bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of peripapillary vascular flow using optical coherence tomography angiography in optic nerve head drusen
Authors: Leal‐González Mercedes , Pessanha Filipa , Azevedo González‐Oliva Martim , Pérez‐Fernández Elia , Gili Pablo
Published: May 2020

Importance

To evaluate peripapillary vascular flow using optical coherence tomography angiography (angio‐OCT) in patients with optic nerve head drusen (ONHD).

Background

Angio‐OCT allows non‐invasive visualization and quantification peripapillary vascular flow.

Design

Cross‐sectional study.

Participants

Seventy‐six eyes of 40 patients.

Methods

Between January 2018 and May 2019, consecutive patients with ONHD and healthy controls underwent a complete ocular assessment, including visual acuity testing, biomicroscopy, tonometry, funduscopy, automated perimetry, retinography and autofluorescence, spectral‐domain OCT and peripapillary angio‐OCT.

Main Outcomes Measures

Peripapillary vascular flow, vascular density, retinal nerve fibre layer (RNFL) and ganglion cell layer (GCL) thicknesses.

Results

We included 23 patients with ONHD (42 eyes, 32 with visible drusen; mean age 50.96 years, 12 men) and 17 control patients (34 eyes; mean age 47.12 years, 7 men), without significant differences in age or sex. Vascular flow and density were significantly lower in patients with ONHD (0.409% and 40.18%, respectively) than in normal eyes (0.438% and 43.30%, respectively) (P = .006 and P < .001). RNFL and GCL thicknesses were significantly lower in patients with ONHD (81.81 and 77.43 μm, respectively) than in controls (91.38 and 81.97 μm, respectively) (P = .001 and P = .032). We obtained high correlation indexes between RNFL and GCL and vascular flow and density (RNFL = 0.702 and 0.744, respectively, and GCL = 0.808 and 0.857, respectively).

Conclusions and Relevance

Angio‐OCT demonstrated significant reductions in peripapillary vascular flow and vascular density in patients with ONHD, with strong correlations with RNFL and GCL thicknesses.
Non‐Uniform Subdivision Surfaces with Sharp Features
Authors: Tian Yufeng , Li Xin , Chen Falai
Published: May 2020

Sharp features are important characteristics in surface modelling. However, it is still a significantly difficult task to create complex sharp features for Non‐Uniform Rational B‐Splines compatible subdivision surfaces. Current non‐uniform subdivision methods produce sharp features generally by setting zero knot intervals, and these sharp features may have unpleasant visual effects. In this paper, we construct a non‐uniform subdivision scheme to create complex sharp features by extending the eigen‐polyhedron technique. The new scheme allows arbitrarily specifying sharp edges in the initial mesh and generates non‐uniform cubic B‐spline curves to represent the sharp features. Experimental results demonstrate that the present method can generate visually more pleasant sharp features than other existing approaches.
From 2.5D Bas‐relief to 3D Portrait Model
Authors: Zhang Yu‐Wei , Wang Wenping , Chen Yanzhao , Liu Hui , Ji Zhongping , Zhang Caiming
Published: May 2020

In contrast to 3D model that can be freely observed, p ortrait bas‐relief projects slightly from the background and is limited by fixed viewpoint. In this paper, we propose a novel method to reconstruct the underlying 3D shape from a single 2.5D bas‐relief, providing observers wider viewing perspectives. Our target is to make the reconstructed portrait has natural depth ordering and similar appearance to the input. To achieve this, we first use a 3D template face to fit the portrait. Then, we optimize the face shape by normal transfer and Poisson surface reconstruction. The hair and body regions are finally reconstructed and combined with the 3D face. From the resulting 3D shape, one can generate new reliefs with varying poses and thickness, freeing the input one from fixed view. A number of experimental results verify the effectiveness of our method.
Pulmonary Metastasectomy in Colorectal Cancer: updated analysis of 93 randomized patients – control survival is much better than previously assumed
Authors: Milosevic M. , Edwards J. , Tsang D. , Dunning J. , Shackcloth M. , Batchelor T. , Coonar A. , Hasan J. , Davidson B. , Marchbank A. , Grumett S. , Williams N.R. , Macbeth F. , Farewell V. , Treasure T.
Published: May 2020

Aim

Lung metastases from colorectal cancer are resected in selected patients in the belief that this confers a significant survival advantage. It is generally assumed that the 5‐year survival of these patients would be near zero without metastasectomy. We tested the clinical effectiveness of this practice in Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC), a randomized, controlled noninferiority trial.

Method

Multidisciplinary teams in 14 hospitals recruited patients with resectable lung metastases into a two‐arm trial. Randomization was remote and stratified according to site, with minimization for age, sex, primary cancer stage, interval since primary resection, prior liver involvement, number of metastases and carcinoembryonic antigen level. The trial management group was blind to patient allocation until after intention‐to‐treat analysis.

Results

From 2010 to 2016, 93 participants were randomized. These patients were 35–86 years of age and had between one and six lung metastases at a median of 2.7 years after colorectal cancer resection; 29% had prior liver metastasectomy. The patient groups were well matched and the characteristics of these groups were similar to those of observational studies. The median survival after metastasectomy was 3.5 (95% CI: 3.1–6.6) years compared with 3.8 (95% CI: 3.1–4.6) years for controls. The estimated unadjusted hazard ratio for death within 5 years, comparing the metastasectomy group with the control group, was 0.93 (95% CI: 0.56–1.56). Use of chemotherapy or local ablation was infrequent and similar in each group.

Conclusion

Patients in the control group (who did not undergo lung metastasectomy) have better survival than is assumed. Survival in the metastasectomy group is comparable with the many single‐arm follow‐up studies. The groups were well matched with features similar to those reported in case series.
Evaluating the relationships between the legal and illegal international wildlife trades
Authors: Tittensor Derek P. , Harfoot Michael , McLardy Claire , Britten Gregory L. , Kecse‐Nagy Katalin , Landry Bryan , Outhwaite Willow , Price Becky , Sinovas Pablo , Blanc Julian , Burgess Neil D. , Malsch Kelly
Published: May 2020

The international legal trade in wildlife can provide economic and other benefits, but when unsustainable can be a driver of population declines. This impact is magnified by the additional burden of illegal trade, yet how it covaries with legal trade remains little explored. We combined law‐enforcement time‐series of seizures of wildlife goods imported into the United States (US) and the European Union (EU) with data on reported legal trade to evaluate the evidence for any relationships. Our analysis examined 28 US and 20 EU products derived from CITES‐listed species with high volume and frequency of both reported trade and seizures. On average, seizures added 28% and 9% to US and EU reported legal trade levels respectively, and in several cases exceeded legal imports. We detected a significant but weak overall positive relationship between seizure volumes and reported trade into the US over time, but not into the EU. These results highlight the importance of maintaining long‐term records of border seizures and enforcement effort, and accounting for illegal trade where possible in non‐detriment findings. Our findings suggest a complex and nuanced temporal association between the illegal and legal wildlife trades.
Outcomes of patients with cardiac cirrhosis undergoing heart transplantation
Authors: Ngu Natalie L. Y. , Majeed Ammar , Roberts Stuart K. , Bergin Peter , Kemp William
Published: May 2020

Introduction

Cardiac cirrhosis is common in patients with advanced heart failure and can limit heart transplant eligibility. We examined the outcomes of patients with cardiac cirrhosis following orthotopic heart transplantation.

Material and methods

A retrospective matched cohort study of adult patients with cirrhosis undergoing heart transplantation at an Australian hospital from 2009 to 2017 was performed. Cirrhosis was established by either (a) histopathology or (b) combination of radiological features of cirrhosis and portal hypertension plus clinical features of portal hypertension. Primary objectives were to assess mortality, perioperative, and long‐term complications. Matching was performed with non‐cirrhotic patients undergoing heart transplantation in a 4:1 ratio.

Results

Five patients with biopsy‐proven cirrhosis or portal hypertension and 20 matched controls without cirrhosis were included. Additionally, 5 patients with clinical and radiological evidence of cirrhosis were assessed separately. The groups were well‐matched for age at transplant, year of transplant, gender, and comorbidities. Mortality was more frequent but not significantly greater in the cirrhosis group with 2 deaths within 4 months of transplant compared to 1 death each in the no cirrhosis and suspected cirrhosis groups (40%, 5%, 20% P = .40). The median duration of intensive care unit stay was longer in the cirrhosis group compared to the suspected cirrhosis group (8 vs 6 days, P = .03); however, there was no difference in total hospitalization (P = .56) or in median duration of admission (0.64) compared to the no cirrhosis group.

Conclusions

These findings suggest that there is greater mortality associated with cases of definite cirrhosis compared to suspected or matched controls following orthotopic heart transplantation; however, statistical significance was not reached. Admission length and complication rates were similar compared to those without cirrhosis. Future studies are warranted to further evaluate mortality risk in a larger population.
A Place at the Well: The Imperative for Farmer Inclusion in Water Conservation Policy Design
Authors: O’Connell Caela , Billingsley Krista
Published: May 2020

Achieving cleaner water for rural and suburban communities in a sustainable way requires approaches tailored to the unique socioeconomic, ecological, and historic contexts embedded in a particular community and place. Water quality trading (WQT) is a payment for ecosystem services style policy that is currently popular across North America as a mechanism to reduce water pollution from rural communities. Yet this approach is failing to generate markets with enough trades to measurably improve waterways. Some failures are attributed to poor program design and others to stakeholder communities who are averse to the premise or morality of WQT. However, rural communities are not homogenous and many are in fact amenable to payment for ecosystem services policies such as WQT. Although our case study identified Tennessee watersheds as “feasible” locations, we present evidence that the typical program design parameters would fail, despite having a willing population of farmers. We argue that identifying amenable communities or feasible locations simplifies the agency of stakeholders and is ultimately insufficient to make ecosystem services programs work unless the design and implementation phases of the programs include local stakeholders.
Superficial dermal melanocytosis of the elderly: An exceptional occurrence?
Authors: Saggini Andrea , Dill Dorothee , Kleimann Pia , Kutzner Heinz
Published: May 2020

The development of flat pigmented lesions on chronically sun‐damaged (CSD) skin of the face may represent the clinical manifestation of a wide variety of hyperplastic/neoplastic melanocytic proliferations. We report the exceptional case of an acquired pigmented patch occurring on CSD skin, histopathologically characterized by diffuse hyperplasia of dendritic/spindled melanocytes in the superficial dermis within a widened band of actinic elastosis. This lesion was associated with a small focus of early invasive lentigo maligna melanoma (LMM). We show the melanocytic nature of the population of dermal pigmented cells by means of single and double immunohistochemical staining for melanocytic and histiocytic markers. The biologic significance of the focus of LMM within the hyperpigmented lesion (whether random collision phenomenon or causally related occurrence), as well as the pathogenesis of the whole dermal lesion are difficult to elucidate. Our case emphasizes the need for a better understanding of the pathophysiology of so‐called dermal melanocytes.
Effect of pain on mood affective disorders in adults with cerebral palsy
Authors: Whitney Daniel G , Bell Sarah , Whibley Daniel , Van der Slot Wilma M A , Hurvitz Edward A , Haapala Heidi J , Peterson Mark D , Warschausky Seth A
Published: May 2020

Aim

To determine if pain is associated with 12‐month incidence of mood affective disorders (MAD) in adults with cerebral palsy (CP).

Method

Data from Optum Clinformatics® Data Mart (2013–2016) were used for this retrospective cohort study. Diagnostic codes were used to identify adults (≥18y) with CP, incident cases of MAD, and covariates (other neurodevelopmental conditions, sleep disorders, arthritis). Pain (any type, location) was identified between 1st October 2014 and 30th September 2015. The pain group was divided into new or consistent pain if they had a history of pain (i.e. consistent) in the 12 months before their first pain claim date. Crude incidence rates of MAD (expressed per 100 person‐years) were estimated. Cox regression was used to estimate hazard ratio (95% confidence interval [CI]) of MAD after adjusting for covariates.

Results

Adults that had new pain (n=859; incidence rate=15.5) or consistent pain (n=1303; incidence rate=17.9) had greater crude incidence rate of MAD compared to adults without pain (n=3726; incidence rate=5.9). The elevated rate of MAD remained after adjusting for covariates, for new pain (hazard ratio=2.4; 95% CI=1.9–3.0) and consistent pain (hazard ratio=2.1; 95% CI=1.7–2.7).

Interpretation

Pain is associated with greater incidence of MAD in adults with CP. This association remained after accounting for potential confounding factors.

What this paper adds

Pain was associated with higher 12‐month incidence of mood affective disorders (MAD).

The 12‐month MAD incidence was similar between new and consistent pain groups.

The MAD incidence remained higher adjusting for neurodevelopmental comorbidities, sleep disorders, and arthritis.
Direct measurement of cardiac stiffness using echocardiographic shearwave imaging during open‐chest surgery: A pilot study in human
Authors: Saloux Eric , Gauthier Michael , Buklas Dimitrios , Saplacan Vladimir , Denoyer Antoine , Labombarda Fabien , Raitiere Olivier , Criton Aline , Milliez Paul , Bauer Fabrice
Published: May 2020

Purpose

Cardiac stiffness is a marker of diastolic function with a strong prognostic significance in many heart diseases that is not measurable in clinical practice. This study investigates whether elastometry, a surrogate for organ stiffness, is measurable in the heart using ShearWave Imaging.

Methods

In 33 anesthetized patients scheduled for cardiac surgery, ShearWave imaging was acquired epicardially using a dedicated ultrasound machine on the left ventricle parallel to the left anterior descending coronary artery in a loaded heart following the last cardiac beat. Cardiac elastometry was measured offline using the Young modulus with customized software.

Results

Overall, the ejection fraction was 61 ± 10%. E/A and E/e′ ratios were 1.0 ± 0.5 and 10.5 ± 4.1, respectively. Cardiac elastometry averaged 15.3 ± 5.3 kPa with a median of 18 kPa. Patients with high elastometry >18 kPa were older (P = .04), had thicker (P = .02) but smaller LV (P = .004), had larger left atria (P = .05) and a higher BNP level (P = .04). We distinguished three different transmural elastometry patterns: higher epicardial, higher endocardial, or uniformly distributed elastometry.

Conclusion

Elastometry measurement was feasible for the human heart. This surrogate for cardiac stiffness dichotomized patients with low and high elastometry, and provided three different phenotypes of transmural elastometry with link to diastolic function.
Geographical differences in habitat relationships of cetaceans across an ocean basin
Authors: Mannocci Laura , Roberts Jason J. , Pedersen Eric J. , Halpin Patrick N.
Published: May 2020

The distributions of highly mobile marine species such as cetaceans are increasingly modeled at basin scale by combining data from multiple regions. However, these basin‐wide models often overlook geographical variations in species habitat relationships between regions. We tested for geographical variations in habitat relationships for a suite of cetacean taxa between the two sides of the North Atlantic basin. Using cetacean visual survey data and remote sensing data from the western and eastern basin in summer, we related the probability of presence of twelve cetacean taxa from three guilds to seafloor depth, sea surface temperature and primary productivity. In a generalized additive model framework, we fitted 1) basin‐wide (BW) models, assuming a single global relationship, 2) region‐specific intercepts (RI) models, assuming relationships with the same shape in both regions, but allowing a region‐specific intercept and 3) region‐specific shape (RS) models, assuming relationships with different shapes between regions. RS models mostly yielded significantly better fits than BW models, indicating cetacean occurrences were better modeled with region‐specific than with global relationships. The better fits of RS models over RI models further provided statistical evidence for differences in the shapes of region‐specific relationships. Baleen whales showed striking differences in both the shapes of relationships and their mean presence probabilities between regions. Deep diving whales and delphinoids showed contrasting relationships between regions with few exceptions (e.g. non‐statistically different shapes of region‐specific relationships for harbor porpoise and beaked whales with depth). Our findings stress the need to account for geographical differences in habitat relationships between regions when modeling species distributions from combined data at the basin scale. Our proposed hypotheses offer a roadmap for understanding why habitat relationships may geographically vary in cetaceans and other highly mobile marine species.
Effects of nonnative species on the stability of riverine fish communities
Authors: Erős Tibor , Comte Lise , Filipe Ana Filipa , Ruhi Albert , Tedesco Pablo A. , Brose Ulrich , Fortin Marie‐Josée , Giam Xingli , Irving Katie , Jacquet Claire , Larsen Stefano , Sharma Sapna , Olden Julian D.
Published: May 2020

Despite the increasing ubiquity of biological invasions worldwide, little is known about the scale‐dependent effects of nonnative species on real‐world ecological dynamics. Here, using an extensive time series dataset of riverine fish communities across different biogeographic regions of the world, we assessed the effects of nonnative species on the temporal variability and synchrony in abundance at different organizational levels (population, metapopulation, community and metacommunity) and spatial scales (stream reach and river basin). At the reach scale, we found that populations of nonnative species were more variable over time than native species, and that this effect scaled up to the community level – significantly destabilizing the dynamics of riverine fish communities. Nonnative species not only contributed to reduced community stability, but also increased variability of native populations. By contrast, we found no effect of nonnative species dominance on local interspecific synchrony among native species. At the basin scale, nonnative metapopulations were again more variable than the native ones. However, neither native metapopulations nor metacommunities showed differences in temporal variability or synchrony as nonnative species dominance increased basin‐wide. This suggests a ‘dilution effect’ where the contribution to regional stability of local native populations from sites displaying low levels of invasion reduced the destabilizing effects of nonnative species. Overall, our results indicate that accounting for the destabilizing effect of nonnative species is critical to understanding native species persistence and community stability.
Disparate dispersal limitation inGeomalacusslugs unveiled by the shape and slope of the genetic–spatial distance relationship
Authors: Gómez‐Rodríguez Carola , Miller Kirsten E. , Castillejo José , Iglesias‐Piñeiro Javier , Baselga Andrés
Published: May 2020

Long‐term dispersal ability is a key species’ trait constraining species ranges and thus large‐scale biodiversity patterns. Here we infer the long‐term dispersal abilities of threeGeomalacus(Gastropoda, Pulmonata) species from their range‐wide genetic–spatial distance relationships. This approach follows recent advances in statistical modelling of the analogous pattern at the community level: the distance decay in assemblage similarity. While linear relationships are expected for species with high long‐term dispersal abilities, asymptotic relationships are expected for those with more restricted mobility. We evaluated three functional forms (linear, negative exponential and power‐law) for the relationship between genetic distance (computed from mitochondrialcox1sequences, n = 701) and spatial distance. Range fragmentation at present time and at the Last Glacial Maximum was also estimated based on the projection of climatic niches. The power‐law function best fit the relationship between genetic and spatial distances, suggesting strong dispersal limitation and long‐term population isolation in all three species. However, the differences in slope and explained variance pointed to disparities in dispersal ability among these weak dispersers. Phylogeographic patterns ofGeomalacusspecies are thus largely driven by the same major process (i.e. dispersal limitation), operating at different strengths. This strong dispersal limitation results in geographic clustering of genetic diversity that makes these species highly vulnerable to genetic erosion due to climate change.
Bacteria associated with Lucilia sericata larvae reared on fish wastes
Authors: Ulanova Ruzalia V. , Tikhonova Ekaterina N. , Kravchenko Irina K.
Published: May 2020

The green blowfly, Lucilia sericata (Meigen) (Diptera: Calliphoridae), is a cosmopolitan species of great medical, veterinary, and forensic importance. In addition, their larvae are among the most promising agents for the bioconversion of low‐quality biomass, such as organic waste, into sustainable and nutritionally valuable proteins for farmed fish and poultry. Despite the considerable medical and economic importance, the current literature provides limited information about microbiota associated with larvae. The present study aims to fill this knowledge gap. Freshly harvested L. sericata larvae (maggots) grown on fish wastes were investigated by conventional and molecular approaches to evaluate culturable microbial numbers and unculturable microbial diversity associated with the larval cuticle (external samples) and the internal body. In total 200 bacterial isolates were obtained; 46% of the strains originated from external samples and 58% originated from internal body samples produced extracellular protease enzymes, which may be involved in the digestion of proteins during larval feeding. In total 12 predominant bacteria with high proteolytic activity were further identified by morphological, physiological, biochemical, and molecular tools. Proteolytic bacteria in internal samples included Proteus, Providencia, Micrococcus, Deinococcus, whereas in external samples Providencia, Pseudomonas, and Acinetobacter were found. 16S rRNA clone library analysis revealed that the majority of internal bacteria (35%) were taxonomically assigned as Xanthomonadaceae (Schineria, Xylella, Ignnatzchineria), 28% Morganellaceae (Proteus, Providencia, Serratia), and 14% Enterobacteriaceae (Vagococcus, Serratia). Less abundant were bacteria of the genera Clostridium (3%), Erypelothrix (3%), and Oceanispherum (2%). This knowledge will be useful for biotechnological application of L. sericata.
Relationships between spectral features, iron oxides and colours of surface soils in northern Jordan
Authors: Sahwan Wahib , Lucke Bernhard , Sprafke Tobias , Vanselow Kim A. , Bäumler Rupert
Published: May 2020

Ground data on spectral characteristics of Jordan's soils remain sparse, which makes the interpretation of remote sensing datasets challenging. These are, however, very useful for predicting soil properties and agricultural suitability. Previous studies have shown that soil colours correlate well with degrees of weathering intensity, as indicated by magnetic parameters and dithionite‐extractable iron (Fed) contents along a climosequence in northern Jordan. This study enlarges the database by the results of 160 bulk samples that were collected systematically from the soil surface at 40 locations. In addition to soil colour and contents of Fed, we explore mean soil reflectance spectra (MSRS) measured by analytical spectral devices (ASD) and analyse the morphological conditions of the spectra referring to the effects of iron oxides on spectral behaviours. Results show a high correlation of spectral behaviours and colour variations with Fe oxides, and no correlation with soil organic carbon Corg. The influence of the Fe oxide contents is clearly apparent in the visible range (VIS). The presence of CaCO3 increases the reflectance in all spectral ranges. Six soil groups (Gr. I ‐ Gr. VI) were discerned qualitatively and quantitatively in the study area, which largely mirror the intensity of red colour expressed by redness indices.

Highlights

In northwestern Jordan there is an evident connection between the spectral properties, chemistry and soil colour.

This study established a preliminary spectral library of soils in NW Jordan to facilitate the use of remote sensing in soil studies.

The morphological properties and statistical analysis of the spectral data show that spectra of soils in NW Jordan are dominated by iron oxides.

Spectral properties can be used to characterize the soil colours and types of Fe oxides in soils of Jordan.
Open approach to correct traumatic closed tracheal lacerations: A case series
Authors: Iglesias‐García M. , Lepage O. M. , Ezquerra Calvo L. J. , Muñoz Morán J. A.
Published: May 2020

Reports of tracheal injuries in horses are rare compared with those in small animals and humans. Although uncommon, tracheal injuries can be life threatening if they progress or are not treated. Different treatments have been described depending on the severity of the problem. This report describes the successful surgical treatment of three cases of closed tracheal lacerations through an intraluminal surgical approach.
Mu opioid receptors in the medial preoptic area govern social play behavior in adolescent male rats
Authors: Zhao Changjiu , Chang Liza , Auger Anthony P. , Gammie Stephen C. , Riters Lauren V.
Published: May 2020

Neural systems underlying important behaviors are usually highly conserved across species. The medial preoptic area (MPOA) has been demonstrated to play a crucial role in reward associated with affiliative, nonsexual, social communication in songbirds. However, the role of MPOA in affiliative, rewarding social behaviors (eg, social play behavior) in mammals remains largely unknown. Here we applied our insights from songbirds to rats to determine whether opioids in the MPOA govern social play behavior in rats. Using an immediate early gene (ie, Egr1, early growth response 1) expression approach, we identified increased numbers of Egr1‐labeled cells in the MPOA after social play in adolescent male rats. We also demonstrated that cells expressing mu opioid receptors (MORs, gene name Oprm1) in the MPOA displayed increased Egr1 expression when adolescent rats were engaged in social play using double immunofluorescence labeling of MOR and Egr1. Furthermore, using short hairpin RNA‐mediated gene silencing we revealed that knockdown of Oprm1 in the MPOA reduced the number of total play bouts and the frequency of pouncing. Last, RNA sequencing differential gene expression analysis identified genes involved in neuronal signaling with altered expression after Oprm1 knockdown, and identified Egr1 as potentially a key modulator for Oprm1 in the regulation of social play behavior. Altogether, these results show that the MPOA is involved in social play behavior in adolescent male rats and support the hypothesis that the MPOA is part of a conserved neural circuit across vertebrates in which opioids act to govern affiliative, intrinsically rewarded social behaviors.
Low‐severity fire as a mechanism of organic matter protection in global peatlands: Thermal alteration slows decomposition
Authors: Flanagan Neal E. , Wang Hongjun , Winton Scott , Richardson Curtis J.
Published: May 2020

Worldwide, regularly recurring wildfires shape many peatland ecosystems to the extent that fire‐adapted species often dominate plant communities, suggesting that wildfire is an integral part of peatland ecology rather than an anomaly. The most destructive blazes are smoldering fires that are usually initiated in periods of drought and can combust entire peatland carbon stores. However, peatland wildfires more typically occur as low‐severity surface burns that arise in the dormant season when vegetation is desiccated, and soil moisture is high. In such low‐severity fires, surface layers experience flash heating, but there is little loss of underlying peat to combustion. This study examines the potential importance of such processes in several peatlands that span a gradient from hemiboreal to tropical ecozones and experience a wide range of fire return intervals. We show that low‐severity fires can increase the pool of stable soil carbon by thermally altering the chemistry of soil organic matter (SOM), thereby reducing rates of microbial respiration. Using X‐ray photoelectron spectroscopy and Fourier transform infrared, we demonstrate that low‐severity fires significantly increase the degree of carbon condensation and aromatization of SOM functional groups, particularly on the surface of peat aggregates. Laboratory incubations show lower CO2emissions from peat subjected to low‐severity fire and predict lower cumulative CO2emissions from burned peat after 1–3 years. Also, low‐severity fires reduce the temperature sensitivity (Q10) of peat, indicating that these fires can inhibit microbial access to SOM. The increased stability of thermally altered SOM may allow a greater proportion of organic matter to survive vertical migration into saturated and anaerobic zones of peatlands where environmental conditions physiochemically protect carbon stores from decomposition for thousands of years. Thus, across latitudes, low‐severity fire is an overlooked factor influencing carbon cycling in peatlands, which is relevant to global carbon budgets as climate change alters fire regimes worldwide.
Growth and resilience responses of Scots pine to extreme droughts across Europe depend on predrought growth conditions
Authors: Bose Arun K. , Gessler Arthur , Bolte Andreas , Bottero Alessandra , Buras Allan , Cailleret Maxime , Camarero J. Julio , Haeni Matthias , Hereş Ana‐Maria , Hevia Andrea , Lévesque Mathieu , Linares Juan C. , Martinez‐Vilalta Jordi , Matías Luis , Menzel Annette , Sánchez‐Salguero Raúl , Saurer Matthias , Vennetier Michel , Ziche Daniel , Rigling Andreas
Published: May 2020

Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees’ phenotypic variability, which is, in turn, affected by long‐term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree‐level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree‐, site‐, and drought‐related factors and their interactions driving the tree‐level resilience to extreme droughts. We used a tree‐ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid‐elevation and low productivity sites from 1980–1999 to 2000–2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree‐level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long‐term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation.
COVID‐19 and raising the value of care
Authors: Thomason Bobbi , Macias‐Alonso Inmaculada
Published: May 2020

In this opinion piece, we argue the current pandemic is shining a light on caregiving as critical work that is under‐valued and under‐paid. We call upon national lawmakers to raise the value of care work. Doing so would also make progress in solving another national crisis: closing the gender wage gap. We explore how the gender wage gap is driven primarily by the fact that men and women sort into different work, with women being over‐represented in work where they care for others and in work that allows them to care for their families.
Using Wavelet Coherence to Characterize Surface Water Infiltration into a Low‐Lying Karst Aquifer
Authors: Schuler Philip , Cantoni Èlia , Duran Léa , Johnston Paul , Gill Laurence
Published: May 2020

Karstified carbonate aquifers may receive significant recharge contributions from losing streams, hence, the knowledge about surface water‐groundwater (SW‐GW) interactions is crucial with regard to water management (e.g., source protection zone delineation). The dynamics of SW‐GW interactions may depend on factors such as the relative water levels between streams and aquifers, resulting in a temporal variation of exchange, which imposes complexity to the understanding of such dynamics. This study highlights the use of high‐resolution time series and multiresolution analysis to help to gain insights into such complex dynamics. Wavelet coherence is applied on hourly time series of rainfall, stream, and spring discharges of a low‐lying karstified spring catchment to yield a correlation in the time‐frequency domain. This analysis provides comprehensive information on the overall impact of the river on the spring, which is supported by the cross‐correlation function, as well as by more detailed information, including time‐variant influences such as a threshold level of influence. Field observations of turbidity sampling at the spring appear to support this interpretation. This innovative approach relies on basic hydrological parameters, water level, or discharge, and is therefore applicable to many other systems with such existing time series.
Are Visible Fractures Accurate Predictors of Flow and Mass Transport in Fractured Till?
Authors: Young Nathan L. , Simpkins William W. , Horton Robert
Published: May 2020

Tracer experiments conducted in the laboratory on undisturbed core samples (<7.3‐cm‐diameter) have been a standard method for estimating hydraulic and transport properties of fractured till since the 1980s. This study assesses the relationship between visible fractures on the top and bottom of core samples and the resulting hydraulic and mass transport properties of the core. We hypothesized that more visible fractures would indicate the presence of a well‐connected fracture network, leading to greater hydraulic conductivity (K) values and earlier chemical breakthrough times. To test this hypothesis, water flow and bromide (Br‐) tracer experiments were performed on 10, 16‐cm diameter, 16‐cm‐tall samples of fractured Dows Formation till from central Iowa. Visually identifiable fractures were present on the top and bottom of every sample. Results indicate that the visual identification of fractures does not predict a connected fracture network, as some samples produced breakthrough curves showing rapid first arrival times and shapes characteristic of solute transport in a fractured medium, while others appeared similar to an unfractured medium. No correlation was found between the number of visible fractures and K (Pearson's r = 0.25), or Br‐ first arrival time (r = −0.33), but a strong negative correlation between K and first arrival time (r = −0.92). Results indicate that the sample volume was not large enough to reliably contain a connected fracture network. Thus, testing large volumes of till at the field scale coupled with fracture‐flow modeling likely represents the best approach for estimating hydraulic and mass transport properties for fractured till.
The increasing prevalence and adverse impact of morbid obesity in paediatric acute pancreatitis
Authors: Thavamani Aravind , Umapathi Krishna K. , Roy Aparna , Krishna Somashekar G.
Published: May 2020

Objective

Morbid obesity is proinflammatory has been associated with adverse clinical outcomes in acute pancreatitis (AP) among adults. Obesity is increasingly prevalent in children and hence, we sought to evaluate the impact of morbid obesity on the clinical outcomes of AP using a large paediatric population‐based cohort.

Methods

We analysed the US Kids' Inpatient Database between years 2003 and 2016 to include all patients (age ≤ 21 years) with a primary diagnosis of AP using specific ICD‐9‐CM and ICD‐10‐CM codes. We compared clinical outcomes between children without obesity (controls) and those with morbid obesity (cases). The primary outcome was severe AP (2012 revised Atlanta classification) and secondary outcomes included healthcare resource utilization (length of stay and hospital costs).

Results

Among 36 698 paediatric AP hospitalizations, 1275 (3.5%) were found to have morbid obesity. From 2003 to 2016, the proportion of children with morbid obesity among AP patients increased from 1.3% to 5.5% (P < .001). More than half (54%) of the children with morbid obesity were presented with cholelithiasis as contributive aetiology. The prevalence of severe AP was significantly higher in morbid obesity (7.3% vs 3.8%, P < .001). Multivariate analysis revealed that morbid obesity was increasingly associated with severe AP (OR 1.79, 95% CI 1.4, 2.26), prolonged hospitalization (by 0.41 days, P = .03), and higher hospital costs (by $1596, P < .001).

Conclusion

Unlike adult population, there is a lack of other confounding comorbidities in children and this national‐level analysis shows that morbid obesity independently prognosticates adverse clinical outcomes in paediatric AP.
Head‐to‐head comparison of cerebral blood flow single‐photon emission computed tomography and 18F‐fluoro‐2‐deoxyglucose positron emission tomography in the diagnosis of Alzheimer disease
Authors: Nadebaum David P. , Krishnadas Natasha , Poon Aurora M. T. , Kalff Victor , Lichtenstein Meir , Villemagne Victor L. , Jones Gareth , Rowe Christopher C.
Published: May 2020

Background

Clinical diagnosis of Alzheimer disease (AD) is only 70% accurate. Reduced cerebral blood flow (CBF) and metabolism in parieto‐temporal and posterior cingulate cortex may assist diagnosis. While widely accepted that 18F‐fluoro‐2‐deoxyglucose positron emission tomography (18F‐FDG PET) has superior accuracy to CBF‐SPECT for AD, there are very limited head‐to‐head data from clinically relevant populations and these studies relied on clinical diagnosis as the reference standard.

Aims

To compare directly the accuracy of CBF‐SPECT and 18F‐FDG PET in patients referred for diagnostic studies in detecting β‐amyloid PET confirmed AD.

Methods

A total of 126 patients, 56% with mild cognitive impairment and 44% with dementia, completed both CBF‐SPECT and 18F‐FDG PET as part of their diagnostic assessment, and subsequently underwent β‐amyloid PET for research purposes. Transaxial slices and Neurostat 3D‐SSP analyses of 18F‐FDG PET and CBF‐SPECT scans were independently reviewed by five nuclear medicine clinicians blinded to all other data. Operators selected the most likely diagnosis and their diagnostic confidence. Accuracy analysis used final diagnosis incorporating β‐amyloid PET as the reference standard.

Results

Clinicians reported high diagnostic confidence in 83% of 18F‐FDG PET compared to 67% for CBF‐SPECT (P = 0.001). All reviewers showed individually higher accuracy using 18F‐FDG PET. Based on majority read, the combined area under the receiver operating characteristic curve in diagnosing AD was 0.71 for 18F‐FDG PET and 0.61 for CBF‐SPECT (P = 0.02). The sensitivity of 18F‐FDG PET and CBF‐SPECT was 76% versus 43% (P < 0.001), while specificity was 74% versus 83% (P = 0.45).

Conclusions

18F‐FDG PET is superior to CBF‐SPECT in detecting AD among patients referred for the assessment of cognitive impairment.
Retrospective single‐centre analysis of diagnostic approach to adult‐onset haemophagocytic lymphohistiocytosis
Authors: Lee Wei‐I. , Talaulikar Dipti , Cook Matthew C.
Published: May 2020

Background

Haemophagocytic lymphohistiocytosis (HLH) is a rare disorder with a poor prognosis characterised by substantial immune activation leading to end‐organ failure. In childhood, genetic defects that impair cytotoxic function of natural killer cells and T cells. (HLH) are often identified. In adults, clinical manifestations are similar to those observed in children but the aetiology is often unclear.

Aims

To evaluate whether poor prognosis for adult HLH is in part due to lack of awareness of the disorder, which results in incomplete investigation and failure to implement timely treatment.

Methods

We performed a retrospective case series of adult‐onset HLH in a tertiary hospital in Australia. We evaluated clinical characteristics, treatment and outcome, and related these to application of standard diagnostic criteria for HLH.

Results

In our centre, incomplete assessment of HLH criteria was common. Serum ferritin was the criterion most commonly assessed. Hyperferritinaemia ≥10 000 μg/L was highly sensitive in detecting patients with adult‐onset HLH; however, the majority of patients who had hyperferritinaemia ≥10 000 μg/L did not have adult‐onset HLH.

Conclusion

The present study highlights the importance of comprehensive application of diagnostic criteria to improve accuracy and timelines of the diagnosis of adult onset HLH.
Evaluation of calling criteria for the rapid response system utilising single versus multiple physiological parameter disturbances
Authors: Shoaib Muhammad , Chalmers Leanne , Richards Tobias , Carison John , Leman Peter
Published: May 2020

Background

The Adult Deterioration Detection System for Medical Emergency Team (MET) activation is widely used and includes single parameter (SP‐MET) and multiple parameter (MP‐MET) disturbances. Whether the patient characteristics, interventions and outcomes differ for SP‐MET compared with MP‐MET is uncertain.

Aims

To describe MET interventions and outcomes of SP versus MP MET in the Acute Medical Unit (AMU) of a tertiary care hospital.

Methods

Retrospective audit over 6 months comparing SP‐MET and MP‐MET groups.

Results

SP‐MET constituted 64.1% (168) of 262 AMU MET calls, most commonly for hypotension (35.5%) and tachycardia (14.1%). There were no significant differences in demographic and disease characteristics between the two groups. Common interventions included fluid/electrolyte replacement in 139 (52%), oxygen therapy in 46 (17%) and non‐invasive ventilation in 33 (13%) patients. After MET intervention, 82.4% patients stayed on the ward, 8.4% died/were palliated, 6.5% were transferred to the Intensive Care Unit (ICU) and 2.7% patients required urgent transfer to the theatre for intervention. SP‐MET patients were more likely to remain on the ward (88.7% vs 71.3%; P = 0.001), receive ward‐based interventions (85.1% vs 61.7%; P < 0.001) and less likely to experience death/palliation (4.2% vs 16%, P = 0.001) compared with the MP‐MET group. MP‐MET were independently associated with negative outcomes (OR 3.10; 95% CI 1.60–6.00).

Conclusion

SP‐MET identify a cohort of patients at lower risk of requiring escalation of care and ICU admission. Given the resource intensity of MET activation, further research is warranted to determine whether alternative response strategies are appropriate for selected SP disturbances.
The effects of 11‐ketotestosterone implants on transcript levels of gonadotropin receptors, and foxl2 and dmrt1 genes in the Previtellogenic ovary of cultured beluga (Huso huso)
Authors: Rahdari Abdolali , Khoshkholgh Majidreza , Yarmohammadi Mahtab , Ortiz‐Zarragoitia Maren , Lokman Pieter Mark , Akhavan Sobhan R. , de Cerio Oihane Diaz , Cancio Ibon , Falahatkar Bahram
Published: May 2020

The in vivo effect of 11‐ketotestosterone (11KT) on transcript levels of the gonadotropin receptors (fshr and lhr) and sex differentiation‐related genes (dmrt1 and foxl2) was examined in the ovaries of immature female beluga. For this purpose, six fish were treated with implants containing 2.5 mg 11KT and a placebo group of six females of the same age and gametogenic stage were given a blank implant. The implants were intraperitoneally inserted into 4‐year‐old females at the previtellogenic stage (mean body weight 5580 ± 165 g) and maintained under culture conditions for 8 weeks. Ovary samples for gene expression analysis of lhr, fshr, dmrt1 and foxl2 were collected by biopsy at 3 and 8 weeks post implantation. Diameters of oocytes increased in response to 11KT treatment, both at 3 and at 8 weeks post implantation, but no obvious changes were evident in cytology. Three weeks of 11KT treatment did not affect target gene expression, but a tendency for a time‐dependent decrease of lhr and dmrt1 mRNA levels was observed in both treatment and placebo groups. By 8 weeks of treatment, however, 11KT implants provoked the upregulation of fshr and foxl2 transcript levels. Furthermore, lhr and dmrt1 transcript abundances recovered by 8 weeks of exposure in both blank‐ and 11KT‐implanted beluga. These results suggest that 11KT, either directly or indirectly, may affect gametogenesis and regulate some key components of the reproductive axis in female beluga.