancient civilizations




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This 19th-Century 'Toy Book' Used Science to Prove That Ghosts Were Simply an Illusion

"Spectropia" demystified the techniques used by mediums who claimed they could speak to the dead, revealing the "absurd follies of Spiritualism"




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To Divine the Future, the Ancients Relied on These Chance-Based Fortune-Telling Tools

Texts like the "Sortes Astrampsychi" promised insights on clients' love lives, career prospects, financial woes and families




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One of America's First Spectator Sports Was Professional Walking

Before fitness influencers made getting your steps in a trend, pedestrianism had the nation on their feet




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When White Supremacists Staged the Only Successful Coup in U.S. History

The 1898 Wilmington massacre left dozens of Black North Carolinians dead. Conspirators also forced the city's multiracial government to resign at gunpoint




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The Surprising Artwork That Inspired Netflix's 'The Piano Lesson,' a New Movie Based on August Wilson's Award-Winning Play

A Romare Bearden print served as a starting point for the American playwright's 1987 drama, which follows a Black family's struggle to decide the fate of an ancestral heirloom




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How Spam Went from Canned Necessity to American Icon

Out-of-the-can branding helped transform World War II's rations into a beloved household staple




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N.B. Power wins long fight to raise rates 19 per cent over 2 years

N.B. Power has won approval to keep charging rates that it increased on customers by an average of 9.25 on April 1, and to repeat the increase next April, with only minor modifications.



  • News/Canada/New Brunswick

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Moncton man found guilty of murdering Joedin Leger

A jury has found a 20-year-old Moncton man guilty of second-degree murder in the 2022 death of an 18-year-old.



  • News/Canada/New Brunswick