Arctic Soil Governs Whether Climate Change Drives Global Losses or Gains in Soil Carbon

Key uncertainties in terrestrial carbon cycle projections revolve around the timing, direction, and magnitude of the carbon cycle feedback to climate change. This is especially true in carbon-rich Arctic ecosystems, where permafrost soils contain roughly one third of the world's soil carbon stocks, which are likely vulnerable to loss. Using an ensemble of soil biogeochemical models that reflect recent changes in the conceptual understanding of factors responsible for soil carbon persistence, we quantify potential soil carbon responses under two representative climate change scenarios. Our results illustrate that models disagree on the sign and magnitude of global soil changes through 2100, with disagreements primarily driven by divergent responses of Arctic systems. These results largely reflect different assumptions about the nature of soil carbon persistence and vulnerabilities, underscoring the challenges associated with setting allowable greenhouse gas emission targets that will limit global warming to 1.5°C

Basal paravian functional anatomy illuminated by high-detail body outline

Body shape is a fundamental expression of organismal biology, but its quantitative reconstruction in fossil vertebrates is rare. Due to the absence of fossilized soft tissue evidence, the functional consequences of basal paravian body shape and its implications for the origins of avians and flight are not yet fully understood. Here we reconstruct the quantitative body outline of a fossil paravian Anchiornis based on high-definition images of soft tissues revealed by laser-stimulated fluorescence. This body outline confirms patagia-bearing arms, drumstick-shaped legs and a slender tail, features that were probably widespread among paravians. Finely preserved details also reveal similarities in propatagial and footpad form between basal paravians and modern birds, extending their record to the Late Jurassic. The body outline and soft tissue details suggest significant functional decoupling between the legs and tail in at least some basal paravians. The number of seemingly modern propatagial traits hint that feathering was a significant factor in how basal paravians utilized arm, leg and tail function for aerodynamic benefit.published_or_final_versio

Going in Blind: A Common Scenario in an Uncommon Situation

Audience: Medical students, interns, junior resident physicians, senior resident physiciansBackground: Power outages have been increasing in frequency in the past few years, therefore becoming an increased threat to healthcare delivery.1 While most studies related to the effects of power outages are focused on outpatient care, such as acute exacerbations of chronic lung conditions and the lack of chargeable equipment, with the increasing number of power outages, hospitals must be prepared for this situation as well.2,3 Although agencies such as the Federal Emergency Management Agency (FEMA) and the US Department of Health and Human Services (HHS) have provided guidelines for the response of hospitals to temporary loss of power,12,13 hospitals generally rely on institutional policies in response to the event of a power outage. Given the relative rarity but increasing frequency of power outages in hospital settings, this medical simulation was created to present a common occurrence in the emergency department (eg, cardiac arrest) in an uncommon setting of a power outage. Simulation has been shown to improve learner self- efficacy, confidence, and leadership skills among resuscitation teams.4,5 The role of simulation also helps learners identify latent safety threats, in this case a power outage.6 The goal of this simulation is to improve the skills of healthcare professionals with regards to managing cardiac arrest and to encourage these practitioners to consider their own hospital guidelines in response to a power outage.Educational Objectives: By the end of this simulation, learners will be able to (1) evaluate and treat a patient experiencing myocardial infarction and subsequent cardiac arrest during a power outage, (2) describe the local protocols for managing patient care during a power outage, (3) demonstrate the ability to coordinate a medical team during a simulated power outage in an emergency department with limited resources, (4) manage a cardiac arrest patient by following Advanced Cardiac Life Support (ACLS) protocols for bradycardia and ventricular fibrillation, and (5) justify the urgency of transfer to a certified ST segment elevation myocardial infarction center/cardiac intensive care unit, referencing the recommended 120-minute door-to- balloon time.Educational Methods: This simulation was conducted with a high-fidelity mannequin. A total of six residents of various post-graduate year (PGY) levels participated in the simulated patient encounter as part of the simulation competition at the Western Regional meeting of the Society for Academic Emergency Medicine.Research Methods: This case was assessed for educational content and piloted by emergency medicine attendings from several institutions prior to running the case for the Western Regional meeting. The efficacy of the content was assessed by oral feedback.Results: The case was well-received by both the attending physicians who evaluated the case prior to running the scenario at the Western Regional meeting and the emergency medicine residents who participated in the case at the Western Regional meeting.Discussion: Overall, this simulation was well received by both the learners and the debriefers. General feedback was positive, with the perception of increased confidence among learners and reflection upon individual hospital policy in the event of a power outage

Multiple models and experiments underscore large uncertainty in soil carbon dynamics

Soils contain more carbon than plants or the atmosphere, and sensitivities of soil organic carbon (SOC) stocks to changing climate and plant productivity are a major uncertainty in global carbon cycle projections. Despite a consensus that microbial degradation and mineral stabilization processes control SOC cycling, no systematic synthesis of long-term warming and litter addition experiments has been used to test process-based microbe-mineral SOC models. We explored SOC responses to warming and increased carbon inputs using a synthesis of 147 field manipulation experiments and five SOC models with different representations of microbial and mineral processes. Model projections diverged but encompassed a similar range of variability as the experimental results. Experimental measurements were insufficient to eliminate or validate individual model outcomes. While all models projected that CO efflux would increase and SOC stocks would decline under warming, nearly one-third of experiments observed decreases in CO flux and nearly half of experiments observed increases in SOC stocks under warming. Long-term measurements of C inputs to soil and their changes under warming are needed to reconcile modeled and observed patterns. Measurements separating the responses of mineral-protected and unprotected SOC fractions in manipulation experiments are needed to address key uncertainties in microbial degradation and mineral stabilization mechanisms. Integrating models with experimental design will allow targeting of these uncertainties and help to reconcile divergence among models to produce more confident projections of SOC responses to global changes. 2

Novel Inactivation of the Causative Fungus of White Nose Syndrome with Methoxsalen and Ultraviolet A Light

White Nose Syndrome (WNS) is a newly recognized disease responsible for the rapid mass destruction of the North American bat populations. This study addressed the novel inactivation of fungal spores from Pseudogymnoascus destructans, the causative agent of WNS, using ultraviolet A (UVA) light at 365nm and methoxsalen, a photosensitizer from a family of compounds known as furanocoumarins. Penicillium crustosum, an environmental fungus, was studied as a comparator. Spore suspensions were soaked in specific concentrations of methoxsalen and subsequently exposed to UVA light. The plates were examined for both spore inactivation and resultant inhibition of colony growth. The results demonstrated that methoxsalen + UVA was an effective method for inactivating fungal spores of P. destructans and P. crustosum. The importance of this study is the potential control of WNS and other destructive environmental fungi

Accurate automated quantitative imaging of tortoise erythrocytes using the NIS image analysis system

The standard method for assessing blood cell characteristics using an ocular micrometer is time-consuming and limited. We used the Nikon NIS Elements imaging software and May-Grünwald-Giemsa staining to determine whether automated image analysis is suitable for rapid and accurate quantitative morphometry of erythrocytes. Blood was collected during four seasons from 126 geometric tortoises and the blood smears were evaluated for cell (C) and nuclear (N) characteristics of the erythrocytes. We measured area, length (L), width (W), perimeter, elongation and pixelation intensity, and calculated L/W and N/C areas. Erythrocyte size differed among cohorts; females, the larger sex, had smaller erythrocytes than either males or juveniles. Males had more elongated erythrocytes than females and erythrocytes of adults were more elongated than those of juveniles. Erythrocyte size and shape influence the efficiency of gas exchange owing to surface area to volume ratios, which are greater for small, elongated cells than for large, round cells. The high N/C ratio and low pixelation intensities of males and juveniles indicate that they may have had more immature erythrocytes in their circulation than females. The use of pixelation intensity to indicate the presence of immature erythrocytes was validated by seasonal differences that corresponded to the biology of the tortoises. Pixelation intensity was lowest in winter. We found that automated image analysis is a rapid and reliable method for determining cell size and shape, and it offers the potential for distinguishing among developmental stages that differ in staining intensity. The method should be useful for rapid health assessments, particularly of threatened species, and for comparative studies among different vertebrates.Web of Scienc

Vitamin D supplementation and breast cancer prevention : a systematic review and meta-analysis of randomized clinical trials

In recent years, the scientific evidence linking vitamin D status or supplementation to breast cancer has grown notably. To investigate the role of vitamin D supplementation on breast cancer incidence, we conducted a systematic review and meta-analysis of randomized controlled trials comparing vitamin D with placebo or no treatment. We used OVID to search MEDLINE (R), EMBASE and CENTRAL until April 2012. We screened the reference lists of included studies and used the “Related Article” feature in PubMed to identify additional articles. No language restrictions were applied. Two reviewers independently extracted data on methodological quality, participants, intervention, comparison and outcomes. Risk Ratios and 95% Confident Intervals for breast cancer were pooled using a random-effects model. Heterogeneity was assessed using the I2 test. In sensitivity analysis, we assessed the impact of vitamin D dosage and mode of administration on treatment effects. Only two randomized controlled trials fulfilled the pre-set inclusion criteria. The pooled analysis included 5372 postmenopausal women. Overall, Risk Ratios and 95% Confident Intervals were 1.11 and 0.74–1.68. We found no evidence of heterogeneity. Neither vitamin D dosage nor mode of administration significantly affected breast cancer risk. However, treatment efficacy was somewhat greater when vitamin D was administered at the highest dosage and in combination with calcium (Risk Ratio 0.58, 95% Confident Interval 0.23–1.47 and Risk Ratio 0.93, 95% Confident Interval 0.54–1.60, respectively). In conclusions, vitamin D use seems not to be associated with a reduced risk of breast cancer development in postmenopausal women. However, the available evidence is still limited and inadequate to draw firm conclusions. Study protocol code: FARM8L2B5L

Lip plumper contact urticaria.

Lip plumpers are relatively new topical agents on the market that are designed to increase lip volume minutes to days after application. In this report, we describe a case of lip plumper contact urticaria in a young boy. We also discuss the mechanisms of action of lip plumpers and the sociocultural reasons for their use

Local Difference Measures between Complex Networks for Dynamical System Model Evaluation

Acknowledgments We thank Reik V. Donner for inspiring suggestions that initialized the work presented herein. Jan H. Feldhoff is credited for providing us with the STARS simulation data and for his contributions to fruitful discussions. Comments by the anonymous reviewers are gratefully acknowledged as they led to substantial improvements of the manuscript.Peer reviewedPublisher PD