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Exploratory data analysis and common statistical assumptions in biology

Sonnenburg, his wife Erica, and the graduate student Samuel Smits confirmed this idea in a recent experiment. The researchers started with mice that had been raised in sterile bubbles and then loaded with identical collections of gut microbes. They then fed these mice a high-fiber diet, before randomly switching half of them to low-fiber chow for seven weeks. Predictably, the fall in fiber caused upheavals in the rodents' guts. In the low-fiber group, the numbers of 60 percent of the local microbe species fell dramatically, and some remained low even after the mice returned to high-fiber meals. Those seven low-fiber weeks left lingering scars on the animals' microbiomes.

In the blood of a survivor of the recent Ebola outbreak, a team of researchers has discovered a number of antibodies that seem to successfully combat the deadly virus in mice. The findings, published in the journal Science, may help point scientists in the right direction for developing a vaccine that could protect against the disease.

Stress is implicated in increased tumor progression risk and poor survival in cancer patients. A number of recent studies have linked these effects to the promotion of tumor cell dissemination through the bloodstream via stress-induced pathways. Now, a mouse study led by researchers in Australia has revealed the mechanisms by which stress modulates cancer's spread through another transport network open to tumor cells-the lymphatic system.

I'd come that afternoon to witness what has become a rarity: the non-forensic medical autopsy. "Autopsy" means to see for oneself, and that is exactly what doctors once did. Fifty years ago we performed autopsies on roughly half of patients who died in hospitals. Today, the number of autopsies has dwindled to less than 10 percent, with next to none in nonacademic hospitals.

You will learn about "Dalton's Atomic Theory" in this video. John Dalton was an English chemist who is very well known today for his work in the development of atomic theory. Let us learn the postulates of Dalton's atomic theory. All matter, whether an element, a compound or a mixture are made up of very tiny particles called atoms. All atoms of a given element are identical in size, mass and chemical properties. Atoms of different elements differ in size, mass and chemical properties. Atoms are indivisible particles which can neither be created nor destroyed in a chemical reaction. Atoms combine together in fixed whole number ratios to form compounds. In a chemical reaction, atoms only get rearranged. An atom of an element does not change into the atom of another element.

The box plot (a.k.a. box and whisker diagram) is a standardized way of displaying the distribution of data based on the five number summary: minimum, first quartile, median, third quartile, and maximum. In the simplest box plot the central rectangle spans the first quartile to the third quartile (the interquartile range or IQR). A segment inside the rectangle shows the median and "whiskers" above and below the box show the locations of the minimum and maximum.

Over recent decades, scientists have made various discoveries about DNA methylation and how vital it is to a number of cellular processes such as embryonic development, X-chromosome inactivation, genomic imprinting, gene suppression, carcinogenesis and chromosome stability. Researchers have linked abnormal DNA methylation to several adverse outcomes, including human diseases.

This case study provides an overview of the seminal experimental work that led to the discovery of DNA structure and the confirmation of the semi-conservative model of DNA replication. By guiding students through a chronological series of historic experiments and discussing some of the collaborations and controversies involved in the original research, students learn about the history and nature of science in addition to several important biological concepts. A number of recommended videos, including one created by the author, enable instructors to use the "flipped-classroom" mode of instruction according to which students read primary literature and watch videos on their own before group discussions and activities. The case study was developed for use in an introductory undergraduate biology course, and would also be appropriate for use in a high school biology course. Some prior knowledge or instruction may be required, depending on the level and learning objectives of the course.

This flipped case study tells the story of Joyce, a biology student who notices the development of some unusual symptoms (foot slapping and slurred speech) in her mother. In an effort to understand the cause, Joyce views a documentary-style trigger video (created by the case author) that suggests to Joyce that her mom may in fact have amyotrophic lateral sclerosis or ALS. The rest of the case walks Joyce through understanding how normal neurons compare to neurons in ALS patients and how that might affect muscle function. The case explores the link between genes, particularly SOD-1, to the formation of malformed proteins and its potential role in the development of ALS. The case concludes with a discussion of drug development and highlights the timeline and costs associated with drug discovery as Joyce becomes concerned about the lack of drugs in the pipeline for ALS, which her mother is ultimately diagnosed with. The case is appropriate for a number of classes including general biology, biotechnology, anatomy and physiology, upper level-cell biology, or any human health and disease-related course.

The theory of evolution by natural selection is simple, elegant, and profound. Yet, a large number of undergraduate students including biology majors, medical students, and pre-service science teachers maintain a large set of misconceptions that interfere with a solid understanding of the process of natural selection. It is also well known that lecturing is an insufficient strategy to help students confront and correct these misconceptions. This activity uses the evolution of coat color in oldfield mice (Peromyscus polionotus) as the basis of a case study in which students investigate the role of variation, heritability, and selection in the evolution of a trait. Students examine graphs, data, and excerpts from a series of papers that have been published about this system over the last 100 years. The content is delivered as an interrupted case and encourages peer-to-peer teaching and interaction. The case is appropriate for use in non-major, introductory, or advanced biology courses.

The human large intestine (colon), in healthy individuals, has extremely low oxygen concentrations, and over 90% of its microbiota are strict anaerobes. Researchers taking metagenomic fecal microbiota surveys of adult Europeans could assign about 0.8% of the genes in their dataset to archaea [9], and similar numbers (0.2%-0.3%) were reported for Amerindians and Malwaians [10], while North Americans had much lower fractions (<0.05%).

As you read the chapters in Stiff, attach a post-it note to pages where you highlight something interesting. You should have 4-10 Post-It's per chapter, use the following symbol guide to create your notes. Stiff has 12 chapters, you are only required to map (Post-It) 8 of those chapters. You are welcome to read them all, of course, but you can also choose to focus on chapters that interest you the most or skip those you do not find interesting. You may wish to skim the chapters or browse the table of contents. Each Post-It will contain three items 1. Symbol (see chart) 2. Page and paragraph number 3. Content

This PowerPoint-driven, flipped case study begins with a short video about a woman suffering from cystic fibrosis (CF) in the 1970s, a friend of the lead author's, whom she met in college and who died in her twenties. Hooked by this personal story, students then delve into the genetics and biology of cystic fibrosis as they learn about the difference between dominant and recessive genes, make Punnett squares that depict various types of inheritance, distinguish between probability and actual numbers, differentiate types of mutations, and learn about the opportunistic infections that CF patients often succumb to.  Students conclude the case by watching two additional videos on chest compression machines and the contemporary life expectancy of patients with CF.  In addition to the scientific content presented in the case, it is hoped that students will empathize with, and be motivated by, the young people presented in the videos as they struggle with a very real, incurable disease deeply rooted in genetics.

Scientists have discovered that the newly found Tapanuli orangutan of Sumatra is more closely related to its cousins in Borneo than it is to its fellow Sumatran apes. The Tapanuli population numbers only around 800 individuals.

Squirrels are frequent and beloved residents of college campuses throughout the United States, but oftentimes less welcomed by campus maintenance officials who report squirrels nesting in buildings, interfering with airflow from heating and cooling units, and destroying gutters. In this laboratory case, students act as members of a fictitious "squirrel task force" appointed by their campus administrators to provide recommendations for how to manage their school's squirrel population.  Students work in groups to assess the habitat suitability of their campus for squirrels by identifying and measuring trees that provide seasonal food for squirrels, and by identifying desirable hunting perches for common squirrel predators.  Students conduct squirrel surveys in designated campus zones to calculate the number of squirrels per acre on their campus and compare it with mean squirrel densities reported in forested areas and at a rival institution.  Students then compile and synthesize class data to provide management recommendations for university maintenance officials for either increasing or decreasing campus squirrel populations. Originally developed for an undergraduate wildlife biology course, the case could also be used in a lower-division biology or environmental studies course.

For the first time in modern history, the world's population is expected to virtually stop growing by the end of this century, due in large part to falling global fertility rates, according to a Pew Research Center analysis of new data from the United Nations. By 2100, the world's population is projected to reach approximately 10.9 billion, with annual growth of less than 0.1% - a steep decline from the current rate. Between 1950 and today, the world's population grew between 1% and 2% each year, with the number of people rising from 2.5 billion to more than 7.7 billion.

n. As such, this set of Essential Elements addresses a small number of science standards, representing a breadth, but not depth, of coverage across the entire standards framework. The purpose of the DLM Essential Elements is to build a bridge from the content in the general education science framework to academic expectations for students with the most significant cognitive disabilities. This version of the Essential Elements will provide content for science assessments for at least the next two years. The DLM Science Consortium intends to develop a learning map based on research about how students learn science content and engage in scientific and engineering practices in the next phase of the project. Revisions will be made when the science map is complete, at which time we anticipate the EEs will be aligned to the map with revisions and additions as appropriate.

That's the premise behind XPRIZE Feed The Next Billion, a $15 million competition incentivizing teams around the globe to produce chicken breast or fish filet alternatives that outperform conventional chicken and fish in a number of areas - from sustainability to nutrition to animal welfare, as well as taste and texture. To achieve that, teams are leaning into two methods: cultivated meat and plant-based meat alternatives. The multi-year competition is underway right now, and could provide us with the breakthrough we need to change how we eat, for good.

Published today (17:00BST, 03/06/2015) in the journal Neuron, their work presents strong evidence that disruption of a delicate chemical balance in the brain is heavily implicated in the disorder. In the largest ever study of its kind, the team found that disease-linked mutations disrupt specific sets of genes contributing to excitatory and inhibitory signalling, the balance of which plays a crucial role in healthy brain development and function.