Impact of efavirenz on hormone-positive breast cancer survival in women living with HIV.

Women living with HIV and breast cancer have poorer survival than HIV-negative women. Efavirenz-estrogen interactions are documented; however, the survival impact is unknown. Survival between women with estrogen-receptor positive breast cancer taking efavirenz (n = 38) and nonefavirenz regimens (n = 51) were compared. The 5-year overall-survival was 48.9% [95% confidence interval (CI) 33.0-72.2 and 51.1% (95% CI 34.0-76.8)] in the efavirenz and nonefavirenz groups, respectively suggesting efavirenz is unlikely driving poorer survival in women living with HIV and estrogen-receptor positive breast cancer.

The Miraculous Pale Blue Dot.

On october 13, 2021, Star Trek's Captain James Tiberius Kirk, in the guise of 90-year-old actor William Shatner, rode aboard a Blue Origin rocket ship 67 miles to the edge of space. He experienced about 3 minutes of weightlessness and was able to observe the Earth from a perspective few have had the privilege to undergo. From his elevated vantage point, he was able to see how really thin the Earth's atmosphere is and he could catch a glimpse of the dark enormity of the rest of the surrounding universe. He said that he was struck by the vulnerability of the Earth and the relative sliver of the atmosphere.

Resting Respiratory Resistance in Female Teenage Athletes With and Without Exercise-Induced Laryngeal Obstruction.

OBJECTIVE: Exercise-induced laryngeal obstruction (EILO) occurs with paradoxical vocal fold motion or supraglottic collapse during moderate to vigorous exercise. Previously, Gallena et al (2015) reported lower-than-normal inspiratory (Ri) and expiratory (Re) resistances during resting tidal breathing (RTB) in female teenage athletes with EILO. This study aimed to replicate that unexpected result. METHOD: The Airflow Perturbation Device measured Ri and Re during three 1-minute trials of RTB in 16 teenage female athletes with EILO and 16 sex-, age-, and height-matched controls. Multiple linear regression examined group, age, height, and weight as predictors of Ri and Re. RESULTS: Ri and Re tended to be lower in the EILO group than the control group [Ri: F(1,30) = 3.58, P = 0.068, d = 0.686; Re: F(1,30) = 3.28, P = 0.080, d = 0.640], but there was no statistically significant difference in the overall effect [F(2,29) = 1.75, P = 0.192]. After one outlier for Re from the EILO group and her matched control were removed, the overall difference was statistically significant, F(2,27) = 3.38, P = 0.049, with Re primarily contributing to the difference [Ri: F(1,28) = 3.66, P = 0.066, d = 0.719; Re: F(1,28) = 5.69, P = 0.024, d = 0.899]. CONCLUSION: These results did not replicate the robust differences found previously between Ri and Re during RTB in teenage girls with and without EILO, but the results trended in the same direction and met criterion for statistical significance once an outlier was removed from analysis. Overall, the observation that resting respiratory resistances were lower in most teenage girls with EILO suggests that reduced tone of the laryngeal and/or lower airways may predispose young athletes to EILO.

Comparison of expiratory isovolume pressure-flow curves with the stop-flow versus the esophageal-balloon method.

BACKGROUND: Expiratory isovolume pressure-flow curves allow determination of flow limitation and airway resistance, but obtaining an isovolume pressure-flow curve requires placing an esophageal balloon. The stop-flow method of obtaining isovolume pressure-flow curves is easy and noninvasive. OBJECTIVE: To compare the stop-flow and esophageal-balloon methods by measuring the differences between the pressures and flows at which flow limitation first occurs. METHODS: In 5 healthy subjects we used the esophageal-balloon method and the stop-flow method at 25%, 50%, and 75% of vital capacity (VC), and constructed isovolume pressure-flow curves showing the pressure at which the flow became limited during forced expiration. RESULTS: The mean calculated pleural pressure at flow limitation with the stop-flow method was 2.7 times and 1.6 times that via the esophageal-balloon method at 25% of VC and 50% of VC, respectively. The maximum flow at flow-limitation with the stop-flow technique was 0.7 times and 0.6 times that via the esophageal-balloon method at 25% of VC and 50% of VC, respectively. We also calculated the resistance (the inverse of the slope of the line to the point of flow limitation), but there were large variations in the resistance values, so there was no statistically significant relationship between the stop-flow and esophageal-balloon methods. CONCLUSION: The stop-flow method showed potential to noninvasively obtain isovolume pressure-flow curves.

Innovation Is Tied to Optimism.

"At the height of laughter, the universe is flung into a kaleidoscope of new possibilities."-Jean Houston.

Getting Past the Know-It-All Stage.

A little knowledge can be a dangerous thing. Most of us have heard of this admonition, and it applies directly to engineering education. It turns out that people who know just a little about a subject greatly overestimate their understanding and abilities. "The Dunning-Kruger effect is a cognitive bias in which people wrongly overestimate their knowledge or ability in a specific area. This tends to occur because a lack of self-awareness prevents them from accurately assessing their own skills" [5].

Best If Used by Date.

We have likely all seen the dates stamped on food packages in the United States that say "Best if used by…" or "Sell by …" or some other phrase that suggests that the food item is not to be consumed after the date specified. It is not really clear by the phrase used if the food item becomes poison after this date, or if the food quality declines after this date, or if the date is just a convenience for the seller to move the product. There is a great deal of confusion about what to do with the product after the date given. Should it be thrown away or can it still be consumed safely but with some degradation of its quality?

Harmonicas.

It is easy for me to imagine life without harmonicas, but for my parents' generation, harmonicas were as common as rain. They were small and easy to fit in a shirt pocket or kit bag, and, whenever an idle moment presented itself, out came the harmonica to render a slightly reedy version of a well-known song: songs like "Red River Valley," "You Are My Sunshine," or "Tennessee Waltz." They were not far from the lips of anyone who played a harmonica.

Ethics in the Era of Artificial Intelligence.

Ethics can be interesting and fascinatingly compelling because of the subtle natures of its solutions in ambiguous situations. Articles on ethical issues and college courses on ethics rarely present answers to the questions that are posed. That is because ethical responses are highly situational and depend a lot on commonly accepted, but not codified, beliefs, and attitudes.

Consciousness in Animals.

Are humans the only species with a sense of consciousness? This question has intrigued me for most of my life. Having kept pets and livestock animals, and observed wild animals from both near and far, I have often wondered just how much they know about their surroundings and their place in it. Do they know how to reason out answers to questions important to them? Are they aware of the consequences of their actions? Can they anticipate what other animals, including those of close kin and other, more remote species, are likely to do in certain situations? Can they see themselves inside their minds, if they do, indeed, have minds? Do they dream?

Collateral Learning.

Students take engineering courses to learn techniques for solving problems. Thus, most engineering courses taken by undergraduate students are highly technical in nature. But, there are many additional techniques and skills that can be learned along the way. Other types of knowledge can also be incorporated into engineering science courses without diminishing the value of the engineering techniques being taught. These other skills, of an ancillary nature, can improve the value of a course to future engineers. This writing is a description of collateral learning that took place in my Transport Design course and, to a lesser extent, my Introduction to Electronic Design course.

School Security?

"Schools rethink security training" was the headline on page 1 of the 30 December 2019 issue of The Baltimore Sun daily newspaper. The accompanying article went on to explain that Maryland school students felt unsafe at school. Students on average rated their physical safety at 3.5 and emotional safety at 5.4, each on a scale of 1 to 10, with 10 being the best score. Many students gave their physical safety scores at 1 out of 10. And this is despite active shooter drills that are meant to teach them what to do if there is a violent confrontation, and in which they have all had to participate.

A War at All Costs?

War between the two worlds Eminiar VII and Vendikar had gone on for 500 years with no cessation in sight. This war was conducted by computer simulation, so that a virtual hit on one planet was retaliated by a computer-generated strike on the other. This avoided the large-scale death and destruction normally suffered during real wartime. To compensate for a war of this surgical nature, a segment of the population of a virtually stricken planet had to be assigned to die in disintegration chambers once the planet was targeted. People dutifully reported to these chambers once their fates were assigned. This was the basis of the episode titled "A Taste of Armageddon" of season one of the original Star Trek television series.

Short-Term Intensive Therapy and Outcomes for Athletes With Paradoxical Vocal Fold Motion Disorder.

Purpose The aim of the study was to develop a treatment for athletes with paradoxical vocal fold motion disorder (PVFMD) based on exercise physiology and learning theory principles and administer it over a preestablished time frame. Method A prospective, repeated-measures, within-subject group design was used. Eleven adolescent/teen athletes diagnosed with PVFMD via laryngoscopy received short-term intensive (STI) therapy. Eight of the athletes returned for extended follow-up. Changes in postexercise inspiratory ( R i) and expiratory ( R e) resistances and Modified Borg Dyspnea Scale (MBDS) ratings collected at baseline were compared immediately posttreatment and at extended follow-up. Dyspnea Index scores were collected at baseline and at extended follow-up. Two no-treatment control athletes with PVFMD participated in two exercise challenges-baseline and 6 weeks later. Results Immediately after STI therapy, athletes attained significant improvement in R i, R e, and MBDS ratings. These changes were maintained at extended follow-up as well as a significant change in Dyspnea Index scores. The 2 control athletes who were reassessed 6 weeks after baseline experienced negative changes in postexercise R i and MBDS ratings. Conclusion STI therapy that incorporated individuality, specificity, and variable practice effectively changed outcome measures posttreatment with further improvement observed at extended follow-up. These results provide preliminary evidence for STI therapy for PVFMD.

Testing limits to airflow perturbation device (APD) measurements.

BACKGROUND: The Airflow Perturbation Device (APD) is a lightweight, portable device that can be used to measure total respiratory resistance as well as inhalation and exhalation resistances. There is a need to determine limits to the accuracy of APD measurements for different conditions likely to occur: leaks around the mouthpiece, use of an oronasal mask, and the addition of resistance in the respiratory system. Also, there is a need for resistance measurements in patients who are ventilated. METHOD: Ten subjects between the ages of 18 and 35 were tested for each station in the experiment. The first station involved testing the effects of leaks of known sizes on APD measurements. The second station tested the use of an oronasal mask used in conjunction with the APD during nose and mouth breathing. The third station tested the effects of two different resistances added in series with the APD mouthpiece. The fourth station tested the usage of a flexible ventilator tube in conjunction with the APD. RESULTS: All leaks reduced APD resistance measurement values. Leaks represented by two 3.2 mm diameter tubes reduced measured resistance by about 10% (4.2 cmH2O.sec/L for control and 3.9 cm H2O.sec/L for the leak). This was not statistically significant. Larger leaks given by 4.8 and 6.4 mm tubes reduced measurements significantly (3.4 and 3.0 cm cmH2O.sec/L, respectively). Mouth resistance measured with a cardboard mouthpiece gave an APD measurement of 4.2 cm H2O.sec/L and mouth resistance measured with an oronasal mask was 4.5 cm H2O.sec/L; the two were not significantly different. Nose resistance measured with the oronasal mask was 7.6 cm H2O.sec/L. Adding airflow resistances of 1.12 and 2.10 cm H2O.sec/L to the breathing circuit between the mouth and APD yielded respiratory resistance values higher than the control by 0.7 and 2.0 cm H2O.sec/L. Although breathing through a 52 cm length of flexible ventilator tubing reduced the APD measurement from 4.0 cm H2O.sec/L for the control to 3.6 cm H2O.sec/L for the tube, the difference was not statistically significant. CONCLUSION: The APD can be adapted for use in ventilated, unconscious, and uncooperative patients with use of a ventilator tube and an oronasal mask without significantly affecting measurements. Adding a resistance in series with the APD mouthpiece has an additive effect on resistance measurements, and can be used for qualitative calibration. A leak size of at least the equivalent of two 3.2 mm diameter tubes can be tolerated without significantly affecting APD measurements.

Human subject testing of leakage in a loose-fitting PAPR.

Leakage from loose-fitting PAPRs (powered air-purifying respirators) can compromise the safety of wearers. The Martindale Centurion MAX multifunction PAPR is a loose-fitting PAPR that also incorporates head, eye, and ear protection. This respirator is used in mines where coal dust usually is controlled by ventilation systems. Should the respirator be depended on for significant respiratory protection? Ten human volunteers were asked to wear the Centurion MAX inside a fog-filled chamber. Their inhalation flow rates were measured with small pitot-tube flowmeters held inside their mouths. They were video imaged while they breathed deeply, and the points at which the fog reached their mouths were determined. Results showed that an average of 1.1 L could be inhaled before contaminated air reached the mouth. As long as the blower purges contamination from inside the face piece during exhalation, the 1.1 L acts as a buffer against contaminants leaked due to overbreathing of blower flow rate.

Black and White and Shades of Gray [State of the Art].

"Moderation in all things" is a popular saying that many of us have heard all our lives. Still, a good number of people seem to have forgotten the sentiment behind this advice. Instead of looking for the good that exists within the bad and the bad that dwells within the good, people are choosing to line up behind one extreme or another. Nuances are being ignored in favor of strong positions on either side of the middle. This has led inevitably to polarization, partisanship, and balkanization in our society. For some reason, moderation has been forgotten.

A Rapid, Handheld Device to Assess Respiratory Resistance: Clinical and Normative Evidence.

INTRODUCTION: Following reports of respiratory symptoms among service members returning from deployment to South West Asia (SWA), an expert panel recommended pre-deployment spirometry be used to assess disease burden. Unfortunately, testing with spirometry is high cost and time-consuming. The airflow perturbation device (APD) is a handheld monitor that rapidly measures respiratory resistance (APD-Rr) and has promising but limited clinical data. Its speed and portability make it ideally suited for large volume pre-deployment screening. We conducted a pilot study to assess APD performance characteristics and develop normative values. MATERIALS AND METHODS: We prospectively enrolled subjects and derived reference equations for the APD from those without respiratory symptoms, pulmonary disease, or tobacco exposure. APD testing was conducted by medical technicians who received a 10-min in-service on its use. A subset of subjects performed spirometry and impulse oscillometry (iOS), administered by trained respiratory therapists. APD measures were compared with spirometry and iOS. RESULTS: The total study population included 199 subjects (55.8% males, body mass index 27.7 ± 6.0 kg/m2, age 49.9 ± 18.7 yr). Across the three APD trials, mean inspiratory (APD-Ri), expiratory (APD-Re), and average (APD-Ravg) resistances were 3.30 ± 1.0, 3.69 ± 1.2, and 3.50 ± 1.1 cm H2O/L/s. Reference equations were derived from 142 clinically normal volunteers. Height, weight, and body mass index were independently associated with APD-Ri, APD-Re, and APD-Ravg and were combined with age and gender in linear regression models. APD-Ri, APD-Re, and APD-Ravg were significantly inversely correlated with FEV1 (r = -0.39 to -0.42), FVC (r = -0.37 to -0.40), and FEF25-75 (r = -0.31 to -0.35) and positively correlated with R5 (r = 0.61-0.62), R20 (r = 0.50-0.52), X5 (r = -0.57 to -0.59), and FRES (r = 0.42-0.43). Bland-Altman plots showed that the APD-Rr closely approximates iOS when resistance is normal. CONCLUSION: Rapid testing was achieved with minimal training required, and reference equations were constructed. APD-Rr correlated moderately with iOS and weakly with spirometry. More testing is required to determine whether the APD has value for pre- and post-deployment respiratory assessment.

Change is necessary in a biological engineering curriculum.

Success of a Biological Engineering undergraduate educational program can be measured in a number of ways, but however it is measured, a presently successful program can translate into an unsuccessful program if it cannot adjust to different conditions posed by technical advances, student characteristics, and academic pressures. Described in this paper is a Biological Engineering curriculum that has changed significantly since its transformation from Agricultural Engineering in 1993. As a result, student numbers have continued to climb, specific objectives have emerged, and unique courses have been developed. The Biological Resources Engineering program has evolved into a program that emphasizes breadth, fundamentals, communications skills, diversity, and practical engineering judgment.

Maximum static inspiratory and expiratory pressures with different lung volumes.

BACKGROUND: Maximum pressures developed by the respiratory muscles can indicate the health of the respiratory system, help to determine maximum respiratory flow rates, and contribute to respiratory power development. Past measurements of maximum pressures have been found to be inadequate for inclusion in some exercise models involving respiration. METHODS: Maximum inspiratory and expiratory airway pressures were measured over a range of lung volumes in 29 female and 19 male adults. A commercial bell spirometry system was programmed to occlude airflow at nine target lung volumes ranging from 10% to 90% of vital capacity. RESULTS: In women, maximum expiratory pressure increased with volume from 39 to 61 cmH2O and maximum inspiratory pressure decreased with volume from 66 to 28 cmH2O. In men, maximum expiratory pressure increased with volume from 63 to 97 cmH2O and maximum inspiratory pressure decreased with volume from 97 to 39 cmH2O. Equations describing pressures for both sexes are: Pe/Pmax = 0.1426 Ln( %VC) + 0.3402 R2 = 0.95 Pi/Pmax = 0.234 Ln(100 - %VC) - 0.0828 R2 = 0.96 CONCLUSION: These results were found to be consistent with values and trends obtained by other authors. Regression equations may be suitable for respiratory mechanics models.