Monday, March 30, 2020

Fabric masks in the time of coronavirus - video tutorial

Please see this video tutorial on how to make the best* fabric masks and how to properly wear it and take it off. Let me know if you have questions.

I will try to get a written step-by-step tutorial on this website soon. Stay tuned!

* my evidence-based opinion (I am a PhD-packing microbiologist at Stanford).

Thursday, March 19, 2020

Masks in the time of Coronavirus

Let's talk masks for a second. First of all, I am a PhD-packing microbiologist at Stanford and I consulted with a Stanford nurse regarding the fabric masks.
Image result for n95 mask
N95 mask - can protect against coronavirus if worn properly
The first picture is an example of an n95 mask. These are the only masks that can prevent you from breathing viral particles. It blocks 95% of very tiny particles. It only works when worn correctly when it forms a seal around your face. Healthcare workers need these and they are in short supply and quickly running out.
Image result for surgical mask
Surgical mask - will NOT prevent infection,
but helps limit spread of germs if wearer is sick.
Healthcare institutions in the US are also running out of these.
The second photo is a disposable surgical mask. If you are sick, these help stopping the spread of virus particles and bacteria (when you cough or sneeze, this mask will trap the particles). They also need to be worn properly, and are meant to be thrown away after use. IMPORTANT: these masks will NOT prevent your from catching novel coronavirus. The WILL limit the spread of novel coronavirus if you are infected.
The third photo is an example of a fabric mask. This mask operates under the same principles of the surgical mask and can help keep you from infecting others if you are sick (or an asymptomatic carrier of novel coronavirus). It is likely not as good as the surgical mask at absorbing particles you exhale, but it will do some good. IMPORTANT: these masks will NOT prevent your from catching novel coronavirus. The WILL limit the spread of novel coronavirus if you are infected. They NEED to be washed with soap and hot water after every use or virion particles can remain active. The more layers of fabric, the more particles are likely to get stopped. Crochet masks have lots of holes where particles can get though, so I'd recommend a fabric mask that you wash regularly if you go this route.
Extra benefit of wearing a fabric mask: people are more likely to keep the recommended 6 feet distance from you. 😷
Image may contain: text
Example homemade mask. Will NOT prevent infection,
but offers some benefits of surgical mask, with the additional benefit that
people will stay the f*ck away from you in public
MYTH: Masks are not a 'breeding ground' for the novel coronavirus. Viruses are not 'alive' on their own, although they can remain active in the air for a few hours and on surfaces for a few days. They need their hosts (humans for novel coronavirus) in order to replicate and spread. So, yeah, social distance it up!
Let's do our best to stop helping the virus spread! Now is the time to shelter in place as much as humanly possible. I am hunkering down for a month and then I will re-evaluate the situation and see. We need to all do whatever we can.

FYI: I have made this post public on my personal Facebook page (Heidi Arjes) - please ask any questions thre or in the comment box below. 

Saturday, December 15, 2018

Biofilm Knit Hat

I am thrilled to finally share this biofilm knit hat that I designed and knit last December! The pattern for this hat can be found here on Ravelry or directly here

I was excited to be asked if I could design a biofilm hat as I study bacterial biofilms at Stanford University. Click here for more about my research.

Bacteria are single cell organisms. The bacteria that I study, Bacillus subtilis is a soil-dwelling bacterium that is ~3-5 micrometers long. These bacteria can live on their own or they can "settle down" on a surface and form a biofilm. A biofilm is a group of cells that are held together by a substance that the cells produce and excrete. This substance (also known as slime) is a sticky substance that keeps the cells together. Once the cells are in a biofilm, they can adapt to take on different roles within the biofilm. For instance, the cells on the interior of the biofilm usually assume a more dormant role while the bacteria that are closer to nutrients and oxygen remain more metabolically active and can grow and divide. Biofilms are very important to study as several pathogenic bacteria can form biofilm infections in the body that are hard to treat. Bacillus subtilis, the strain that I study, is typically a soil-dwelling bacteria. However, the knowledge that I can gain through studying its biofilm formation can be applied to all types of biofilms including those that cause disease.

This hat is my version of a classical figure illustrating the developmental stages of a biofilm. This one represents a bacterial biofilm that forms on a surface in a liquid environment such as the bacteria Pseudomonas aeruginosa. Check out the movie I made below where I demonstrate how this knit hat illustrates biofilm development. If you want to learn more about biofilms, I'd recommend checking out the wikipedia page here.

Wednesday, May 23, 2018

Heidi attempts to tidy, part 1

tldr: I am starting the KonMari method's journey of tidying. Yarn brings me a lot of joy. I used Instagram to help define my ideal lifestyle. Scroll down for pretty pictures. :)

The life-changing magic of tidying up

I am going to join "The life-changing magic of tidying up" bandwagon and try out this method in the coming few weeks. I am viewing this process as a journey/ceremony/ritual of some sort and I cannot wait to get started! For fun, I thought I would share my process with you through my blog.

I definitely have a personality that gets fixated on projects and I can't exactly say what triggered this, but I went to the library last week to check out this along with "Spark Joy: an illustrated master class on the art of organization and tidying up". I nearly bought the book online, but then it seemed ironic to buy a book that I would run the risk of not getting joy out of and choosing to let go during the tidying process. The gist of the method is that you go through each belonging and keep those that elicit joy or happiness and bid a fond farewell to those that do not. I hope this will help free my mind and help facilitate a relaxed, content, and/or creative mood each time that I arrive home. I can highly recommend both books as I have already implemented a few tips into my daily life. I love how she shares the logic behind her method as well as clearly stating the "right ways" when there are definitive 'evidence supported' ways to store things (i.e. the kitchen should be organized for ease of cleaning up rather than keeping everything at hand, Marie Kondo discovered this after observing several kitchens in restaurants and found this was a common link). As someone who was looking for more of the step-by-step process and who is a more visual learner, I preferred "Spark Joy." However, if you have the time and means, both are delightful books to read and you might as well tackle them both if you are serious about attempting the journey.

I have already been through one informal round of this process. I had heard of the method, but I had not yet read the book(s) so I did not completely grasp the true extent of the wisdom and logic behind the process. When I moved to California in 2015, I used the joy factor to help pare down everything I owned into two checked bags and one carry-on that housed my vintage Kenmore sewing machine and yarn. It was so freeing to own so few items at one time. I moved into my apartment and discovered that I LOVE giving items a second life and having furnishings and household goods that have had a history before me (and getting great deals for much less than I would have paid new). Except for a desk, my couch, and my mattress, pretty much everything in my apartment was found at an estate sale, garage sale, or on Craigslist.

Reconciling my love of crafting supplies with the minimalism movement

As a crafter, I was initially concerned that this minimalism often seems at odds with those who spend significant time (and receive significant joy) from creating. In particular, I love knitting and have one section of my kitchen cupboard full of yarn, which gives me pleasure whenever I open the doors. I also love to sew and have 3 sewing machines (2 vintage) as well as a couple of boxes full of fabric I have accumulated from yard sales. (check out my Instagram, I'll be sharing some "before" photos soon").

While I have not started sorting yet, I love KonMari's non-judgemental approach. If something brings you joy, keep it and cherish it. So, if all of my skeins of yarn end up bringing me joy, I can gleefully put them in the keep pile and find a home for them in my apartment with no remorse. This method really forces you to be true to yourself and I suspect that is one of the reasons it is so successful.

As an aside, I recently was at an estate sale where a craft room was jam packed with yarn, sewing supplies, and a knitting machine (that I was gifted for free after it did not sell!). I told the woman running the estate sale that I volunteer at a school to teach kids to knit and she donated 3 buckets of yarn to the cause. During our conversation in this crowded room above the trunk full of yarn, the woman running the estate sale commented to me that this woman was quite the hoarder. I was a bit affronted by that as, even though it was the last day of a 3-day estate sale, the rest of the house did not look that cluttered at all and you could tell from the pictures to advertise the sales that the house was not that of a hoarder. Also, although I try to keep my yarn stash in check, I cannot often bring myself to get rid of yarn that has the potential to be whatever I dream up for it! It makes me happy just to sort through my yarn every so often and imagine future projects and dream of a life of leisure where I can create all day whatever comes into my head! I am well on my way to having that much yarn, and I don't consider stocking up on supplies of yarn and fabric as a negative, in the way the word "hoarding" is so often used as.

Step 1: imagine your ideal lifestyle

The first step of the KonMari method is to imagine your ideal lifestyle. She insists that you be quite thorough and deliberate in this process as this will help inform what gives you joy and the end result. To help with this, I took to Instagram and looked through the #interiordesign hashtag to find images that resonated with me. As you can see from the posts below, in general I love well-lit clean, simple, modern styles without much clutter. I also love a touch of traditional elements.

However, my Instagram perusal quickly turned into looking for yarn storage (as that just makes me happy - I browsed the #flashyourstash hashtag for probably 30 minutes with a smile on my face). I have found that I have a much higher tolerance for what some would consider "clutter" when it comes to yarn and crafting and the following photos spoke directly to my heart. To me this makes perfect sense. I can organize your yarn (and I take pleasure in organizing it at least once a year or after any large yarn acquisition) to my hearts delight, but it'll never be perfect, nor should it. I would never want my yarn storage so perfect that I did not want to begin a new project as I might mess up my yarn. I just love it too much to structure it in that way.

See the below posts as examples of what design styles and yarn storage please me the most:

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Wednesday, April 11, 2018

Doctor Who inspired knit hat

Sometimes I try experiments with my knitting outreach activities. This one worked out better than even I expected. I ran a "Design your own knit hat" contest as part of my Science Knits display at the California Academy of Science's Maker's night last Spring. I provided graph paper and let the attendees fill in the boxes to design their own patterns. This design was the winner. It was a team effort between two very dedicated Whovians. I wonder if they could tell I also love Doctor Who, because how could I not pick this awesome design! With a few tweaks it became this hat that features the TARDIS, Daleks, cybermen, and K-9. Isn't it so cool!! I sent this original hat to the designers as their reward for winning, but I may have to make another one for myself in the future!

The pattern is listed here on Ravelry and here on Craftsy [link broken until I get time to upload pattern to Craftsy...]. You can also purchase it directly here

Saturday, March 31, 2018 - the Etsy of the Resistance

Tuesday, March 6, 2018

Evil Eye Gloves - Crochet Version

Krista Suh's newest craftivist movement is to create a sea of eyes at the March for our Lives to show congress we are watching and we are holding them accountable. She is organizing the effort to collect gloves in Washington, DC. Check out her website here to see where to send the gloves.

Help create a Sea of Eyes at the March for Our Lives
I was immediately on board and I designed my own knit colorwork version (see it here). I challenged my friend Silke, the most talented crochet designer I know, to design a crocheted pair of gloves. She did not disappoint and came up with these awesome gloves. These glove are not simply an eye appliquéd onto simple gloves, they are just one layer throughout. She enlisted her friend Stefanie to help her write up the pattern. Stefanie originally created the pattern in German and then translated it to English. Check out more of Stefanie's designs here: They gave me permission to put the English pattern on my website and I am honored to help share it with everyone.

GET THE PATTERN HERE> Click here to download the pattern. Click here to see the original German version of the pattern.

This pattern is very thorough and has step-by-step instructions so hopefully even beginning crocheters can make it. Comment below if you have any questions about the pattern and I'll run them by Silke and Stefanie.

This crochet eye could also be sewn onto simple knit or crochet fingerless gloves.

Silke modeling her gloves.

Wednesday, February 21, 2018

Evil Eye Gloves

This week, Krista Suh (the Pussyhat Project creator) launched her next craftivism project. Just like she created a "sea of pink" for the Women's March, she wants to create a "sea of eyes" at the 2018 March for our Lives. She enlisted Kat Coyle (Pussyhat original designer) to design knit fingerless gloves with eyes embroidered into the palm. These eyes will show those in power that we are watching them and we will hold them accountable for their actions. Krista is leading the effort to have gloves sent to DC to support the students that will be marching. Her initial goal is 438 pairs of gloves - one pair to represent each person killed or injured in school shootings from 2014-present. I like to imagine these gloves giving representation to the victims, a symbolic gesture that the victims are present and watching in spirit. Please take the time to check out Krista's webpage for the original evil eye glove pattern and more details about the project and where to send gloves in DC (

Click here to get a pdf of my pattern. I designed my gloves in the round version of the Evil Eye Mitts using stranded colorwork to add the eye design.  If you have any questions about the pattern or find a mistake, please let me know!

Per Krista's request please share your projects using these hashtags on social media: #evileyegloves #marchforourlives

I had a request for a chart with the thumb gusset directions included. Here it is with the thumb gusset directions in words to the right for the 32 stitch cast on. The thick lines indicate where I would place stitch markers if using magic loop:

Here it is without lashes - (for the 32 stitch cast on):

Saturday, February 10, 2018

Ant Knit Hat

I designed this hat to feature Dr. Deborah Gordon's work with harvester ants. To see a synopsis of her work and Dr. Gordon modeling the hat herself, check out my blog post here. This hat features two pairs of harvester ants that are interacting through their antennae. Dr. Gordon provided a lot of help with the design, insuring that the ants would be interacting through their antennae, just like they do in the environment. 

The pattern for this knit hat is available here on Ravelry or can be purchased directly here.
Harvester ants interact with each other by briefly touching antennae  

Tuesday, February 6, 2018

Scientists in Stitches - Dr. Deborah Gordon

This "Scientists in Stitches" post features Dr. Deborah Gordon, a professor at Stanford in the Department of Biology. Dr. Gordon studies the collective behavior of biological systems using harvester ant colonies. 

Ants are social insects that operate without central control. This means that there are not 'boss' ants to direct the behavior of underling ants. Harvester ants gather seeds from the environment. They leave their protected colony and enter harsh desert conditions in search of scattered seeds. Once an ant finds a seed, it returns to the colony. As the ant returns to the colony, it will briefly touch antennae with another ant and that ant will go foraging. 

In particular, Dr. Gordon investigates how harvester ants use these interactions to regulate behavior and how these small local interactions direct the dynamics of the entire colony. Ants use these interactions as a proxy for how much food is available. If there are a lot of seeds near the colony, ants will find seeds and return more frequently, thus sending more ants out to collect all the seeds. When there are fewer seeds, the ants meander longer and cover the area more thoroughly before they find a seed and return, reducing rate of ants leaving the nest.

Dr. Gordon's work is relevant to studying other networks without central control such as other biological systems and, perhaps even networks such as the internet. To learn more about Dr. Gordon's work, check out her lab's website here, her TED talks in 2003 and 2014, and her article in Scientific American

If you would like to see more photos of the hat and get a link to the pattern, check out this blog post.

Dr. Gordon showing off some of her ant paraphernalia while wearing
her hat that features ants interacting 

Tuesday, January 9, 2018

5 science communication instagram accounts to follow in 2018

Follow me on instagram for more science outreach posts in 2018
One of my New Year's goals is to do more science communication on social media and here on my website. I am off to a good start with the Swimming Bacteria Knit Hat post that explains bacterial swimming that I published last weekend.

As part of my motivation, I took to Instagram and searched through #scicomm posts to find new accounts to follow. Here are a few that stuck out to me. If you have an Instagram account where you share science outreach posts or if you follow any awesome science communicators, please leave the information in a comment below! I'd love to feature more in the future.

Here are a few science communicators to follow on Instagram:

1) Sunburnedscientist - I love the conversational style and questions posed by @thesunburtscientist. Follow this UC Santa Barbara PhD student for some provocative questions and insights into everyday scientific experiments.

Electricity is weird. Can you define it? If I were to try, I’d say it’s the result of a special kind of force that both originates from & acts upon a charged object. • I bring this up because it’s (1) just fun to think about something so abstract yet actually physical and (2) it’s a totally appropriate topic for this image of an electrocuvette. • • • When electric charges move, they form what is called a current. Think: electrons. Why would they move? Well, in my definition of electricity, there’s some force acting on them. Indeed, electricity is the attractive or repulsive effect of a charge on a neighboring charge. But electricity cannot propagate through a vacuum (which here means a space devoid of atoms). Electricity needs a conduit. You know all those warnings on your hair drier, telling you to keep it out of water? Turns out all the dissolved ions found in water (=salt) can conduct charge quite well. That’s because the ions are also charged, meaning they have lonely electrons which are free to move about. The push or pull of an electric field moves these electrons through the material their parent atom is found in... resulting in propagation of the electric field. Thus, electricity is the movement of electrons through a medium of charged atoms. • • Water isn’t the best electrical conduit, though. The best material for conducting an electric current is actually metal. EVERY atom that forms a conducting metal has electrons that can move about, meaning that the entire object is dense with “conductable” material (in contrast the variable number of salt ions in liquid water). Indeed, electricity can be propagated near the speed of light in metal lattices. • • • By now you might have noticed that the cuvette shown above appears optimized for conducting electric currents (you’d be correct). To use this thing, the cuvette chamber is filled with bacteria and an electric field is applied, which opens up the cell membranes and also creates an ionic driving force (the electric field). If we add DNA to the culture prior to applying the current, we can force the cells to uptake that new DNA. Pretty cool, right? 🤙 #Physics + #Biology 😁
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2) Mouse_kween - She only has two posts so far, but I hope to see more from her in the future. She promises to deliver science communication that millenials can relate to.

A post shared by Mouse Kween 🐭👑 (@mouse_kween) on

3) travelingcassin - stories from nature, traveling, research, and life (full disclaimer, Loren is a close friend and my first featured "Scientist in stitches"). I love Loren's nature pictures and accompanying explanations to the underlying science.

4) Katcholamine - Kat has been designing these awesome science "stickers" and animations. If you are a scientist, you will love Kat's interpretation of lab wins and fails. (Full disclosure: Kat is also a friend of mine! I made her this poop hat to celebrate her thesis as one of my #knityourPhD projects.

5) Craftimism! Yup, that's me! I could not resist some shameless self-promotion and as I am gearing up for even more science outreach as well as knitting and craftivism in the new year, you should most definitely follow me on Instagram!
After pic of one of my bacterial growth curve experiments (swipe left to see the before and a side-by-side shot). . I put a small amount of bacteria into some clear media (media = food for bacteria, see second photo). There are so few, you can't even see them and the media is very clear. As the bacteria grow and divide, the media starts to get cloudy (seen in first photo). This cloudiness can be measured with a machine that measures how much light can make it through the solution. For a clear solution, almost all light can go through, but in one with a lot of bacteria, much of the light will be blocked, resulting in a higher density measurement. By taking measurements periodically while the bacteria grow, I can tell how well my bacteria are growing! Fun, right! Look/listen to yesterday's post to see/hear the plate readers in action! ... Each well in this plate has a different bacterial mutant, so I can compare the growth of each mutant to find ones that look different, and then I can look at the mutation to see why they might grow differently. Plus, I am measuring 8 plates at a time to see growth in different media and with dyes to see cell death and energetics. Fun! I'm excited to process the data next week! #scienceoutreach #womeninscience #womeninstem #steminist #scicomm #microbiology #heidithebiologist #biologist #microbiologist #growthcurves #lifeofapostdoc #postdoclife #bacteria #experimenting #experiment #biologist #sciencecommunication #talknerdytome
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Saturday, January 6, 2018

Swimming Bacteria Knit Hat

My latest science knit shows rod shaped bacteria swimming around the brim of the hat. The pattern for this hat can be found here on Ravelry or purchased directly here

These bacteria could be Escherichia coli or Bacillus subtilis or any other rod-shaped bacteria that have flagella over their body. 

Flagella behavior during tumbling and swimming
The flagella on these bacteria are peritrichous, which mean they surround the cell. The flagella are controlled by a molecular motor and the motor can either spin clockwise or counterclockwise. When all of the flagella on the cell spin counterclockwise, the flagella can propel the cell, as shown on this hat. When the flagella spin clockwise, they spread out and thus have no net force so cannot propel the cell anywhere. Instead of going in a direction, these cells “tumble” and basically somersault in the same place to change direction so when the flagella spin the other way again, they can set out in a different direction. These periods of “running and tumbling” allow the bacterium to explore its environment. During this exploration, when a bacterium is swimming toward nutrients, it can adjust the durations of running and tumbling so it is running for longer periods and tumbling less, thus biasing the movement toward the nutrients, in a process that is called “chemotaxis.” The bacteria on my hat are all swimming, although I considered making a version of the hat with tumbling cells as well. 

See the movie below for a video that I took of my favorite bacterium Bacillus subtilis. Some cells are stationary as they are stuck between an agar pad and a glass coverslip while others are in an area that is a bit wetter and they can swim around. This is best viewed fullscreen to better see the little organisms. It is a very short video, so you may have to hit replay to catch the action.

Full disclosure: this video was the result of an experiment that did not work. I didn't let the microscope slide dry enough before imaging and my bacteria were still swimming around. I made the most of the situation and filmed my swimming bacteria for this blog post (and I repeated the experiment to get the information I was looking for). Experiments often do not work or give inconclusive results - we as researchers learn to deal with failure very well and just keep plugging along and listening to the data to learn about the world around us. It is fascinating!

Wednesday, November 29, 2017

P*ssyHat by Craftimism

My friend Lala modeling her hat
Okay, okay, so I know I am about a year late to the game posting about the Pussyhat Project. I had heard of the movement before the Women's March last year, but I did not contribute any hats in time for the march. Instead, I made this awesome knit uterus hat for my friend Erin and liked it so much I made one for myself! In February, my uncle requested a "Pussy Hat" for my aunt and I finally made my first Pink Pussyhat! I used the dimensions from the "official" pattern but adjusted it to be knit in the round and my looser gauge. After that, I made another Pussyhat for my friend Lala and I made a few variations of pussy hats for people going to the science march. A printer-friendly version of my pattern can be found here.

Saturday, October 28, 2017

Shark Knit Hat

I designed this Shark Knit hat pattern for a friend of a friend who really loves sharks.

As a backstory, the friend (who did not know how to knit at the time) paid for a ridiculously difficult shark sock knitting pattern. He learned that I knit and showed the pattern to me. After laughing and saying I would never make those socks, I said that instead I would design a shark knit hat - as that is more of my thing. I have since taught this friend how to knit. We will see if he ever decides to tackle those socks!

Thus, this pattern was born. You can get it here on Ravelry, here on Craftsy, or buy it directly here. Enjoy!