Preventing Retained Central Venous Catheter Guidewires: A Randomized Controlled Simulation Study Using a Human Factors Approach.

BACKGROUND: Retained central venous catheter guidewires are never events. Currently, preventative techniques rely on clinicians remembering to remove the guidewire. However, solutions solely relying upon humans to prevent error inevitably fail. A novel locked procedure pack was designed to contain the equipment required for completing the procedure after the guidewire should have been removed: suture, suture holder, and antimicrobial dressings. The guidewire is used as a key to unlock the pack and to access the contents; thereby, the clinician must remove the guidewire from the patient to complete the procedure. METHODS: A randomized controlled forced-error simulation study replicated catheter insertion. We created a retained guidewire event and then determined whether clinicians would discover it, comparing standard practice against the locked pack. RESULTS: Guidewires were retrieved from 2/10 (20%) standard versus 10/10 (100%) locked pack, n = 20, P < 0.001. In the locked pack group, participants attempted to complete the procedure; however, when unable to access the contents, this prompted a search for the key (guidewire). Participants discovered the guidewire within the catheter lumen, recovered it, utilized it to unlock the pack, and finish the procedure. A structured questionnaire reported that the locked pack also improved subjective safety of central venous catheter insertion and allowed easy disposal of the sharps and guidewire (10/10). CONCLUSIONS: The locked pack is an engineered solution designed to prevent retained guidewires. Utilizing forced-error simulation testing, we have determined that the locked pack is an effective preventative device and is acceptable to clinicians for improving patient safety

The nuclear star cluster of the Milky Way

The nuclear star cluster of the Milky Way is a unique target in the Universe. Contrary to extragalactic nuclear star clusters, using current technology it can be resolved into tens of thousands of individual stars. This allows us to study in detail its spatial and velocity structure as well as the different stellar populations that make up the cluster. Moreover, the Milky Way is one of the very few cases where we have firm evidence for the co-existence of a nuclear star cluster with a central supermassive black hole, Sagittarius A*. The number density of stars in the Galactic center nuclear star cluster can be well described, at distances $\gtrsim1$ pc from Sagittarius A*, by a power-law of the form $\rho(r)\propto r^{-\gamma}$ with an index of $\gamma\approx1.8$. In the central parsec the index of the power-law becomes much flatter and decreases to $\gamma\approx1.2$. We present proper motions for more than 6000 stars within 1 pc in projection from the central black hole. The cluster appears isotropic at projected distances $\gtrsim0.5$ pc from Sagittarius A*. Outside of 0.5 pc and out to 1.0 pc the velocity dispersion appears to stay constant. A robust result of our Jeans modeling of the data is the required presence of $0.5-2.0\times10^{6} M_{\odot}$ of extended (stellar) mass in the central parsec of the Galaxy.Comment: To appear in the proceedings of "The Universe under the Microscope - Astrophysics at High Angular Resolution", Journal of Physics:Conference Series (IOP; http://www.iop.org/EJ/conf) This version has been slightly modified (e.g. double-log plot in right hand panel of Figure 5

Integration of robotic surgery into routine practice and impacts on communication, collaboration, and decision making: A realist process evaluation protocol

Background: Robotic surgery offers many potential benefits for patients. While an increasing number of healthcare providers are purchasing surgical robots, there are reports that the technology is failing to be introduced into routine practice. Additionally, in robotic surgery, the surgeon is physically separated from the patient and the rest of the team, with the potential to negatively impact teamwork in the operating theatre. The aim of this study is to ascertain: how and under what circumstances robotic surgery is effectively introduced into routine practice; and how and under what circumstances robotic surgery impacts teamwork, communication and decision making, and subsequent patient outcomes. Methods and design: We will undertake a process evaluation alongside a randomised controlled trial comparing laparoscopic and robotic surgery for the curative treatment of rectal cancer. Realist evaluation provides an overall framework for the study. The study will be in three phases. In Phase I, grey literature will be reviewed to identify stakeholders' theories concerning how robotic surgery becomes embedded into surgical practice and its impacts. These theories will be refined and added to through interviews conducted across English hospitals that are using robotic surgery for rectal cancer resection with staff at different levels of the organisation, along with a review of documentation associated with the introduction of robotic surgery. In Phase II, a multi-site case study will be conducted across four English hospitals to test and refine the candidate theories. Data will be collected using multiple methods: the structured observation tool OTAS (Observational Teamwork Assessment for Surgery); video recordings of operations; ethnographic observation; and interviews. In Phase III, interviews will be conducted at the four case sites with staff representing a range of surgical disciplines, to assess the extent to which the results of Phase II are generalisable and to refine the resulting theories to reflect the experience of a broader range of surgical disciplines. The study will provide (i) guidance to healthcare organisations on factors likely to facilitate successful implementation and integration of robotic surgery, and (ii) guidance on how to ensure effective communication and teamwork when undertaking robotic surgery

Versatility and Stereotypy of Free-Tailed Bat Songs

In mammals, complex songs are uncommon and few studies have examined song composition or the order of elements in songs, particularly with respect to regional and individual variation. In this study we examine how syllables and phrases are ordered and combined, ie “syntax”, of the song of Tadarida brasiliensis, the Brazilian free-tailed bat. Specifically, we test whether phrase and song composition differ among individuals and between two regions, we determine variability across renditions within individuals, and test whether phrases are randomly ordered and combined. We report three major findings. First, song phrases were highly stereotyped across two regions, so much so that some songs from the two colonies were almost indistinguishable. All males produced songs with the same four types of syllables and the same three types of phrases. Second, we found that although song construction was similar across regions, the number of syllables within phrases, and the number and order of phrases in songs varied greatly within and among individuals. Last, we determined that phrase order, although diverse, deviated from random models. We found broad scale phrase-order rules and certain higher order combinations that were highly preferred. We conclude that free-tailed bat songs are composed of highly stereotyped phrases hierarchically organized by a common set of syntactical rules. However, within global species-specific patterns, songs male free-tailed bats dynamically vary syllable number, phrase order, and phrase repetitions across song renditions

Seasonal changes in patterns of gene expression in avian song control brain regions.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Photoperiod and hormonal cues drive dramatic seasonal changes in structure and function of the avian song control system. Little is known, however, about the patterns of gene expression associated with seasonal changes. Here we address this issue by altering the hormonal and photoperiodic conditions in seasonally-breeding Gambel's white-crowned sparrows and extracting RNA from the telencephalic song control nuclei HVC and RA across multiple time points that capture different stages of growth and regression. We chose HVC and RA because while both nuclei change in volume across seasons, the cellular mechanisms underlying these changes differ. We thus hypothesized that different genes would be expressed between HVC and RA. We tested this by using the extracted RNA to perform a cDNA microarray hybridization developed by the SoNG initiative. We then validated these results using qRT-PCR. We found that 363 genes varied by more than 1.5 fold (>log(2) 0.585) in expression in HVC and/or RA. Supporting our hypothesis, only 59 of these 363 genes were found to vary in both nuclei, while 132 gene expression changes were HVC specific and 172 were RA specific. We then assigned many of these genes to functional categories relevant to the different mechanisms underlying seasonal change in HVC and RA, including neurogenesis, apoptosis, cell growth, dendrite arborization and axonal growth, angiogenesis, endocrinology, growth factors, and electrophysiology. This revealed categorical differences in the kinds of genes regulated in HVC and RA. These results show that different molecular programs underlie seasonal changes in HVC and RA, and that gene expression is time specific across different reproductive conditions. Our results provide insights into the complex molecular pathways that underlie adult neural plasticity

Infrared Light Curves of Mira Variable Stars from COBE DIRBE Data

We have used the COBE DIRBE database to derive near- and mid-infrared light curves for a well-defined sample of 38 infrared-bright Mira variable stars, and compared with optical data from the AAVSO. In general, the 3.5 micron and 4.9 micron DIRBE bandpasses provide the best S/N light curves, with S/N decreasing with wavelength at longer wavelengths. At 25 microns, good light curves are only available for ~10 percent of our stars, and at wavelengths >= 60 microns, extracting high quality light curves is not possible. The amplitude of variability is typically less in the near-infrared than in the optical, and less in the mid-infrared than in the near-infrared, with decreasing amplitude with increasing wavelength. On average, there are 0.20 +/- 0.01 magnitudes variation at 1.25 microns and 0.14 +/- 0.01 magnitudes variation at 4.9 micron for each magnitude variation in V. The observed amplitudes are consistent with results of recent theoretical models of circumstellar dust shells around Mira variables. For a few stars in our sample, we find clear evidence of time lags between the optical and maxima of phase ~ 0.05 - 0.13, with no lags in the minima. For three stars, mid-infrared maximum appears to occur slightly before that in the near-infrared,but after optical maximum. We find three examples of secondary maxima in the rising portions of the DIRBE light curves, all of which have optical counterparts in the AAVSO data, supporting the hypothesis that they are due to shocks rather than newly-formed dust layers. We find no conclusive evidence for rapid (hours to days) variations in the infrared brightnesses of these stars.Comment: 16 pages, Astronomical Journal, in press, to be publishe

Conceptualizing handover strategies at change of shift in the emergency department: a grounded theory study

<p>Abstract</p> <p>Background</p> <p>The importance and complexity of handovers is well-established. Progress for intervening in the emergency department change of shift handovers may be hampered by lack of a conceptual framework. The objectives were to gain a better understanding of strategies used for change of shift handovers in an emergency care setting and to further expand current understanding and conceptualizations.</p> <p>Methods</p> <p>Observations, open-ended questions and interviews about handover strategies were collected at a Veteran's Health Administration Medical Center in the United States. All relevant staff in the emergency department was observed; 31 completed open-ended surveys; 10 completed in-depth interviews. The main variables of interest were strategies used for handovers at change of shift and obstacles to smooth handovers.</p> <p>Results</p> <p>Of 21 previously identified strategies, 8 were used consistently, 4 were never used, and 9 were used occasionally. Our data support ten additional strategies. Four agent types and 6 phases of the process were identified via grounded theory analysis. Six general themes or clusters emerged covering factors that intersect to define the degree of handover smoothness.</p> <p>Conclusion</p> <p>Including phases and agents in conceptualizations of handovers can help target interventions to improve patient safety. The conceptual model also clarifies unique handover considerations for the emergency department setting.</p

Device Performance of Emerging Photovoltaic Materials (Version 2)

Following the 1st release of the “Emerging photovoltaic (PV) reports”, the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer-reviewed articles in academic journals since August 2020. Updated graphs, tables, and analyses are provided with several performance parameters, e.g., power conversion efficiency, open-circuit voltage, short-circuit current density, fill factor, light utilization efficiency, and stability test energy yield. These parameters are presented as a function of the photovoltaic bandgap energy and the average visible transmittance for each technology and application and are put into perspective using, e.g., the detailed balance efficiency limit. The 2nd instalment of the “Emerging PV reports” extends the scope toward tandem solar cells and presents the current state-of-the-art in tandem solar cell performance for various material combinations.</p

Device Performance of Emerging Photovoltaic Materials (Version 1)

Emerging photovoltaics (PVs) focus on a variety of applications complementing large scale electricity generation. Organic, dye‐sensitized, and some perovskite solar cells are considered in building integration, greenhouses, wearable, and indoor applications, thereby motivating research on flexible, transparent, semitransparent, and multi‐junction PVs. Nevertheless, it can be very time consuming to find or develop an up‐to‐date overview of the state‐of‐the‐art performance for these systems and applications. Two important resources for recording research cells efficiencies are the National Renewable Energy Laboratory chart and the efficiency tables compiled biannually by Martin Green and colleagues. Both publications provide an effective coverage over the established technologies, bridging research and industry. An alternative approach is proposed here summarizing the best reports in the diverse research subjects for emerging PVs. Best performance parameters are provided as a function of the photovoltaic bandgap energy for each technology and application, and are put into perspective using, e.g., the Shockley–Queisser limit. In all cases, the reported data correspond to published and/or properly described certified results, with enough details provided for prospective data reproduction. Additionally, the stability test energy yield is included as an analysis parameter among state‐of‐the‐art emerging PVs