sealPurdue Science and Health Briefs

December 1997

Holidays need not be torture for those watching their weight

WEST LAFAYETTE, Ind. -- Holidays can be a torturous time for those trying to maintain a healthy weight. Pumpkin pie, peanut brittle and Grandma's famous fudge are tempting delights. However, the next few weeks do not have to be torture, if you plan ahead, says a Purdue University nutrition expert.

Olivia Bennett Wood, associate professor of foods and nutrition, offers two options that can fit into any lifestyle. "You can plan to not gain weight by exercising, eating small portions and eating before going to holiday parties, or you can plan to indulge yourself to a limited extent during the holidays but lose the weight in January," she says.

If you plan to allow yourself to gain several pounds during the holidays, gain only the amount you know you can lose. Wood suggests keeping the indulgence in check so the amount gained can be shed within one month. She advises that you plan the ways you will lose the extra pounds, then set goals for weight loss each week and stick to them.

Avoiding weight gain can be as easy as adding 10 minutes to your regular exercise routine or taking the stairs instead of the elevator.

The abundance of food at many holiday parties can lead to over-indulgence. Here are some sensible eating tips from Wood:

CONTACT: Wood, (765) 494-8238; e-mail,

This 'doctor' makes house calls

NOTE TO JOURNALISTS: A color photograph of Dennis Minchella tutoring students in a Purdue residence hall is available. Ask for the photo called Minchella/Housecalls

WEST LAFAYETTE, Ind. -- A freshman biology course at Purdue University brings 700 students to Dennis Minchella's lectures twice each week. But for the past three years, he also has been bringing the course to his students.

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The associate professor of biology holds study sessions in residence hall lounges and student union dining rooms to answer questions and offer explanations of material being covered in his large lecture sessions, which are by necessity far less personal that he would wish.

Minchella calls it Mobile Operation in Biological Science, but his students like to refer to it as "Mo' BS."

"There are lots of advantages to going to the students rather than making them come to me," Minchella explains. "They are much more comfortable in their own environment. It also forces them to get a group of friends together, which I encourage anyway for a study group."

Minchella's course is required for all biology majors at Purdue, but it also is taken by students in pre-veterinary science, health science and liberal arts.

The Mobile Operation in Biological Science sessions are held for two to three weeks during the most difficult part of the semester whenever at least eight students sign up to attend. Minchella frequently visits three different residence halls in a single evening of tutoring.

"We talk primarily about the material they need to know for class, but we talk about a lot of other things, too," he says. "They ask about the kinds of careers available in biology, or what medical school is like. They're also curious about what kind of research I do and often ask me to suggest courses for them to take next semester. I couldn't get that kind of interaction anywhere else."

In addition to seeing that students do well in his class, Minchella also tries to help them establish good study habits early in their college careers.

"For students who are planning to be biology majors, it's critical that they get off on the right foot," Minchella says. "Otherwise they're going to drop the class, and possibly leave science. Because there's no way to tell which one is going to be the next great scientist, I want to help them all. Not just the superstars, but especially the ones who are close to not making the cut."

He's speaking from experience. Minchella admits to struggling academically during his first semester of undergraduate work, and he shares that with his students.

"I think there is a large fraction of students who aren't especially well-prepared coming in, but they have the capabilities," Minchella explains. "They can do it if they believe in themselves, so if you help them a bit at the beginning with things like self-confidence and perseverance, that gets a large number of the at-risk students over the top."

CONTACT: Minchella, (765) 494-8188; e-mail,

Grassy lots reap 'green' for developers, environment

NOTE TO JOURNALISTS: Color photos of a seeded and an unseeded lot are available. Ask for the photos called Harbor/Lots.

WEST LAFAYETTE, Ind. -- An undeveloped residential lot that's covered with grass is likely to bring a bigger profit to the developer than a more typical bare-soil lot, according to a Purdue University study. The grass-covered lot also will profit the environment.

Purdue researchers and their collaborators from two Soil and Water Conservation Districts in Ohio and Indiana released details of the study Oct. 15 during on-site demonstrations in northeast Ohio.

Using a consumer survey approach, the researchers tested whether grass-covered lots are valued more highly by developers, real estate agents and home buyers than bare lots. Although developers placed little value on differences in appearance, real estate agents and home buyers placed a much higher value on grass-covered lots. In the study, home buyers perceived grassed lots to be worth $750 more than comparable bare lots.

"This increase in value is more than double the cost of seeding a residential lot, giving a 150 percent return on investment" says Martha Herzog, a Purdue graduate student in the Department of Earth and Atmospheric Science who was the lead researcher on the project. "For a 100-lot site, seeding can increase the profit on the development by $45,000."

Herzog coupled her findings with a 2-year-old environmental study completed by Jon Harbor, Purdue associate professor of earth and atmospheric science, that showed widespread seeding and mulching on a residential construction site reduced soil erosion by up to 86 percent and significantly reduced the levels of phosphorus washed into to nearby rivers. The study was published in the journal Physical Geography.

"Soil erosion from construction sites is a significant cause of surface water quality degradation in the United States, particularly in developing areas," Harbor says. "Construction sites are a major source of pollution because as land is exposed and disturbed, soil erosion rates are dramatically increased. Much of the displaced sediment eventually reaches waterways where sedimentation can alter the physical and biological characteristics of streams, rivers, lakes and reservoirs."

Though most construction sites are required by state or local regulations to take measures to control erosion, the regulations don't apply to residential lots of less than five acres that are not part of a larger development, Harbor says.

The research group now is tracking the sale of seeded and unseeded lots in the same areas to determine the actual differences in the selling prices and in how quickly the lots sell.

"What we're trying to do with this study is show that taking measures to control erosion also makes good business sense," Harbor says.

The participating Soil and Water Conservation Districts are in Geauga County, Ohio, and St. Joseph County in northern Indiana.

Herzog's project was supported by a grant from the Great Lakes Commission.

CONTACTS: Herzog, (765) 494-0258; Harbor, (765)494-9610; e-mail,

Compiled by Amanda Siegfried, (765) 494-4709; e-mail,
Purdue News Service: (765) 494-2096; e-mail,


Associate Professor Dennis Minchella tutors students at Purdue's Shealy Residence Hall. Pictured clockwise from Minchella are freshman Jackie Webster, a pre-veterinary science major from Crown Point, Ind., and freshman Lisa Graves, a neurobiology major from Southport, Ind. (Purdue News Service Photo by David Umberger)
Color photo, electronic transmission, and Web and ftp download available. Photo ID: Minchella.housecalls
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