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Reporting on a small preliminary study, Johns Hopkins researchers say a simple blood test based on detection of tiny epigenetic alterations may reveal the earliest signs of pancreatic cancer, a disease that is nearly always fatal because it isn't usually discovered until it has spread to other parts of the body.

In 1977, a University of Oxford statistician named Richard Peto pointed out a simple yet puzzling biological fact: We humans should have a lot more cancer than mice, but we don't. Dr. Peto's argument was beguilingly simple. Every time a cell divides, there's a small chance it will gain a mutation that speeds its growth. Cells that accumulate several of these mutations may become cancerous. The bigger an animal is, the more cells it has, and the longer an animal lives, the more times its cells divide. We humans undergo about 10,000 times as many cell divisions as mice - and thus should be far more likely to get cancer.

One of these days, there could well be a simple blood test that can help diagnose and track cancers. We aren't there yet, but a burst of research in this area shows we are getting a lot closer.

A quick and simple blood test could soon diagnose which cancer a patient has and how advanced the disease is, scientists said.

Although rabies still causes thousands of deaths globally every year, it has essentially been eradicated from most industrialized countries. Part of the success story is due to an unusual project undertaken by the Swiss prompted by a series of large outbreaks in the 1970s: the large-scale vaccination of wild foxes to stop the epidemic. In this directed case study, students use an easily accessible MS Excel-based model to understand key epidemiological parameters of rabies outbreaks in wild foxes. The simple model allows students also to predict what proportion of foxes needs to be vaccinated to eradicate the virus from the population. The case fits into both ecological and microbiological (epidemiological) courses and offers opportunities to explore zoonotic diseases and "One Health" questions. The mathematical basis of the differential equations in the models is explained, although prior knowledge of calculus is not essential. A key learning outcome is the critical understanding of both the power and limitations of simple epidemiological models. This case was written for an online course but could also be used as a face-to-face activity if students have access to computers in class.

The idea of a general, quick and simple blood test for a diverse range of cancers just came closer to reality with news of a new study published in Nature Medicine.

In a paper this week in Science, Vogelstein and Cristian Tomasetti, who joined the biostatistics department at Hopkins in 2013, put forth a mathematical formula to explain the genesis of cancer. Here's how it works: Take the number of cells in an organ, identify what percentage of them are long-lived stem cells, and determine how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Thus, Tomasetti and Vogelstein reasoned, the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.

" A brief visual task can predict IQ, according to a new study. This surprisingly simple exercise measures the brain's unconscious ability to filter out visual movement. The study shows that individuals whose brains are better at automatically suppressing background motion perform better on standard measures of intelligence. The test is the first purely sensory assessment to be strongly correlated with IQ and may provide a non-verbal and culturally unbiased tool for scientists seeking to understand neural processes associated with general intelligence."

4:0o video Photosynthesis is an essential part of the exchange between humans and plants. Amanda Ooten walks us through the process of photosynthesis, also discussing the relationship between photosynthesis and carbohydrates, starch, and fiber -- and how the air we breathe is related to the food we ingest.

8:13 One of the greatest mysteries is not whether ghosts are real or if there's alien life. The mystery is us. Here are some simple things our body does that science still can't figure out.

Darwin's theory of biological evolution helps us understand how simple life forms can give rise to complex lifeforms, but how did the first reproducing creatures come about? The origin of life needs its own explanation.

In a creative stroke inspired by Hollywood wizardry, scientists from Harvard Medical School and Technion-Israel Institute of Technology have designed a simple way to observe how bacteria move as they become impervious to drugs. The experiments, described in the Sept. 9 issue of Science, are thought to provide the first large-scale glimpse of the maneuvers of bacteria as they encounter increasingly higher doses of antibiotics and adapt to survive - and thrive - in them.

From something as small and complex as a chromosome to something as seemingly simple as the weather, sex determination systems vary significantly across the animal kingdom. Biologist and teacher Aaron Reedy shows us the amazing differences between species when it comes to determination of gender.

In 1674, Antonie van Leeuwenhoek looked at a drop of lake water through his homemade microscope and discovered an invisible world that no one knew existed. His work inspired countless microbiology researchers, including HHMI investigator Bonnie Bassler, one of the narrators of this animated feature. Leeuwenhoek was a haberdasher and city official in Delft, The Netherlands. He started making simple microscopes and using them to observe the world around him. He was the first to discover bacteria, protists, sperm cells, blood cells, rotifers, and much more. 

Many of these labs allow students to test multiple variables. Caution: the journal and data entry sections of the simulations do not work, so you probably will want to arrange for students to write these on their own pages. Many of these labs are useful to substitute for activities in the class that are too costly, dangerous, or time consuming. I have assigned grades to some that I've explored in detail. Grades are based on interactivity, useability, and overall value of the exploration. Many of these can be used as simple class demonstrations, whereas others are more useful for having students explore and change variables.

Are viruses life forms or not? Scientists have been fighting about it for years, and Anthony has more on the latest wrinkle in this seemingly simple yet age-old debate.

The Nib" recently posted a cartoon that breaks down vaccine history, hysteria and necessity all in one easy-to-read and understand cartoon.

In this lesson, students explore the fundamental mathematical concepts underlying the spread of contagious diseases. Using a simple exponential model, students compare and contrast the effects of different transmission rates on a population and develop an understanding of the nature and characteristics of exponential growth. Students can then compare their projections with actual Ebola data from West Africa, to create context for analyzing the strengths and limitations of this simplified model.

Answer five simple questions about a bird you are trying to identify and Merlin will come up with a list of possible matches. Merlin offers quick identification help for beginning and intermediate bird watchers to learn about North America's most common birds!

We're taking a systems approach to learning about the Earth using real scientific data. Our goal is to design easy-to-use curriculum activities and simple, intuitive computer interfaces for accessing online data. It's all part of a NOAA-supported effort called the NODE Project.