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Very high-throughput sequencing technologies need to be matched by high-throughput functional studies if we are to make full use of the current explosion in genome sequences. We have generated a very large bacterial mutant pool, consisting of an estimated 1.1 million transposon mutants and we have used genomic DNA from this mutant pool, and Illumina nucleotide sequencing to prime from the transposon and sequence into the adjacent target DNA. With this method, which we have called TraDIS (transposon directed insertion-site sequencing), we have been able to map 370,000 unique transposon insertion sites to the Salmonella enterica serovar Typhi chromosome. The unprecedented density and resolution of mapped insertion sites, an average of one every 13 base pairs, has allowed us to assay simultaneously every gene in the genome for essentiality and generate a genome-wide list of candidate essential genes. In addition, the semiquantitative nature of the assay allowed us to identify genes that are advantageous and those that are disadvantageous for growth under standard laboratory conditions. Comparison of the mutant pool following growth in the presence or absence of ox bile enabled every gene to be assayed for its contribution toward bile tolerance, a trait required of any enteric bacterium and for carriage of S. Typhi in the gall bladder. This screen validated our hypothesis that we can simultaneously assay every gene in the genome to identify niche-specific essential genes.
Glacier mass loss affects sea level rise, water resources, and natural hazards. We present global glacier projections, excluding the ice sheets, for shared socioeconomic pathways calibrated with data for each glacier. Glaciers are projected to lose 26 ± 6% (+1.5°C) to 41 ± 11% (+4°C) of their mass by 2100, relative to 2015, for global temperature change scenarios. This corresponds to 90 ± 26 to 154 ± 44 millimeters sea level equivalent and will cause 49 ± 9 to 83 ± 7% of glaciers to disappear. Mass loss is linearly related to temperature increase and thus reductions in temperature increase reduce mass loss. Based on climate pledges from the Conference of the Parties (COP26), global mean temperature is projected to increase by +2.7°C, which would lead to a sea level contribution of 115 ± 40 millimeters and cause widespread deglaciation in most mid-latitude regions by 2100.
We present a measure-theoretic condition for a property to hold "almost everywhere" on an infinite-dimensional vector space, with particular emphasis on function spaces such as <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C Superscript k"> <mml:semantics> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mi>C</mml:mi> <mml:mi>k</mml:mi> </mml:msup> </mml:mrow> <mml:annotation encoding="application/x-tex">{C^k}</mml:annotation> </mml:semantics> </mml:math> </inline-formula> and <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper L Superscript p"> <mml:semantics> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mi>L</mml:mi> <mml:mi>p</mml:mi> </mml:msup> </mml:mrow> <mml:annotation encoding="application/x-tex">{L^p}</mml:annotation> </mml:semantics> </mml:math> </inline-formula> . Like the concept of "Lebesgue almost every" on finite-dimensional spaces, our notion of "prevalence" is translation invariant. Instead of using a specific measure on the entire space, we define prevalence in terms of the class of all probability measures with compact support. Prevalence is a more appropriate condition than the topological concepts of "open and dense" or "generic" when one desires a probabilistic result on the likelihood of a given property on a function space. We give several examples of properties which hold "almost everywhere" in the sense of prevalence. For instance, we prove that almost every <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C Superscript 1"> <mml:semantics> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mi>C</mml:mi> <mml:mn>1</mml:mn> </mml:msup> </mml:mrow> <mml:annotation encoding="application/x-tex">{C^1}</mml:annotation> </mml:semantics> </mml:math> </inline-formula> map on <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="double-struck upper R Superscript n"> <mml:semantics> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="double-struck">R</mml:mi> </mml:mrow> <mml:mi>n</mml:mi> </mml:msup> </mml:mrow> <mml:annotation encoding="application/x-tex">{\mathbb {R}^n}</mml:annotation> </mml:semantics> </mml:math> </inline-formula> has the property that all of its periodic orbits are hyperbolic.
Ensuring that all students achieve the same high standard of learning would be much easier if you could quickly and easily customize lesson plans and curriculum materials to each student's needs, interests, and skills level. Here's a book that explains how to make that ideal a reality. Explore the concept of Universal Design for Learning and how it can help you meet standards while you address the unique needs of each student. Drawing from brain research and the power of digital technology, the authors explain how to: Set appropriate goals for every student. Choose the teaching methods and materials that give every student optimum instructional support. Ensure the fair and accurate assessment of every student's progress. A school case study, a set of templates, and links to online resources get you started in applying the concepts to your classroom. A companion website offers interactive experiences, classroom videos, lessons, online discussions, interviews with experts, student case stories, resource links, and more in-depth information.
The World Health Report 2005 – Make Every Mother and Child Count, says that this year almost 11 million children under five years of age will die from causes that are largely preventable. Among them are 4 million babies who will not survive the first month of life. At the same time, more than half a million women will die in pregnancy, childbirth or soon after. The report says that reducing this toll in line with the Millennium Development Goals depends largely on every mother and every child having the right to access to health care from pregnancy through childbirth, the neonatal period and childhood.
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Floating-point arithmetic is considered as esoteric subject by many people. This is rather surprising, because floating-point is ubiquitous in computer systems: Almost every language has a floating-point datatype; computers from PCs to supercomputers have floating-point accelerators; most compilers will be called upon to compile floating-point algorithms from time to time; and virtually every operating system must respond to floating-point exceptions such as overflow. This paper presents a tutorial on the aspects of floating-point that have a direct impact on designers of computer systems. It begins with background on floating-point representation and rounding error, continues with a discussion of the IEEE floating point standard, and concludes with examples of how computer system builders can better support floating point.
In 1928, U.S. presidential candidate Herbert Hoover promised growing prosperity represented by “a chicken in every pot and two cars in every garage.” We now find ourselves at a point in history wondering if and when the power for those cars will come from fuel cells instead of internal combustion engines.
Transgender and gender non-conforming people face rampant discrimination in every area of life: education, employment, family life, public accommodations, housing, health, police and jails, and ID documents. This data is so shocking that it will change the way you think about transgender people and it should change the way you advocate. The National Transgender Discrimination Survey was conducted by the National Gay and Lesbian Task Force and the National Center for Transgender Equality.
1. Looking at Language Learning Strategies 2. Direct Strategies for Dealing with Language 3. Applying Direct Strategies to the Four Language Skills 4. Indirect Strategies for General Management of Learning 5. Applying Indirect Strategies to the Four Language Skills 6. Language Learning Strategy Assessment and Training 7. Networking at Home and Abroad
abstract This paper looks at the workings of ongoing primary sensemaking and sensegiving micro‐practices by which middle managers interpret and sell strategic change at the organizational interface. Through middle managers’ routines and conversations related to the implementation of a strategic change in a top‐of‐the‐line clothing company, the article shows how they contribute to renewing links with stakeholders, in particular clientele, by drawing on their tacit knowledge. Interpretative analysis of these routines and conversations highlights four micro‐practices of strategic sensemaking and sensegiving: translating the orientation, overcoding the strategy, disciplining the client, and justifying the change. The paper outlines a practice perspective of sensemaking and sensegiving. It ends by suggesting the necessity of looking at middle managers’ role as interpreters and sellers of strategic change at the micro level for a better understanding of their contribution in sustaining competitive advantage through their everyday activities.
The ubiquity of AI in society means the time is ripe to consider what educated 21st century digital citizens should know about this subject. In May 2018, the Association for the Advancement of Artificial Intelligence (AAAI) and the Computer Science Teachers Association (CSTA) formed a joint working group to develop national guidelines for teaching AI to K-12 students. Inspired by CSTA's national standards for K-12 computing education, the AI for K-12 guidelines will define what students in each grade band should know about artificial intelligence, machine learning, and robotics. The AI for K-12 working group is also creating an online resource directory where teachers can find AI- related videos, demos, software, and activity descriptions they can incorporate into their lesson plans. This blue sky talk invites the AI research community to reflect on the big ideas in AI that every K-12 student should know, and how we should communicate with the public about advances in AI and their future impact on society. It is a call to action for more AI researchers to become AI educators, creating resources that help teachers and students understand our work.
Microbial community analysis via high-throughput sequencing of amplified 16S rRNA genes is an essential microbiology tool. We found the popular primer pair 515F (515F-C) and 806R greatly underestimated (e.g. SAR11) or overestimated (e.g. Gammaproteobacteria) common marine taxa. We evaluated marine samples and mock communities (containing 11 or 27 marine 16S clones), showing alternative primers 515F-Y (5'-GTGYCAGCMGCCGCGGTAA) and 926R (5'-CCGYCAATTYMTTTRAGTTT) yield more accurate estimates of mock community abundances, produce longer amplicons that can differentiate taxa unresolvable with 515F-C/806R, and amplify eukaryotic 18S rRNA. Mock communities amplified with 515F-Y/926R yielded closer observed community composition versus expected (r(2) = 0.95) compared with 515F-Y/806R (r(2) ∼ 0.5). Unexpectedly, biases with 515F-Y/806R against SAR11 in field samples (∼4-10-fold) were stronger than in mock communities (∼2-fold). Correcting a mismatch to Thaumarchaea in the 515F-C increased their apparent abundance in field samples, but not as much as using 926R rather than 806R. With plankton samples rich in eukaryotic DNA (> 1 μm size fraction), 18S sequences averaged ∼17% of all sequences. A single mismatch can strongly bias amplification, but even perfectly matched primers can exhibit preferential amplification. We show that beyond in silico predictions, testing with mock communities and field samples is important in primer selection.
It started with a simple observation: students need their teachers present to answer questions or to provide help if they get stuck on an assignment; they don't need their teachers present to listen to a lecture or review content. From there, Jonathan Bergmann and Aaron Sams began the flipped classroom-students watched recorded lectures for homework and completed their assignments, labs, and tests in class with their teacher available. What Bergmann and Sams found was that their students demonstrated a deeper understanding of the material than ever before. This is the authors story, and they're confident it can be yours too. Learn what a flipped classroom is and why it works and get the information you need to flip a classroom. You'll also learn the flipped mastery model, where students learn at their own pace-furthering opportunities for personalised education. This simple concept is easily replicable in any classroom, doesn't cost much to implement, and helps foster self-directed learning. Once you flip, you wont want to go back! The International Society for Technology in Education (ISTE) is the trusted source for professional development, knowledge generation, advocacy and leadership for innovation. ISTE is the premier membership association for educators and education leaders engaged in improving teaching and learning by advancing the effective use of technology in PK-12 and teacher education. Home of the National Educational Technology Standards (NETS), the Centre for Applied Research in Educational Technology (CARET), and ISTE's annual conference (formerly known as the National Educational Computing Conference, or NECC), ISTE represents more than 100,000 professionals worldwide. We support our members with information, networking opportunities, and guidance as they face the challenge of transforming education.
Climate adaptation has become a pressing issue. Yet little attention has been paid to the consequences of adaptation policies and practices for sustainability. Recognition that not every adaptation to climate change is a good one has drawn attention to the need for sustainable adaptation strategies and measures that contribute to social justice and environmental integrity. This article presents four normative principles to guide responses to climate change and illustrates the significance of the ‘sustainable adaptation’ concept through case studies from diverse contexts. The principles are: first, recognize the context for vulnerability, including multiple stressors; second, acknowledge that differing values and interests affect adaptation outcomes; third, integrate local knowledge into adaptation responses; and fourth, consider potential feedbacks between local and global processes. We argue that fundamental societal transformations are required in order to achieve sustainable development pathways and avoid adaptation funding going into efforts that exacerbate vulnerability and contribute to rising emissions. Despite numerous challenges involved in achieving such change, we suggest that sustainable adaptation practices have the potential to address some of the shortcomings of conventional social and economic development pathways.
Future economic growth lies in the value of experiences and transformations--good and services are no longer enough. We are on the threshold, say authors Pine and Gilmore, of the Experience Economy, a new economic era in which all businesses must orchestrate memorable events for their customers. The Experience Economy offers a creative, highly original, and yet eminently practical strategy for companies to script and stage the experiences that will transform the value of what they produce. From America Online to Walt Disney, the authors draw from a rich and varied mix of examples that showcase businesses in the midst of creating personal experiences for both consumers and businesses. The authors urge managers to look beyond traditional pricing factors like time and cost, and consider charging for the value of the transformation that an experience offers. Goods and services, say Pine and Gilmore, are no longer enough. Experiences and transformations are the basis for future economic growth, and The Experience Economy is the script from which managers can begin to direct their own transformations.
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