We narrowed to 888 results for: URE

...guest blogger, Gary McDowell, executive director of Future of Research. On December 1st 2016, many postdocs...some cases reversing these decisions entirely. At Future of Research, we had been collecting data and documenting...published in F1000Research on November 2016. Due to the nature of the postdoc position, we viewed salary raising...FLSA updates was granted nationwide. Again, we at Future of Research believe that, while the mandate has... out about what their institution is doing from Future of Research over social media, not from their institution...actually getting paid, which we will be analyzing for future updates. But suffice it to say, salaries are showing...McDowell is currently the Executive Director of Future of Research. He is interested in advocating for...

...available, including those found at Addgene! Figure 1: Strategy for assembling the barcoded gRNA library...pool-clone them into the pAWp28 storage vector (Figure 1): Forward oligo: 5’- CACCGNNNNNNNNNNNNNNNNNNNGTTTGGGTCTTCGAGAAGACCTATTCXXXXXXXXC...the CombiGEM lentiviral vector backbone pAWp12 (Figure 2). Cloning from the pAWp28 storage vector to the...by NGS before beginning your experiments. Figure 2: Strategy for assembling barcoded combinatorial...and minimize off-target effects of CRISPR-Cas9." Nature biotechnology (2016). PubMed PMID: 26780180. PubMed...cells with a lentiviral CRISPR-guide RNA library." Nature biotechnology 32.3 (2014): 267-273. PubMed PMID...activation by an engineered CRISPR-Cas9 complex." Nature (2014). PubMed PMID: 25494202. PubMed Central PMCID...

...publishing, but still made it so she could “get exposure to the drug discovery process.” The ClonTracer...xenografts after cell implantation. Their goal was to figure out how to optimize protocols for in vivo screening...panned out quickly,” and was summarized in a recent Nature Medicine paper. In the publication, Bhang and coworkers...specifc, easily read sequences that can be used to measure their clonal abundance before and after a treatment... populations with resistance to both drugs. The future of ClonTracer Since starting her new role as an...populations are treated as they arise. In their Nature Medicine paper, Bhang and coworkers also looked...cancer therapy using high-complexity barcoding." Nature medicine 21.5 (2015): 440-448. Pubmed PMID: 25849130...

...workshops (see the Careers essays in the journals Nature and Science, for example). This blog post is about...write a manuscript. Consider questions like: What figures are missing? For example, are additional controls...been validated? How will the results fit into a future manuscript? You could easily spend a day or a ...experiment. However, by taking this time, you can help ensure that you understand the methodology and can have...the data and any recent relevant studies in the literature. Plus, presentations benefit from practice. If...and how your research fits in with the current literature. Finally, if you give your talk or poster to ...application and manuscript reviews, etc. You'll also meet future collaborators and get access to unpublished information...

...Transposons: The jumping genes. Nature Education 1(1):204. https://www.nature.com/scitable/topicpage/transposons-the-jumping-genes...retrotransposons are like retroviruses both in their structure and mechanism of replication. They contain two...and reverse transcriptase activities.    Figure 1: Overview of retrotransposon transposition. Retrotransposons... TEs have LTRs on both of their ends.    Figure 2: Overview of DNA transposon transposition. Modified...Transposon mutagenesis screens Transposons, by their nature, are mutagenic elements, which makes them a great...of DNA up to 10 kB in size in bacteria.   Figure 3: INTEGRATE system for RNA guided transposon insertion...Rev Genet 41:331–368. https://doi.org/10.1146/annurev.genet.40.110405.090448 Kumar A (2020) Jump around:...

...particles produced could not replicate. However, Mother Nature found a way to re-create a functional virus. Indeed...non-dividing cells is not restricted to in vitro cell culture as lentivirus-derived vectors are capable of transducing...your gene of interest into and is an important feature for your experiment; it must be chosen carefully...expression of your gene. The addition of Dox in the culture will then repress your gene of interest. This system...state and is expressed when Dox is added to the culture. This system is now used as it shows rapid gene...biosafety guidelines for more information and always be sure to consult your institution’s Biosafety Committee...cells start releasing viral particles into the culture supernatant and you can generally harvest the supernatant...

...  Figure 1: (Top) Polyclonal antibodies are produced in animals and consist of a mixture of antibodies...made from animals or hybridomas.   Figure 2: (Left) Figure 2: (Left) The light chain and heavy chain...Reproducibility crisis: Blame it on the antibodies. Nature 521:274–276 . https://doi.org/10.1038/521274a Begley...Raise standards for preclinical cancer research. Nature 483:531–533 . https://doi.org/10.1038/483531a Bradbury...Reproducibility: Standardize antibodies used in research. Nature 518:27–29 . https://doi.org/10.1038/518027a Bradbury... (2015) Antibodies: validate recombinants once. Nature 520:295–295 . https://doi.org/10.1038/520295b Bradbury...

...mCherry coding sequence in the antisense orientation (Figure 1, top). The entire DNA cassette would be flanked...include both Cre and FLP recombinases.   Figure 1 (modified from Schnutgen et al. Nat Biotech 2003...identical sites on one end of the DNA fragment (Figure 1, middle). A second recombination event then excises...DNA between the identical loxP or lox511 sites (Figure 1, bottom). Since only one loxP and lox511 site...switch conditional knock-in cassette. As shown in Figure 2, the cassette should contain a reporter DNA sequence...control expression of an optogenetic reporter would ensure that the reporter remains silent until a cell or...tissue-specific Cre is provided. Since the FLEx switch ensures Cre-dependent reporter expression, the potential...

...poly-uracil tract as shown in the figure to the right. The tertiary structure of the hairpin-DNA complex is...the transcript.   Figure 1: A predicted conserved secondary structure and sequence conserved Rho-independent...enzymes that cut RNA not protected by secondary structure. It is thought that poly(A)s are used to control...relies on a specific sequence and RNA secondary structure to induce transcript cleavage, similar to the ...motif and a downstream GU-rich region (shown in the figure below) releases the mRNA from the polymerase and...export and translation processes as well.   Figure 2: The conserved eukaryotic polyadenylation signal...

...field. Nobel Laureates and the ever expanding importance of RNA The second keynote lecture was presented...project on its 25th anniversary, how the NIH sees the future for genomics, and President Obama’s Precision Medicine...presented by Nobel Laureate Jack Szostak. Dr. Szostak’s lab continues its work on the origin of cellular life... two of the conference was kicked off by Nobel Laureate (and Addgene depositor) Craig Mello. Taking his...problem of antibiotic resistant bacteria. See the picture to the left for his list of the bacterial species...engineering. The final keynote presentation was by Nobel Laureate Thomas Steitz of Yale. He gave an update on new...conformation “not like DNA which has a boring structure.” That certainly summed up this conference—nucleic...

...little better. As a Master’s student, she had less pressure to publish and more freedom to attend conferences...legitimate brain exercise in developing a plan for the future. From good ideas to a SynBio startup At some point...them to see how feasible they were, conducting literature reviews and having weekly journal clubs outside...this process, we had an idea that survived the literature review, survived technical feasibility analysis... fearful of this technology and angry at the agriculture companies that produce GMO food plants. When ...idea, we knew it was a winner – although we didn’t figure out how we would accomplish the color change until...science, and to have a job that we enjoy and see a future in. And we decided to make education and outreach...

...not based on any existing protein structures, called Top7. Figure 1: Top7 receives the Nobel Prize...characterized it, producing crystal structures demonstrating “the structure is strikingly similar to the design...works and creating biological tools not found in nature. Dr. Baker’s team was the first to develop and ...wanted to create a new fold that is not present in nature (at least that we’ve seen so far!). They started...the biophysics of protein folding and selective pressures during protein evolution. The Baker Lab has deposited...

... like to make sure they are present at a very low concentration. So how do we make sure to catch all of...experiment because of poor reagent quality. To make sure our AAV vectors are of the highest quality, we undertake...mission of accelerating scientific research. To make sure that adeno-associated viral (AAV) vectors available...all the DNA packaged inside the viral particles (Figure 1). Briefly, packaged DNA is extracted from purified...plasmid #44362. Method validation, limitations, and future plans How did AAV-68544 become contaminated? Well...processed the mixed sample in our pipeline (see Figure 2, sample 2). When we blindly analyzed AAV-68544... the Addgene blog Check out our Viral Vectors Featured Topic Page Subscribe to Viral Vectors Blog Posts...

...antibodies that bind to the spike proteins in cell culture, and inhibit these viruses.  But llama immunization...proteins that may unfold due to camelid high body temperature (37.2 - 39.2°C). The Seeger lab found a way around...protein targets, similar to how antibodies do. The structure of the common antibody is heftier (~150 kDa) and...molecular crevices proteins on the cell surface. Figure 1: Comparison of common antibody, HCab, and nanobody...protocol, which cover 3 naturally-occurring nanobody structures (concave, loop, and convex). Each of these 3 ... to select for optimal sybody candidates. Figure 2: Outline of the process for selection of sybodies...anti-Myc antibodies bound to an ELISA plate to capture Myc-tagged sybodies. Then, the biotinylated target...

...to Our Podcast Interview with Alex Chavez Figure 1: Schematic of native (nuclease-competent) Cas9...of genome editing (Fig. 2 and 3) (5, 3). Figure 2: Gene activation with nuclease-competent Cas9...alterations observed at the target site.   Figure 3: Gene repression with nuclease-competent Cas9... systems. She is also a NASA Fellow studying biosignature preservation in Mars analogue environments. ...proteins for RNA-guided gene regulation and editing." Nature methods 10.11 (2013): 1116-1121. PubMed PMID: 24076762... parameters via a library-on-library approach." Nature methods 12.9 (2015): 823-826. PubMed PMID: 26167643...for genome editing, activation and repression." Nature methods 12.11 (2015): 1051-1054. PubMed PMID: 26344044...

...situations in cells are described below (See Figure 1).   Figure 1: Each problem with dimerizing fluorescent...follow. It's a matter of concentration Most FPs in nature are prone to dimerization (i.e. EGFP) [1, 2] or...together and can wrap the membranes into stacked structures including organized smooth endoplasmic reticulum...state, and an artificially active state due to closure by FP dimerization.   1. Transmembrane fluorescent...if a dimerizing FP is fused to the POI. These structures are large (microns), bright, non-physiological...whorl formation assay, are practical real world measures of dimerization potential that will determine ...GFP-based FRET, with application to intrinsically unstructured proteins. Protein Sci, 2007. 16(7): p. 1429-...

...10hours. Temperature: FPs maturation times and fluorescent intensity can be affected by the temperature. For...no use to you. When using more than one FP, make sure their emission light does not overlap in wavelength...new GFP isolated from the Unagi eel was shown to mature independently of oxygen, making suitble for use...studies (24-30°C). Brightness: Brightness is a measure of how bright is the emission. Brightness is calculated...parameters (e.g. excitation light intensity, pH or temperature). Photostability: Fluorescent molecules gets ...lose the ability to emit light) after prolonged exposure to excitation light. Photostability can be as ...parameters (e.g. excitation light intensity, pH, or temperature). pH Stability: This parameter is important if...

...inhibitors to your culture media prior to and after Cas9 introduction increases HDR, just make sure to remove ...distance. Homology arms and types of donors To make sure your donor molecule is used as the template, you...your Cas9 cuts in the coding region of a gene, make sure that the PAM edit you introduce is a silent mutation...exist as a repair template. To maximize HDR events, ensure cells are actively cycling through the cell cycle..., they will not undergo DNA replication, so make sure you are keeping an eye on those cells! To take this...mediates efficient homology-directed repair and termperature-controlled genome editing. Nat. Com., 8(2024...Resources on the Addgene Blog Check out our CRISPR Featured Topic Page Learn about Non-Homologous End Joining...

...scientific community and their game changing nature. Full disclosure: Zimmer also spends some time on Addgene...Zimmer’s recent book, The State of Science: What the Future Holds and the Scientists Making It Happen, is an...I began my own career over 20 years ago, and I’m sure they were issues long before then. Other areas are...for me. A brief window in time “The most obvious future consequence of the undermining of the scientific...and technology.” This last section of the book, Future Science, describes the author’s thoughts on science... science and summarizing its past, present, and future in under 200 pages is an impressive task to set...Science could be a jumping off point to explore future rabbit holes. For the non-scientists in your life...

...different systems could be combined effectively (3). In Figure 1 for instance, the DBD of the fusion protein shown... interest(POI’s) are fused to TAs and DBDs (see Figure 2a) (4). These fusions are then co-expressed in...DBD-POI fusion (commonly referred to as the “bait”, Figure 2b) cannot activate reporter gene expression on...promoter of the reporter gene to activate expression (Figure 2c). The reporter gene then allows detection of...the HIS3 gene, which is required for histidine manufacture and therefore growth on his-deficient media. ...known to bind serves as a good positive control to ensure that your setup works. The last thing you want ... system to detect protein-protein interactions. Nature. 1989; 340:245-246. PubMed PMID: 2547163. 5. Ozawa...

... Addgene scientists inspect each sample and make sure they have been barcoded with a unique ID number ...number (1D barcode as shown below). This number ensures that every sample can be tracked easily at each step...involves good aseptic technique and controls to ensure that nothing is contaminated. We use filtered pipet...both of these are scanned into our LIMS system to ensure that they match, helping us to avoid mixing up ...glycerol stocks on Fridays. From each overnight culture, we prepare three sets of 2D barcoded tubes. Two...receiving, transforming, and storage process, we ensure that the sample tubes that we use match those of... to help track samples. They will help your lab ensure that sample ID’s are unique, consistently labeled...

...systemic biases which, in the absence of support and structure, prevent science from attracting and keeping diverse... diverse talent in science related careers. Failure to strengthen the talent pipeline sets the world up...to be successful after their training.   Figure 1: Professional Development Hub Workshop Attendees... with such a group dedicated to providing the structure and know-how to integrate career development in...areas of the scientific training and employment infrastructure. A Stakeholder Workshop at Janelia Research...2019 solidified the project and the findings were captured in this just released report “Enhancing Dissemination...attracting and launching science talent we must ensure that career skills training is a required and integral...

...included a glossary at the end of this post! Figure 1: Base transitions are edits between the purine...proof of concept for further development. Figure 2: Mechanisms of deaminase-based adenine transversion...for base editor development going forward. Figure 3: Mechanism of gGBE. Created with BioRender.com...•G base editing in mammalian cells and embryos. Nature Biotechnology, 42(4), 638–650. https://doi.org/...editor by engineered human uracil DNA glycosylase. Nature Communications, 15(1), 4897. https://doi.org/10.1038... editor with an N-methylpurine DNA glycosylase. Nature Biotechnology, 41(8), 1080–1084. https://doi.org...efficient T-to-G and C-to-G editing in mammalian cells. Nature Biotechnology, 42(10), 1538–1547. https://doi.org...

...Genome-scale measurement of off-target activity using Cas9 toxicity in high-throughput screens." Nature communications...this holds true in genome-wide screens.   Figure 1: Summary of the advantages of the new approach...effects of guide expression and dsDNA breaks. Figure 2: Non-targeting vs. safe-targeting guides. The...dsDNA breaks caused by CRISPR. See supplemental figure 6 for more details. Safe-targeting guides also ...of off-target cleavage by CRISPR-Cas nucleases." Nature biotechnology 33.2 (2015): 187. Pubmed PMID: 25513782...nuclease specificity using truncated guide RNAs." Nature biotechnology 32.3 (2014): 279. Pubmed PMID: 24463574... Other Resources Watch Dr. Michael Bassik’s lecture on “Multiplexing with CRISPR Screens”    ...

... everyone has their ideas heard.  So how can we assure that all participants feel comfortable sharing ...to encourage dissenting opinions is to foster a culture of inclusivity. Work with and value people who ...your lab/company/team is still working towards a culture of encouraging dissent, the next tip may be particularly...feel they can share opposing opinions as well. I am sure we have all experienced a meeting where one person...may not have the highest position or the longest tenure, but don’t let that stop you from speaking up.  ...them. If you can, set aside time to prepare for future challenges. This doesn’t have to be time-consuming...minutes every month dedicated to thinking about the future will improve your ability to innovate. (Finkelstein...

...mCherry is constitutively expressed. Cells are then cultured and FACS sorted. Image from Mateo Sanchez and ...-7 Optimizing fluorescent tools for labeling structures and compartments in mammalian cells By Angela...fluorescent proteins are often used to label  specific structures, compartments, or specific localization of biomolecules...provide misleading information on where exactly a structure or protein is located within a cell. The Goedhart...encoded fluorescent markers for labeling specific structures within cells. HeLa cells were transfected...and mScarlet-I for labeling a list of specific structures within cells. For example, to improve nuclear...microtubules. Find these fluorescent mammalian cell structure markers plasmids at Addgene! Chertkova, AO, et...

...tools and infrastructure in use at research universities not only today, but also in the future. Reproducibility...choosing an ELN for your research, be sure to consider how its features do and don’t support reproducibility...without access to them, the record of research captured in the ELN is incomplete. Thus, to support reproducibility...for discussion and review. It’s also possible to capture Slack conversations and import them into RSpace...and workflows that went into it. The ability to capture the conversations and associate them with a particular...ability to deposit data that has already been structured in folders or notebooks in the ELN, without having...

...the success of a drug’s clinical and commercial future, and yet are incredibly difficult to find solutions...The consultants who enjoy their jobs most, get pleasure from taking up such complex challenges, quickly...parts of the job? With fast turnover of projects, pressure to maintain consistently high levels of performance...consulting can sometimes be challenging. The fast paced nature of projects often means working long hours both...using lessons from previous cases to better staff future teams. As with any highly collaborative work place... scientific background, training in reviewing literature, and critical analyses skills were applicable... and equity research firms, biotech start-ups, venture capital firms, and more. Essentially any role in...

...GFPs The availability of the three dimensional structure of GFP, its brighter mutant S65T-GFP, and the ...bfloGFPc1. The plasmids used for determining the structures are now available from Addgene - bfloGFPa1 and...Mitochondrial health, transport and turnover are important features to be monitored to study mitochondrial dysfunction...dysfunction. Easy-to-use tools to monitor these features were lacking until Roberta Gottlieb and Zhen Yan labs...pTRE-Tight-MitoTimer) to show its usefulness in cell culture to report changes in mitochondrial turnover and...against common tumor markers to enhance cancer cell capture. Fierer et al., PNAS 2014 Apr 1;111(13):E1176...molecules and exceed a physiologically relevant exposure in intensity and/or duration. Both of these strategies...

...something doesn’t work, it’s not a failure. It’s an education.   Figure 4: Zenodo page showing the IBEX...reagents that work for our experiments!)     Figure 1: The IBEX Imaging Community front page. That...both their successes (recommended reagents) and failures (not recommended reagents) along with information... directly from the Zenodo dataset.     Figure 2: Screenshot showing reagent entries with associated...discussion with others in the IBEX community.   Figure 3: Screenshot showing recent topics in the IBEX...method for high-content imaging of diverse tissues. Nature Protocols, 17(2), Article 2. https://doi.org/10.1038...

...here and no viral progeny are produced (Figure 1).  Figure 1: Comparison of the life cycle of a lentiviral...recombination or non-homologous end joining (see Figure 2).  Figure 2: Schematic representation of integration...cell but cannot integrate it into the host genome (Figure 1). IDLVs were first discovered by researchers ...continuously expressed (Fu et al., 2013). Using IDLVs ensures transient expression without the risks associated...titering IDLVs, there is no integrated piece to measure! Instead, two commonly employed methods for titering...induced by CRISPR-Cas nucleases in human cells. Nature Biotechnology, 31(9), 822–826. https://doi.org/...

...Spinach2 reveals the dynamic nature of trinucleotide repeat–containing RNA." Nature methods 10.12 (2013): 1219...generated allows for qualitative and quantitative measurement of processes including RNA movement by tagging...many structural properties with DFHBI, but its structure allows for greater contact with its RNA aptamer...in the orange or red channel, depending on the structure of the TO derivative (Dolgosheina et al., 2014...imaging small non-coding RNAs in mammalian cells." Nature communications 9.1 (2018): 656. PubMed PMID: 29440634...transcription using a photostable RNA–fluorophore complex." Nature chemical biology 13.11 (2017): 1187. PubMed PMID...efficient RNA mimics of green fluorescent protein." Nature structural & molecular biology 21.8 (2014): 658...

...insert into your vector of choice as shown in the figure below. To start, you need to have DNA fragments...enzymes is that they can all work at the same temperature, so the entire reaction takes an hour or less...an overlap of 15-40 bp, with a primer melting temperature greater than 48℃. Both Snapgene and NEB have ...fragments have stable single stranded DNA secondary structure, such as a hairpin or a stem loop (as might be...overlapping region between fragments also better ensures correct assembly order of the fragments as compared...’ exonuclease instead of using the exonuclease feature of T4 DNA polymerase, which must be controlled ... these kits may come at a high price, their manufacturers tout great efficiency and low time commitments...

...through the La Vida Scholars summer program. I was unsure whether or not I wanted to major in biochemistry..., who let me know in March that I successfully secured an internship at Addgene! I was eager to accept...took into consideration just how busy I was and ensured that my decision deadline would be extended. I ...reached out to Amy with exciting news. I managed to secure a virtual summer program, teaching me the basics...each intern to complete and present on.    Figure 1: Addgene's summer interns presenting their capstone...crunch and knew that if we were to restart the procedure we would not have enough time. During the following...from the electrophoresis, my manager and I were unsure if there were any successful clones because the...

...model and a source of sdAbs (Figure 2) (Xu, et al., 2021).      Figure 2: Genetically modified mice...found similar antibodies in llamas and alpacas (Figure 1). At the time, researchers were already on a ...nanobodies (Arbabi-Ghahroudi, 2017)!      Figure 1: Comparison of a heavy-chain only antibody and... for in vivo experiments, due to their simple structure    sdAbs in research These advantages have contributed...Single-Domain Antibodies: Historical Perspective and Future Outlook. Front Immunol 8:1589. https://doi.org/...mice and llamas neutralize SARS-CoV-2 variants. Nature 595:278–282. https://doi.org/10.1038/s41586-021...

...constant, or Fc, domain. Sure, we all know that the Fc domain provides structure, determines isotypes, and...does! While the Fc domain’s functions, besides structure and isotype determination, don’t generally affect...sorted into three main effector functions.  Figure 1: Fc effector functions in an immune response ...antibody-dependent cellular phagocytosis (ADCP). Figure adapted from van Erp, et al., 2019.    Antibody-dependent...description with the Fc domain as only providing structure and isotype determination, remember that it can...Ig Constant Region Effects on Variable Region Structure and Function. Frontiers in Microbiology, 7. https...

... a couple of lectures in the undergraduate pharmacology course, like one or two lectures a year. And then.... And make sure to subscribe to the Career Channel of the blog so you don’t miss the future posts in this... the first time. I walk[ed them] through their lecture, giving them advice, [and helped] proctor exams...how to design test questions, and how to design lectures. I really built a course from the ground up.”  ...careers while in grad school And just for good measure, here’s a few other posts about developing transferable...

...techniques with higher efficiency and simpler procedures have been developed. Some of these include, TA...annealed and ligated in vivo. Detailed FastCloning procedure To start the FastCloning process, the insert and...and the resultant products of the reaction in the figure from Chaokun et al., 2011 to the right. After PCR...isolated from methylation competent E. coli for this procedure to work properly. Directly transform chemically...chemically competent cells with the digested mixture. There is no need for further purification before transformation...vector + insert). You should screen 3-4 colonies to ensure that you find the correct product. Once you find...have a better understanding of the step by step procedure of FastCloning, here are some tips for high efficiency...

...carte." Nature Reviews Genetics 12, no. 4 (2011): 231-42. PubMed PMID: 21339765. Methods figures were adapted...purify reprogramming proteins. Table 1: Key Features of Different Methods for Generating iPSCs. One...even after many passages. Ban et al developed a temperature sensitive Sendai virus which is removed by culturing...endogenous pluripotency genes (i.e. Oct4) are other measures of reprogramming. If a retrovirus was used, then...field of induced pluripotency: Recent progress and future challenges." Journal of Cellular Physiology 228...pluripotent mouse stem cells by the piggyBac transposon." Nature Methods 6, no. 5 (2009): 363-69. PubMed PMID: 19337237...minicircle vector for deriving human iPS cells." Nature Methods 7, no. 3 (2010): 197-99. PubMed PMID: 20139967...

...been developed around how they replicate (Figure 2). Figure 2: Baltimore replication classes. Image credit...molecular biology tools, a very useful trait. Virus structure While all viruses have a genome inside a protein... with an envelope are called enveloped viruses (Figure 1). Like bacteria, only a tiny fraction of viruses...viruses are pathogenic (Balloux & van Dorp, 2017). Figure 1: A non-enveloped virus (left) and an enveloped...packaged in separate plasmids and expressed via cells cultured with the vectors. This allows the viral vectors...of Viral Vectors 101 posts about each type, so be sure to check our blog, or our Viral Vectors 101 eBook...