Genetically encoded calcium indicators (GECIs) allow for the noninvasive evaluation of neuronal activity in vivo, and imaging GECIs in Drosophila has become commonplace for understanding neural functions and connectivity in this system. GECIs can also be used as read-outs for studying sleep in this model organism. Here, we describe a methodology for tracking the activity of neurons in the fly brain using a two-photon (2p) microscopy system. This method can be adapted to perform functional studies of neural activity in Drosophila under both spontaneous and evoked conditions, as well as during spontaneous or induced sleep. We first describe a tethering and surgical procedure that allows survival under the microscopy conditions required for long-term recordings. We then outline the steps and reagents required for optogenetic activation of sleep-promoting neurons while simultaneously recording neural activity from the fly brain. We also describe the procedure for recording from two different locations—namely, the top of the head (e.g., to record mushroom body calyx activity) or the back of the head (e.g., to record central complex activity). We also provide different strategies for recording from GECIs confined to the cell body versus the entire neuron. Finally, we describe the steps required for analyzing the multidimensional data that can be acquired. In all, this protocol shows how to perform calcium imaging experiments in tethered flies, with a focus on acquiring spontaneous and induced sleep data.

Sleep studies in Drosophila melanogaster rely mostly on behavioral read-outs to support molecular or circuit-level investigations in this model. Electrophysiology can provide an additional level of understanding in these studies to, for example, investigate changes in brain activity associated with sleep manipulations. In this protocol, we describe a procedure for performing multichannel local field potential (LFP) recordings in the fruit fly, with a flexible system that can be adapted to different experimental paradigms and situations. The approach uses electrodes containing multiple recording sites (16), allowing the acquisition of large amounts of neuronal activity data from a transect through the brain while flies are still able to sleep. The approach starts by tethering the fly, followed by positioning it on an air-supported ball. A multichannel silicon probe is then inserted laterally into the fly brain via one eye, allowing for recording of electrical signals from the retina through to the central brain. These recordings can be acquired under spontaneous conditions or in the presence of visual stimuli, and the minimal surgery promotes long-term recordings (e.g., overnight). Sleep and wake can be tracked using infrared cameras, which allow for the measurement of locomotive activity as well as microbehaviors such as proboscis extensions during sleep. The protocol has been optimized to promote subject survivability, which is an important factor when performing long-term (~16-h) recordings. The approach described here uses specific recording probes, data acquisition devices, and analysis tools. Although it is expected that some of these items might need to be adapted to the equipment available in different laboratories, the overall aim is to provide an overview on how to record electrical activity across the brain of behaving (and sleeping) flies using this kind of approach and technology.

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.

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

Trevor Lewis was a corporal in the Canadian Armed Forces who tried to bury the memories from his deployment in Afghanistan. They all came back in 2021 after the fall of Kabul. This story is how he made peace with his time in that country.

Questions included whether the province plans to renew the NHL tourism partnership deal for a second year, how much that renewal would cost, and even the date on which a second year would begin. 

The City of Winnipeg wants security guards at the Millennium Library to receive a living wage, but councillors recently rejected a motion that would have made a living wage mandatory for all city staff and contractors.

The Interior B.C. city is reviewing its policies for public hearings following the incident.

The Florida Panthers have given out another big extension — this one, to their Stanley Cup-winning coach. Paul Maurice and the Panthers have agreed on an extended contract, the team announced Tuesday.

A driver killed 35 people and severely injured another 43 when he deliberately rammed his car into people exercising at a sports centre in the southern Chinese city of Zhuhai, police said Tuesday.

Now that all of Canada's Olympic curling teams are finally set, CBC Sports' daily newsletter takes a look at the three tournaments.

Sleep is likely a whole-brain phenomenon, with most of the brain probably benefiting from this state of decreased arousal. Recent advances in our understanding of some potential sleep functions, such as metabolite clearance and synaptic homeostasis, make it evident why the whole brain is likely impacted by sleep: All neurons have synapses, and all neurons produce waste metabolites. Sleep experiments in the fly Drosophila melanogaster suggest that diverse sleep functions appear to be conserved across all animals. Studies of brain activity during sleep in humans typically involve multidimensional data sets, such as those acquired by electroencephalograms (EEGs) or functional magnetic resonance imaging (fMRI), and these whole-brain read-outs often reveal important qualities of different sleep stages, such as changes in frequency dynamics or connectivity. Recently, various techniques have been developed that allow for the recording of neural activity simultaneously across multiple regions of the fly brain. These whole-brain-recording approaches will be important for better understanding sleep physiology and function, as they provide a more comprehensive view of neural dynamics during sleep and wake in a relevant model system. Here, we present a brief summary of some of the findings derived from sleep activity recording studies in sleeping Drosophila flies and discuss the value of electrophysiological versus calcium imaging techniques. Although these involve very different preparations, they both highlight the value of multidimensional data for studying sleep in this model system, like the use of both EEG and fMRI in humans.

Fourth win in five years reinforces company's market leadership and drive to make product design easier and more productive

'Breakaway link' is key feature in new, safer utility connector

Medical industry manufacturer reducing R&D costs, time to market, and scrap by up to 50 percent

Donn McKinney Looks to Create a Fully Functional, Fleet of Hollywood-Quality Battleships for Museums and Ports

Apple Musicis turning its "100 Best Albums" list into a luxurious collectible book, bringing iconic records from the screen to your shelf.

A zeal for the Jezreel Valley overcomes fear and insecurity.

When specific medicine is not available during a medical outreach, OM Guatemala sees God miraculously provide for one mother in need.

From an island of 1.3 million, Lisette Williams was called to go abroad on OM’s ships and share the love of Jesus with the world.

The impact of coaches' ministry in the lives of nominal Christian and majority-faith background athletes.

As war continues in the east of Ukraine, refugees flood Odessa. OM cannot turn a blind eye to its new neighbours.

A team of volunteers and doctors attended to over 300 people in a town almost destroyed by an earthquake in 2007.

More than 800 children were impacted by the Festival of Smiles 2011 that took place in the indigenous community of Talamanca, Costa Rica.

When COVID-19 hit, two early-childhood centers put their competition aside to work together to support families during the pandemic. Here's how they did it.

New sheets outlines how districts can support English-learner students, but concedes that "schools may not be able to provide all services in the same manner they are typically provided."

A new report urges districts to pay close attention to how they choose and use technology for students who are not yet fluent in English.

Would measurement approaches based on "learning growth" resolve some of the concerns over NCLB?

Missouri’s educational technology efforts, once fueled by $15 million to $20 million a year in state funding, have been running on fumes from the state for the past three years, according to Deborah K. Sutton, the instructional technology director for the Missouri education department.

At present we reward quantity, not quality. The door could be opening for that to change, argues Johan Fourie.

Scholars have identified several reasons why cities want to host the Games, and there's little evidence to support some of the claims. But that doesn't mean it's not worth doing, says Johan Fourie.

Innovations that schools developed during their rapid transition to online instruction could inspire them to "rethink education," U.S. Secretary of Education Betsy DeVos said at a web conference with reporters.

To help ease the transition to remote instruction, educators have launched virtual professional learning communities to share resources, ask questions, and give advice.

A Kansas teacher of the year explains her approach to offering super engaging professional development in a virtual setting.

Growth mindsets are an important tool for battling racial bias in the classroom and helping students through difficulties posed by the pandemic.

Anivesh Sinha is one of the graduate research assistants working with a team of faculty and students from five Commonwealth Campuses, with funding from a University Presidential Public Impact Research Award, to help Pennsylvania nonprofit organizations improve their cybersecurity practices.

Districts could face a rising tide of special education-related lawsuits and complaints when schools resume, experts say, if they still cannot offer the services that students with disabilities missed out on for months.

When the brain experiences an injury, it can be difficult to definitively diagnose a concussion as the trauma is often limited to inside the skull and cannot be accurately assessed, according Reuben Kraft, a professor of mechanical engineering at Penn State. Kraft's research team is using computational methods and tools — such as custom mouthguard sensors — to model and predict injury in the human brain. 

As 1 million people head to cast ballots, the election results are likely to be announced on Monday.

The Richard King Mellon Foundation recently awarded $392,000 to Penn State to build a strong science- and technology-focused workforce in the state’s Mon Valley region through collaboration and virtual, augmented and mixed reality trainings and tools.

The Berks LaunchBox in partnership with Penn State Berks will host its free 3D Modeling and Printing Workshop for Manufacturing Companies from 3 to 5 p.m. on Tuesday, Nov. 12, in Reading, Pennsylvania.

How do you translate what you learned in a semester-long course to a community celebration for an audience ranging in age from kindergarteners to senior citizens? That was the challenge to Penn State Berks students in the “Taylor Swift, Gender and Communication” course, and they rose to the occasion.

Very carefully, experts say, while understanding that federal laws governing special education were not written with online education in mind.

The requests put the nation's special education administrators in conflict with disability rights advocates who fear waivers will place millions of special education students at risk.

Districts could face a rising tide of special education-related lawsuits and complaints when schools resume, experts say, if they still cannot offer the services that students with disabilities missed out on for months.

A new digital guide aims to identify students missing out on special education services and supports during distance learning.

A new U.S. Government Accountability Office report found that the needs of students with IEPS and those who are learning English-language skills were not often met after the pandemic struck.

As the cold weather approaches, it’s important to protect your family from the flu, COVID-19 and RSV. A Penn State Health pediatrician shares some simple tips to help keep everyone healthy.