Zeeman-tuned rotational level-crossing spectroscopy in a diatomic free radical.

Rotational levels of molecular free radicals can be tuned to degeneracy by using laboratory-scale magnetic fields. Because of their intrinsically narrow width, these level crossings of opposite-parity states have been proposed for use in the study of parity-violating interactions and other applications. We experimentally study a typical manifestation of this system using BaF138. Using a Stark-mixing method for detection, we demonstrate level-crossing signals with spectral width as small as 6 kHz. We use our data to verify the predicted line shapes, transition dipole moments, and Stark shifts and to precisely determine molecular magnetic g factors. Our results constitute an initial proof of concept for use of this system to study nuclear spin-dependent parity-violating effects.

Using molecules to measure nuclear spin-dependent parity violation.

Nuclear spin-dependent parity violation arises from weak interactions between electrons and nucleons and from nuclear anapole moments. We outline a method to measure such effects, using a Stark-interference technique to determine the mixing between opposite-parity rotational/hyperfine levels of ground-state molecules. The technique is applicable to nuclei over a wide range of atomic number, in diatomic species that are theoretically tractable for interpretation. This should provide data on anapole moments of many nuclei and on previously unmeasured neutral weak couplings.

An easily constructed, tuning free, ultra-broadband probe for NMR.

We have developed an easy to construct, non-resonant wideband NMR probe. The probe is of the saddle coil geometry and is designed such that the coil itself forms a transmission line. The probe thus requires no tuning or matching elements. We use the probe with a spectrometer whose duplexer circuitry employs a simple RF switch instead of the more common lambda/4 lines, so the entire probe and spectrometer perform in an essentially frequency-independent manner. Despite being designed with electro- and magnetostatic formulas, the probe performs well at frequencies up to 150 MHz and beyond. We expect that with additional design effort, the probe could be modified for use at significantly higher frequencies. Because our construction method relies on commercial circuit fabrication techniques, identical probes can be easily and accurately produced.

Transcriptional control of genes encoding CS1 pili: negative regulation by a silencer and positive regulation by Rns.

The adherence of enterotoxigenic Escherichia coli (ETEC) to the human small intestine is an important early event in infection. Attachment is thought to be mediated by proteinaceous structures called pili. We have investigated the regulation of expression of the genes encoding CS1 pili found on human ETEC strains and find that there are at least three promoters, P1 and P2, upstream of the coo genes, and P3, downstream of the start of cooB translation. We identified a silencer of transcription which extends over several hundred bases overlapping the cooB open reading frame. This silencer is dependent on the promoter and/or upstream region for its negative effect. The DNA binding protein H-NS is a repressor of coo transcription that acts in the same region as the silencer, so it is possible that H-NS is involved in this silencing. Rns, a member of the AraC family, positively regulates transcription of the coo operon and relieves the silencing of CS1 expression.

Family practice residency program directors' views on research.

BACKGROUND AND OBJECTIVES: The culture of family practice training programs does little to convince residents that research is a worthwhile and important activity. The traditional dichotomy between research and clinical medicine persists today, despite an identified clinical mission for research. METHODS: As part of an effort to build the research capacity of family practice training programs, a telephone survey was administered in August 1995 to the program directors of all residency programs listed in the American Academy of Family Physicians 1995 Directory of Family Practice Residency Programs. The directors were asked about their program's research environment, features designed to promote research activity, and the level of resident research productivity. RESULTS: More than half (53.6%) of the program directors felt that their training program actively promotes research. Three out of four indicated that involving residents in research is a goal of their program. However, only four of 10 (40.8%) programs provide specific time for research, and family practice residents appear to be relatively inactive by conventional measures of research productivity. CONCLUSIONS: Research appears to be developing a limited role in family practice training programs. Resident research productivity remains relatively low and may be a result of residency programs not providing specific time for participating in research. However, the program directors' supportive attitudes may contribute to research and scholarly activity becoming an integral part of a family physician's training.

Right mandible swelling of unknown origin.

Infantile cortical hyperostosis (ICH), or Caffey's disease, has a low prevalence, is not easily recognized clinically, and is seldom reported in the primary care literature. A case of infantile cortical hyperostosis of the right mandible of a newborn is reported. Multiple radiographic tests, as well as bone biopsy, were necessary to establish a definitive diagnosis. The most striking features of this disease are presented, including the clinical and physical presentation, radiographic characteristics, and pathology.

Does grandma need condoms? Condom use among women in a family practice setting.

OBJECTIVE: To examine the relationship between age and condom use among women who are typically seen in the primary care setting. DESIGN: Survey of a population using a self-administered questionnaire. SETTING: Four community-based family practice clinics located in a low-income, racially mixed geographical area. PATIENTS: All consenting patients (N = 995) during their visits for routine Papanicolaou tests. The mean age of patients was 35 years, with a range of 75 years (12 to 87 years). Respondents were predominantly black (63.2%), 39.2% were single, and over 65% had incomes no greater than $15,000/y. MAIN OUTCOME MEASURE: The outcome measure of condom use is reported. Data analysis of patients' sexual behavior revealed that older women might be at risk for sexually transmitted diseases (STDs). The hypothesis that condom use is related to age emerged during data collection. RESULTS: Condom use is related to being younger (< 31 years), having had an STD, having a sexual partner in whom an STD was diagnosed, having a lower income, or being single or black. In multivariate models, marital status (single), age (< 31 years), and having a partner with an STD remain significant. Among unmarried women, the effects of age, race, and a partner with STD remain, and being a nonsmoker is also significant. In the multivariate analysis for unmarried women, only age (< 31 years) is significantly related to condom use. An independent random sample of charts revealed that almost 45% of the patients aged 45 years or younger received condom counseling, whereas condoms were discussed with none of those older than 45 years. CONCLUSIONS: Because older patients (those beyond child-bearing years) are less likely to use condoms and evidently receive little education about condom use, older patients must be educated about the need for condoms.

Developing a research program in a community-based department of family medicine: one department's experience.

BACKGROUND: There is a growing consensus that an improved research environment is needed for family medicine to continue to evolve. At the same time, there is relatively little discussion about practical ways to implement such an environment. Many believe that our efforts in this area lag far behind our accomplishments in education, training, and the practice of family medicine. PROGRAM DESCRIPTION: This manuscript discusses one community-based academic department's experience in formulating and implementing a research program. By slowly involving faculty in research and by instructing and encouraging residents, a research environment can be incorporated into a residency program's routine. The approach described in this manuscript is evolutionary and relies on committing resources to research while slowly involving faculty and residents in the process. PROGRAM EVALUATION: Measures of research output (funding, publishing in refereed journals, and presenting at professional conferences) suggest that the program has achieved some momentum in the area of research. Although relatively modest by the standards of some university-based programs, the program's achievements demonstrate that a community-based, university-affiliated program can initiate a viable research effort. CONCLUSIONS: Our experience has taught us that implementing a research program is a relatively lengthy process comprised of multiple components. First, individual projects typically consist of a process of funding, presenting, and publishing. Sharing research results with colleagues locally and at professional meetings is an especially important socialization component of research and scholarship. Second, it is important to use refereed and nonrefereed journals as outlets for scholarship, since the process of writing is itself important, especially for family physicians who lack formal research training. Finally, funding proposals and publications almost always require revision and resubmission, a process which contributes to creating and further refining the skills needed by successful researchers.

Patient attitudes toward physician treatment of obesity.

BACKGROUND: Family physicians are frequently faced with the problem of caring for overweight patients since 30% to 40% of American adults are overweight and 10% are obese. The traditional approach of physicians treating obese patients, which includes diet instruction, dietitian referral, and supportive therapy, has demonstrated little success. METHODS: A focus group of obese patients was formed to discuss weight-loss therapy from a patient viewpoint. Three sessions were completed, one each for patients' feelings and life experiences, exercise, and eating habits. The traditional medical approach to weight-loss therapy was discussed. RESULTS: All participants reported having failed physicians' attempts to aid them in weight loss. Similarly, all related negative life experiences, job discrimination, and derogatory remarks that they attributed to their weight. Participants were not supportive of physicians' traditional approach to aiding patients with weight loss. CONCLUSIONS: The results suggest that the traditional approach to treating patients' excessive weight is not helpful from the patient viewpoint. Study participants were more supportive of a group approach to the treatment of obesity that would include group exercise and modification of currently used foods rather than new low-calorie recipes. The issues of transportation and child care must be addressed by weight-loss programs.

Predicting atypical Pap smear progression: a case-control study.

OBJECTIVE: This case-control study proposed to define risk factors for progression of cervical disease beyond an atypical level, and to explore the possibility of a clinical tool that would aid the clinician in deciding on the need for colposcopy. METHODS: Twenty-three hundred (2,300) abnormal Papanicolaou smears were reviewed to identify documented cases of class II Papanicolaou smears that had progressed. Controls were randomly chosen for each case from the remaining pool of available class II Papanicolaou smears that did not progress. Data analyses were conducted to determine the predictive value of information that would be in a patient's chart with respect to progression from class II Papanicolaou smear to a higher level of disease. RESULTS: A univariate analysis revealed several significant variables, including age, education, attendance at a public clinic, marital status, notification of Papanicolaou results, and a history of sexually transmitted disease. Next, a multivariate analysis demonstrated that a group of significant variables could not be defined, and only notification of an atypical Papanicolaou smear was significant. CONCLUSIONS: The study's findings suggest that the data available in a patient's medical record are not sufficient to develop a risk assessment scale and provide evidence of the need for continued study in this area.

Oxygen uptake as a determinant of gastric blood flow autoregulation.

Autoregulation of blood flow in the denervated, autoperfused dog stomach was studied before and during local intraarterial infusion of histamine. Histamine caused an increase in gastric blood flow and oxygen uptake. The increased oxygen uptake was due entirely to an increased blood flow, ie, oxygen extraction was not altered by histamine infusion. When oxygen uptake by the stomach was less than 2.0 ml/min/100 g, there was no evidence of blood flow autoregulation, while an oxygen uptake greater than 4.0 ml/min/100 g was consistently associated with blood flow autoregulation. The data indicate that histamine enhances the ability of the stomach to autoregulate its blood flow. This effect appears to be due to histamine's influence on gastric oxygen uptake.