Precision atomic spectroscopy for improved limits on variation of the fine structure constant and local position invariance

We report tests of local position invariance and the variation of fundamental constants from measurements of the frequency ratio of the 282-nm 199Hg+ optical clock transition to the ground state hyperfine splitting in 133Cs. Analysis of the frequency ratio of the two clocks, extending over 6 yr at NIST, is used to place a limit on its fractional variation of <5.8x10(-6) per change in normalized solar gravitational potential. The same frequency ratio is also used to obtain 20-fold improvement over previous limits on the fractional variation of the fine structure constant of |alpha/alpha|<1.3x10(-16) yr-1, assuming invariance of other fundamental constants. Comparisons of our results with those previously reported for the absolute optical frequency measurements in H and 171Yb+ vs other 133Cs standards yield a coupled constraint of -1.5x10(-15)<alpha/alpha<0.4x10(-15) yr-1 and -2.7x10(-15)<d/dtlnmicroCs/microB<8.6x10(-15) yr-1.

Single-atom optical clock with high accuracy

For the past 50 years, atomic standards based on the frequency of the cesium ground-state hyperfine transition have been the most accurate time pieces in the world. We now report a comparison between the cesium fountain standard NIST-F1, which has been evaluated with an inaccuracy of about 4 x 10(-16), and an optical frequency standard based on an ultraviolet transition in a single, laser-cooled mercury ion for which the fractional systematic frequency uncertainty was below 7.2 x 10(-17). The absolute frequency of the transition was measured versus cesium to be 1,064,721,609,899,144.94 (97) Hz, with a statistically limited total fractional uncertainty of 9.1 x 10(-16) the most accurate absolute measurement of an optical frequency to date.

Teaching preventive cardiology: the consultation clinic

Atherosclerotic heart disease is the principal cause of death in the United States and other industrial societies. Three major risk factors for developing coronary artery disease (hypertension, hypercholesterolemia, and smoking) are frequently seen in family practice patients. It is therefore important for family physicians to be able to assess an individual patient's overall heart disease risk and provide advice and counseling to reduce that risk. This article describes a teaching-consultation clinic in which family practice residents learn to assess cardiac risk in patients and develop counseling skills to manage that risk. The role of the family physician in relation to the cardiologist is also discussed. Medical Subject Headings (MeSH): preventive medicine, cardiology, residency.

Preventive medicine matrix as a residency curriculum development tool

Preventive medicine has become a central issue in health care reform, but how best to teach and implement health promotion/disease prevention (HP/DP) in clinical practice is still undefined. This article describes the Preventive Medicine Matrix as a tool to help organize the complex and broad area of prevention into a workable curriculum for residency programs. The matrix is divided into life-cycle periods and HP/DP curricular topics. Using the matrix, a program can assess the areas it is addressing well and those that require emphasis. A major strength of the matrix is its flexibility, which allows modifications for the different needs of individual programs.

Accuracy of patient recall and chart documentation of falls

BACKGROUND

This 1-year prospective study examined the accuracy of patient recall of falls and fall injuries and completeness of chart documentation of these events.

METHODS

One hundred ambulatory geriatric family practice patients reported falls weekly by postcard with telephone call follow-up. On a final postcard they reported their recall of falls and fall injuries in the preceding 3-, 6-, and 12-month periods. Patient charts were reviewed for fall documentation.

RESULTS

For the 3-, 6-, and 12-month periods, respectively, 31 percent, 44 percent, and 89 percent of participants who had reported a fall recalled at least one fall. Sixty-eight percent of participants who had reported an injury recalled one at the year's end. The positive predictive value of recalling a fall was 92 percent and of recalling a fall injury was 72 percent for the 1-year period. Only 10 of 56 (18 percent) reported falls were documented in the patient's chart.

CONCLUSIONS

Patients recalled falls and injuries in the previous 12 months well, but they were less accurate for recall periods of 3 and 6 months. Few reported falls were documented by the patient's physician. Awareness of falls can be increased by asking the patient about falls during the previous year and by documenting all reported and recalled falls.

Leiomyosarcoma of the femoral vein in a marathon runner

Leiomyosarcoma of the femoral vein is a rare tumor. Physicians involved in the care of athletic patients must not be cavalier in evaluating overuse injuries and should endeavor to make a specific diagnosis. If atypical findings, such as generalized extremity swelling, are present, the physician must consider systemic illness including malignancy in apparently healthy, physically active individuals.

Physician estimates as predictors of elderly patients' mobility scores

In a previous study, residency physicians' estimates of patients' mobility scores were strongly associated with the patients' actual scores. The present study tested the hypothesis that community physicians would similarly be able to predict patients' mobility scores. Dysmobility risk-factor questionnaires were given during routine office visits to 120 ambulatory and mentally competent patients older than age 65. After the visit, the attending physician estimated the patient's mobility score (PEMS), and the patient independently underwent mobility testing. The PEMS was 71% sensitive and 80% specific in selecting those patients who had a mobility score of less than 30. Choosing patients with low PEMS or high age (75+) increased sensitivity (96%) while decreasing specificity (53%). Alternatively, selecting only patients over age 75 with low PEMS or problems walking had a sensitivity of 78% and specificity of 86%. This study suggests that by using pretests, the physician can exclude many elderly patients from mobility testing while detecting most of those who are dysmobile.

Predicting elderly patients' mobility using fall history and physician assessment

This study tested whether a patient's history of falls or an office clinician's general assessment can predict which ambulatory elderly patients will do poorly on mobility testing. Ambulatory patients making routine visits who were age 65 or older, mentally competent, and not acutely ill were eligible. Fifty-two (91%) of these patients participated by completing a fall history questionnaire and undergoing mobility testing. After the visit, the attending physician estimated how the patient would score on the mobility test. Twelve (23%) of the patients reported falls and seven (13.5%) reported fall injuries in the preceding year. Both fall history and physician estimate of mobility score significantly correlated with the measured mobility score. Only the physician estimate of mobility score, however, had adequate sensitivity (94.4%) and specificity (82.4%) to be clinically useful. This estimate will allow the clinician to selectively apply mobility testing to those patients likely to score poorly.

The interaction between a series of acid azo dyestuffs and nonionic surfactants in aqueous solution

The diffusion of a series of seven acid dyes in aqueous solutions in the absence and presence of nonionic surfactants has been investigated. Some indications have been obtained regarding the mechanism of interaction between the two species in solution.

A large deletion of the long arm of chromosome No. 4 in a child with limb abnormalities

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