Dental students' ability to locate emergency equipment-lessons learned from aviation.

PURPOSE: The purpose of this study was to evaluate the dental student's ability to locate medical emergency equipment/items at the University of Michigan School of Dentistry clinic. METHODS: A total of 138 second-year dental students (traditional group) participated in this study as part of a simulation-based medical emergencies rotation course held during the winter term of 2014 and 2015. Without prior training, students were tested on their ability to locate nine predetermined items on the clinic floor using a self-reported checklist. Six months later, a convenience sample of 18 students (novel group) from the same cohort were later trained on their location and retested individually. RESULTS: Of the 138 students tested, only 10.14% students could locate seven of the nine items when compared to 100% in the novel group. Only 5.07% of students in the traditional group could locate all items initially, compared with 72.22% students in the novel group. CONCLUSION: Whilst our students have lecture-based knowledge about medical emergencies, the results of our study identified a gap of knowledge of emergency equipment/item location amongst students. Therefore, an intervention performed with a similar group of second-year dental students supported that proper training may be used to achieve retention of knowledge. Based on our "novel group" results, we have incorporated targeted training in the dental curriculum that leads to students being better prepared in locating emergency equipment/items. This study suggests that other populations, such as faculty or staff, may also benefit from hands-on training.

WOCN Society Position Paper: Avoidable Versus Unavoidable Pressure Ulcers/Injuries.

The issue of whether pressure injuries are avoidable or preventable has been and continues to be an issue of great debate and discussion for many years, and it has significant legal and regulatory implications related to prevention of wounds due to pressure. The following position paper outlines the position of the Wound, Ostomy and Continence Nurses Society (WOCN) on avoidable versus unavoidable pressure injuries. It includes the following information: statement of position, purpose/rationale for the position, definitions of avoidable versus unavoidable pressure injuries, alternative definitions, historical overview, supportive statements from expert opinion and research in the literature, and recommendations for research.

Nitrogen in solar energetic particles: isotopically distinct from solar wind.

Stepwise etching of lunar soil ilmenite grains reveals that the 15N/14N ratio of implanted nitrogen decreases with increasing implantation depth within the ilmenite grains, i.e., with increasing energy of implantation. These results show that N derived from solar energetic particles, NSEP, is enriched in the light isotope, 14N, relative to solar-wind nitrogen, NSW. This is in striking contrast to the neon isotopic record: NeSEP is depleted in the light isotope, 20Ne, relative to NeSW. These data suggest either distinct signatures in the respective solar source regions, or fractionation in the acceleration mechanism(s). However, the observed opposite fractionation trends for light N and Ne isotopes do not agree with model predictions.

Nitrogen isotope abundances in the recent solar wind.

Although lunar crystalline rocks are essentially devoid of nitrogen, the same is not true of the lunar regolith. The nitrogen contents of individual regolith samples (which can be as high as 0.012% by mass) correlate strongly with abundances of noble gases known to be implanted in the lunar surface by solar radiation, indicating that lunar regolith nitrogen is also predominantly of solar origin. The large variability in 15N/14N ratios measured in different regolith samples may thus reflect long-term changes in the isotopic composition of the solar radiation. But attempts to explain these variations have been hampered by the lack of any firm constraint on 15N/14N in the present solar wind. Here we report measurements of nitrogen isotopes from two lunar samples that have had simple (and relatively recent) exposure histories. We find that nitrogen implanted in the lunar surface during the past 10(5) to 5 x 10(7) years has a 15N/14N ratio approximately 40% higher than that in the terrestrial atmosphere, which is substantially lower than most previous estimates. This isotopic signature probably represents the best measure of 15N/14N in the present-day solar wind.

Discovery of an unmelted h-chondrite inclusion in an iron meteorite.

The link between H chondrites and silicate inclusions in group IIE iron meteorites has long been suspected, but direct evidence for a common parentage has remained elusive. The discovery of an unmelted chondritic inclusion in the Techado iron meteorite sheds light on the genetic relation between these two groups, providing clues on the origin of chondritic materials as inclusions in iron meteorites. It is proposed that the complex IIE iron meteorite breccias formed by collisions with several different bodies, followed by deep burial of metal and silicate fragments in the asteroidal megaregolith.

Signatures of the martian atmosphere in glass of the Zagami meteorite.

Isotopic signatures of nitrogen, argon, and xenon have been determined in separated millimeter-sized pockets of shock-melted glass in a recently identified lithology of the meteorite Zagami, a shergottite. The ratio of nitrogen-15 to nitrogen-14, which is at least 282 per mil larger than the terrestrial value, the ratio of xenon-129 to xenon-132 = 2.40, and the argon isotopic abundances match the signatures previously observed in the glassy lithology of the Antarctic shergottite EETA 79001. These results show that the signatures in EETA 79001 are not unique but characterize the trapped gas component in shock-melted glass of shergottites. The isotopic and elemental ratios of nitrogen, argon, and xenon closely resemble the Viking spacecraft data for the martian atmosphere and provide compelling evidence for a martian origin of the two shergottites and, by extension, of the meteorites in the shergottites-nakhlites-chassignites (SNC) group.

Compositional trends in rock-forming elements of comet Halley dust.

The VEGA 1 and 2 spacecraft flew by comet P/Halley in 1986 carrying, among other instruments, two mass spectrometers to measure the elemental composition of dust particles emitted from the comet. Most particles seem to be a mixture of silicates of variable magnesium-iron composition and organic matter. Comprehensive study of data and consideration of the mass of dust particles reveal cometary grains of "unusual" composition: magnesium-rich and iron-rich particles. Magnesium-rich particles are most likely magnesium carbonates, which could not have formed under conditions of equilibrium condensation but rather require formation by aqueous alteration. The composition of the iron-rich particles can also be related to secondary processes in the comet.

Organic compounds in the Forest Vale, H4 ordinary chondrite.

We have analyzed the H4 ordinary chondrite Forest Vale for polycyclic aromatic hydrocarbons (PAHs) using two-step laser mass spectrometry (L2MS) and for amino acids using a standard chromatographic method. Indigenous PAHs were identified in the matrices of freshly cleaved interior faces but could not be detected in pulverized silicates and chondrules. No depth dependence of the PAHs was found in a chipped interior piece. Amino acids, taken from the entire sample, consisted of protein amino acids that were nonracemic, indicating that they are terrestrial contaminants. The presence of indigenous PAHs and absence of indigenous amino acids provides support for the contention that different processes and environments contributed to the synthesis of the organic matter in the solar system.

Erythropoietin induces p21ras activation and p120GAP tyrosine phosphorylation in human erythroleukemia cells.

Erythropoietin is the major regulator of the proliferation and differentiation of erythroid precursors, but little is known about its molecular mechanism of action. Using a human erythroleukemic cell line (HEL), we investigated whether p21ras is involved in erythropoietin signal transduction. We found that stimulation of HEL cells with erythropoietin induces a 5-fold increase in the amount of GTP bound to the endogenous p21ras. This effect is dose-dependent and occurs very rapidly. We also observed that erythropoietin causes tyrosine phosphorylation of several proteins in a time-dependent manner that correlates with the p21ras activation. Moreover, inhibition of tyrosine kinases by genistein totally prevents the erythropoietin-induced accumulation of a p21ras.GTP complex. By using an antiserum against the GTPase-activating protein, we found that p120GAP is rapidly phosphorylated in tyrosine in response to erythropoietin. Furthermore, the ability of a lysate from erythropoietin-stimulated HEL cells to induce in vitro hydrolysis of GTP bound to p21ras was strongly reduced. These results demonstrate that activation of p21ras is an early event in the erythropoietin signal transduction pathway, and they suggest that accumulation of the p21ras.GTP complex may be triggered by inhibition of GTPase-activating protein activity.

Epinephrine suppresses rap1B.GAP-activated GTPase activity in human platelets.

Lysate from quiescent platelets promotes rapid hydrolysis of [gamma-32P]GTP bound to rap1B. Various platelet agonists, including platelet-activating factor, phorbol 12,13-dibutyrate, alpha-thrombin, epinephrine, ADP, and iloprost, that affect platelet metabolism by different signal transduction pathways were used to stimulate intact platelets and study their effects on rap1B.GAP-activated GTPase activity (GAP, GTPase-activating protein). Only epinephrine was found to dramatically decrease not only the rate but also the amount of hydrolysis of rap1B-bound GTP activated by rap1B.GAP. This effect was dose dependent and occurred rapidly. The suppression of GTPase activity was specific for rap1B.GAP in that ras.GAP- and rap2B.GAP-activated GTPase activity were not affected by epinephrine stimulation. This effect appears to be mediated by the alpha 2-adrenergic receptor, as evidenced by a similar suppression of GTPase activity by stimulating platelets with the synthetic alpha 2-adrenergic receptor agonist UK14304 (bromoxidine). Furthermore, the selective alpha 2-adrenergic receptor antagonist yohimbine blocked the suppression of GTPase activity expressed in epinephrine-stimulated cell lysates. No apparent changes in the patterns of protein expression or tyrosine phosphorylation were observed. Although the migration characteristics upon anion-exchange chromatography of rap1B.GAP and ras.GAP activities were unaffected by epinephrine stimulation, the specific activity of rap1B.GAP was noticeably decreased with 250 and 500 microM epinephrine. These results suggest a possible role for rap1B and rap1B.GAP in epinephrine-stimulated signal transduction.

[Temporomandibular joint ankylosis: the problem of restoration]. / Alethes agkylose tes krotaphognathikes arthroses: to problema tes apokatastases.

Restoration of normal motion and function in patients with temporomandibular joint ankylosis, has been a difficult goal to achieve. According to the experience of the authors early mobilization and physiotherapy, without lining the joint with intermediate materials, is effective for treatment of TMJ ankylosis.

[Indications for tracheostomy in patients with oral and maxillofacial problems]. / Endeixeis tracheistomias se astheneis me gnathocheirourgiko prolema.

Tracheostomy encounters in several conditions in oral and maxillofacial surgery. Upper airway obstruction is the most common, often occurring secondary to maxillofacial trauma. Obstruction may also be caused by neoplasms of the oral cavity, by hematoma, oedema, abscess or allergy. In this paper we discuss the indications for tracheostomy in patients with oral and maxillofacial problems and the complications that may occur in patients from the procedure itself.

[Emergency care in maxillofacial injuries]. / Epeigousa antimetopise ton kakoseon tes gnathoprosopikes choras.

We present the methodology of the emergency care in maxillofacial injuries, mainly the preservation of vital functions and the control of the general condition of the patient. Definitive care will follow the emergency care measures.