Effects of CO2-induced pH reduction on the exoskeleton structure and biophotonic properties of the shrimp Lysmata californica.

The anticipated effects of CO2-induced ocean acidification on marine calcifiers are generally negative, and include dissolution of calcified elements and reduced calcification rates. Such negative effects are not typical of crustaceans for which comparatively little ocean acidification research has been conducted. Crustaceans, however, depend on their calcified exoskeleton for many critical functions. Here, we conducted a short-term study on a common caridean shrimp, Lysmata californica, to determine the effect of CO2-driven reduction in seawater pH on exoskeleton growth, structure, and mineralization and animal cryptic coloration. Shrimp exposed to ambient (7.99 ± 0.04) and reduced pH (7.53 ± 0.06) for 21 days showed no differences in exoskeleton growth (percent increase in carapace length), but the calcium weight percent of their cuticle increased significantly in reduced pH conditions, resulting in a greater Ca:Mg ratio. Cuticle thickness did not change, indicating an increase in the mineral to matrix ratio, which may have mechanical consequences for exoskeleton function. Furthermore, there was a 5-fold decrease in animal transparency, but no change in overall shrimp coloration (red). These results suggest that even short-term exposure to CO2-induced pH reduction can significantly affect exoskeleton mineralization and shrimp biophotonics, with potential impacts on crypsis, physical defense, and predator avoidance

Using area health education centers to promote interest in rural practice

Introduction: In the USA, area health education centers (AHECs) work to recruit and educate students to serve in medically underserved communities, primary care, and rural settings. One important aspect of their work is connecting students with rural clinical experiences. Within these experiences, AHECs incorporate a community health/socioeconomic experience within the family medicine clerkship that may not be as prevalent in the standard family medicine clerkship experiences. The purpose of the study was to assess the relationship between AHEC-sponsored family medicine clerkships with a self-reported intent to practice in a rural setting upon graduation. Methods: The study compared third-year medical students with the Indiana University School of Medicine, which participated in AHEC-sponsored family medicine clerkships to the standard family medicine clerkship. Following the 4-week clerkship, students were asked to report their intent to work in a rural setting using a five-point Likert scale. A χ2 test was used to determine the association of AHEC sponsorship, clerkship site location (rural/urban) and intent to practice in a rural setting. Results: The study consisted of 587 students. There was a statistically significant association between self-reported intent and rural clerkship site, χ2 (1, N=587)=6.542, p=0.01. Furthermore, 21.6% (n=25) of students with a rural clerkship experience reported a greater intent compared to 12.3% (n=58) of students with non-rural clerkship experience. Conclusions: The study confirmed a significantly positive association between participation in medical clerkship experiences in a rural primary care setting and the intent to practice in a rural setting upon graduation. The results also support the potential value-added benefits through academic–community partnerships with AHECs, family medical and other primary care specialty clerkship programs may perhaps succeed in increasing student interest in pursuing a practice serving in rural communities upon graduation

Impact of Flower Harvesting on the Salt Marsh Plant \u3cem\u3eLimonium carolinianum\u3c/em\u3e

Because of the potentially detrimental effects of seed production on adult survivorship and growth, moderate flower harvesting may have little negative impact on population growth of long-lived perennial plants such as Limonium carolinianum (Walter) Britton. We examined this by collecting data on survivorship, growth, and fecundity of an unharvested population over a period of 5 years and conducted a controlled experiment to examine the effect of harvesting on adult survivorship and growth over a 3-year period. Data were summarized in the form of a stage structured matrix population model with a stochastic element that incorporated year-to-year variation in transition probabilities. Contrary to our original hypothesis, we found that preventing seed set through removal of flowers did not increase adult survivorship or growth. By determining the harvest level that reduced population growth rate to 1.0, we estimated the maximum sustainable harvest level to be 16%, a value that is approximately half that of reported harvest levels on accessible marshes in the study area. In spite of this, the reported harvest levels are unlikely to drive local populations to extinction in the foreseeable future. Providing the adult population size is \u3e100 and harvest levels are \u3c90%, time to local extinction will exceed 100 years. This is a function of the very high survivorship of adults in this species and the fact that harvesting has no negative impact on adult survivorship or growth. However, because of the long preadult phase in this species (8–9 years) and the fact that fecundity of young adults is low, recovery from overharvesting is extremely slow. Adult population size can be reduced to 25% of its original value in 7 years at high harvest levels, but it will take 34 years on average to recover once harvesting is terminated

Does an AHEC-sponsored Clerkship Experience Strengthen Medical Students’ Intent to Provide Care for Medically Underserved Patients?

The mission of Area Health Education Centers (AHECs) is to recruit and educate students to serve as practicing health care professionals in rural, primary care, and medically underserved communities. We sought to determine if participation in an AHEC-sponsored family medicine clerkship experiences during medical school are significantly associated with a self-reported intent to practice primary care in a medically underserved environment upon graduation. The study was a prospective cohort study comparing third-year family medicine students with the Indiana University School of Medicine who participated in either an AHEC-sponsored family medicine clerkship to those who completed their required family medicine clerkship outside of the AHEC setting. Following the 160-h clinical clerkship, all students completed a mandatory, electronic survey and were asked to self-report their intent to the following question: “Which of the following statements best describes the impact of the family medicine clerkship on your intention to provide care to underserved patients when you complete residency training?” The question was integrated into a mandatory post-clerkship evaluation form required by the Indiana University School of Medicine, Department of Family Medicine. A Chi square test of independence as well as a multivariate logistic regression analysis was used to determine the independent association of AHEC clerkship participation and reported intent. A total of 1138 students completed the survey. There were not significant differences in age, gender, race, and ethnicity between students that completed an AHEC clerkship and those that did not. After adjusting for gender, race, and ethnicity, AHEC participants were significantly more likely to report an intention to practice primary care in a medically underserved setting upon graduation. Female students were found to be 1.2–3.4 times as likely to report increased intent compared to male students (95 % CI 1.241–3.394). Participation in an AHEC-supported clerkship was associated with a significant increase in self-reported intent to practice primary care in a medically underserved setting. Additional research is required to determine if participation and/or reported intent are predictive of practice selection after graduation

Medical abortion with mifepristone and vaginal misoprostol between 64 and 70 days' gestation.

ObjectiveTo evaluate outcomes with mifepristone 200 mg orally followed 24-48 h later by misoprostol 800 mcg vaginally for medical abortion at 64-70 days of gestation.Study designWe reviewed electronic databases and medical records for medical abortion cases at 64-70 days' gestation at British Pregnancy Advisory Service clinics in England and Wales from May 2015 through October 2016. Women selected in-office follow-up or self-evaluation of abortion outcome using a checklist along with low-sensitivity urine pregnancy testing. We excluded cases in which we could not locate records and when women did not proceed with medical abortion, did not use misoprostol following mifepristone if abortion had not occurred and did not attend a scheduled follow-up assessment. We analyzed demographic characteristics, treatment outcomes and significant adverse events. We defined treatment success as complete abortion without surgical evacuation and without continuing pregnancy.ResultsOf 2743 cases identified, we could not locate 40 charts and excluded 30 cases, leaving a final sample of 2673. Overall, 2538 (94.9%, 95% CI 94.1-95.8) women had a successful medical abortion. Reasons for failure included continuing pregnancy (n=90, 3.4%, 95% CI 2.7-4.1), retained nonviable pregnancy (n=2, 0.1%, 95% CI 0-0.2) and incomplete abortion (n=43, 1.6%, 95% CI 1.1-2.1). Of those with continuing pregnancies, 81 underwent a uterine aspiration and 9 opted to continue the pregnancy. Thirty-five (1.3%, 95% CI 0.9-1.7) women had significant adverse events; 16 (0.6%, 95% CI 0.3-0.9) underwent an in-hospital aspiration. Pelvic infection (n=4, 0.2%) and transfusion (n=1, 0.03%) occurred rarely.ConclusionMedical abortion from 64 to 70 days with mifepristone and vaginal misoprostol is effective with a low rate of serious adverse events.ImplicationsMedical abortion between 64 and 70 days of gestation may be offered on an outpatient basis using mifepristone and vaginal misoprostol. Service provision without an in-person follow-up is feasible. Not all women with a continuing pregnancy after medical abortion treatment opt to have an aspiration procedure

Acute effects of ingesting Java Fit™ energy extreme functional coffee on resting energy expenditure and hemodynamic responses in male and female coffee drinkers

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to examine the effects of a functional coffee beverage containing additional caffeine, green tea extracts, niacin and garcinia cambogia to regular coffee to determine the effects on resting energy expenditure (REE) and hemodynamic variables.</p> <p>Methods</p> <p>Subjects included five male (26 ± 2.1 y, 97.16 ± 10.05 kg, 183.89 ± 6.60 cm) and five female (28.8 ± 5.3 y, 142.2 ± 12.6 lbs) regular coffee drinkers. Subjects fasted for 10 hours and were assessed for 1 hour prior (PRE) and 3 hours following 1.5 cups of coffee ingestion [JavaFit™ Energy Extreme (JF) ~400 mg total caffeine; Folgers (F) ~200 mg total caffeine] in a double-blind, crossover design. REE, resting heart rate (RHR), and systolic (SBP) and diastolic (DBP) blood pressure was assessed at PRE and 1, 2, and 3-hours post coffee ingestion. Data were analyzed by three-factor repeated measures ANOVA (p < 0.05).</p> <p>Results</p> <p>JF trial resulted in a significant main effect for REE (p < 0.01), SBP (p < 0.01), RER (p < 0.01), and VO₂(p < 0.01) compared to F, with no difference between trials on the RHR and DBP variables. A significant interaction for trial and time point (p < 0.05) was observed for the variable REE. The JF trial resulted in a significant overall mean increase in REE of 14.4% (males = 12.1%, females = 17.9%) over the observation period (p < 0.05), while the F trial produced an overall decrease in REE of 5.7%. SBP was significantly higher in the JF trial; however, there was no significant increase from PRE to 3-hours post.</p> <p>Conclusion</p> <p>Results from this study suggest that JavaFit™ Energy Extreme coffee is more effective than Folgers regular caffeinated coffee at increasing REE in regular coffee drinkers for up to 3 hours following ingestion without any adverse hemodynamic effects.</p

Ultralow phase noise microwave generation with an Er:fiber-based optical frequency divider

We present an optical frequency divider based on a 200 MHz repetition rate Er:fiber mode-locked laser that, when locked to a stable optical frequency reference, generates microwave signals with absolute phase noise that is equal to or better than cryogenic microwave oscillators. At 1 Hz offset from a 10 GHz carrier, the phase noise is below -100 dBc/Hz, limited by the optical reference. For offset frequencies > 10 kHz, the phase noise is shot noise limited at -145 dBc/Hz. An analysis of the contribution of the residual noise from the Er:fiber optical frequency divider is also presented.Comment: 4 pages, 3 figure