Two-Career Chaos: A Look in the Rearview Mirror

Can we really have it all? A scientist reflects on the gut-wrenching choices of juggling marriage, kids, and careers

Ultra-high sensitivity magnetic field and magnetization measurements with an atomic magnetometer

We describe an ultra-sensitive atomic magnetometer using optically-pumped potassium atoms operating in spin-exchange relaxation free (SERF) regime. We demonstrate magnetic field sensitivity of 160 aT/Hz$^{1/2}$ in a gradiometer arrangement with a measurement volume of 0.45 cm$^3$ and energy resolution per unit time of $44 \hbar$. As an example of a new application enabled by such a magnetometer we describe measurements of weak remnant rock magnetization as a function of temperature with a sensitivity on the order of 10$^{-10}$ emu/cm$^3$/Hz$^{1/2}$ and temperatures up to 420$^\circ$C

Foodborne Infections and the Global Food Supply: Improving Health at Home and Abroad

In recent years, fourteen percent of the U.S. food supply has been imported from other countries, including many fresh and perishable foods. Although most outbreaks of illness and individual cases are related to foods from the United States, large and unusual outbreaks have been traced to imported foods that were likely contaminated in the country of origin. Investigation of these outbreaks requires collaboration across several disciplines as well as across international borders. Successful investigation can not only control the original problem, but can also inform public authorities in both countries about the need for strategies to prevent similar outbreaks from happening in the future. Production of perishable foods in the developing world brings particular challenges because of the deficiencies in basic sanitation and hygiene and other elements of public health that Americans take for granted. The public health infrastructure in such countries is critical to identifying and controlling foodborne and waterborne challenges before they affect exported foods, and strengthening such infrastructure is an important part of general development efforts. Strategies to improve the health of the workers and rural populations in those countries and to increase the capacity of public health and food safety systems are likely to have long-term benefits to health in those countries, as well as preventing infections in the countries to which they export

The intensity of the time-averaged geomagnetic field: the last 5 Myr

The existing database for paleointensity estimates of the ancient geomagnetic field contains more than 1500 data points collected through decades of effort. Despite the huge amount of work put into obtaining these data, there remains a strong bias in the age and global distribution of the data toward very young results from a few locations. Also, few of the data meet strict criteria for reliability and most are of unknown quality. In order to improve the age and spatial distribution of the paleointensity database, we have carried out paleointensity experiments on submarine basaltic glasses from a number of DSDP sites. Of particular interest are the sites that provide paleointensity data spanning the time period 0.3-5 Ma, a time of relatively few high quality published data points. Our new data are concordant with contemporaneous data from the published literature that meet minimum acceptance criteria, and the combined data set yields an average dipole moment of 5.49 +/- 2.36*10^22 Am². This average value is comparable to the average paleofield for the period 5-160 Ma (4.2 +/- 2.3*10^22 Am²) [T. Juarez, L. Tauxe, J.S. Gee and T. Pick (1998) Nature 394, 878-881] and is substantially less than the value of approximately 8U1022 Am2 often quoted for the last 5 Myr (e.g. [McFadden and McElhinny (1982) J. Geomagn. Geoelectr. 34, 163-189; A.T. Goguitchaichvili, M. Preévot and P. Camps (1999) Earth Planet. Sci. Lett. 167, 15-34])

Proches aidants

Les proches aidants se retrouvent souvent à devoir assumer des tâches pour lesquelles ils n’ont pas été préparés et n’ont pas de formation adéquate. Face à la maladie de leur proche, ils peuvent parfois se sentir dépassé par la situation. Les besoins auxquels ils doivent répondre sont variés, et ils ne savent pas toujours où se renseigner. En collaboration avec deux psychologues, le projet consiste à mettre en place un site Internet avec un questionnaire, que le proche aidant peut remplir. En fonction de ses réponses, il reçoit un feed-back personnel sous forme de graphique, lui indiquant où il peut trouver de l’aide