Observations of the Interaction and Transport of Fine Mode Aerosols with Cloud and/or Fog in Northeast Asia from Aerosol Robotic Network (AERONET) and Satellite Remote Sensing.

Analysis of sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in mid-visible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological co-variation with atmospheric stability and convergence. The new development of Aerosol Robotic network (AERONET) Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the Spectral Deconvolution Algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter-summer period, comparisons of AERONET L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.

Explaining the sawtooth: latitudinal periodicity in a circadian gene correlates with shifts in generation number.

Many temperate insects take advantage of longer growing seasons at lower latitudes by increasing their generation number or voltinism. In some insects, development time abruptly decreases when additional generations are fit into the season. Consequently, latitudinal 'sawtooth' clines associated with shifts in voltinism are seen for phenotypes correlated with development time, like body size. However, latitudinal variation in voltinism has not been linked to genetic variation at specific loci. Here, we show a pattern in allele frequency among voltinism ecotypes of the European corn borer moth (Ostrinia nubilalis) that is reminiscent of a sawtooth cline. We characterized 145 autosomal and sex-linked SNPs and found that period, a circadian gene that is genetically linked to a major QTL determining variation in post-diapause development time, shows cyclical variation between voltinism ecotypes. Allele frequencies at an unlinked circadian clock gene cryptochrome1 were correlated with period. These results suggest that selection on development time to 'fit' complete life cycles into a latitudinally varying growing season produces oscillations in alleles associated with voltinism, primarily through changes at loci underlying the duration of transitions between diapause and other life history phases. Correlations among clock loci suggest possible coupling between the circadian clock and the circannual rhythms for synchronizing seasonal life history. We anticipate that latitudinal oscillations in allele frequency will represent signatures of adaptation to seasonal environments in other insects and may be critical to understanding the ecological and evolutionary consequences of variable environments, including response to global climate change.

A rapid diagnostic and treatment center for patients with chest pain in the emergency department.

STUDY OBJECTIVE: To evaluate a comprehensive diagnostic 9-hour evaluation (Heart ER Program) for patients with possible acute ischemic coronary syndromes. DESIGN: Retrospective review of consecutive patients. SETTING: Urban tertiary care emergency department. PARTICIPANTS: A total of 1,010 patients with symptoms suggestive of acute ischemic coronary syndrome was enrolled in the Heart ER Program over the first 32 months of operation. Patients with history of coronary artery disease, hemodynamic instability, acute ST-segment elevation or depression of more than 1 mm, or a clinical syndrome consistent with unstable angina were directly admitted to the hospital. INTERVENTION: Patients underwent serial testing for creatine kinase (CK-MB) on presentation to the Heart ER and 3, 6, and 9 hours later with continuous 12-lead ECGs/serial ST-segment trend monitoring for 9 hours. Two-dimensional echocardiography and graded exercise testing were performed in the ED after the 9-hour evaluation period. RESULTS: Of 1,010 patients, 829 (82.1%) were released home from the ED; 153 (15.1%) required admission for further cardiac evaluation. Fifty-two of 153 (33.9%) admitted patients were found to have a cardiac cause for their symptoms; 43 had acute ischemic coronary syndromes (12, acute myocardial infarction; 31, angina or unstable angina). CONCLUSION: The Heart ER program provides an effective method for evaluating low- to moderate-risk patients with possible acute ischemic coronary syndrome in the ED setting.

Role of emergency medicine residency programs in determining emergency medicine career choice among medical students.

STUDY OBJECTIVE: To characterize the role of emergency medicine residency programs in determining emergency medicine career choice among medical students. DESIGN: Observational, cross-sectional, descriptive study. Information on student career choice was obtained through a targeted query of the National Resident Matching Program data base, simultaneously stratified by specialty and school, and adjusted for class size. PARTICIPANTS: All accredited emergency medicine residency programs and four-year allopathic medical schools. RESULTS: Fifty-two schools (42%) had a closely affiliated emergency medicine residency program, ie, one based primarily at the institution's main teaching hospital(s). This configuration was associated with a 70% increase in the median proportion of students choosing emergency medicine as a career when compared to the 73 schools with no closely affiliated emergency medicine residency (5.1% vs 3.0%, P < .0001). When institutions were stratified by overall commitment to emergency medicine, the median proportion of students choosing emergency medicine as a career was 2.9% for institutions with a minimal commitment to emergency medicine (neither an academic department of emergency medicine nor a closely affiliated emergency medicine residency), 4.1% for institutions with a moderate commitment to emergency medicine (either a department of emergency medicine or an emergency medicine residency, but not both), and 5.7% for institutions with a substantial commitment to emergency medicine (a department of emergency medicine and an emergency medicine residency) (P < .0001). When institutional commitment to emergency medicine was examined in a simple multivariate model, only the presence of an emergency medicine residency was associated independently with student career choice (P < .001). CONCLUSION: An emergency medicine residency program that is closely affiliated with a medical school is strongly and independently associated with a quantitatively and statistically significant increase in the proportion of students from that school who choose a career in emergency medicine. These data support the proposition that, if emergency medicine is to meet national manpower shortage needs by attracting students to the specialty, it must establish residency programs within the primary teaching hospital(s) of medical schools. Such a configuration does not currently exist in the majority of schools.

Emergency-department diagnosis of acute myocardial infarction and ischemia: a cost analysis of two diagnostic protocols.

OBJECTIVE: To assess the potential cost savings of the emergency-department (ED) diagnosis of acute myocardial infarction (AMI) and other myocardial ischemia using a nine- hour ED evaluation protocol. METHODS: This one-year study of chest-pain evaluation unit (CPEU) patient charges was undertaken at two midwestern urban university hospital EDs. Included in the study were 447 patients presenting to the EDs with chest pain consistent with myocardial ischemia, nondiagnostic electrocardiograms (ECGs), and stable vital signs. Following initial ED evaluation, CPEU patients underwent nine hours of continuous ECG ST-segment monitoring with serum CK-MB levels determined at zero, three, six, and nine hours. Nonrandomized concurrent chest pain patients with routine ED evaluation and hospital admission without CPEU workup served as controls. At Center 1, patients with negative CPEU evaluations underwent immediate echocardiography (echo) and graded exercise testing (GXT) followed by ED release (CPEU;REL). At Center 2, CPEU patients were released from the ED for outpatient stress thallium testing (CPEU;REL). At Center 2, CPEU patients with positive workups as indicated by elevated CK-MB levels, ischemia by ST-segment monitoring, or positive echo/GXT/ stress thallium testing were admitted to the hospital for further testing. Control patients were admitted directly to the hospital to evaluate for AMI. Hospital charges for CPEU and control groups were compared. RESULTS: (Total charges in dollars, mean +/- SD, student's t-test): [table: see text] CONCLUSION: At both centers, hospital charges related to the acute evaluation of chest pain were significantly lower with this ED diagnostic protocol for AMI and myocardial ischemia.

Current status of academic emergency medicine within academic medicine in the United States.

OBJECTIVE: To characterize the status of emergency medicine within U.S. academic medical centers. METHODS: All accredited emergency medicine residency programs and all four-year allopathic medical schools in the United States were identified. Institutions were defined as academic medical centers based upon NIH research grant funding. These institutions were ranked using five measures of academic stature: a survey of medical school deans, a survey of internal medicine residency directors, level of research funding, characteristics of the student body, and an unweighted composite variable reflecting overall academic stature. The relationship between institutional academic stature and an empiric scale of institutional affiliation with emergency medicine was assessed. RESULTS: Sixty-two institutions were designated academic medical centers. These medical schools captured 90% of all NIH grant monies awarded in fiscal year 1990. Twenty-six of 87 emergency medicine residency programs (30%) were closely affiliated with one of these medical schools. Within academic medical centers, the presence of a residency or an academic department of emergency medicine was inversely associated with the medical school deans' ranking (p < 0.005), research rank (p < 0.001), and composite academic rank (p < 0.001). CONCLUSION: The majority of emergency medicine residency programs (70%) are not closely affiliated with institutions receiving the bulk (90%) of NIH resources for research. Within the institutions receiving the majority of NIH funding, there is a quantitatively and statistically significant inverse association of institutional emergency medicine affiliation and institutional academic rank.

Factors associated with career longevity in residency-trained emergency physicians.

STUDY OBJECTIVE: To test the hypothesis that residency-trained emergency physicians who left the practice of emergency medicine do not differ significantly from those who continue to practice. DESIGN: A retrospective cohort study using a mailed questionnaire. TYPE OF PARTICIPANTS: Eight hundred fifty-eight emergency medicine residency graduates from 1978 through 1982. METHODS: A mailed questionnaire was used to obtain data from the study population. Individuals who did not respond to the first mailing were sent a second survey six weeks later. A sample of 10% of nonrespondents was contacted by telephone and compared with respondents on five variables. Respondents were divided into physicians who continued to practice emergency medicine and those who had elected to leave the specialty. The variables used to compare the two groups included personal and professional demographics, career satisfaction, and satisfaction with training. chi 2, Fisher's exact t-test, and logistic regression were used to analyze the data with an a priori level of significance set at .05. MEASUREMENTS AND MAIN RESULTS: There were 539 complete responses for a response rate of 62.8%. No statistical differences between responders and nonresponders were identified. The ten-year survival rate of respondents was 84.9%. Those who left emergency medicine were less likely to be board certified in emergency medicine (P less than .001), were more likely to be board certified in another field (P = .001), were less likely to work with residents during their emergency medicine practice (P = .009), and were more likely to report an annual gross income of less than $100,000 per year (P less than .001). Emergency physicians who have left the field were less likely to report being satisfied or very satisfied with their initial choice of emergency medicine as a specialty (P = .001). There was no difference in satisfaction with the quality of emergency medicine residency training (P = .183). CONCLUSION: Career longevity of residency-trained emergency physicians has been greater than early predictions. Interactions with residents, higher income, satisfaction with training decision, and board certification in emergency medicine are variables associated with a higher retention rate.

Descriptive analysis of residency-trained emergency medicine physicians.

The purpose of this study was to analyze the demographics, practice characteristics, and job satisfaction of physicians who completed emergency medicine residencies. A questionnaire was mailed to 858 physicians who graduated from residencies between 1978 and 1982. A 62.8% response rate (n = 539) was achieved. The majority of respondents were satisfied or very satisfied with their choice of a career in emergency medicine and with the quality of their residency training. Over 22% of respondents cited lack of preparation to perform administrative tasks as a significant weakness of their residency training. The results of survey indicate that emergency medicine physicians are engaged primarily in clinical practice, but that administrative duties increase rapidly in the years following residency graduation. Emergency medicine physicians are still highly concentrated in states in which emergency medicine residencies are located. The percentage of graduates choosing academic careers is smaller than reported in studies of earlier graduates.

Single-dose ceftriaxone treatment of urinary tract infections.

Single-dose antibiotic therapy for urinary tract infections in which no underlying structural or neurologic lesions are present holds the promise of greater patient compliance and convenience. We present the results of a study comparing a single intramuscular dose of a long-acting, third-generation cephalosporin, ceftriaxone, with a standard, five-day regimen of trimethoprim-sulfamethoxazole (TMS). Fifty-two patients were entered into the study. After randomization, 26 were assigned to the TMS group and 26 were assigned to the ceftriaxone group. Of the patients who completed the study, 13 of the TMS group had positive cultures at the time of initial presentation, and 20 of the ceftriaxone group had positive cultures. There was no statistical difference between the groups in symptoms of dysuria, hematuria, frequency, flank pain, and nocturia (alpha = .05). The physical parameters of age, blood pressure, pulse, and temperature were similar in the two groups (alpha = .05), as were the types of infecting organisms (alpha = .05). When comparing the two regimens, the ceftriaxone group cure rate (18 of 20, 90%) was not found to be significantly different from that of the TMS-treated control group (13 of 13) (alpha = .05).

Treatment of cutaneous abscess: a double-blind clinical study.

Controversy exists about the value of antibiotic therapy following incision and drainage of cutaneous abscess. We undertook a randomized double-blind study to clarify the controversy. Adult patients with cutaneous abscesses who received outpatient surgical therapy were entered into the study. Following incision and drainage, patients received cephradine or placebo for seven days using a randomized code in a double-blind fashion. At the end of seven days, patients were reevaluated. Twenty-seven patients were treated with cephradine, and 23 with placebo. Ninety-six percent of the patients in each group were improved clinically after seven days. We conclude that cephradine did not alter the outcome of cutaneous abscesses at one week after incision and drainage. The implications are twofold: patients are not exposed to the potential side effects and allergic reactions of antibiotics, and the cost of health care can be reduced by not prescribing antibiotics in these patients.

Bilateral pneumothorax in an intravenous drug abuser.

Pneumothorax is a condition commonly encountered by emergency physicians. Bilateral pneumothorax is a rare occurrence. We present a case of self-induced bilateral pneumothorax in an intravenous drug abuser. Causes of bilateral pneumothorax are reviewed.

Emergency phenytoin loading by constant intravenous infusion.

We evaluated the efficacy of constant intravenous (IV) phenytoin infusion. Thirty-eight patients were evaluated prospectively for complications of continuous-infusion phenytoin loading. A total dose of 18 mg/kg was administered as a solution of 500 mg phenytoin in 50 mL normal saline using a constant infusion pump. The initial delivery rate was 40 mg/min. Cardiac rhythm was monitored by telemetry, and rhythm strips and vital signs were obtained every 15 minutes during infusion. Therapeutic phenytoin blood levels (greater than 10 micrograms/mL) were achieved in 37 patients (97%). Infusion was discontinued in one patient because of IV site irritation shortly after initiation of the infusion. Phenytoin levels in the toxic range were seen immediately postinfusion in 22 patients and in the four-hour postinfusion samples of 16 patients. Thirteen of 18 levels drawn 12 to 24 hours after infusion were therapeutic. Phenytoin levels greater than 20 micrograms/mL were tolerated without significant change in rhythm, QRS interval, or QT interval. A small statistically significant (P less than .05) decrease in systolic and mean arterial pressure was noted during the infusion. Complications included burning at the IV infusion site in four patients; the discomfort was relieved in three cases by reducing the rate of infusion to 20 mg/min. Seizures occurred in two patients during the infusion, requiring the additional use of diazepam or phenobarbital. Administration of a loading phenytoin dose by constant IV infusion is an effective means for achieving therapeutic levels quickly.

Cutaneous abscesses: natural history and management in an outpatient facility.

This study investigated the natural history and treatment of cutaneous abscesses in an outpatient setting. Incision, drainage, aerobic and anaerobic cultures were done on all 78 patients entered in the study. Tenderness and fluctuance were noted in more than 80% of the patients; erythema and induration in more than 60%. Forty-one percent of all abscesses were in the anogenital region. Forty-two percent of cultured abscesses grew aerobes exclusively, 28% grew anaerobes exclusively, and 27% grew a mixture of aerobes and anaerobes. The predominant aerobic organisms were Staphylococcus and Streptococcus, which were mostly isolated from the head/neck, extremities, and axillary regions. The predominant anaerobic organisms were Peptococcus and Bacteroides, which were primarily isolated from the anogenital regions. Nearly 60% of the patients returned for reevaluation. They were equally divided between those patients taking antibiotics and those not on antibiotics. However, all patients were clinically improved.

High carboxyhemoglobin level without acute or chronic findings.

The clinical effects of carbon monoxide in humans have been well studied and described. Carboxyhemoglobin levels usually correlate with the degree of symptomatology; however, some investigators have noted that there may be a wide disparity between absolute carboxyhemoglobin levels and clinical status. A case is reported here of a young man with a potentially lethal level of carbon monoxide who developed neither significant symptomatology nor long-term sequelae. Until a more sensitive indicator of clinical outcome is found, clinicians must rely on carboxyhemoglobin levels and clinical history and examination to make treatment decisions, realizing that clinical presentation and absolute carboxyhemoglobin levels may correlate poorly.

Transcutaneous cardiac pacing: determination of myocardial injury in a canine model.

Transcutaneous cardiac pacing holds promise as the initial cardiac pacing technique for emergency patients. Determination of the extent of myocardial injury associated with the use of commercial transcutaneous pacemaker devices has been limited. This study was undertaken to document electrocardiographic, enzymatic, and histologic changes following transcutaneous pacing. Ten mongrel dogs were paced with a transcutaneous cardiac pacemaker for 30 minutes. Electrical pulses of 100 mA lasting 20 ms each were delivered at a rate of 80/min via cutaneous electrodes on the anterior and posterior thorax. Myocardial damage was assessed by serial electrocardiograms (ECGs), serial creatine kinase (CK) determinations with myocardial band (MB) fractionation, and gross and microscopic pathologic examination. Double blind reading of the ECGs showed no significant changes after pacing. CK levels peaked an average of 78 units over baseline levels at 4 hours; however, there was no rise in the CK MB fraction. Pathologic examination revealed micro-infarcts adjacent to intramural vessels in 5 animals, but no clinically significant myocardial injury in the 10 dogs. The absence of enzymatic, cardiographic, and clinically significant pathologic findings was statistically significant (P less than .05). Transcutaneous pacing at low currents and for short periods appears to be a safe technique. This pacing technique deserves further evaluation, and may hold promise as a clinical tool during resuscitation.

Pilot study on disposition and pain relief after i.m. administration of meperidine during the day or night.

Two groups (four patients each) of sickle cell anemia patients with severe pain were studied. One group comprised patients admitted to emergency unit in the morning (5:40 to 9:15) and the other patients admitted in the evening (18:53 to 22:50). All patients received intramuscular meperidine (1.5 mg/kg). Pain intensity and pain relief were followed for 4 h; blood samples were taken up to 6 h after drug administration. Significant differences in drug disposition were found between the day and night groups, as the elimination half-life was 46% shorter during the night and the total serum clearance was 70% greater during the night. Whereas a positive correlation was found between drug concentration and pain relief for the day group, no such correlation was found for th night group. Even though peak concentrations were higher during the night, analgesia was lower. This pilot study suggests that much higher meperidine doses might be required during the night to achieve equieffective analgesia.

Male sexual assault.

Reported cases of sexual assault in the United States increased 21% from 1974 to 1978. Recent literature discusses the medical, legal, and psychological management of the female sexual assault victim, but little has been written regarding appropriate management of male sexual assault. Twenty-nine male sexual assault victims were examined at University Hospital from 1976 to 1980. This study reviews evidence of genital and extragenital trauma and the percentage of those requiring gonorrhea prophylaxis. It further studies the background and characteristics of the sexual assault victim, characterization of the assailant, as well as the details and time of the assault. Information concerning male sexual assault and the unique problems associated with this group is scarce. This study is intended to aid in the development of an effective protocol in dealing with this group of patients and to sensitize physicians to this group of patients.