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Stonehenge Experiment Needs Scaling Up



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Stonehenge Experiment Needs Scaling Up


Civil engineer Mark Whitby, who's been involved with other Stonehenge-construction experiments, thinks the ball method could work for smaller stones but isn't convinced it could shift a sarsen.

"The problem will be when the tip of the ball bears on the timber trough, it will bite" into the trough, possibly splitting the rail, said Whitby, who runs London-based +Whitby Structural Engineers. "When transporting lighter stones, this won't be a problem. But when they get to 30 and 40 tons, it will be."

Instead, Whitby prefers the sled theory - and even helped prove a sled could move a 40-ton replica sarsen for a 1997 BBC documentary.

Archaeologist David Batchelor, meanwhile, thinks the ball idea is plausible but isn't completely convinced.

The ball technique "seems to be a development of the sledge method," said Batchelor, of the government agency English Heritage. "But the added complexity needed to channel the track runners and then make the ball bearings all of one size seems to me a lot of work, which is probably unnecessary when animal-fat grease does the job."

Research leader Young counters that the sled system, even with its animal-fat lubrication, still results in a lot of friction. "Using wooden balls almost removes friction from the system and makes for a really efficient method of moving heavy weights around," he said.

Even so, Young realizes he needs to prove the new system can be scaled up to handle heavier loads. To that end, Young's team is seeking funding to repeat the experiment - this time with harder wood, stone balls, and oxen.

http://www.physorg.com/news/2010-12-big-gains-hospitalized-seniors.html

A few steps could lead to big gains for hospitalized seniors

"You'll be back on your feet in no time" is a phrase familiar to anyone who's ever had to spend time in a hospital. Now, a new study has shown that hospitalized elderly patients who literally "get back on their feet" by taking even short walks around a hospital unit tend to leave the hospital sooner than their more sedentary peers.

Conducted at the University of Texas Medical Branch at Galveston and described in a paper appearing in the current issue of Archives of Internal Medicine, the study draws on data collected from 162 hospitalized patients over age 65. Each patient was fitted with a pager-sized "step activity monitor" attached to his or her ankle - an electronic device capable of counting every step the patient took.

"Using these monitors, we were able to see a correlation between even relatively small amounts of increased mobility and shorter lengths of stay in the hospital," said Steve Fisher, a UTMB Health assistant professor and lead author on the paper. "We still found this effect after we used a statistical model to adjust for the differing severities of the patients' illnesses."

Clinicians have long recognized the importance of getting patients with orthopedic or neurologic conditions up and walking as soon as possible, but no such "standard of care" currently exists for older adults admitted for acute medical illnesses. According to the authors of the UTMB Health study, their work could serve as a first step toward that goal - and may also open the door to other improvements in hospital care for the elderly.

"Mobility is a key measure in older people's independence and quality of life generally, and this study suggests that's also true in the hospital setting," said Fisher. "When we hospitalize elderly people, we set up a paradoxical situation: you can have a positive outcome of the acute problem that brought them there, but still have negative consequences as a result of extended immobility."

Mobility in the hospital as measured by an activity monitor could potentially become a kind of vital sign for the elderly, Fisher said, as well as a tool that would help researchers find the minimal levels of activity necessary to protect elderly patients from long-term declines in function.

"This is very preliminary, but it's leading to a lot of questions right now that I think need to be answered," said UTMB Health professor Glenn Ostir, a co-author on the paper and director of research for the university's Acute Care for Elders unit. "We know from other research that mobility is linked to older people's quality of life, independence, maintenance of healthy muscle mass, all these things. And so we need to look at this and say what is the impact of mobility in the hospital on the overall health of the older person once they leave the hospital - do they rebound and do better, or do they wind up in a downward spiral that leads to increased re-hospitalization? The step monitors have given us the technology to potentially do this, and we're excited about the chance to answer these questions and make a positive difference in people's lives."

Provided by University of Texas Medical Branch at Galveston

http://www.physorg.com/news/2010-12-circulating-tumor-cells-recurrence-death.html

Circulating tumor cells predicted recurrence, death in patients with early-stage breast cancer

The presence of one to four circulating tumor cells (CTCs) in the blood of early-stage breast cancer patients almost doubled patient's risk of cancer relapse and death, and five or more CTCs increased recurrence by 400 percent and death by 300 percent, according to Phase III results of the SUCCESS trial.

These cells were found in patients after surgery but before chemotherapy treatment.

Results of this study were presented at the 33rd Annual CTRC-AACR San Antonio Breast Cancer Symposium, held Dec. 8-12, 2010, and demonstrate the value of CTCs in early breast cancer, independent of estrogen-receptor or HER2 status and before use of adjuvant therapy.

The benefit of using CTCs to predict risk for recurrence and death in metastatic breast cancer patients has been shown in a number of studies, and use of a CTC test in metastatic breast cancer has been approved by the Food and Drug Administration.

The CTCs found in this study are likely evidence that a tumor is shedding breast cancer cells, said lead researcher Brigitte Rack, M.D., head of the department of gynecological oncology at the Women's Hospital at the University of Munich, Germany. "The CTCs might have been released from the primary tumor before these patients underwent surgery, and the expression of stem cell markers on disseminated tumors cells has been shown by several groups."

Survival of these CTCs after chemotherapy further suggests they are cancer stem cells, Rack added.

Researchers with this study are testing the effectiveness of two different chemotherapy regimens and extended adjuvant bisphosphonate treatment in early breast cancer. SUCCESS' efficacy data are expected to be released next year.

Results of this study showed that 21.5 percent of patients had one or more CTC in their blood before the start of adjuvant treatment. These patients were more frequently node-positive, but no other linkage could be made with tumor size or grade or HER2 status.

Breast cancer recurred in 114 patients, and 66 patients died. Being CTC-positive was a significant independent predictor for both disease-free and overall survival. Patients with one to four CTCs had an 88 percent increased risk of early breast cancer recurrence and a 91 percent increased risk of death from breast cancer, according to Rack.

Prognosis was worse in patients with five or more CTCs; these patients had a fourfold risk of cancer recurrence and a threefold risk for death from the disease.

"Our study suggests testing CTCs may prove to be important to help individualize therapy for early-stage breast cancer where no measurable tumor is present," she said. "Patients who seem to be at high risk due to CTC may benefit from additional treatment options, and those that don't have CTCs may be spared side effects of some treatments."

She added, however, that prospectively randomized trials are necessary to show an improvement of survival based on CTC diagnostics. Trials testing this notion are either ongoing or about to start in Europe and the United States, according to Rack. Provided by American Association for Cancer Research



http://www.scientificamerican.com/podcast/episode.cfm?id=what-makes-an-honest-smile-honest-10-12-11


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