The Ongoing Syrian Arab Republic Health Care Crisis.

Prior to the Syrian civil war, access and delivery of health care and health care information over the past 4 decades had steadily improved. The life expectancy of the average Syrian in 2012 was 75.7 years, compared to 56 years in 1970. As a result of the civil war, this trend has reversed, with the life expectancy reduced by 20 years from the 2012 level. The Syrian government and its allies have specifically targeted the health care infrastructure not under government control. (Disaster Med Public Health Preparedness. 2018;12:23-25).

Fluid structure interaction model analysis of cerebrospinal fluid circulation in patients with continuous-flow left ventricular assist devices.

PURPOSE: The current 1-dimensional fluid structure interaction model (FSI) for understanding cerebrospinal fluid (CSF) circulation requires pulsatility as a precondition and has not been applied to patients with continuous-flow left ventricular assist devices (CF-LVAD) where pulsatility is chronically reduced. Our study aims to characterize the behavior of CSF pressure and flow in patients with CF-LVADs using a computational FSI model. METHODS: Utilizing the computational FSI model, CSF production in choroid plexuses of the 4 ventricles was specified as a boundary condition for the model. The other source of production from capillary ultrafiltrate spaces was accounted for by the mass conservation equation. The primary CSF absorption sites (i.e., arachnoid granulations) were treated as the outlet boundary conditions. We established a low pulse wave to represent patients with a CF-LVAD. RESULTS: From the model, low pulse conditions resulted in a reduction in CSF pressure amplitude and velocity though the overall flow rate was unchanged. CONCLUSIONS: The existing FSI model is not a suitable representation of CSF flow in CF-LVAD patients. More studies are needed to elucidate the role of pulsatility in CSF flow and the compensatory changes in CSF production and absorption that occur in patients with CF-LVADs in whom pulsatility is diminished.

Current State and Future Perspectives of Energy Sources for Totally Implantable Cardiac Devices.

There is a large population of patients with end-stage congestive heart failure who cannot be treated by means of conventional cardiac surgery, cardiac transplantation, or chronic catecholamine infusions. Implantable cardiac devices, many designated as destination therapy, have revolutionized patient care and outcomes, although infection and complications related to external power sources or routine battery exchange remain a substantial risk. Complications from repeat battery replacement, power failure, and infections ultimately endanger the original objectives of implantable biomedical device therapy - eliminating the intended patient autonomy, affecting patient quality of life and survival. We sought to review the limitations of current cardiac biomedical device energy sources and discuss the current state and trends of future potential energy sources in pursuit of a lifelong fully implantable biomedical device.

Ebola outbreak response: the role of information resources and the National Library of Medicine.

The US National Library of Medicine (NLM) offers Internet-based, no-cost resources useful for responding to the 2014 West Africa Ebola outbreak. Resources for health professionals, planners, responders, and researchers include PubMed, Disaster Lit, the Web page "Ebola Outbreak 2014: Information Resources," and the Virus Variation database of sequences for Ebolavirus. In cooperation with participating publishers, NLM offers free access to full-text articles from over 650 biomedical journals and 4000 online reference books through the Emergency Access Initiative. At the start of a prolonged disaster event or disease outbreak, the documents and information of most immediate use may not be in the peer-reviewed biomedical journal literature. To maintain current awareness may require using any of the following: news outlets; social media; preliminary online data, maps, and situation reports; and documents published by nongovernmental organizations, international associations, and government agencies. Similar to the pattern of interest shown in the news and social media, use of NLM Ebola-related resources is also increasing since the start of the outbreak was first reported in March 2014.

New drug information resources for pharmacists at the National Library of Medicine.

OBJECTIVE: To provide an overview of selected drug information-related databases of the National Library of Medicine (NLM), with a focus on newer resources that support the professional information needs of pharmacists and other health care providers. SUMMARY: NLM, which is the world's largest medical library, provides an array of bibliographic, factual, and evidence-based drug, herbal remedy, and dietary supplement information resources. Five of the more recently introduced online resources include areas of particular importance to pharmacists, including a repository of current product labeling/package inserts, with automated search links to associated information resources; a portal to drug information that allows pharmacists to search multiple databases simultaneously and link to related medication and health care information resources; authoritative information on the effects of medications, herbal remedies, and dietary supplements in nursing infants and their mothers; comprehensive information, including a case registry, on the potential for liver toxicity due to drugs, herbal remedies, and dietary supplements; and a pill identification system with two intuitive search methodologies. CONCLUSION: NLM provides several clinical-scientific drug information resources that are particularly useful in meeting the professional information needs of pharmacists.

National Library of Medicine Disaster Information Management Research Center: Achieving the vision, 2010-2013.

From 2010 to 2013, the National Library of Medicine (NLM) Disaster Information Management Research Center (DIMRC) continued to build its programs and services on the foundation laid in its starting years, 2008-2010. Prior to 2008, NLM had a long history of providing health information, training, and tools in response to disasters. Aware of this legacy, the NLM long range plan (Charting a Course for the 21st Century: NLM's Long Range Plan 2006-2016) called for creation of a center to show "a strong commitment to disaster remediation and to provide a platform for demonstrating how libraries and librarians can be part of the solution to this national problem". NLM is continuing efforts to ensure that medical libraries have plans for the continuity of their operations, librarians are trained to understand their roles in preparedness and response, online disaster health information resources are available for many audiences and in multiple formats, and research is conducted on tools to enhance the exchange of critical information during and following disasters. This paper describes the 2010-2013 goals and activities of DIMRC and its future plans.

On estimating probability of presence from use-availability or presence-background data.

A fundamental ecological modeling task is to estimate the probability that a species is present in (or uses) a site, conditional on environmental variables. For many species, available data consist of "presence" data (locations where the species [or evidence of it] has been observed), together with "background" data, a random sample of available environmental conditions. Recently published papers disagree on whether probability of presence is identifiable from such presence-background data alone. This paper aims to resolve the disagreement, demonstrating that additional information is required. We defined seven simulated species representing various simple shapes of response to environmental variables (constant, linear, convex, unimodal, S-shaped) and ran five logistic model-fitting methods using 1000 presence samples and 10 000 background samples; the simulations were repeated 100 times. The experiment revealed a stark contrast between two groups of methods: those based on a strong assumption that species' true probability of presence exactly matches a given parametric form had highly variable predictions and much larger RMS error than methods that take population prevalence (the fraction of sites in which the species is present) as an additional parameter. For six species, the former group grossly under- or overestimated probability of presence. The cause was not model structure or choice of link function, because all methods were logistic with linear and, where necessary, quadratic terms. Rather, the experiment demonstrates that an estimate of prevalence is not just helpful, but is necessary (except in special cases) for identifying probability of presence. We therefore advise against use of methods that rely on the strong assumption, due to Lele and Keim (recently advocated by Royle et al.) and Lancaster and Imbens. The methods are fragile, and their strong assumption is unlikely to be true in practice. We emphasize, however, that we are not arguing against standard statistical methods such as logistic regression, generalized linear models, and so forth, none of which requires the strong assumption. If probability of presence is required for a given application, there is no panacea for lack of data. Presence-background data must be augmented with an additional datum, e.g., species' prevalence, to reliably estimate absolute (rather than relative) probability of presence.

The National Library of Medicine's Disaster Information Management Research Center.

The Disaster Information Management Research Center (DIMRC) develops and provides access to health information resources and technology for disaster preparedness, response, and recovery. DIMRC focuses on maintaining access to health information at all phases of disasters, developing innovative products and services for emergency personnel, conducting research to support disaster health information management, and collaborating with other agencies and communities. Several tools are available to help emergency responders in hazardous materials or chemical, biological, radiological, or nuclear incidents. Access to the literature is made available through PubMed and the Resource Guide for Disaster Medicine and Public Health, with links to online documents and resources from numerous organizations and government agencies. In addition, DIMRC supports the Disaster Information Specialist Program, a collaborative effort to explore and promote the role of librarians and information specialists in the provision of disaster-related information resources to the workforce and communities.

National Library of Medicine Disaster Information Management Research Center: Establishment and growth, 2008-2010.

In 2008, the National Library of Medicine (NLM) established the Disaster Information Management Research Center (DIMRC). Prior to 2008, NLM had a long history of involvement in providing health information for disaster management. Aware of this legacy and moved by the catastrophic aftermath of Hurricane Katrina, the NLM long range plan (Charting a Course for the 21st Century: NLM's Long Range Plan 2006-2016) called for creation of a center to show "a strong commitment to disaster remediation and to provide a platform for demonstrating how libraries and librarians can be part of the solution to this national problem". NLM was urged to "ensure continuous access to health information and effective use of libraries and librarians when disasters occur". In response to this charge, NLM has undertaken substantial efforts to ensure that medical libraries have plans for the continuity of their operations, librarians are trained to understand their roles in preparedness and response, online disaster health information resources are available for many audiences and in multiple formats, and research is conducted on tools to enhance the exchange of critical information during and following disasters. This paper documents the history, goals, initiatives, accomplishments and future plans of the Center.

Circular smooth muscle contributes to esophageal shortening during peristalsis.

AIM: To study the angle between the circular smooth muscle (CSM) and longitudinal smooth muscle (LSM) fibers in the distal esophagus. METHODS: In order to identify possible mechanisms for greater shortening in the distal compared to proximal esophagus during peristalsis, the angles between the LSM and CSM layers were measured in 9 cadavers. The outer longitudinal layer of the muscularis propria was exposed after stripping the outer serosa. The inner circular layer of the muscularis propria was then revealed after dissection of the esophageal mucosa and the underlying muscularis mucosa. Photographs of each specimen were taken with half of the open esophagus folded back showing both the outer longitudinal and inner circular muscle layers. Angles were measured every one cm for 10 cm proximal to the squamocolumnar junction (SCJ) by two independent investigators. Two human esophagi were obtained from organ transplant donors and the angles between the circular and longitudinal smooth muscle layers were measured using micro-computed tomography (micro CT) and Image J software. RESULTS: All data are presented as mean ± SE. The CSM to LSM angle at the SCJ and 1 cm proximal to SCJ on the autopsy specimens was 69.3 ± 4.62 degrees vs 74.9 ± 3.09 degrees, P = 0.32. The CSM to LSM angle at SCJ were statistically significantly lower than at 2, 3, 4 and 5 cm proximal to the SCJ, 69.3 ± 4.62 degrees vs 82.58 ± 1.34 degrees, 84.04 ± 1.64 degrees, 84.87 ± 1.04 degrees and 83.72 ± 1.42 degrees, P = 0.013, P = 0.008, P = 0.004, P = 0.009 respectively. The CSM to LSM angle at SCJ was also statistically significantly lower than the angles at 6, 7 and 8 cm proximal to the SCJ, 69.3 ± 4.62 degrees vs 80.18 ± 2.09 degrees, 81.81 ± 1.75 degrees and 80.96 ± 2.04 degrees, P = 0.05, P = 0.02, P = 0.03 respectively. The CSM to LSM angle at 1 cm proximal to SCJ was statistically significantly lower than at 3, 4 and 5 cm proximal to the SCJ, 74.94 ± 3.09 degrees vs 84.04 ± 1.64 degrees, 84.87 ± 1.04 degrees and 83.72 ± 1.42 degrees, P = 0.019, P = 0.008, P = 0.02 respectively. At 10 cm above SCJ the angle was 80.06 ± 2.13 degrees which is close to being perpendicular but less than 90 degrees. The CSM to LSM angles measured on virtual dissection of the esophagus and the stomach on micro CT at the SCJ and 1 cm proximal to the SCJ were 48.39 ± 0.72 degrees and 50.81 ± 1.59 degrees. Rather than the angle of the CSM and LSM being perpendicular in the esophagus we found an acute angulation between these two muscle groups throughout the lower 10 cm of the esophagus. CONCLUSION: The oblique angulation of the CSM may contribute to the significantly greater shortening of distal esophagus when compared to the mid and proximal esophagus during peristalsis.

POC plots: calibrating species distribution models with presence-only data.

Statistical models are widely used for predicting species' geographic distributions and for analyzing species' responses to climatic and other predictor variables. Their predictive performance can be characterized in two complementary ways: discrimination, the ability to distinguish between occupied and unoccupied sites, and calibration, the extent to which a model correctly predicts conditional probability of presence. The most common measures of model performance, such as the area under the receiver operating characteristic curve (AUC), measure only discrimination. In contrast, we introduce a new tool for measuring model calibration: the presence-only calibration plot, or POC plot. This tool relies on presence-only evaluation data, which are more widely available than presence-absence evaluation data, to determine whether predictions are proportional to conditional probability of presence. We generalize the predicted/expected curves of Hirzel et al. to produce a presence-only analogue of traditional (presence-absence) calibration curves. POC plots facilitate visual exploration of model calibration, and can be used to recalibrate badly calibrated models. We demonstrate their use by recalibrating models made by the DOMAIN modeling method on a comprehensive set of 226 species from six regions of the world, significantly improving DOMAIN's predictive performance.