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Farro with Roasted Butternut Squash

A wonderful farro and roasted butternut squash recipe. Balsamic roasted butternut squash, deeply toasted walnuts, and nutty farro come together in this delicious recipe.

Continue reading Farro with Roasted Butternut Squash on 101 Cookbooks




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"Square Dancers" - Shimmer Quilt

Kitty Sorgen, quilter extraordinaire, and Jenny Bowker, the pattern developer, are to blame for this madness! Shimmering Triangles Jenny calls it, and shimmer it does. In fact, it can be over done to the point where it's difficult to look at. But not Kitty's... Kitty, a member of our local guild and the best colorist I know, brought her shimmer quilt to Wednesday night quilting a few months ago, and

WHAMMMO!

I fell in love, bonkers, totally in love with her quilt. This isn't a great photo, but here it is, Kitty's shimmer quilt...


It's so complex, at first I couldn't even figure out what was a block, squares looking like diamonds, color everywhere, blending in some places, shimmering in others. That day, on the spot, enough of us signed up and paid, filling a one-day class instantly.



The class was on Feb. 21, 2015. Most of the students got a block finished in class, some even finished two blocks. Each block is 16" square (finished), and has 69 pieces. Below is one block, showing the construction of it.



Me? Nope. I didn't sew a stitch. Long after the other students had finished arranging their fabrics on the design wall, I was still struggling with the concept, of how to get shimmer, but not too much shimmer, still arranging my fabrics (photo below).


It was really difficult to imagine what would shimmer, what might be too contrasty and shimmer too much (for my taste), and what would have too little contrast and thus not shimmer at all.


At home, I laid it all out on my work tables again, rearranging and rearranging the fabrics over and over again. The trick, in my opinion, is to work the diagonals. I began with a layout of focal fabrics, in my case "painterly floral prints," leaving space between them for the companion fabrics. Then choose companion "read as solid prints," placing them at the corners of the focals. Like Kitty, I decided to repeat the companions diagonally between two focals. I don't know if this even makes sense, but maybe you can see it in the layout above.


Silly me, I thought sewing it, once I got all the fabrics placed, would be a piece of cake. NOT! Well, technically speaking, sewing it is OK. Although it does take some time and attention to detail to get all the half-square triangles square, and the points nice and pointy.


But cutting the triangles is another matter. To make the colors and shapes flow, it's important to blur the line of the focal square by blending the design/color outward through the half-square triangles. Above is an example of one that worked pretty well, because you can only barely discern the square of focal fabric in the center of the block.


And here is some fabric I turned into Swiss cheese trying to get triangles that would bring the focal fabric design outward, tricking they eye, making it look like a diamond rather than a square. (Sorry, I didn't take a picture of that particular finished block.)


I make the half square triangles using paper piecing, with a free, downloaded template printed on 16 pound copy paper. Paper piecing has a learning curve, yes, but it does make for very accurate piecing, such that I didn't have to trim any of the finished blocks at all!


Here is a picture of four finished blocks. You can see the way the companion fabrics repeat diagonally to form a 4-patch block between the focal fabrics. These two fabrics need to be close in value and color. If there is too much contrast, it draws the eye away from the focal fabrics and shimmering triangles. In the case above, I think the orange and pink contrast a little too much. Also on the left the lighter and darker green is also a bit too contrasty.  Fabric choices are difficult and important... Any one companion fabric has to work with two focal fabrics and the adjacent companion fabric, which in turn has to work with it's two adjacent focal fabrics. Sound complicated and challenging? It is!


It took many days (lost count) to finish the first half of the blocks (10 of 20)... and many more to finish the last 10 blocks... a bit character building. Many times, I told promised myself I would never do paper piecing or make another shimmer quilt again in my whole life!


Here I've finished all 20 blocks. I've moved all the furniture out of the studio, and put it on the floor to "audition" border fabrics. Most of the shimmer quilts I've seen do not have borders, but I wanted to make it a bit bigger so it could be used for a bed quilt.


This is how it looks all finished, before quilting it, 90 x 74 inches.

Since the throat of my old machine is much too narrow to free-motion quilt a piece this size, I decided to get a professional to quilt it. But first I agonized some about how to do it. At first I thought it would be good to fussy quilt, making flowers in the companion fabric areas and vertical vines with leaves over the focal fabrics. This was my sketch for the idea.


But then I saw a few quilts done like that, and the fussy quilting looked too busy, competing too much with the shimmer. So finally, I decided on using a double-leaf, free-motion edge-to-edge design. I named my quilt Square Dancers, because of the colorful costumes, movement, and squares.

Now that it's finished, guess what?  I started gathering fabrics for my second shimmer quilt. I want a spring-summer quilt for my bed in softer, lighter colors. It needs to be bigger than the first one, at least 36 blocks, to work on a queen size bed. Here are some of the fabrics I've found so far:





These are mostly designs by Philip Jacobs, one of the Kaffe Fassett Collective designers. I love his colors and designs! I will use other fabrics in my stash, but more than half of the 36 focals will be like these.

It will be fun to try this again, to apply what I've learned on the first one, to try to improve my fabric choices, always with the goal of some shimmer (but not too much) and good flow throughout the quilt. I'll also try to pick up my speed a bit, without sacrificing accuracy in the piecing.

Expect a post about #2 shimmer quilt in a couple of months. Right now, I'm still gathering fabrics.












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M/W Squash vs Drexel

M/W Squash vs Drexel




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Men's Squash vs Navy

Men's Squash vs Navy




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How to spend a weekend in Bilbao, the Basque country's artistic capital




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Vida em lua de Urano? As revelações de nova pesquisa sobre condições do planeta

Dados enviados pela Voyager 2 em 1986 mostravam que as luas de Urano eram completamente diferente do resto do Sistema Solar




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Uncapped Bouchier and Kemp in England Test squad

Maia Bouchier and Freya Kemp could make their Test debuts after being included in the squad for England's tour of South Africa.




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Australia v India – schedule, squads and how to follow on BBC

India travel to Australia for their five-Test series - here's everything you need to know including the schedule, squads and how to follow on the BBC.




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Arsenal captain Odegaard pulls out of Norway squad

Arsenal captain Martin Odegaard says he must "listen to my body" after withdrawing from Norway's squad.




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Leeds teenager Crew added to Wales squad

Leeds United teenager Charlie Crew comes into Craig Bellamy's Wales squad for their Nations League games with Turkey and Iceland.




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Sport | 'Dangerous' and 'arrogant': Rassie's latest Bomb Squad whips up fresh criticism up north

Rassie Erasmus' 7-1 variation of the Bomb Squad used against Scotland on Sunday set off a few tremors in the north, with Times writer Stephen Jones the latest to criticise the "dangerous" and "arrogant" tactic.




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Bridges and Wheels, Tricycles and Squares

Dr. Stan Wagon of Macalester College discusses the mathematics behind rolling a square smoothly. In 1997, inspired by a square wheel exhibit at The Exploratorium museum in San Francsico, Dr. Stan Wagon enlisted his neighbor Loren Kellen in building a square-wheeled tricycle and accompanying catenary track. For years, you could ride the tricycle at Macalester College in St. Paul, Minnesota. The National Museum of Mathematics in New York now also has square-wheeled tricycles that can be ridden around a circular track. And more recently, the impressive Cody Dock Rolling Bridge was built using rolling square mathematics by Thomas Randall-Page in London.




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Completing the Square




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Analysis-India's middle class tightens its belt, squeezed by food inflation




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Problem Notes for SAS®9 - 66438: You see the message "The informat $ could not be loaded, probably due to insufficient memory" after attempting to insert data into a MySQL database

For data that is being loaded from a SAS Stored Process Server, an insertion process might fail to a MySQL database with a warning, as well as an error message that says "During insert: Incorrect datetime value…"




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Problem Notes for SAS®9 - 66505: The OBS= option does not generate a limit clause when you use SAS/ACCESS Interface to PostgreSQL to access a Yellowbrick database

When you use SAS/ACCESS Interface to PostgreSQL to query a Yellowbrick database, the SAS OBS= option is not generating a limit clause on the query that is passed to the database. Click the



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Systematic Proteome and Lysine Succinylome Analysis Reveals the Enhanced Cell Migration by Hyposuccinylation in Esophageal Squamous Cell Cancer [Research]

Esophageal squamous cell cancer (ESCC) is an aggressive malignancy with poor therapeutic outcomes. However, the alterations in proteins and post-translational modifications (PTMs) leading to the pathogenesis of ESCC remains unclear. Here, we provide the comprehensive characterization of the proteome, phosphorylome, lysine acetylome and succinylome for ESCC and matched control cells using quantitative proteomic approach. We identify abnormal protein and post-translational modification (PTM) pathways, including significantly downregulated lysine succinylation sites in cancer cells. Focusing on hyposuccinylation, we reveal that this altered PTM was enriched on enzymes of metabolic pathways inextricably linked with cancer metabolism. Importantly, ESCC malignant behaviors such as cell migration are inhibited once the level of succinylation was restored in vitro or in vivo. This effect was further verified by mutations to disrupt succinylation sites in candidate proteins. Meanwhile, we found that succinylation has a negative regulatory effect on histone methylation to promote cancer migration. Finally, hyposuccinylation is confirmed in primary ESCC specimens. Our findings together demonstrate that lysine succinylation may alter ESCC metabolism and migration, providing new insights into the functional significance of PTM in cancer biology.




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Diagnostic Accuracy of [18F]FDG PET/MRI in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Metaanalysis

This study evaluates the diagnostic utility of PET/MRI for primary, locoregional, and nodal head and neck squamous cell carcinoma (HNSCC) through systematic review and metaanalysis. Methods: A systematic search was conducted using PubMed and Scopus to identify studies on the diagnostic accuracy of PET/MRI for HNSCC. The search included specific terms and excluded nonhybrid PET/MRI studies, and those with a sample size of fewer than 10 patients were excluded. Results: In total, 15 studies encompassing 638 patients were found addressing the diagnostic test accuracy for PET/MRI within the chosen subject domain. Squamous cell carcinoma of the nasopharynx was the most observed HNSCC subtype (n = 198). The metaanalysis included 12 studies, with pooled sensitivity and specificity values of 93% and 95% per patient for primary disease evaluation, 93% and 96% for locoregional evaluation, and 89% and 98% per lesion for nodal disease detection, respectively. An examination of a subset of studies comparing PET/MRI against PET/CT or MRI alone for evaluating nodal and locoregional HNSCC found that PET/MRI may offer slightly higher accuracy than other modalities. However, this difference was not statistically significant. Conclusion: PET/MRI has excellent potential for identifying primary, locoregional, and nodal HNSCC.




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Coronavirus Squeezes Supply of Chromebooks, iPads, and Other Digital Learning Devices

School districts are competing against each other for purchases of digital devices as remote learning expands to schools across the country.




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Why Seahorses Have Square Tails

Used more for grasping than locomotion, seahorse tails are both flexible and uniquely strong. (Video courtesy Dominique Adriaens, UGent)




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Oldest Known Macroscopic Skeletal Organism Was Masquerading as Fossilized Feces

Some researchers initially dismissed the remains of Palaeopascichnus lineari as teeny turds from a bygone era




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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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Whole-Mount Immunofluorescent Labeling of the Mosquito Central Nervous System

Mosquito-borne disease is a major global public health issue. One path toward the development of evidence-based strategies to limit mosquito biting is the study of the mosquito nervous system—in particular, the sensory systems that drive biting behavior. The central nervous system of insects consists of the brain and the ventral nerve cord. Here, we describe a protocol for dissecting, immunofluorescent labeling, and imaging both of these structures in the mosquito. This protocol was optimized for Aedes aegypti and works well on Anopheles gambiae tissue. It has not been tested in other mosquito species, but we anticipate that it would work on a range of mosquitoes, and, if not, our protocol will provide a starting point from which to optimize. Notably, a limited number of antibodies cross-react with Ae. aegypti proteins. This protocol is intended for use with validated antibodies and can also be used to test new antibodies as they are generated. It has been successfully used to visualize protein tags, such as green fluorescent protein, that have been introduced into the mosquito to amplify or detect their presence.




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Mosquito Larvae and Pupae Transport from the Field

Laboratory study of field-collected mosquitoes can allow researchers to better understand the ways variation within and among mosquito populations shapes burdens of mosquito-borne disease. The Anopheles gambiae complex comprises the most important vectors of malaria, but it can be challenging to keep in the laboratory. For some species of mosquitoes, especially An. gambiae, it is very difficult to bring viable eggs into the laboratory. Instead, it is preferable to collect larvae or pupae and then transport them as carefully as possible back to the laboratory. This simple protocol allows a researcher to start new laboratory colonies from larvae or pupae collected from natural breeding sites or proceed directly to their planned experiments. The use of natural breeding sites provides additional reassurance that the resulting colonies are representative of natural populations.




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Single-Sensillum Taste Recordings in Mosquitoes

In insects, gustatory neurons sense chemicals upon contact and directly inform many behaviors critical for survival and reproduction, including biting, feeding, mating, and egg laying. However, the taste sensory system is underexplored in many anthropophilic disease vectors such as mosquitoes, which acquire and transmit human pathogens during blood feeding from human hosts. This results in a big gap in vector biology—the study of organisms that spread disease by transmitting pathogens—because insect vectors closely interact with humans while selecting suitable individuals and appropriate bite sites for blood meals. Human sweat and skin-associated chemistries are rich in nonvolatile compounds that can be sensed by the mosquito's taste system when she lands on the skin. Taste sensory units, called sensilla, are distributed in many organs across the mosquito body, including the mouthparts, legs, and ovipositors (female-specific structures used to lay eggs). Each sensillum is innervated by as many as five taste neurons, which allow detection and discrimination between various tastants such as water, sugars, salts, amino acids, and plant-derived compounds that taste bitter to humans. Single-sensillum recordings provide a robust way to survey taste responsiveness of individual sensilla to various diagnostic and ecologically relevant chemicals. Such analyses are of immense value for understanding links between mosquito taste responses and behaviors to specific chemical cues and can provide insights into why mosquitoes prefer certain hosts. The results can also aid development of strategies to disrupt close-range mosquito–human interactions to control disease transmission. Here we describe a protocol that is curated for electrophysiological recordings from taste sensilla in mosquitoes and sure to yield exciting results for the field.




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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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Extracting DNA from Preserved Mosquito Blood Meals

Mosquito species vary in their host associations. Although some species are relative generalists, most specialize, to varying extents, on particular types of host animals. Mosquito host associations are among the most important factors that influence the transmission dynamics of mosquito-vectored pathogens, and understanding these associations can provide insight on how such pathogens move within ecosystems. Characterization of the host associations of mosquito species requires applying blood meal analysis to the largest possible sample size of mosquito blood meals. Processing large samples of mosquito blood meals can be time-consuming, especially when chain-termination sequencing is used, necessitating individual processing of each specimen. Various methods and commercially available kits and products are available for extracting DNA from mosquito blood meals. The hot sodium hydroxide and Tris (HotSHOT) method is a rapid and inexpensive method of DNA extraction that is compatible with the recovery of DNA from mosquito blood meals preserved on QIAcard Flinders Technology Associates (FTA) Classic Cards (FTA cards). FTA cards allow nucleic acids found in blood meals to be preserved easily, even in field conditions. DNA prepared using this method is suitable for polymerase chain reaction (PCR)-based blood meal analysis.




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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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Ticats quarterback Mitchell headlines 2024 CFL all-star squad

Bo Levi Mitchell is a CFL all-star for the third time. The Hamilton Tiger-Cats quarterback and East Division finalist for the CFL's outstanding player award was named to the 2024 all-star squad on Thursday.



  • News/Canada/Hamilton

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Introduction to Techniques Used to Study Mosquito Neuroanatomy and Neural Circuitry

Mosquitoes transmit deadly pathogens from person to person as they obtain the blood meal that is essential for their life cycle. Female mosquitoes of many species are unable to reproduce without consuming protein that they obtain from blood. This developmental stage makes them highly efficient disease vectors of deadly pathogens. They can transmit pathogens between members of the same species and different species that can provide a route for evolving zoonotic viruses to jump from animals to humans. One possible way to develop novel strategies to combat pathogen transmission by mosquitoes is to study the sensory systems that drive mosquito reproductive behaviors, in particular the neural architecture and circuits of mosquito sensory afferent neurons, the central circuits that process sensory information, and the downstream circuits that drive reproductive behaviors. The study of mosquito neuroanatomy and circuitry also benefits basic neuroscience, allowing for comparative neuroanatomy in insect species, which has great value in the current model species-heavy landscape of neuroscience. Here, we introduce two important techniques that are used to study neuroanatomy and neural circuitry—namely, immunofluorescent labeling and neural tracing. We describe how to apply these approaches to study mosquito neuroanatomy and describe considerations for researchers using the techniques.




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Establishing Colonies from Field-Collected Mosquitoes: Special Accommodations for Wild Strains

A researcher may have many reasons for wanting to establish new laboratory colonies from field-collected mosquitoes. In particular, the ability to study the diversity found within and among natural populations in a controlled laboratory environment opens up a wide range of possibilities for understanding how and why burdens of vector-borne disease vary over space and time. However, field-collected mosquitoes are often more difficult to work with than established laboratory strains, and considerable logistical challenges are involved in safely transporting field-collected mosquitoes into the laboratory. Here, we provide advice for researchers working with Aedes aegypti, Anopheles gambiae, and Culex pipiens, as well as notes on other closely related species. We provide guidance on each stage of the life cycle and highlight the life stages for which it is easiest to initiate new laboratory colonies for each species. In accompanying protocols, we provide methods detailing Ae. aegypti egg collection and hatching as well as how to transport larvae and pupae from the field.




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Design and Validation of Guide RNAs for CRISPR-Cas9 Genome Editing in Mosquitoes

CRISPR–Cas9 has revolutionized gene editing for traditional and nontraditional model organisms alike. This tool has opened the door to new mechanistic studies of basic mosquito biology as well as the development of novel vector control strategies based on CRISPR–Cas9, including gene drives that spread genetic elements in the population. Although the promise of the specificity, flexibility, and ease of deployment CRISPR is real, its implementation still requires empirical optimization for each new species of interest, as well as to each genomic target within a given species. Here, we provide an overview of designing and testing single-guide RNAs for the use of CRISPR-based gene editing tools.




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Taste Sensory Responses in Mosquitoes

Analysis of taste sensory responses has been a powerful approach for understanding principles of taste detection and coding. The shared architecture of external taste sensing units, called sensilla, in insects opened up the study of tastant-evoked responses in any model of choice using a single-sensillum tip recording method that was developed in the mid-1900s. Early studies in blowflies were instrumental for identifying distinct taste neurons based on their responses to specific categories of chemicals. Broader system-wide analyses of whole organs have since been performed in the genetic model insect Drosophila melanogaster, revealing principles of stereotypical organization and function that appear to be evolutionarily conserved. Although limited in scope, investigations of taste sensory responses in mosquitoes showcase conservation in sensillar organization, as well as in groupings of functionally distinct taste neurons in each sensillum. The field is now poised for more thorough dissections of mosquito taste function, which should be of immense value in understanding close-range chemosensory interactions of mosquitoes with their hosts and environment. Here, we provide an introduction to the basic structure of a taste sensillum and functional analysis of the chemosensory neurons within it.




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Mosquito Blood Meal Analysis

The host associations of mosquitoes vary by species, with some species being relative generalists, whereas others specialize, to varying extents, on a particular subset of the available host community. These host associations are driving factors in transmission dynamics of mosquito-vectored pathogens. For this reason, characterizing the host associations of mosquito species is critical for understanding the epidemiology of mosquito-vectored pathogens. Diverse methods have been used to associate mosquito species with their hosts. These typically include collecting mosquitoes that bite a restrained host (bait) or collecting wild blood-engorged mosquitoes and matching their blood meal to reference samples (blood meal analysis). Blood meal analysis refers to a collection of molecular techniques for determining the taxonomic identity of the source of a mosquito blood meal using cytological, serological, or DNA-based characteristics of the blood meal. Blood meal analyses that are based on DNA markers have advantages over cytological and serological methods and are effective for determining species-level identities of hosts from a broad range of potential host taxa. Here, we discuss effective techniques for analyzing blood meals.




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Mosquito Transposon-Mediated Transgenesis

Transposon-mediated transgenesis of mosquito vectors of disease pathogens followed the early success of transgenesis in the vinegar fly, Drosophila melanogaster. The P transposable element used in Drosophila does not function canonically in mosquitoes, and repeatable, routine transgenesis in mosquitoes was not accomplished until new transposable elements were discovered and validated. A number of distinct transposons were subsequently identified that mediate the introduction of exogenous DNA in a stable and heritable manner in mosquito species, including members of the genera Aedes, Anopheles, and Culex. The most versatile element, piggyBac, is functional in all of these mosquito genera, as well as in many other insects in diverse orders, and has been used extensively outside the class. Transposon-mediated transgenesis of recessive and dominant marker genes and reporter systems has been used to define functional fragments of gene control sequences, introduce exogenous DNA encoding products beneficial to medical interests, and act as "enhancer traps" to identify endogenous genes with specific expression characteristics.




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Mosquito Egg Development and Eggshell Formation

Anautogenous female mosquitoes, which ingest a blood meal from warm-blooded vertebrates to produce eggs, have become a valuable model organism for investigating signaling pathways and physiological processes that occur during egg development. Different molecular pathways tightly regulate the initiation of egg development and are governed by a balance among different insect hormones. Gravid (mature egg-carrying) females deposit fully developed eggs at the end of each gonotrophic cycle, which is defined as the time interval between the ingestion of a blood meal to oviposition. An intact eggshell protects the oocyte and embryo inside from external factors such as desiccation, physical damage, etc., and the various eggshell proteins are spatially and temporary deposited during oogenesis. Additionally, follicle resorption (oosorption) during blood meal–induced mosquito ovarian follicle development is an adapted physiological process that optimizes reproductive fitness. Mosquito oocytes grow and mature synchronously throughout oogenesis; however, during the later stages of oogenesis, some oocytes may undergo oosorption if sufficient nutrients are unavailable. This introduction highlights how mosquito egg development can be used to investigate follicular resorption and identify proteins involved in eggshell formation in Aedes aegypti mosquitoes.




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Unforgettable squeals of joy

Rex from the USA, volunteered for two months in the Baseball and Softball Programme alongside OMers Terry Lingenhoel and Suzanne Cole this spring.